bluuebunny/crossref_metadata_2025 huggingface dataset:
Insights into theforagingGene’s Influence on Mating Investments of MaleDrosophila
Authors: Li Wengjing , Huang Yongwen , Kim Woo Jae
Published: July 2024

Theforaginggene is a key genetic factor that modulates social behavior in insects, primarily by governing the trade-off between individual foraging and group-related activities. It has been associated with various behaviors associated with food search and resource exploitation, thereby playing a crucial role in determining the efficiency of foraging and the overall success of the collective. In this study, we investigate the critical role of theforaginggene in mediating complex interval timing behaviors, particularly mating duration, in the fruit flyDrosophila melanogaster. By examining two distinct variant phenotypes, rover and sitter, we observe specific deficiencies in longer (LMD) and shorter mating duration (SMD) behaviors, respectively, suggesting the gene’s crucial influence on these interval timing mechanisms. Utilizing single-cell RNA sequencing and knockdown experiments, we identify the gene’s significant expression in key neurons involved in learning and memory. However, its impact on mating duration is not observed in these brain regions. Instead, our data reveal the gene’s crucial role in specific neurons expressing Pdfr, a critical regulator of circadian rhythms. Furthermore, the study uncovers sexually dimorphic expression patterns in the brain and highlights the necessity of the gene’s dosage in specific cell populations within the ellipsoid body for normal mating duration. These findings underscore theforaginggene’s pivotal role in mediating complex interval timing behaviors inDrosophila, providing valuable insights into the intricate interplay between genetics, environment, and behavior. This research contributes to a deeper understanding of the genetic and neural mechanisms underlying complex interval timing behaviors, with broader implications for unraveling the function offoraginggene.
Predicting future patterns of land cover from climate projections using machine learning
Authors: Stepinski Tomasz F.
Published: July 2024

Vegetation plays a crucial role in the Earth’s system, and its characteristics are strongly influenced by climate. Previous studies have investigated the climate-vegetation relationship, often attempting to predict vegetation types based on climate data. Many of them have utilized biome types as proxies for different vegetation forms. Biomes, although widely used, are not always optimal for this task. They are broadly defined, a priori linked to climate, and subject to change over time. This study proposes a novel approach by using the local composition of land cover (LC) categories as descriptors of vegetation types and examines the feasibility of modeling such compositions based on climate data. The investigation focuses on the Sahel region of Africa, which is tessellated into 5 × 5 km square tiles, serving as the basic units of analysis. The independent variable comprises a set of bioclimatic variables assigned to each tile, while the dependent variable consists of shares of each LC category within the tile. The modeling framework involves a set ofnregressions, one for each LC category. The K-nearest neighbors (KNN) algorithm is employed to ensure that interdependently predicted shares sum up to 100%. The model’s performance is validated using 2010 data, where both climate and LC information are available. The mean absolute value of residuals ranges from 1% to 11%, depending on the LC category. Subsequently, future predictions of LC patterns are made for 2040, 2070, and 2100 using climate projections under IPCC scenarios 370 and 585. A novel visualization technique called synthetic landscape is introduced to visually compare the temporal sequence of predicted LC maps from 2010 to 2100 with similar sequences of biome maps and Köppen-Geiger climate type maps. This comparison highlights overall similarities across all sequences but also reveals some significant differences.
Optimum Push-off During Uneven Walking for Just-in-Time Strategy; Delayed Push-off Exertion is Mechanically Costly
Authors: Hosseini-Yazdi Seyed Saleh
Published: July 2024

It is shown that step mechanical work roughly describes walking energetics, and optimal walking economy is achieved by pre-emptive step work. We suggest this is also true for uneven walking. Using a simple powered walking model, we estimated the preferred pre-emptive push-offs to cover the entire step energy. The maximum push-off is exerted when the subsequent heel-strike dissipation is zero, setting an upper bound for step-up amplitude achievable with pre-emptive push-off. For instance, at a walking speed of 1.4 m · s−1, the maximum step-up is 0.106 m. Conversely, for any step-up amplitude, there is a minimum walking speed. For a step-up height (Δh) of 0.06 m, the minimum walking speed is 1.06 m · s−1. The importance of pre-emptive push-off and optimal timing of push-off and collision is widely discussed. However, there are cases where this timing is undermined, such as during uneven walking, necessitating post-transition mechanical energy compensation. The ankle (via delayed push-off) or hip can provide mid-flight energy, but no mechanical determinant prefers one source over the other. Our modeling demonstrates that delayed push-off entails mechanical energy waste, likely converted to heat by stretching the stance leg. This stretch may also release energy stored during the heel-strike (e.g., in the Achilles tendon), exacerbating the required mechanical work performance in the subsequent step transition. Hence, we propose that during the double support phase, when the stance leg is switched, hip actuation becomes mechanically preferable. Physiological observations also support our proposition.
Grape extract and resveratrol mitigate sleep fragmentation, Aβ accumulation, and abnormal neuronal excitability in aDrosophilamodel of Alzheimer’s disease
Authors: Yu Ziqi , Xu Yangkun , Ping Yong
Published: July 2024

