bluuebunny/crossref_metadata_2025 huggingface dataset:
The genetic history of Portugal over the past 5,000 years
Authors: Roca-Rada Xavier , Davidson Roberta , Williams Matthew P. , Ravishankar Shyamsundar , Collen Evelyn , Haarkötter Christian , Taufik Leonard , Carvalho António Faustino , Villalba-Mouco Vanessa , Cuesta-Aguirre Daniel R. , Tente Catarina , Monge Calleja Álvaro M. , MacRoberts Rebecca Anne , Melo Linda , Purnomo Gludhug A. , Souilmi Yassine , Tobler Raymond , Cunha Eugénia , Tereso Sofia , Matos Vítor M. J. , Fernandes Teresa Matos , Mauer Anne-France , Silva Ana Maria , Carvalho Pedro C. , Llamas Bastien , Teixeira João C.
Published: September 2024

Background

Recent ancient DNA studies uncovering large-scale demographic events in Iberia have focused primarily on Spain, with limited reports for Portugal, a country located at the westernmost edge of continental Eurasia. Here, we introduce the largest collection of ancient Portuguese genomic datasets (n = 68) to date, spanning 5,000 years, from the Neolithic to the 19thcentury.

Results

We found evidence of patrilocality in Neolithic Portugal, with admixture from local hunter-gatherers and Anatolian farmers, and persistence of Upper Paleolithic Magdalenian ancestry. This genetic profile persists into the Chalcolithic, reflecting diverse local hunter- gatherer contributions. During the Bronze Age, local genetic ancestry persisted, particularly in southern Iberia, despite influences from the North Pontic Steppe and early Mediterranean contacts. The Roman period highlights Idanha-a-Velha as a hub of migration and interaction, with a notably diverse genetic profile. The Early Medieval period is marked by Central European ancestry linked to Suebi/Visigoth migrations, adding to coeval local, African, and Mediterranean influences. The Islamic and Christian Conquest periods show strong genetic continuity in northern Portugal and significant African admixture in the south, with persistent Jewish and Islamic ancestries suggesting enduring influences in the post-Islamic period.

Conclusions

This study represents the first attempt to reconstruct the genetic history of Portugal from the analysis of ancient individuals. We reveal dynamic patterns of migration and cultural exchange across millennia, but also the persistence of local ancestries. Our findings integrate genetic information with historical and archaeological data, enhancing our understanding of Iberia’s ancient heritage.
The Molecular Toll Pathway Repertoire in Anopheline Mosquitoes
Authors: Rhodes Victoria L. , Waterhouse Robert M. , Michel Kristin
Published: September 2024

Innate immunity in mosquitoes has received much attention due to its potential impact on vector competence for vector-borne disease pathogens, including malaria parasites. The nuclear factor (NF)-κB-dependent Toll pathway is a major regulator of innate immunity in insects. In mosquitoes, this pathway controls transcription of the majority of the known canonical humoral immune effectors, mediates anti-bacterial, anti-fungal and anti-viral immune responses, and contributes to malaria parasite killing. However, besides initial gene annotation of putative Toll pathway members and genetic analysis of the contribution of few key components to immunity, the molecular make-up and function of the Toll pathway in mosquitoes is largely unexplored. To facilitate functional analyses of the Toll pathway in mosquitoes, we report here manually annotated and refined gene models of Toll-like receptors and all putative components of the intracellular signal transduction cascade across 19 anopheline genomes, and in two culicine genomes. In addition, based on phylogenetic analyses, we identified differing levels of evolutionary constraint across the intracellular Toll pathway members, and identified a recent radiation of TOLL1/5 within theAn. gambiaecomplex. Together, this study provides insight into the evolution of TLRs and the putative members of the intracellular signal transduction cascade within the genusAnopheles.
Endothelial miR-34a deletion guards against aneurysm development despite endothelial dysfunction
Authors: Kopacz Aleksandra , Kloska Damian , Bar Anna , Targosz-Korecka Marta , Cysewski Dominik , Chlopicki Stefan , Jozkowicz Alicja , Grochot-Przeczek Anna
Published: September 2024

Objectives

Our previous study reported a reciprocal link between NRF2, a stress-responsive cytoprotective transcription factor, and aortic and endothelial cell (EC) ageing. We also found that NRF2 transcriptional knockout (tKO) mice are prone to abdominal aortic aneurysm (AAA) development. Given that miRNA-34a is a marker of ageing, in this study we explored its relationship with NRF2 and its role in vascular function and AAA formation.

