bluuebunny/crossref_metadata_2025 huggingface dataset:
Substitutions at the C-8 position of quinazolin-4-ones improve the potency of nicotinamide site binding tankyrase inhibitors
Authors: Bosetti Chiara , Kampasis Dionisis , Galera-Prat Albert , Brinch Shoshy A. , Karelou Maria , Dhakar Saurabh S. , Alaviuhkola Juho , Waaler Jo , Lehtiö Lari , Kostakis Ioannis
Published: June 2024

Human diphtheria toxin-like ADP-ribosyltransferases, PARPs and tankyrases, transfer ADP-ribosyl groups to other macromolecules, thereby controlling various signaling events in cells. They are considered promising drug targets, especially in oncology, and some small molecule inhibitors have already been developed. These inhibitors typically interact with the nicotinamide binding site and extend along the NAD+binding groove of the catalytic domain. Quinazolin-4-ones have been explored as promising scaffolds for such inhibitors and we have identified a new position within the catalytic domain that has not been extensively studied yet. In this study, we investigate larger substituents at the C-8 position and, using X-ray crystallography, we demonstrate that nitro- and diol-substituents engage in new interactions with TNKS2, improving both affinity and selectivity. Both nitro- and diol-substituents exhibit intriguing inhibition of TNKS2, with compound49displaying an IC50of 65 nM, while compound40’s IC50value is 14 nM. Both analogues show efficacy in cell assays and attenuate the tankyrase-controlled Wnt/β-catenin signaling with sub-micromolar IC50. When tested against a wider panel of enzymes, compound40displayed high selectivity towards tankyrases, whereas49also inhibited other PARPs. The results offer new insights for inhibitor development targeting tankyrases and PARPs by focusing on the subsite between a mobile active site loop and the canonical nicotinamide binding site.
Time is Brain: Detection of Nonconvulsive Seizures and Status Epilepticus During Acute Stroke Evaluation Using Point-of-Care Electroencephalography
Authors: Gururangan Kapil , Kozak Richard , Dorriz Parshaw J.
Published: June 2024

Objectives

Seizures are both a common mimic and a potential complication of acute stroke. Although EEG can be helpful to evaluate this differential diagnosis, conventional EEG infrastructure is resource- intensive and unable to provide timely monitoring to match the emergent context of a stroke code. We aimed to evaluate the real-world use and utility of a point-of-care EEG device as an adjunct to acute stroke evaluation.

Materials and Methods

We performed a retrospective observational cohort study at a tertiary care community teaching hospital by identifying patients who underwent point-of-care EEG monitoring using Rapid Response EEG system (Ceribell Inc., Sunnyvale, CA) during stroke code evaluation of acute neurological deficits during the study period from January 1, 2020 to December 31, 2020. We assessed the frequency of seizures and highly epileptiform patterns among patients with either confirmed strokes or stroke mimics.

Results

Point-of-care EEG monitoring was used in the wake of a stroke code in 70 patients. Of these, neuroimaging and clinical information resulted in a diagnosis of stroke in 38 patients (28 ischemic, 6 hemorrhagic, 4 transient ischemic attack; median NIHSS score of 6.5 [IQR 2.0-12.0]) and absence of any stroke in 32 patients. Point-of-care EEG detected seizures and highly epileptiform patterns in 6 (15.8%) stroke patients and 11 (34.4%) stroke-mimic patients, including 2 patients with persistent expressive aphasia due to repeated focal seizures.

Conclusions

Point-of-care EEG has utility for detecting nonconvulsive seizures in patients undergoing acute stroke evaluations.
tame: An R package for identifying clusters of medication use based on dose, timing and type of medication
Authors: Laksafoss Anna , Wohlfahrt Jan , Hviid Anders
Published: June 2024

Simplified exposure classifications, such as ever exposed versus never exposed, are commonly used in pharmacoepidemiology. However, this simplification may obscure complex use patterns relevant to researchers. We introduce tame, an R package that offers a novel method for classifying medication use patterns, capturing complexities such as timing, dose, and concurrent medication use in real-world data. The core innovation of tame is its bespoke distance measure, which identifies complex clusters in medication use and is highly adaptable, allowing customization based on the Anatomical Therapeutic Chemical (ATC) Classification System, medication timing, and dose. By prioritizing a robust distance measure, tame ensures accurate and meaningful clustering, enabling researchers to uncover intricate patterns within their data. The package also includes tools for visualizing and applying these clusters to new datasets. In a national Danish cohort study, tame identified nuanced antidepressant use patterns before and during pregnancy, demonstrating its capability to detect complex trends. tame is available on the Comprehensive R Archive Network at [https://CRAN.R-project.org/package=tame] under an MIT license, with a development version on GitHub at [https://github.com/Laksafoss/tame]. tame enhances medication use classification by detecting complex interactions and offering insights into real-world medication usage, thus improving stratification in epidemiological studies.
Milliseconds matter: Biomechanical inverse dynamics analysis is highly sensitive to imperfect data synchronization
Authors: Lemaire Koen K. , Kuo Arthur D.
Published: June 2024