Consumption of red wine and grape extracts may offer a range of health benefits, largely attributable to the grapes’ rich content of vitamins, fiber, and antioxidant compounds, such as polyphenols. To determine if resveratrol (RES) present in grape extracts is responsible for these benefits, we conducted a study on the effects of red grape skin extract (GSKE), seed extract (GSEE), and RES on sleep patterns, amyloid-beta (Aβ) deposition, neuronal excitability, and lifespan in aDrosophilamodel expressing Aβ42. Aβ42 flies experienced significant sleep fragmentation at night, yet their overall sleep duration was unaffected. Dietary GSKE significantly enhanced sleep duration and mitigated sleep fragmentation in these flies, whereas GSEE only increased the duration of sleep bouts during the day. RES demonstrated a similar effect, albeit to a lesser extent compared to GSKE. All three dietary interventions led to a reduction in Aβ42 levels and an extension of the lifespan in Aβ42 flies, with GSEE showing the least pronounced effects. Furthermore, GSEE and RES were able to reverse the hyperexcitability of mushroom body neurons (MBNs) caused by Aβ42 expression. These results suggest that GSKE and RES are potent promoters of sleep and have the potential to ameliorate sleep disturbances. Additionally, the study highlights that other bioactive component in GSKE, beyond RES, may contribute to its diverse pharmacological activities, which could differ from those of GSEE or RES alone. This underscores the multifaceted nature of grape extracts and their potential therapeutic applications in addressing sleep disorders and neurodegenerative conditions associated with Aβ deposition.
Neurophysiological correlates of cortical hierarchy across the lifespan
Authors: Fehring Jana , Balestrieri Elio , Focke Niels , Dannlowski Udo , Stier Christina , Gross Joachim
Published: July 2024

The brain processes information along a hierarchical structure, forming a gradient of cortical hierarchy from sensorimotor areas to transmodal areas. Here, we aim to understand which aspects of neural dynamics characterize this gradient and whether the respective spatial distribution varies across the lifespan. Therefore, we extracted neurophysiological features from magnetoencephalography recordings in 350 participants between 18 and 88 years during rest. Among traditional features related to the power spectrum, delta power (1-4 Hz) showed the most robust association with cortical hierarchy, increasing along this axis. Beyond traditional features, we employed comprehensive time-series characterization and identified a novel hierarchy-sensitive feature capturing the variability of the signal's mean over time. This feature increases along the cortical hierarchy, suggesting that higher-level brain areas exhibit more dynamic and context-dependent activity patterns. Furthermore, we highlight changes in the gradient of brain dynamics across the lifespan. Alpha power distribution, for instance, exhibits a posterior-anterior gradient in young adults that becomes less pronounced with increasing age. Further, the change of the autocorrelation and auto mutual information function along the cortical hierarchy is heavily modulated by age. These findings reveal simple but robust neurophysiological markers of cortical hierarchy and highlight the dynamic nature of the brain's organization throughout life.
Emergence and maintenance of modularity in neural networks with Hebbian and anti-Hebbian inhibitory STDP
Authors: Bergoin Raphaël , Torcini Alessandro , Deco Gustavo , Quoy Mathias , Zamora-López Gorka
Published: July 2024

The modular and hierarchical organization of the brain is believed to support the coexistence of segregated (specialization) and integrated (binding) information processes. A relevant question is yet to understand how such architecture naturally emerges and is sustained over time, given the plastic nature of the brain's wiring. Following evidences that the sensory cortices organize into assemblies under selective stimuli, it has been shown that stable neuronal assemblies can emerge due to targeted stimulation, embedding various forms of synaptic plasticity in presence of homeostatic and/or control mechanisms. Here, we show that simple spike-timing-dependent plasticity (STDP) rules, based only on pre- and post-synaptic spike times, can also lead to the stable encoding of memories in the absence of any control mechanism. We develop a model of spiking neurons, trained by stimuli targeting different sub-populations. The model satisfies some biologically plausible features: (i) it contains excitatory and inhibitory neurons with Hebbian and anti-Hebbian STDP; (ii) neither the neuronal activity nor the synaptic weights are frozen after the learning phase. Instead, the neurons are allowed to fire spontaneously while synaptic plasticity remains active. We find that only the combination of two inhibitory STDP sub-populations allows for the formation of stable modules in the network, with each sub-population playing a distinctive role. The Hebbian sub-population controls for the firing activity, while the anti-Hebbian neurons promote pattern selectivity. After the learning phase, the network settles into an asynchronous irregular resting-state. This post-learning activity is associated with spontaneous memory recalls which turn out to be fundamental for the long-term consolidation of the learned memories. Due to its simplicity, the introduced model can represent a test-bed for further investigations on the role played by STDP on memory storing and maintenance.
Large-Scale Maps of Altered Cortical Dynamics in Early-Stage Psychosis Are Related to GABAergic and Glutamatergic Neurotransmission
Authors: Arazi Ayelet , Toso Alessandro , Grent-‘t-Jong Tineke , Uhlhaas Peter J. , Donner Tobias H.
Published: July 2024