Approach and results

The experiments were performed in primary human aortic endothelial cells (HAECs) from young and aged donors and mice devoid of NRF2 transcriptional activity and endothelial miR-34a. The normolipidemic mice were challenged with angiotensin II (Ang II) to develop AAA. We show that premature NRF2-dependent aging of aortic endothelial cells (ECs) depends on miR-34a. Infusion of hypertensive Ang II in mice increases miR-34a in the aortic endothelial layer and serum, especially in mice which develop AAA. Mice deficient in endothelial miR-34a (miR-34aΔEC) display severe EC dysfunction. Despite that, such mice are protected from AAA development, also on the NRF2 tKO background. Ang II infusion increases proliferation of intimal ECs in these mice. The protective effect of endothelial miR-34a deletion on AAA formation is reversed by rapamycin that suppresses EC proliferation. MTA2, but not SIRT1, is a direct target of miR-34a abrogating Ang II-induced EC proliferation.

Conclusions

These findings reveal that AAA development in NRF2 tKO mice relies on endothelial miR-34a overexpression. Deletion of endothelial miR-34a protects mice from AAA despite inducing endothelial cell dysfunction. The fine-tuning of EC proliferation may play a therapeutic role in the treatment of aneurysm.
Interaction between facial expression and color in modulating ERP P3
Authors: Hasegawa Yuya , Tamura Hideki , Nakauchi Shigeki , Minami Tetsuto
Published: September 2024

The relationships between facial expression and color affect human cognition functions such as perception and memory. However, whether these relationships influence attention remains unclear. Additionally, whether facial expressions affect selective attention is unknown; for example, reddish angry faces increase negative social evaluation or emotion intensity, but it is unclear whether selective attention is similarly enhanced. To investigate these questions, we examined whether event-related potentials for faces vary depending on facial expression and color by recording electroencephalography (EEG) data. We conducted an oddball task using stimuli that combined facial expressions (angry, neutral) and facial colors (original, red, green). The participants counted the number of times a rarely appearing target face stimulus appeared among the standard face stimuli. The results indicated that the difference in P3 amplitudes for the target and standard faces depended on the combinations of facial expressions and facial colors; the P3 amplitudes for red angry faces were greater than those for red neutral faces. Additionally, there was no significant main effect or interaction effect of facial expression or facial color on P1 amplitudes for the target, and there were significant main effects of facial expression only on the N170 amplitude. These findings suggest that the intensity of a human’s selective attention to facial expressions varies according to the higher-order semantic processing of the relationship between emotion and color rather than simple facial expression or facial color effects individually. Our results support the idea that red color increases the human response to anger from an EEG perspective.

Significance Statement

It remains unclear whether selective attention to faces is modulated by the relationships between facial expression and color. Using an oddball task and recording EEGs, we showed that the event-related potentials reflecting selective attention are modulated by the interaction between facial expression and facial color, although the interaction was not found at earlier ERP stages. These findings suggest that the intensity of selective attention to facial expressions is influenced more by the interaction between facial expression and facial color than by facial expression or facial color alone and that the interaction occurs as a higher-order processing step than facial expression or color recognition. Our results provide EEG evidence supporting the idea that red color increases the human response to anger.
Structural insight into the nuclear transportation mechanism of PPARγ by Transportin-1
Authors: Toma-Fukai Sachiko , Nakamura Yutaro , Kawamoto Akihiro , Shimizu Hikaru , Hayama Koki , Kojima Ruri , Yoshimura Kanami , Ishii Masaki , Hirose Mika , Teratani Toshiaki , Ohata Shinya , Kato Takayuki , Kamikubo Hironari , Itoh Toshimasa , Tomita Kengo , Shimizu Toshiyuki
Published: September 2024

The spatial and temporal control of protein is essential for normal cellular function. Proteins working in the nucleus have nuclear localization signal (NLS) sequences and are escorted into the nucleus by cognate nuclear transport receptors. A wealth of experimental data about NLS has been accumulated, and nuclear transportation mechanisms are established at the biochemical and structural levels.