Inverse dynamics analysis is the primary means of quantifying joint moments and powers from biomechanical data. The data are often combined from force plates, motion capture cameras, and perhaps body-worn inertial sensors, and must be temporally synchronized to avoid potentially large inverse dynamics errors. The principles behind the errors, and the sensitivities for movements such as human walking, have yet to be demonstrated. Here we quantify how inverse dynamics computations of joint moments, powers, and work are highly sensitive to temporal mis-synchronization. We do this with (1) a theoretical examination of inverse dynamics, supported by (2) a simulated multi-body jumping movement, and (3) experimental human walking data. The theoretical analysis shows that root-mean-square errors in joint powers increase linearly with temporal mis-synchronization, and increase more for faster movements. With the other analyses we quantify the specific amount. For example, for human walking at 1.25 m/s, an artificially induced 5 ms lag of force relative to motion resulted in a 29% root-mean-square error of the ankle joint moment. The corresponding error in ankle joint power was 58%, and five times as much for walking at 2.2 m/s. The residual force, a measure of internal inconsistency in the data, increased by almost 1% body weight for each millisecond of mis-synchronization for walking. These sensitivities are relevant because standard experimental equipment usually synchronizes only the recording of data, but not processing latencies internal to equipment, which can and do cause mis-synchronization on the order of ten milliseconds. Biomechanical data should be synchronized to within a few milliseconds, and with respect to physical stimulus, to yield accurate inverse dynamics analysis.
The role of two major nucleoid associated proteins in Streptomyces, HupA and HupS, in stress survival and gene expression regulation
Authors: Strzałka Agnieszka , Mikołajczyk Jakub , Kowalska Klaudia , Skurczyński Michał , Holmes Neil , Jakimowicz Dagmara
Published: June 2024

Streptomycesare sporulating soil bacteria with enormous potential for secondary metabolites biosynthesis. Regulatory networks governingStreptomyces coelicolordifferentiation and secondary metabolites production are complex and composed of numerous regulatory proteins ranging from specific transcriptional regulators to sigma factors. Nucleoid associated proteins (NAPs) are also believed to contribute to regulation of gene expression. Upon DNA binding these proteins impact DNA accessibility. Among NAPs HU proteins are the most widespread and abundant. Unlike other bacteria, theStreptomycesgenome encodes two HU homologs: HupA and HupS, differing in structure and expression profile. In this study, we explore whether HupA and HupS affectS. coelicolorgrowth under optimal and stressful conditions and how they control global gene expression. By testing both single and double mutants we address the question of both HU homologs complementarity. The lack of bothhupgenes led to growth and sporulation inhibition, as well as increased spore fragility. Our data indicate a synergy between the functions of HupA and HupS duringS. coelicolorgrowth. We also demonstrate, that both HU homologs can be considered global transcription regulators influencing expression of numerous genes encoding proteins linked to chromosome topology, secondary metabolites production and transcription. We identify the independent HupA and HupS regulons as well as genes under the control of both HupA and HupS proteins. Our data indicate some extent of redundancy as well as independent function of both homologs.

Importance

Streptomycesbelong to the bacterial family widely used in the production of antibiotics as well as research for new bioactive substances with antimicrobial properties. Gene expression inStreptomyces, and consequently the production of secondary metabolites, is controlled by a vast and complex network of transcriptional regulators. Our data indicate that two proteins, HupA and HupS, involved in the maintenance of chromosome structure, also participate in this regulatory network. Their presence appears to important forS. coelicolor’s adaptation for survival in unfavorable conditions such as high temperature. The lack of one or both HU proteins affects the expression of many genes, indicating that they act as global transcriptional regulators.
Foci, waves, excitability : self-organization of phase waves in a model of asymmetrically coupled embryonic oscillators
Authors: Roy Kaushik , François Paul
Published: June 2024

The ‘segmentation clock’ is an emergent embryonic oscillator that controls the periodic formation of vertebrae precursors (or somites). It relies on the self-organization at the Pre Somitic Mesoderm (PSM) level of multiple coupled cellular oscillators. Dissociation-reaggregation experiments have further revealed that ensembles made of such cellular oscillators self-organize into an oscillatory bidimensional system, showing concentric waves around multiple foci. Here, we systematically study the dynamics of a two dimensional lattice of phase oscillators locally coupled to their nearest neighbors through a biharmonic coupling function, of the form sinθ+ Λ sin2θ. This coupling was inferred from the Phase Response Curve (PRC) of entrainment experiments on cell cultures, leading to the formulation of a minimal Elliptic Radial Isochron Cycle (ERIC) phase model. We show that such ERIC-based coupling parsimoniously explains the emergence of self-organized concentric phase wave patterns around multiple foci, for a range of weak couplings and wide distributions of initial random phases, closely mimicking experimental conditions. We further study extended modalities of this problem to derive an atlas of possible behaviours. In particular, we predict the dominant observation of spirals over target wave patterns for initial phase distributions wider than approximatelyπ. Since PSM cells further display properties of an excitable system, we also introduce excitability into our simple model, and show that it also supports the observation of concentric phase waves for the conditions of the experiment. Our work suggests important modifications that can be made to the simple phase model with Kuramoto coupling, that can provide further layers of complexity and can aid in the explanation of the spatial aspects of self-organization in the segmentation clock.
A conserved interaction between the effector Sca4 and host endocytic machinery suggests additional roles for Sca4 during rickettsial infection
Authors: Vondrak Cassandra J , Sit Brandon , Suwanbongkot Chanakan , Macaluso Kevin R. , Lamason Rebecca L.
Published: June 2024