Psychotic disorders present a challenge for research and clinical practice. Their pathogenesis is poorly understood, symptoms vary widely between patients, and there is a lack of objective biomarkers. Evidence points to a distributed nature of the underlying synaptic alterations in the cerebral cortex. Using magnetoencephalography source imaging, we mapped alterations of neural population dynamics in psychosis across the human cortex. Individuals with early-stage psychosis exhibited characteristic patterns of changes in neural dynamics, in opposite directions for different cortical areas. These patterns were similar for first-episode psychosis and clinical high-risk for psychosis. Different components of these large-scale patterns resembled the effects produced in the healthy brain by pharmacological manipulations of either GABA-A or glutamate (NMDA) receptors. The expression of the GABA-A-component in first-episode psychosis patients was related to positive symptoms, and the expression of the NMDA-component to negative symptoms. Our study opens a window on the large-scale pathophysiology of psychosis.

Teaser

Cortex-wide changes in neural dynamics in early-stage psychosis relate to GABA-A or NMDA receptors and clinical symptoms.
A Mathematical Exploration of SDH-b Loss in Chromaffin Cells
Authors: Vera-Sigüenza Elías , Rana Himani , Nashebi Ramin , Cloete Ielyaas , Kl’učková Katarína , Spill Fabian , Tennant Daniel A.
Published: July 2024

The succinate dehydrogenase (SDH) is a four-subunit enzyme complex (SDH-a, SDH-b, SDH-c, and SDH-d) central to cell carbon metabolism. The SDH bridges the tricarboxylic acid cycle to the electron transport chain. A pathological loss of the SDH-b subunit leads to a cell-wide signalling cascade that shifts the cell’s metabolism into a pseudo-hypoxic state akin to the so-called Warburg effect (or aerobic glycolysis). This trait is a hallmark of phaeochromocytomas, a rare tumour arising from chromaffin cells; a type of cell that lies in the medulla of the adrenal gland.

In this study, we leverage the insights from a mathematical model constructed to underpin the metabolic implications of SDH-b dysfunction in phaeochromocytomas. We specifically investigate why chromaffin cells seemingly have the ability to maintain electron transport chain’s (ETC) Complex I function when confronted with the loss of the SDH-b subunit while other cells do not. Our simulations indicate that retention of Complex I is associated with cofactor oxidation, which enables cells to manage mitochondrial swelling and limit the reversal of the adenosine triphosphate (ATP) synthase, supporting cell fitness, without undergoing lysis. These results support previous hypotheses that point at mitochondrial proton leaks as a critical factor of future research. Moreover, the model asserts that control of the proton gradient across the mitochondrial inner membrane is rate-limiting upon fitness management of SDH-b deficient cells.
Generation and application of novel hES cell reporter lines for the differentiation and maturation of hPS cell-derived islet-like clusters
Authors: Zanfrini Elisa , Bandral Manuj , Jarc Luka , Ramirez-Torres Maria Alejandra , Pezzolla Daniela , Kufrin Vida , Rodriguez-Aznar Eva , Avila Ana Karen Mojica , Cohrs Christian , Speier Stephan , Neumann Katrin , Gavalas Anthony
Published: July 2024

The significant advances in the differentiation of human pluripotent stem (hPS) cells into pancreatic endocrine cells, including functional β-cells, have been based on a detailed understanding of the underlying developmental mechanisms. However, the final differentiation steps, leading from endocrine progenitors to mono-hormonal and mature pancreatic endocrine cells, remain to be fully understood and this is reflected in the remaining shortcomings of the hPS cell-derived islet cells (SC-islet cells), which include a lack of β-cell maturation and variability among different cell lines. Additional signals and modifications of the final differentiation steps will have to be assessed in a combinatorial manner to address the remaining issues and appropriate reporter lines would be useful in this undertaking.

Here we report the generation and functional validation of human pluripotent stem cell reporter lines that can monitor the generation of INS+and GCG+cells and their resolution into mono-hormonal cells (INSeGFP, INSeGFP/ GCGmCHERRY) as well as β-cell maturation (INSeGFP/ MAFAmCHERRY) and function (INSGCaMP6). The reporter hPS cell lines maintained strong and widespread expression of pluripotency markers and differentiated efficiently into definitive endoderm and pancreatic progenitor (PP) cells. PP cells from all lines differentiated efficiently into islet cell clusters that robustly expressed the corresponding reporters and contained glucose-responsive, insulin-producing cells.

To demonstrate the applicability of these hES cell reporter lines in a high-content live imaging approach for the identification of optimal differentiation conditions, we adapted our differentiation procedure to generate SC-islet clusters in microwells. This allowed the live confocal imaging of multiple SC-islets for a single condition and, using this approach, we found that the use of the N21 supplement in the last stage of the differentiation increased the number of monohormonal β-cells without affecting the number of α-cells in the SC-islets.