The peroxisome proliferator-activated receptors (PPARs) are ligand-dependent transcription factors that control various biological responses. We recently reported that the transportation of PPARγ is mediated by Transportin-1, but PPARγ lacks a typical NLS sequence recognized by Transportin-1. Moreover, the recognition mechanism remains largely unknown.

In this study, we determined the Cryo-EM structure of PPARγ in complex with Transportin-1 and revealed that Transportin-1 gripped the folded DNA binding domain and the Hinge region of PPARγ, indicating that PPARγ recognizes a folded domain with an extended region as a nuclear localization signal, not a canonical unstructured signal sequence, confirmed by the mutation analyses in vitro and in cultured cells. Our study is the first snapshot structure working in nuclear transportation, not in transcription, of PPARγ.
Expansion ofDrosophilahaemocytes using a conditionalGeneSwitchdriver affects larval haemocyte function, but does not modulate adult lifespan or survival from infection
Authors: Hayman Dan J , Morrin Lola M , Halder Sudipta , Phillips Eleanor J , Simons Mirre J P , Evans Iwan R
Published: September 2024

Macrophages are responsible for diverse and fundamental functions in vertebrates. Fruit flies harbour an innate immune system of which the most populous blood cell (haemocyte) type bears striking homology to the vertebrate macrophage. The importance of these cells has been demonstrated previously, where immune and developmental phenotypes have been observed upon haemocyte ablation using pro-apoptotic transgenes driven by theHmlpromoter.

Here we show that, as well as ablatingHml-positive cellsin vivousing the pro-apoptotic transgenebax, we can also increaseHml-positive cell numbers using a constitutively-active form ofras. However, in adults, compared to larvae, total blood cell numbers were not significantly affected by experimental expansion or ablation. This therefore implies the existence of feedback mechanisms which regulate the number of haemocytes.

No effect on lifespan was observed from drivingrasandbaxinHml-positive cells using a conditional genetic system (Hml-GeneSwitch). Using a constitutive driver system, we did observe differences in lifespan, however we attribute this to differences in genetic background that could have led to spurious conclusions. Additionally, no effect of either transgene was observed upon infection with two different bacterial species, although a striking pupal lethality phenotype was observed upon expansion ofHml-positive cells in the context of a self-encapsulation mutant genetic background. The latter confirms that the change inHml-positive cell number does result in a phenotype. The lack of adult phenotypes could be due to the strength of our experimental manipulation or due to compensation via feedback mechanisms that operate to maintain total blood cell numbers. Our study demonstrates the importance of a conditional approach to modulate haemocyte cell numbersin vivowhich allows for more precise study of innate immune system function. This approach could be especially fruitful to uncover the mechanisms that regulate total blood cell numbers across development and ageing.
Targeting the untargeted: Uncovering the chemical complexity of root exudates
Authors: Möller Katrin , Ritter Annalena , Stobinsky Phillip J. , Jensen Kai , Meier Ina C. , Subrahmaniam Harihar Jaishree
Published: September 2024

The chemical complexity of root exudates has garnered significant attention in recent years, yet critical gaps remain in understanding the full scope of root exudate chemical variation across the plant kingdom. To address this, we conducted a systematic review of 57 studies, comprising 124 experiments, aimed at evaluating current methodologies and findings in untargeted root exudate chemical analysis. Our review revealed that hydroponic (44%) and soil-hydroponic hybrid (32%) sampling approaches, primarily utilising water as the collection medium, were the most common experimental setups. Liquid chromatography-mass spectrometry (LC-MS) was the predominant analytical technique used in 54% of the studies, followed by gas chromatography-mass spectrometry (GC-MS) in 31%. The average number of metabolites identified per analysis was 960, though the number of annotated metabolites varied considerably. Shikimates, phenylpropanoids, and carbohydrates were the most frequently identified classes, with their relative abundances varying widely. Several methodological challenges were highlighted, including inconsistencies in sampling techniques, underrepresentation of non-crop plants, and incomplete chemical annotation. To address these limitations, we propose a framework emphasising the need for representative exudate sampling, the use of multiple analytical approaches, the development of advanced bioinformatics tools, and the integration of these findings to enhance our understanding of root exudates and their ecological functions.
Select autosomal dominant DFNA11 deafness mutations activate Myo7A in epithelial cells
Authors: Acharya Prashun , Thapa Garima , Liao Xiayi , Matoo Samaneh , Graves Maura J. , Atallah Sarah Y. , Tipirneni Ashna K. , Nguyen Tram , Chhabra Niki. M. , Maschack Jaden , Herod Mackenzie R. , Ohaezu Favour A. , Robison Alder , Mudaliyar Ashwini , Bharaj Jasvinder , Roeser Nicole , Holmes Katherine , Nayak Vishwaas , Alsayed Rayah , Perrin Benjamin J. , Crawley Scott W.
Published: September 2024