Intracellular bacterial pathogens deploy secreted effector proteins that manipulate diverse host machinery and pathways to promote infection. Although many effectors carry out a single specific function or interaction, there are a growing number of secreted pathogen effectors capable of interacting with multiple host factors. However, few effectors secreted by obligate intracellularRickettsiaspecies have been linked to multiple host targets. Here, we investigated the conserved rickettsial secreted effector Sca4, which was previously shown to interact with host vinculin to promote cell-to-cell spread in the modelRickettsiaspeciesR. parkeri. We discovered that Sca4 also binds the host cell endocytic factor clathrin heavy chain (CHC,CLTC) via a conserved segment in the Sca4 N-terminus. Ablation ofCLTCexpression or chemical inhibition of endocytosis reducedR. parkericell-to-cell spread, indicating that clathrin promotes efficient spread between mammalian cells. This activity was independent of Sca4 and appeared restricted to the recipient host cell, suggesting that the Sca4-clathrin interaction also regulates another aspect of the infectious lifecycle. Indeed,R. parkerilacking Sca4 or expressing a Sca4 truncation unable to bind clathrin had markedly reduced burdens in tick cells, hinting at a cell-type specific function for the Sca4-clathrin interaction. Sca4 homologs from diverseRickettsiaspecies also bound clathrin, suggesting that the function of this novel effector-host interaction may be broadly important for rickettsial infection. We conclude that Sca4 has multiple targets during infection and that rickettsiae may manipulate host endocytic machinery to facilitate several stages of their life cycles.
Skeletal effects of sleeve gastrectomy, by sex and menopausal status and in comparison to Roux-en-Y gastric bypass surgery
Authors: Wu Karin C , Wu Po-Hung , Kazakia Galateia , Patel Sheena , Black Dennis M , Lang Thomas F , Kim Tiffany Y , King Nicole J , Hoffman Thomas J. , Chang Hanling , Linfield Gaia , Palilla Sarah , Rogers Stanley J , Carter Jonathan T , Posselt Andrew M , Schafer Anne L
Published: June 2024

Context

Roux-en-Y gastric bypass (RYGB) has deleterious effects on bone mass, microarchitecture, and strength. Data are lacking on the skeletal effects of sleeve gastrectomy (SG), now the most commonly performed bariatric surgical procedure.

Objective

We examined changes in bone turnover, areal and volumetric bone mineral density (aBMD, vBMD), and appendicular bone microarchitecture and estimated strength after SG. We compared the results to those previously reported after RYGB, hypothesizing lesser effects after SG than RYGB.

Design, Setting, Participants

Prospective observational cohort study of 54 adults with obesity undergoing SG at an academic center.

Main Outcome Measure(s)

Skeletal characterization with biochemical markers of bone turnover, dual-energy X-ray absorptiometry (DXA), quantitative computed tomography (QCT), and high-resolution peripheral QCT (HR-pQCT) was performed preoperatively and 6- and 12-months postoperatively.

Results

Over 12 months, mean percentage weight loss was 28.8%. Bone turnover marker levels increased, and total hip aBMD decreased −8.0% (95% CI −9.1%, −6.7%, p<0.01). Spinal aBMD and vBMD declines were larger in postmenopausal women than men. Tibial and radial trabecular and cortical microstructure worsened, as did tibial estimated strength, particularly in postmenopausal women. When compared to data from a RYGB cohort with identical design and measurements, some SG biochemical, vBMD, and radial microstructural parameters were smaller, while other changes were not.