The hPS cell reporter lines and the high-content live imaging approach described here will enable the efficient assessment of multiple conditions for the optimal differentiation and maturation of SC-islets.
Human FASTK preferentially binds single-stranded and G-rich RNA
Authors: Dawidziak Daria M. , Dzadz Dawid A. , Kuska Mikołaj I. , Kanavalli Madhuri , Klimecka Maria M. , Merski Matthew , Bandyra Katarzyna J. , Górna Maria W.
Published: July 2024

Fas-activated serine/threonine kinase (FASTK) is the founding member of the FASTKD protein family, which was shown to regulate the fate of mRNA molecules on multiple levels. The mitochondrial variant of FASTK co-localizes with mitochondrial RNA granules and regulates degradation of mitochondrial mRNAs, whereas the cytoplasmic and nuclear forms of FAST are involved in regulation of alternative splicing, cytoplasmic RNA granule formation and mRNA translation. Despite these multiple roles of FASTK in mRNA biology, the exact rules of RNA recognition by this protein remained undetermined. Here, we demonstrate direct RNA binding by purified human FASTK and show its preference for single-stranded G-rich sites and RNA G-quadruplexes. Addition of FASTK alone was sufficient to achieve protection of mitochondrial mRNAs from degradation by the degradosome. Structural characterization by SAXS showed that FASTK in solution is a monomer with an extended conformation. Point mutagenesis studies supported the structural predictions of an exposed RNA-binding interface in the central helical region, preceded by a smaller, flexibly attached, helical N-terminal domain. We provide the first such extensivein vitrocharacterization of the RNA binding properties for a representative of the FASTKD protein family, and suggest how these intrinsic properties may underly FASTK function in mRNA metabolism.
Polymer physics models reveal structural folding features of single-molecule gene chromatin conformations
Authors: Conte Mattia , Abraham Alex , Esposito Andrea , Yang Liyan , Gibcus Johan H. , Parsi Krishna M. , Vercellone Francesca , Fontana Andrea , Pierno Florinda Di , Dekker Job , Nicodemi Mario
Published: July 2024

Here, we employ polymer physics models of chromatin to investigate the 3D folding of a 2Mb wide genomic region encompassing the humanLTN1gene, a crucial DNA locus involved in key cellular functions. Through extensive Molecular Dynamics simulations, we reconstruct in-silico the ensemble of single-moleculeLTN13D structures, which we benchmark against recent in-situ Hi-C 2.0 data. The model-derived single molecules are then used to predict structural folding features at the single-cell level, providing testable predictions for super-resolution microscopy experiments.
Cortical layer-specific and cell type-specific dendritic expression of Arc (Arg 3.1) in anin vitromodel of slow-wave sleep
Authors: Hartnell Iain J. , Simon Anna , Hall Stephen P. , Ducotterd Fiona , Whittington Miles A. , Chawla Sangeeta
Published: July 2024

An abundance of evidence shows sleep homeostatically regulates synaptic plasticity and memory consolidation but the underlying molecular regulators of this important function of sleep have been difficult to directly elucidate. Arc is an immediate early gene that has a fundamental role in several aspects of synaptic plasticity including regulation and maintenance. Using a physiological brain slice model of slow-wave sleep, here we show that Arc protein has a characteristic spatial and cell-type specific distribution during persistent sleep-related delta oscillations in neocortical slices, which may correlate with aspects of sleep-dependent regulation of synaptic plasticity in cortical regions. In delta oscillating slices, Arc is highly expressed in layer 2/3 dendrites of the primary and secondary association cortex and this dendritic localisation is specific to intrinsically bursting cells (IB) whose cell bodies are in layer 5. Moreover, Arc immunopositive dendrites are clustered together arranged in a quasi hexagonal arrangement with a spacing of ∼ 50 µm between clusters. The cytoarchitectural distribution of Arc across the association cortex has implications for the mechanisms of sleep and for the synaptic homeostasis hypothesis regarding the function of sleep.
Constraining MeV to 10 GeV Majorons by big bang nucleosynthesis
Authors: Chang Sanghyeon , Ganguly Sougata , Jung Tae Hyun , Park Tae-Sun , Shin Chang Sub
Published: July 2024

We estimate the big bang nucleosynthesis (BBN) constraint on the majoron in the mass range between 1 MeV to 10 GeV which dominantly decays into the standard model neutrinos. When the Majoron lifetime is shorter than 1 sec, the injected neutrinos mainly heat up background plasma, which alters the relation between photon temperature and background neutrino temperature. For a lifetime longer than 1 sec, most of the injected neutrinos directly contribute to the protons-to-neutrons conversion. In both cases, deuterium and helium abundances are enhanced, while the constraint from the deuterium is stronger than that from the helium. Li7 abundance gets decreased as a consequence of additional neutrons, but the parameter range that fits the observed Li7 abundance is excluded by the deuterium constraint. We also estimate other cosmological constraints and compare them with the BBN bound.