Myosin-7A (Myo7A) is a motor protein crucial for the organization and function of stereocilia, specialized actin-rich protrusions on the surface of inner ear hair cells that mediate hearing. Mutations in Myo7A cause several forms of genetic hearing loss, including autosomal dominant DFNA11 deafness. Despite its importance, the structural elements of Myo7A that control its motor activity within cells are not well understood. In this study, we used cultured kidney epithelial cells to screen for mutations that activate the motor-dependent targeting of Myo7A to the tips of apical microvilli on these cells. Our findings reveal that Myo7A is regulated by specific IQ motifs within its lever arm, and that this regulation can function at least partially independent of its tail sequence. Importantly, we demonstrate that many of the DFNA11 deafness mutations reported in patients activate Myo7A targeting, providing a potential explanation for the autosomal dominant genetics of this form of deafness.
High-efficiency transformation and gene expression inPicosynechococcussp. PCC 7002
Authors: Hren Andrew P. , Abraham Joshua P. , Tumen-Velasquez Melissa P. , Vergara Michael Melesse , Guss Adam M. , Alexander William G. , Pfleger Brian F. , Fox Jerome M. , Eckert Carrie A.
Published: September 2024

Cyanobacteria are promising microbial platforms for a myriad of biotechnological applications, from sustainable biomaterials to photosynthetic chemical production, but still lack the breadth of genetic tools available for more commonly engineered microbes such asEscherichia coli. This study develops genetic tools to enhance the transformation efficiency and heterologous gene expression inPicosynechococcussp. PCC 7002, a fast-growing, halotolerant, and naturally competent strain. Integration of fluorescent reporter cassettes across the genome revealed an integration site that yields a fourfold improvement in gene expression relative to previously reported sites. Protocol optimization and engineered DNA methylation inE. coliincreased transformation efficiency by over tenfold. This work provides an experimental framework for efficient genome editing and metabolic engineering in the model cyanobacterium PCC 7002.
Cortical state contributions to response variability in the early visual cortex: A system identification approach
Authors: Sooriyaarachchi Jinani , Zhan Chang’an , Baker Curtis L.
Published: September 2024

Neurons in the early visual cortex respond selectively to multiple features of visual stimuli, but they respond differently to repeated presentation of the same visual stimulus. Such trial-to-trial response variabilities are often treated as noise and addressed by simple trial-averaging to obtain the stimulus-driven response, though this approach is insufficient to fully remove the response variability. More importantly, there is evidence that response variability may primarily be caused by non-sensory factors, particularly by variations in cortical state.

Here we recorded and analyzed neuronal spiking activity in response to natural images from areas 17 and 18 of cats, along with local population neuronal signals; local field potential (LFP) and multi-unit activity (MUA). We used a variability ratio (VR) measure to quantify the variability of neural responses across trials and two cortical state indicative measures; global fluctuation index (GFI) calculated using MUA and synchrony index (SI) calculated using LFP signals. We propose a compact convolutional neural network model with two parallel pathways, to capture the stimulus- driven activity and the cortical state-driven response variabilities. The stimulus-driven pathway contains a spatiotemporal filter, a parametric rectifier and a Gaussian map and the cortical state-driven pathway contains temporal filters for MUA and LFP. The model parameters are fit to best predict each neuron’s spiking activity.