Conclusions

Bone mass, microstructure, and strength decrease after SG. Some skeletal parameters change less after SG than after RYGB, while for others, we find no evidence for smaller effects after SG. Postmenopausal women may be at highest risk of skeletal consequences after SG.
Individual Participant Data Network Meta-analysis of psychosocial interventions for survivors of intimate partner violence: Study protocol
Authors: Palantza Christina , Morgan Karen , Welton Nicky J. , Micklitz Hannah M. , Sander Lasse B. , Feder Gene
Published: June 2024

Many systematic reviews and meta-analyses have been conducted in the field of Intimate Partner Violence (IPV) and the evidence shows small to moderate effect sizes in improving mental health. However, there is considerable heterogeneity due to great variation in participants, interventions and contexts. It is therefore important to establish which participant and intervention characteristics affect the different psychosocial outcomes in different contexts. Individual Participant Network Meta-analysis (IPDNMA) is a gold-standard method to estimate the effects with the highest precision possible and estimate moderating effects, compare the effectiveness of the different interventions and thus answer the question of which intervention is best-suited for whom. We will conduct an IPDNMA of randomised controlled trials (RCTs) of psychosocial interventions for IPV survivors aimed at improving mental health, well-being, risk-lowering and intervention acceptability outcomes compared to any type of control (PROSPERO registration number: CRD42023488502). We aim to establish a collaboration with the authors of the eligible RCT, to obtain and to harmonise the Individual Participant Data of the trials, and conduct an one-stage IPDNMA will be conducted under a Bayesian framework using the multinma package in R, after testing which characteristics of the participants and interventions are effect modifiers. There are however inherent limitations of IPDMAs, such as depending on data availability and missing nuancing through the harmonisation of variables. We aim to address these possibly by creating pseudo-IPD and sensitivity analyses. This approach is novel in the field and it can inform more efficient clinical and policy-related decision making.
KCNG4 genetic variant linked to migraine prevents expression of KCNB1
Authors: Lacroix Gabriel , Bhat Shreyas , Shafia Zerghona , Blunck Rikard
Published: June 2024

Abstract

Migraines are a common type of headaches affecting around 15% of the population. The signalling pathways leading to migraines have not been fully understood, but neuronal voltage-gated ion channels have been linked to this pathology, among them KCNG4. KCNG4 (Kv6.4) is a silent member of the superfamily of voltage-gated potassium (Kv) channels, which expresses in heterotetramers with members of the KCNB (Kv2) family. The genetic variant Kv6.4-L360P has previously been linked to migraine, but their mode of action remains unknown. Here, we characterized the molecular characteristics of Kv6.4-L360P when co-expressed with Kv2.1. We found that Kv6.4-L360P almost completely abolishes Kv2 currents, and we propose that this mechanism in the trigeminal system, linked to the initiation of migraine, leads to the pathology.
Fabry-Pérot and Friedrich-Wintgen bound states in the continuum in a photonic triple-stub cavity
Authors: Rezzouk Yamina , Khattou Soufyane , El Ghafiani Mohamed , Amrani Madiha , El Boudouti El Houssaine , Talbi Abdelkrim , Djafari-Rouhani Bahram
Published: June 2024

Bound states in the continuum (BICs) are zero-width (infinite lifetime) trapped eigenmodes that remain confined in the system even though they coexist with a continuum of extended states. The resulting high-frequency resonances may have significant applications in photonic integrated circuits, filtering, sensing, and laser. In this paper, we demonstrate that a simple design based on a photonic triple-stub cavity can display both Fabry-Pérot (FP) and Friedrich-Wintgen (FW) BICs, and their occurrence is very dependent on the way the cavity is attached to the outside medium by one or two ports. We first consider a symmetric cavity where a stub of length d3 is surrounded by two stubs of length d2, and all stubs are separated by segments of length d1. When the cavity is inserted between two ports, we demonstrate theoretically and validate experimentally the existence of symmetric BICs (S-BIC) and antisymmetric BICs (AS-BIC) of FP type under commensurability conditions between the lengths d1, d2, and d3. The S-BICs and AS-BICs may cross each other, giving rise to a doubly degenerate BIC. By breaking the symmetry of the cavity, AS-BICs and S-BICs can couple together and realize a FW-type BIC where one resonance remains with zero width while the other broadens into a bright mode. By considering two additional configurations where the triple-stub cavity is attached with one or two ports from only one side, additional BICs can be induced inside the structure. By slightly detuning from the BIC condition, the latter transforms into either an electromagnetic-induced transparency/reflection or Fano resonance. Finally, such a triple-stub cavity can be designed to realize near-perfect absorption for some frequencies. All the analytical results, obtained from the Green's function method, have been confirmed experimentally in the radiofrequency domain using coaxial cables.

Published by the American Physical Society
2024
Chiral analysis of the nucleon mass and sigma commutator
Authors: Owa S. , Leinweber D. B. , Thomas A. W. , Wang X. G.
Published: June 2024

Schemes for describing the light quark mass dependence of the nucleon mass calculated in lattice QCD are compared. The three schemes in consideration include a fully relativistic and Lorentz covariant scheme, one that is fully relativistic but not Lorentz covariant, and a semirelativistic scheme utilizing the heavy baryon approximation. Calculations of observables involving pseudoscalar meson loop diagrams generate nonanalytic terms proportional to square roots and logarithms of the quark mass. The three schemes all yield the correct model-independent leading and next-to-leading nonanalytic terms of the chiral expansion of the baryon mass. Results for the masses of the other members of the octet are also presented. Here, low-energy coefficients of the analytic terms of the expansion for the nucleon and hyperons are constrained by lattice QCD results and are demonstrated to be independent of the renormalization scheme used. The differences in the leading coefficient of the chiral expansions are found to be consistent with strange quark counting. Using the schemes examined herein, we report results for the pion-nucleon sigma commutator based upon recent lattice results from the CLS Collaboration. We find σπN=51.7±3.2±1.4  MeV, where the uncertainties are statistical and systematic, respectively.