Published by the American Physical Society
2024
Derivation of the nonequilibrium generalized Langevin equation from a time-dependent many-body Hamiltonian
Authors: Netz Roland R.
Published: July 2024

It has become standard practice to describe systems that remain far from equilibrium even in their steady state by Langevin equations with colored noise which is chosen independently from the friction contribution. Since these Langevin equations are typically not derived from first-principle Hamiltonian dynamics, it is not clear whether they correspond to physically realizable scenarios. By exact Mori projection in phase space we derive the nonequilibrium generalized Langevin equation (GLE) for an arbitrary phase-space dependent observable A from a generic many-body Hamiltonian with a time-dependent external force h(t) acting on the same observable A. This is the same Hamiltonian from which the standard fluctuation-dissipation theorem is derived, which reflects the generality of our approach. The observable A could, for example, be the position of an atom, of a molecule or of a macroscopic object, the distance between two such entities or a more complex phase-space function such as the reaction coordinate of a chemical reaction or of the folding of a protein. The Hamiltonian could, for example, describe a fluid, a solid, a viscoelastic medium, or even a turbulent inhomogeneous environment. The GLE, which is a closed-form equation of motion for the observable A, is obtained in explicit form to all orders in h(t) and without restrictions on the type of many-body Hamiltonian or the observable A. If the dynamics of the observable A corresponds to a Gaussian process, the resultant GLE has a similar form as the equilibrium Mori GLE, and in particular the friction memory kernel is given by the two-point autocorrelation function of the sum of the complementary and the external force h(t). This is a nontrivial and useful result, as many observables that characterize nonequilibrium systems display Gaussian statistics. For non-Gaussian nonequilibrium observables correction terms appear in the GLE and in the relation between the force autocorrelation and the friction memory kernel, which are explicitly given in terms of cubic correlation functions of A. Interpreting the external force h(t) as a stochastic process, we derive nonequilibrium corrections to the fluctuation-dissipation theorem and present methods to extract all GLE parameters from experimental or simulation time-series data, thus making our nonequilibrium GLE a practical tool to study and model general nonequilibrium systems.

©2024 American Physical Society
2024
American Physical Society
Swap-test interferometry with biased qubit noise
Authors: Černotík Ondřej , Pietikäinen Iivari , Puri Shruti , Girvin S. M. , Filip Radim
Published: July 2024

The Mach-Zehnder interferometer is a powerful device for detecting small phase shifts between two light beams. Simple input states, such as coherent states or single photons, can reach the standard quantum limit of phase estimation, while more complex states can be used to reach Heisenberg scaling; the latter, however, require challenging preparation and measurement strategies. The quest for highly sensitive phase estimation therefore calls for interferometers with nonlinear devices which would make the preparation of these complex states more efficient. Here, we show that the Heisenberg scaling can be recovered with simple input states (including Fock and coherent states) when the linear mirrors in the interferometer are replaced with controlled-swap gates and measurements on auxiliary qubits. These swap tests project the input Fock and coherent states onto NOON and entangled coherent states, respectively, and allow optimal or near-optimal measurements, leading to improved sensitivity to small phase shifts in one of the interferometer arms. We analyze auxiliary qubit errors in detail, showing that biasing the qubit towards phase flips offers a great advantage, and perform thorough numerical simulations of a possible implementation in circuit quantum electrodynamics with an auxiliary Kerr-cat qubit. Our results thus present a viable approach to phase estimation approaching Heisenberg-limited sensitivity and demonstrate potential advantages of using biased-noise qubits in quantum metrology.

Published by the American Physical Society
2024
Multicritical dissipative phase transitions in the anisotropic open quantum Rabi model
Authors: Lyu Guitao , Kottmann Korbinian , Plenio Martin B. , Hwang Myung-Joong
Published: July 2024

We investigate the nonequilibrium steady state of the anisotropic open quantum Rabi model, which exhibits first-order and second-order dissipative phase transitions upon varying the degree of anisotropy between the coupling strengths of rotating and counter-rotating terms. Using both semiclassical and quantum approaches, we find a rich phase diagram resulting from the interplay between the anisotropy and the dissipation. First, there exists a bistable phase where both the normal and superradiant phases are stable. Second, there are multicritical points where the phase boundaries for the first- and second-order phase transitions meet. We show that a new set of critical exponents governs the scaling of the multicritical points. Finally, we discuss the feasibility of observing the multicritical transitions and bistability using a pair of trapped ions where the anisotropy can be tuned by controlling the intensity of the Raman transitions. Our study enlarges the scope of critical phenomena that may occur in finite-component quantum systems, which could be useful for applications in critical quantum sensing.