Single neurons showed highly varying degrees of trial-to-trial response variability, even when recorded simultaneously. The fitted model performed with a significantly higher accuracy in predicting neural responses compared to a basic model with a stimulus-driven pathway alone. The neurons with higher response variability benefited more from the cortical state-driven pathway compared to less variable neurons. These results provide insights to understanding the possibility of trial-to-trial response variabilities emerging as an effect of cortical state dynamics.
The tilt illusion arises from an efficient reallocation of neural coding resources at the contextual boundary
Authors: Zhang Ling-Qi , Mao Jiang , Aguirre Geoffrey K. , Stocker Alan A.
Published: September 2024

The tilt illusion — a bias in the perceived orientation of a center stimulus induced by an oriented surround — illustrates how context shapes visual perception. While the tilt illusion has been the subject of quantitative study for over 85 years, we still lack a comprehensive account of the phenomenon that connects its neural and behavioral characteristics. Here, we demonstrate that the tilt illusion originates from a dynamic change in neural coding precision induced by the surround context. We simultaneously obtained psychophysical and fMRI responses from human subjects while they viewed gratings in the absence and presence of an oriented surround, and extracted sensory encoding precision from their behavioral and neural data. Both measures show that in the absence of a surround, encoding reflects the natural scene statistics of orientation. However, in the presence of an oriented surround, encoding precision is significantly increased for stimuli similar to the surround orientation. This local change in encoding is sufficient to accurately predict the behavioral characteristics of the tilt illusion using a Bayesian observer model. The effect of surround modulation increases along the ventral stream, and is localized to the portion of the visual cortex with receptive fields at the center-surround boundary. The pattern of change in coding accuracy reflects the surround-conditioned orientation statistics in natural scenes, but cannot be explained by local stimulus configuration. Our results suggest that the tilt illusion naturally emerges from a dynamic coding strategy that efficiently reallocates neural coding resources based on the current stimulus context.
Probing the position-dependent optical energy fluence rate in three-dimensional scattering samples
Authors: Akdemir Ozan , Truong Minh Duy , Rates Alfredo , Lagendijk Ad , Vos Willem L.
Published: September 2024

The accurate determination of the position-dependent energy fluence rate of scattered light (which is proportional to the energy density) is crucial to the understanding of transport in anisotropically scattering and absorbing samples, such as biological tissue, seawater, atmospheric turbulent layers, and light-emitting diodes. While Monte Carlo simulations are precise, their long computation time is not desirable. Common analytical approximations to the radiative transfer equation (RTE) fail to predict light transport and could even give unphysical results. Therefore, we experimentally probe the position-dependent energy fluence rate of light inside scattering samples where the widely used P1 and P3 approximations to the RTE fail. The samples are three-dimensional (3D) aqueous suspensions of anisotropically scattering and both absorbing and nonabsorbing spherical scatterers, namely, microspheres (r=0.5µm) with and without absorbing dye. To probe the energy fluence rate, we detect the emission of quantum-dot reporter particles that are excited by the incident light and that are contained in a thin capillary. By scanning the capillary through the sample, we access the position dependence. We present a comprehensive discussion of experimental limitations and of both random and systematic errors. Our observations agree well with the Monte Carlo simulations and the P3 approximation of the RTE with a correction for forward scattering. In contrast, the P1 and the P3 approximations deviate increasingly from our observations, ultimately even predicting unphysical negative energies.

Published by the American Physical Society
2024
Extraction of the microscopic properties of quasiparticles using deep neural networks
Authors: Soloveva Olga , Palermo Andrea , Bratkovskaya Elena
Published: September 2024

We use deep neural networks (DNNs) to obtain the properties of partons in terms of an off-shell quasiparticle description. We aim to infer masses and widths of quasigluons, up/down, and strange (anti)quarks using constraints on the macroscopic thermodynamic observables obtained by the first-principles lattice QCD (lQCD) calculations. In this study we use three independent dimensionless thermodynamic observables from lQCD for minimization as the ratio of entropy density to temperature s/T3, baryon susceptibility χ2B, and strangeness susceptibility χ2S. First, we train our DNN using the DQPM (dynamical quasiparticle model) ansatz for the masses and widths. Furthermore, we use the DNN capabilities to generalize this ansatz, to evaluate which quasiparticle masses and widths are desirable to describe different thermodynamic functions simultaneously. To evaluate consistently the microscopic properties obtained by the DNN in the case of off-shell quarks and gluons, we compute transport coefficients using the spectral function within the Kubo-Zubarev formalism in different setups. In particular, we make a comprehensive comparison in the case of the dimensionless ratios of shear viscosity over entropy density η/s, and electric conductivity over temperature σQ/T, which provide additional constraints for the parameter generalization of the considered model cases. We present the parameter settings found by the DNN which can improve the quasiparticle description of lQCD data on the susceptibility and electric conductivity of strange quarks.