Published by the American Physical Society
2024
Toward a covariant framework for post-Newtonian expansions for radiative sources
Authors: Hartong Jelle , Musaeus Jørgen
Published: June 2024

We consider the classic problem of a compact fluid source that behaves nonrelativistically and that radiates gravitational waves. The problem consists of determining the metric close to the source as well as far away from it. The nonrelativistic nature of the source leads to a separation of scales resulting in an overlap region where both the 1/c and (multipolar) G expansions are valid. Standard approaches to this problem (the Blanchet-Damour and the DIRE approach) use the harmonic gauge. We define a “post-Newtonian” class of gauges that admit a Newtonian regime in inertial coordinates. In this paper we set up a formalism to solve for the metric for any post-Newtonian gauge choice. Our methods are based on previous work on the covariant theory of nonrelativistic gravity (a 1/c expansion of general relativity that uses post-Newton-Cartan variables). At the order of interest in the 1/c and G expansions we split the variables into two sets: transverse and longitudinal. We show that for the transverse variables the problem can be reduced to inverting Laplacian and d’Alembertian operators on their respective domains subject to appropriate boundary conditions. The latter are regularity in the interior and asymptotic flatness with a Sommerfeld no-incoming radiation condition imposed at past null infinity. The longitudinal variables follow from the gauge choice. The full solution is then obtained by the method of matched asymptotic expansion. We show that our methods reproduce existing results in harmonic gauge to 2.5PN order.

Published by the American Physical Society
2024
Crystal structure determination and analyses of Hirshfeld surface, crystal voids, intermolecular interaction energies and energy frameworks of 1-benzyl-4-(methylsulfanyl)-3a,7a-dihydro-1H-pyrazolo[3,4-d]pyrimidine
Authors: Mustaphi Nour El Hoda , Chlouchi Amina , El Hafi Mohamed , Mague Joel T. , Hökelek Tuncer , El Monfalouti Hanae , Haoudi Amal , Mazzah Ahmed
Published: June 2024

The pyrazolopyrimidine moiety in the title molecule, C13H12N4S, is planar with the methylsulfanyl substituent lying essentially in the same plane. The benzyl group is rotated well out of this plane by 73.64 (6)°, giving the molecule an approximate L shape. In the crystal, C—H...π(ring) interactions and C—H...S hydrogen bonds form tubes extending along the a axis. Furthermore, there are π–π interactions between parallel phenyl rings with centroid-to-centroid distances of 3.8418 (12) Å. A Hirshfeld surface analysis of the crystal structure indicates that the most important contributions to the crystal packing are from H...H (47.0%), H...N/N...H (17.6%) and H...C/C...H (17.0%) interactions. The volume of the crystal voids and the percentage of free space were calculated to be 76.45 Å3 and 6.39%, showing that there is no large cavity in the crystal packing. Evaluation of the electrostatic, dispersion and total energy frameworks indicate that the cohesion of the crystal structure is dominated by the dispersion energy contributions.
A review of physical properties of hot-dip galvanized coating layer by layer and their respective electrochemical corrosion behavior
Authors: Li Zhiwei , Li Dingding , Zhou Yulong , Peng Haoping , Xie Aijun , Wang Jianhua
Published: June 2024

Purpose

This paper aims to contribute to the performance improvement and the broader application of hot-dip galvanized coating.

Design/methodology/approach

First, the ability to provide barrier protection, galvanic protection, and corrosion product protection provided by hot-dip galvanized coating is introduced. Then, according to the varying Fe content, the growth process of each sublayer within the hot-dip galvanized coating, as well as their respective microstructures and physical properties, is presented. Finally, the electrochemical corrosion behaviors of the different sublayers are analyzed.

Findings

The hot-dip galvanized coating is composed of η-Zn sublayer, ζ-FeZn13 sublayer, δ-FeZn10 sublayer, and Γ-Fe3Zn10 sublayer. Among these sublayers, with the increase in Fe content, the corrosion potential moves in a noble direction.

Research limitations/implications

There is a lack of research on the corrosion behavior of each sublayer of hot-dip galvanized coating in different electrolytes.

Practical implications

It provides theoretical guidance for the microstructure control and performance improvement of hot-dip galvanized coatings.