Published by the American Physical Society
2024
Teaching social support to promote inclusive physical activity for people with autism
Authors: Bassette Laura Anne , Kujawski Maddie , Donges Emma
Published: July 2024

Purpose

Previous research found that when exercise partners provided social support to each other, both participants engaged in higher levels of activity (Gellert et al., 2011). These results suggest that there may be benefits to providing inclusive physical activity (PA) programming to individuals with autism; however, little research has explored specific strategies. The purpose of this study is to explore the use of a behavioral intervention consisting of visual social stories and additional intervention components (i.e. prompting, checklists) to teach adolescents/young adults with autism and their workout partners without disabilities to provide social support to one another during partnered PA.

Design/methodology/approach

A multiple probe across dyads was used to explore the effects of the intervention on social support (i.e. verbal encouragement and feedback).

Findings

The results indicate the treatment was effective during the intervention phase. When partners and settings changed during generalization, results were maintained in all but one participant.

Originality/value

Areas for future research and implications for practice to support inclusive PA for autistics are discussed.
The influence of manufacturer encroachment on the supply chain: the conditional role of traditional retailer retail service investment
Authors: Zhang Zijian , Xu Yuanying , Meng Lijiao , Luo Renjie , Huang Jun
Published: July 2024

Purpose

This paper investigates the dual interactive effects of manufacturer encroachment on the supply chain and retailer provision of retail services.

Design/methodology/approach

Consider a supply chain dominated by manufacturers, retailers, and e-commerce platforms, with the manufacturers selling the same product online and offline. Utilizing Stackelberg’s game theory, examples of wholesale and retail prices and profits of participants in the supply chain under different channels are analyzed. An effective encroachment strategy for manufacturers facing different retail service investment strategies of traditional retailers is given.

Findings

When traditional retailers do not invest in retail services, they will lose more profit due to competition with the manufacturer. At this time, the retailer does not want the manufacturer to encroach. The traditional retailer’s investment in retail services will enhance its and the manufacturer’s profits, incentivizing the manufacturer to pursue an aggressive expansion strategy.

Originality/value

(1) Considers a situation where the selling efficiency of the manufacturer is lower than that of the traditional retailer. (2) The interaction between traditional retailers’ retail service investment strategies and manufacturers’ encroachment strategies is investigated where the manufacturer is the dominant player. The three modes of online direct sales, resale, and third-party platform agency are compared to provide a basis for decision-making on different types of manufacturers’ encroachment. (3) Offline retail services not only directly increase sales in the offline market but also indirectly have a negative effect on the online market.
Social media influencer marketing and economic performance in the Spanish wine industry: unravelling the role of corporate social legitimacy
Authors: Martínez-Falcó Javier , Sánchez-García Eduardo , Marco-Lajara Bartolomé , Fuentes-Fernández Rosana
Published: July 2024

Purpose

This research focuses firstly on the impact of Social Media Influencer Marketing (SMIM) on the Economic Performance (EP) of Spanish wineries, and secondly on the mediating effect of Corporate Social Legitimacy (CSL) on this main relationship (SMIM-EP). Age, size and Protected Designation of Origin (PDO) membership are used to increase the precision of the cause-effect relationships examined.

Design/methodology/approach

The study proposes a conceptual model based on previous studies, which is tested using structural equations (PLS-SEM) with data collected from 196 Spanish wineries between September 2022 and January 2023.

Findings

The results reveal a positive and significant relationship between the development of SMIM and the EP of Spanish wineries, as well as the partial mediation of CSL in the SMIM-EP relationship.

Originality/value

The uniqueness of this study can be attributed to several factors. First, it enhances the understanding and knowledge of the benefits associated with SMIM development in the winemaking context. Second, no previous research has conducted an empirical study on the development of SMIM as a catalyst for EP in the context of Spanish wineries. Third, to the authors' knowledge, no previous study has examined the mediating role of CSL in the SMIM-EP relationship, thus representing an opportunity to advance scientific knowledge related to SMIM.
Analyzing barriers to sustainable healthcare waste disposal: a hybrid decision-making framework
Authors: Kumar Santosh , Tarei Pradeep Kumar , Swarnakar Vikas
Published: July 2024

Purpose

In the recent post-pandemic era, the globe has been anxious for the sustainable disposal of healthcare waste to protect public health, protect the environment and enhance future preparedness. Developing countries, in particular, have struggled to dispose of healthcare waste (HCW) to eradicate the hazardous effects of medical waste generated during and after the deadly COVID-19 pandemic. Hence the purpose of the research paper is to develop a hybrid decision-making framework to identify various barriers for sustainable disposal of healthcare waste use of Grey-Decision Making Trial and Evaluation Laboratory (G-DEMATEL) and Analytical Network Process (ANP).

Design/methodology/approach

A hybrid framework of Grey-Decision Making Trial and Evaluation Laboratory (G-DEMATEL) and Analytical Network Process (ANP) has been used to rank barriers and sub-barriers in the disposal of healthcare waste.