Originality/value

The formation mechanism, coating properties, and corrosion behavior of different sublayers in hot-dip galvanized coating are expounded, which offers novel insights and directions for future research.
Effect of wall length on an interacting supersonic rectangular jet
Authors: Manikanta T.V.S. , Sridhar B.T.N.
Published: June 2024

Purpose

This study aims to study the interaction effects between a rectangular supersonic jet with a flat wall computationally using wall length as a parameter. The purpose of this study is to investigate the effect of change in wall length on supersonic core length (SCL) reduction, jet deflection and jet decay behavior.

Design/methodology/approach

The design Mach number and aspect ratio at the rectangular exit were 1.8 and 2, respectively. To study the wall length effects on jet-wall interactions, wall length (Lw) was varied as 0.5Dh, 1Dh, 2Dh, 4Dh and 8Dh, where Dh was the hydraulic diameter of the nozzle exit. The flat wall with the matching width of the rectangular exit section of a supersonic nozzle was placed at the nozzle exit such that the supersonic jet grazed past the wall. The studies were carried out at over-expansion [nozzle pressure ratio (NPR) = 4], near optimum expansion (NPR = 6) and under-expansion (NPR = 8) levels.

Findings

Results indicated that significant reduction in wall-bounded SCL was noticed in the range of 0.5Dh 

≤  Lw

≤ 1Dh for both over-expansion and under-expansion conditions. At Lw

≥ 4Dh, SCL got enhanced at NPR = 4 and 6 but had a negligible effect at NPR = 8.

Practical implications

Thrust vector control, noise reduction and easy take-off for high-speed aircraft.

Originality/value

The effect of change in flat wall length on interaction characteristics of a rectangular supersonic jet was not studied before in terms of SCL reduction and jet decay behavior.
The impact of institutions, industry, and scale of operations on foreign subsidiaries’ political connections: evidence from Saudi Arabia and Egypt
Authors: Baokbah Ashjan , Shirodkar Vikrant
Published: June 2024

Purpose

Research on the political connections of multinational enterprises’ (MNEs’) subsidiaries in emerging host countries has been growing. The purpose of this paper is to integrate institutional and resource dependence theories to argue that MNEs-subsidiaries are likely to develop fewer formal (i.e. board-level) political connections when operating in welfare-state monarchies as compared to in host countries with developmental-state democratic systems. Furthermore, this paper argues that MNE-subsidiaries develop formal political connections to a greater extent in industries where religion influences the development of products and services considerably. Finally, the extent of developing formal political connections varies by the scale of the MNEs’ investment (or subsidiary density) in the host market.

Design/methodology/approach

The paper tests its hypotheses on a sample of foreign-owned subsidiaries operating in Saudi Arabia and Egypt. The data was collected by combining information from Bureau Van Dijk’s Orbis database with company websites and other secondary sources. The final sample consisted of 156 observations – 70 MNEs-subsidiaries operating in Saudi Arabia, and 86 in Egypt.

Findings

The findings confirm that foreign subsidiaries are likely to develop fewer formal political connections in a welfare-state monarchy as compared to in a developmental-state democratic system. Furthermore, formal political connections are more significant in industries that are impacted by the influence of religion – such as the financial industry in Arab countries. Finally, the extent of using political connections varies by the scale of the MNEs’ investment in the host market – that is, with a greater scale of investment (or higher subsidiary density), formal political connections are greater.

Originality/value

The paper contributes theoretically by explaining that a combination of institutional heterogeneity and its associated resource dependence conditions between MNEs and host governments influence MNE-subsidiaries' political connections. The paper tests its hypotheses in an emerging Arab context, which is characterized by both autocratic and semi-democratic political settings, and which makes the integration of institutional and resource dependence theories useful in explaining how MNE-subsidiaries navigate local complexities in this region.
A generative design-based optimization model for multi-objective construction site layout planning
Authors: Wefki Hossam , Salah Mona , Elbeltagi Emad , Elsheikh Asser , Khallaf Rana
Published: June 2024

Purpose

Given the growing interest in modern construction techniques and the emergence of innovative technologies, construction site layout planning research has progressively been investigating approaches to adopt innovative concepts and incorporate renewed approaches to improve widespread efficiency. This research develops a decision-making tool that optimizes construction site layout plans. The developed model targets two main objectives: minimizing material transportation costs and maximizing safety by optimally placing facilities on construction sites.

Design/methodology/approach

A novel approach is devised based on the integration of Building Information Modeling and Generative Design (BIM-GD). This engine is used to optimize the multi-objective site layout problems to identify layout alternatives in the early project stages. Parametric modeling uses Dynamo to construct the model and explore constraints initially. Finally, the GD environment is utilized to create different design alternatives, and then the decision-making procedure selects the most appropriate design alternative. Additionally, a case study is applied to validate the effectiveness of the developed model.