Findings

The study’s findings suggest that lack of segregation practices, absence of green procurement policy, obsolete technologies and resistance to adopting change management are the topmost causal barriers influencing the remaining barriers. Lack of commitment among healthcare administrations, lack of standard performance measures and resistance to adopting change appear to be the topmost crucial barriers.

Practical implications

The study’s finding enables all stakeholders to prioritize the barriers systematically for better performance and save resources during the process. The policymakers can use the results to design a clear regulatory framework.

Originality/value

The literature has highlighted the factors and their association with the disposal of healthcare waste mainly in isolation. The results are validated against the Grey-Analytical Hierarchy Process (G-AHP) to ensure the robustness of the proposed framework. This paper is one of the preliminary attempts to propose a framework of the interrelationships of the factors that have a direct role in survival for management education.
National culture and corporate investment: does uncertainty matter?
Authors: Al Mubarak Ahmed , Giouvris Evangelos
Published: July 2024

Purpose

Our purpose is to explore how culture’s impact on investment is depending on uncertainty levels.

Design/methodology/approach

This study investigates the interplay between national culture, uncertainty, and corporate investment decisions. Focusing on the uncertainty avoidance dimension (HUA) from Hofstede’s culture framework and utilizing the World Uncertainty Index (WUI) as a measure of uncertainty, this research explores how culture’s impact on investment is depending on uncertainty levels.

Findings

Our results reveal that high HUA countries lower long-term investment during periods of heightened uncertainty, particularly in riskier investments like R&D, rather than capital expenditure. This relation is more pronounced for smaller firms. The findings suggest that HUA is associated with less risk taking, primarily when uncertainty is high. Furthermore, we demonstrate that the interaction between HUA and uncertainty exerts more significant and consistent effects on corporate investment than other cultural dimensions, religion, and various formal institutions, contrary to prevailing literature.

Originality/value

This study looks at the relationship between national culture and corporate investment under ambiguity, and what are the implications for risk taking. If national culture is related to riskier investments, such as R&D, relative to safer investments, like capital expenditure this would imply that risk taking is explaining the relationship between national culture and corporate investment. This relation should be clear during uncertain times. This is the first study to include the moderating effects of the level of uncertainty on the relation between national culture and corporate investment (or financial decisions in general).
Mamaearth IPO: the pricing dilemma of a startup
Authors: Bhatia Shikha , Dhamija Sanjay
Published: July 2024

Learning outcomes

After working through the case and assignment questions, students will be able to recognize essential considerations for the initial public offerings (IPO) decision, compare different types of fundraising options for startups, evaluate the free pricing regime for IPO pricing, examine the pricing process of IPOs, explore the issue of valuation of IPOs and assess the decision choices of the founder regarding IPO given the trade-offs and market conditions.

Case overview/synopsis

The case study explores the dilemma of Ghazal Alagh, the co-founder and chief innovation officer of Mamaearth, a direct-to-consumer babycare and skincare unicorn, regarding its IPO decision. Mamaearth had filed the draft offer document with SEBI in December 2022, and Ghazal was busy engaging with the investment bankers for the upcoming IPO. However, the weak market sentiments and shelving of IPO plans by many startups were forcing her to think about facing the possibility of postponing the IPO or continuing the IPO process but at lower valuations. The case study provides an opportunity to explore a startup’s financing choices. It allows for discussion of various IPO challenges from the perspectives of founders, venture investors, regulators, investment bankers and new IPO investors.

Complexity academic level

This case study is best suited for senior undergraduate- and graduate-level business school students in courses focusing on entrepreneurship, corporate finance, financial management, strategic management and investment banking.

Subject code

CSS1: Accounting and finance.

Supplementary materials

Teaching notes are available for educators only.
Readiness of Pakistani journals for open access publishing
Authors: Raza Muhammad Zahid , Rafiq Muhammad , Soroya Saira Hanif
Published: July 2024

Purpose

This study was designed to discover the readiness of the higher education commission (HEC)-recognized journals of Pakistan in terms of human, financial and technological resources, technical expertise, institutional support, availability of open access (OA) policy, availability of guidance and training, willingness, motivation and so on for OA journal publishing and to expose the challenges in OA journal publishing.

Design/methodology/approach

A quantitative research approach was used and a structured questionnaire was developed to meet the objectives of this study. A survey method was used to collect data from the editors of all 329 HEC-recognized journals in Pakistan.

Findings

The respondents of all the HEC-recognized journals of Pakistan are neutral and are not of the view that they have sufficient financial, human, technological/infrastructural resources and technical expertise to continue/initiate an OA journal publishing. ‘No academic reward’; and ‘no monetary reward for the editorial staff’ are both enormous challenges for OA journal publishing. The perceived challenges of OA have a negative impact on readiness for OA publishing. The readiness level of the respondents of the OA journals is higher as compared to the readiness level of the respondents of non-OA journals.

Research limitations/implications

This study covered the lists of HEC-recognized journals of 2019. More studies may be conducted based on updated lists of HEC-recognized journals. Qualitative studies may also be conducted to discover the readiness of the HEC-recognized journals of Pakistan for OA journal publishing.