Findings

The results indicate the effectiveness of the proposed GD tool and its potential for more complex applications. The GD engine examined optimal layout plans, balancing different objectives and adhering to appointed geometric constraints. A case study was conducted to assess the model's effectiveness and showcase its suitability. Construction Site Layout Planning (CSLP) is an essential step in design that can influence considerable aspects, such as material transportation expenses and different safety standards on the site. Employing visual programming for parametric modeling within Dynamo-Revit creates an expedient and user-friendly platform for planning engineers who may require more programming expertise to create and program algorithmic models visually. Utilizing GD in CSLP has proven to be a powerful tool with consequential prospects for improving applications and executing more models.

Practical implications

The findings from this framework are intended to help construction practitioners select the most appropriate site layout during early project stages while incorporating different safety criteria inside construction sites to alleviate actual safety risks.

Originality/value

A new approach is proposed that utilizes an integrated BIM-GD engine to optimize multi-objective site layout problems. This approach targets two main objectives: minimizing material transportation costs and maximizing safety by optimally placing facilities in construction sites.
On some operations on grey graphs with application
Authors: Atef Mohammed , Liu Sifeng
Published: June 2024

Purpose

The objective of this paper is to formulate the precise meanings of grey graphs and examine some of their properties.

Design/methodology/approach

This article introduces innovative concepts of grey sets based on the grey number. We establish the grey graphs and examine their essential properties as isomorphisms of these graphs. Additionally, we explore the notion of a grey-complete graph and demonstrate certain properties of self-complementary grey-complete graphs.

Findings

We showcase novel facets of grey system theory through the establishment of the structures of grey graphs, and the subsequent analysis of their distinctive traits.

Practical implications

This article provides us with a new theoretical direction for grey system theory according to grey numbers. Thus, we present test examples that explain the routes between cities and the electrical wires between homes. Furthermore, the concept of grey graphs can be applied in several areas of engineering, computer science, neural networks, artificial intelligence, and medical diagnosis.

Originality/value

The proposed concepts are considered novel mathematical directions in grey system theory for the first time. Some operations of grey graphs are also explored.
Understanding the factors behind racial and ethnic disparities in the adoption of alternative financial services: a decomposition analysis
Authors: Lee Jonghee , Kim Kyoung Tae , Lee Jae Min
Published: June 2024

Purpose

The purpose of this study was to examine racial/ethnic differences in AFS use and their contributing factors using a decomposition analysis.

Design/methodology/approach

The 2018 National Financial Capability Study dataset was used to analyze the four major types of AFS—title loans, payday loans, pawnshops, and rent-to-own (RTO) stores—as proxies for AFS use. The study conducted both logistic regression analysis and decomposition analysis to examine the contributing factors.

Findings

The results of the logistic regression analysis demonstrated significant disparities in the use of alternative financial services (AFS) among racial and ethnic groups. Specifically, it was found that Blacks were more likely to utilize title and payday loans, pawnshops, and rent-to-own (RTO) stores compared to Whites. In contrast, Hispanics and Asians/individuals of other ethnicities were less likely to use title loans, but Hispanics were more likely to opt for payday loans over Whites. Furthermore, objective financial literacy exhibited a negative association with the likelihood of using these four types of AFS, whereas subjective financial literacy consistently showed a positive association. When examining the decomposition analyses, it became evident that both objective and subjective financial literacy played significant roles in explaining the racial and ethnic disparities in AFS usage. However, the patterns varied in three specific pairwise comparisons.

Originality/value

This study revealed the relative contributions of each factor to the racial/ethnic disparities through decomposition analysis. Our Fairlie decomposition approach addressed non-linearities within the decomposition framework, particularly in estimating the probabilities of AFS utilization, given its binary outcomes. This extension builds upon the Oaxaca decomposition. The study offers valuable insights into the variations in AFS use among different racial and ethnic groups.
The heterogeneous effects of macroeconomic and financial factors on financial deepening in Africa: evidence from a method of moments quantile regression analysis
Authors: Sanga Bahati , Aziakpono Meshach
Published: June 2024

Purpose

This paper aims to investigate the heterogeneous effects of macroeconomic and financial factors across various distributions of financial deepening in 22 African countries over the past two decades (2000–2019).

Design/methodology/approach

The paper uses a recent method of moments quantile regression, which accounts for the often overlooked heterogeneity effects. The analysis focuses on the banking sector, which is predominant in Africa, using a broad range of macroeconomic and financial indicators.

Findings

The findings show that gross domestic product per capita positively and significantly impacts financing deepening with an increasing marginal benefit as depth increases. Trade openness positively and substantially affects only high financial deepening. Real interest rate, real exchange rate and inflations negatively and significantly affect financial deepening, especially at higher than lower levels. Financial stability positively and substantially influences financial deepening with an increasing marginal benefit as the depth increases. Bank lending interest rate, bank lending–deposit rate spread, bank concentration and return on equity negatively and substantially impact higher levels of financial deepening than lower levels.