Originality/value

This study is the first comprehensive study on this phenomenon and is an effort to fill this gap to invigorate scholarly literature. It may attract the attention of policymakers, funding bodies, parent institutions of the journals and the HEC regarding the readiness of journals in terms of financial, human, technological/infrastructural resources, technical expertise of the journals and challenges of journals to prompt the OA journal publishing paradigm.
Thriving in change: examining the influence of organizational sustainability on employee performance in the post-COVID landscape
Authors: Junça Silva Ana , Costa Sofia
Published: July 2024

Purpose

The economic, financial and social crisis has heightened researchers' interest in the importance of organizational sustainability and resources (e.g. work engagement and psychological capital) for performance. Despite some studies demonstrating the significance of resources, such as work engagement and psychological capital, for workers’ performance, there is limited knowledge regarding the role of organizational sustainability practices (OSP) in the relationship mentioned above. Therefore, this study drew upon the social identity theory to conceptualize and test the mediating role of work engagement in the relationship between OSP and performance (both task and adaptive). Based on the conservation of resources theory, it was hypothesized that a worker's resource – psychological capital – would moderate the indirect relationship between social responsibility practices and performance (both task and adaptive).

Design/methodology/approach

To test the proposed model, 304 adults participated in a two-wave study.

Findings

The results supported the hypotheses, revealing that OSP had a positive and significant relationship with task and adaptive performance, occurring through work engagement. Furthermore, the indirect relationship between OSP and performance task and adaptive through work engagement was moderated by psychological capital, such that the relationship became stronger for workers with lower levels of psychological capital.

Originality/value

The relevance of this research lies in its ability to identify the conditions and mechanisms in which corporate social responsibility initiatives are most effective, thereby enabling a more nuanced application of these practices across different sectors and organizational cultures. This study's theoretical and practical implications may assist organizations in devising strategies for implementing social responsibility practices to enhance their outcomes.
Creating a religious identity and impression management by Islamic banks
Authors: Maali Bassam Mohammad , Hassan M. Kabir , Rashid Mamunur
Published: July 2024

Purpose

Islamic banks (IBs) place significant importance on their religious identity, prompting the utilization of impression management (IM) strategies to emphasize such identity. This paper aims to discuss the motivations behind using IM in the creation of religious identity by IBs, and to explore the use of religious symbols and language as a form of religious rhetoric. It is argued that to counteract the threats to their religious identity, IBs use IM techniques, predominantly through the inclusion of religious symbols and rhetoric.

Design/methodology/approach

An empirical exploratory study, using content analysis, was conducted on the annual reports of the largest IBs for the year 2022. The analyses involved a total of 39 banks based on a filtered list from The Banker’s Top Islamic Financial Institutions of 2022. A manual content analysis was undertaken to extract religious symbols, images and contents.

Findings

The findings reveal the use of IM techniques that emphasize the religious identity of these banks. Notably, IBs consistently reaffirm their commitment to Sharia compliance and disclose their contributions to Zakah. In addition, the analysis reveals the incorporation of Quranic verses, religious iconographic images and other religious rhetoric statements in the annual reports of many IBs.

Research limitations/implications

The analysis concludes that the assertion by IBs that their guiding principles are rooted in Islamic values are supported by the religious terminology and imagery embedded in their annual reports. Alongside mere religious symbolism, the terms and images are integral part of the corporate identity of the Islamic that not only sends persuasive signals to stakeholders but also help build an impression on the activities of the IBs.

Originality/value

IM has been a key objective and strategy of companies. This study aimed at exploring whether and how IBs used religious symbolism as an integral part of IM and corporate identity.
The contribution of digitization to successful international expansion: lessons from Decathlon’s strategic movements
Authors: Rebière Philippe , Braun Olivier
Published: July 2024

Purpose

The purpose of this paper is to explain to what extent digitization is an opportunity to international development of the firm by drawing on the international expansion of the French Decathlon group. The retailer and manufacturer have adopted a number of interesting strategies, following “specific movements,” as the authors have noted.

Design/methodology/approach

Data were collected using the Europress database. The authors compiled press articles about the development of the Decathlon company and discussed the various stages of the brand's growth to enhance understanding and propose refinements to the current knowledge of companies' internationalization.

Findings

The findings support the idea that digitization of the distribution and production chain reduces transaction costs and accelerates the conquest of market share. Digitization brings new experiential knowledge to companies and facilitates internationalization. Decathlon's success lies not in its resources or in the art of managing its internal capabilities, but rather in the ability to combine organizational resources with key external capabilities (development of technological partnerships).

Originality/value

The originality of this research lies in the logic of deepening the steps of companies’ internationalization integrating new technologies that shift current comprehension of this phenomenon. After the COVID-19 period, digitization is accelerated and represent threats and probably opportunities to break down barriers to companies’ abroad expansion.