Practical implications

These findings are crucial to policymakers and development partners, as promoting a favourable financial environment and stable macroeconomic policies based on the heterogeneity of financial depths can increase debt financing in Africa.

Originality/value

To the best of the authors’ knowledge, this paper is one of the first attempts to analyse the heterogeneous effects of macroeconomic and financial determinants on varying levels of financial depth in Africa.
Knowledge management is no more a gray area in the tourism industry in India – a study on transformation leadership and executive communication
Authors: Luthra Anchal , Arya Vikas , Dixit Shivani , Roy Hiran , Sasso Pasquale
Published: June 2024

Purpose

Considering the important role of knowledge management in the global growth of world economies, the importance of knowledge management in the tourism industry can hardly be overestimated. Knowledge management, empowering leadership and innovation can open new research prospects for online travel and tourism, thereby increasing organizational capacity. In this context, this study aims to investigate the relationship between knowledge management practices and transformational leadership, along with the mediating role in this relationship of leadership communication. Knowledge management practices are discussed through the lens of managers’/organizational perspectives working in the online travel and tourism industry.

Design/methodology/approach

Using a descriptive research method, the data were collected from a total of 174 managers/senior executives working in the online travel and tourism sectors. The proposed conceptual framework was evaluated using structural equation modeling through AMOS 21 and Process Macro (SPSS-Plugin).

Findings

The results revealed a significant increase in the adoption of knowledge management practices in the online travel and tourism sector under transformative leadership. The results also highlighted that effective communication is a vital contributor and significant complementary mediator in the relationship between transformative leadership and knowledge management practices.

Practical implications

The results of this study suggest that transformational leaders, who are equipped with the “high touch” nature of leadership and the “high tech” aspect of the contemporary workplace, are the best fit to manage online travel and tourism organizations. To have an adequate knowledge management system, knowledge managers should adopt a transformative leadership style and receive comprehensive training in developing leadership abilities such as effective communication competencies.

Originality/value

To the best of the authors’ knowledge, this study is the first to demonstrate that, in emerging online travel and tourism sectors, organizational knowledge can be managed through effective leadership communication.
A 5C model of responsible service leadership: learning from living systems to play the infinite game
Authors: Livne-Tarandach Reut , Ball Joan , Arora Poonam , Yemiscigil Ayse , Kandampully Jay
Published: June 2024

Purpose

This paper offers a new vision of responsible service leadership for service organizations nested in economic, societal and environmental contexts across time to foster collective flourishing.

Design/methodology/approach

Following the call for novel perspectives that recognize service as a game among (vs between) people in service ecosystems, we build on service leadership theory to integrate insights from infinite (vs finite) games and biomimicry practices to propose a holistic model for responsible service leadership.

Findings

We extend the 3C (competence, character and care) model of service leadership (Shek et al., 2021) adding context and chronos as essential pillars of responsible service leadership in nested ecosystems. We offer new interpretations and applications of the 3Cs through the lens of context and chronos.

Research limitations/implications

This paper furthers the emerging conversation about unique leadership approaches for service, linking existing service leadership theories with holistic views of service ecosystems and enabling a shift from decontextualized models of leadership to a more inclusive approach.

Practical implications

We propose that responsible service leadership can inspire new approaches to leadership development within organizations and in business education (e.g. competencies, settings) and a reconsideration of organizational structures (e.g. culture, selection and incentive design).

Social implications

The proposed 5C model revisits foundational assumptions of responsibility in service leadership, integrating actors across and within service ecosystems, society at large and the environment in the present and future.

Originality/value

This paper offers a conceptual framework – the 5Cs model of responsible service leadership – aimed at reimagining service leadership.
Once upon a game: boosting brand storytelling through gamification
Authors: Vega Elias , Camarero Carmen
Published: June 2024

Purpose

The purpose of this study is to explore the impact of gamifying brand storytelling on user immersion in the brand narrative, a concept referred to as “narrative transportation”. The aim is to comprehend how transportation influences users’ experience and their responses to the brand, with particular focus on brand attitude and WOM. The study also explores the role of interactivity in brand storytelling and its effects on transportation and user engagement.

Design/methodology/approach

Four experiments were conducted to sequentially test the proposed hypotheses. Each experiment involves ad hoc gamified brand stories for different product categories (wine, museum, glasses and frozen fruit).

Findings

Findings indicate that including gamification elements in brand stories heightens narrative transportation and enhances the information obtained by users as well as their entertainment. Users thus respond more positively to the brand in terms of attitude and WOM. The study also reveals that high levels of interactivity in the game may actually decrease narrative transportation in the story, although this is offset by the perception of greater entertainment.

Originality/value

This research contributes to current understanding of brand storytelling and its impact on branding. It highlights the importance of offering users a gamified experience that can provide them with information about the brand whilst also offering them entertainment. The results also hold implications for gamification literature by emphasizing the need to ensure a balance between game and story vis-à-vis enhancing the impact of gamified storytelling on brand response.