Published by the American Physical Society
2024
Study of angular observables in exclusive semileptonic
Bc
decays
Authors: Patnaik Sonali , Nayak Lopamudra , Sadangi Priyanka , Swain Sanjay , Singh Rajeev
Published: September 2024

In this work, we investigate angular observables such as the longitudinal polarization of charged leptons, τ-polarization, and forward-backward asymmetry in semileptonic Bc decays. Additionally, we provide predictions for lepton flavor violating observables, the R ratios in the decay channels Bc→ηc(J/ψ)lνl and Bc→D(D*)lνl across the entire q2 region. Our analysis is conducted within the relativistic independent quark model, focusing on the potential model-dependent aspects of these observables. We compare our model predictions with existing lattice predictions, highlighting the strong applicability of our framework in describing Bc decays. Considering the forthcoming experimental upgrades and the Run 3 data results on Bc meson decays, rapid confirmation of these quantities could indicate significant discoveries of physics beyond the Standard Model. This may open up new avenues for understanding the complex flavor dynamics in heavy meson decays.

Published by the American Physical Society
2024
ρ
meson magnetic dipole moment from
BaBar

e+e−→π+π−π0π0
cross section measurement
Authors: Rojas Antonio , Toledo Genaro
Published: September 2024

We obtain the value of the magnetic dipole moment of the ρ meson, using data from the collaboration for the e+e−→π+π−2π0 process. The considered center of mass energy range is from 0.9 to 1.8 GeV. We describe the γ*→4π vertex using a vector meson dominance model, including the intermediate resonant contributions relevant at these energies. We find μρ=2.7±0.3 in e/2mρ units. We improve on the previous extracted value, where preliminary data from the same collaboration was used, by considering definite data, better grounded values of the parameters involved, and an explicit gauge invariant description of the process.

Published by the American Physical Society
2024
Theoretical study of the
π+p→pa0+ϕ
reaction
Authors: Xu Aojia , Li Ruitian , Luo Xuan , Sun Hao
Published: September 2024

We study the production of hyperon resonances in the π+p→pa0+ϕ reaction within an effective Lagrangian approach. The model includes the production of Δ(1940) and Δ(1920) in the intermediate state excited by the ρ and

p

exchanges between the initial proton and π meson. Because of the large contribution of ρ exchange in Δ(1940) production, Δ(1940) is found to be a significant contribution near the threshold in this reaction. We provide total and differential cross section predictions for the reaction and discuss the possible influence of model parameters, off-shell effects, and branching ratios for Δ(1940)→pa0 and Δ(1920)→pa0 decays, which will be useful in future experimental studies. This reaction can provide a platform for studying the features of Δ(1940) resonance, especially the coupling to the pa0 channel.

Published by the American Physical Society
2024
Numerical indication that center vortices drive dynamical mass generation in QCD
Authors: Kamleh Waseem , Leinweber Derek B. , Virgili Adam
Published: September 2024

The first calculation of the response of the momentum space quark propagator to center vortices in the ground state fields of QCD is presented. Center vortices are identified on 2+1-flavor dynamical gauge fields with mπ≃156  MeV to obtain the vortex-removed and vortex-only quark propagator. Dynamical mass generation is found to vanish upon vortex removal, while the vortex-only field is able to generate dynamical mass. These new signatures strengthen the lattice QCD evidence indicating that center vortices underpin both dynamical chiral symmetry breaking and quark confinement.

Published by the American Physical Society
2024
Strong dipole-dipole interactions via enhanced light-matter coupling in composite nanofiber waveguides
Authors: Jain Kritika , Ruks Lewis , le Kien Fam , Busch Thomas
Published: September 2024

We study the interaction of emitters with a composite waveguide formed from two parallel optical nanofibers in regimes of experimental importance for atomic gases or solid-state emitters. Using the exact dyadic Green's function we comprehensively investigate the coupling efficiency and the fiber-induced Lamb shift accounting for variations in emitter positions and fiber configurations. This reveals coupling efficiencies and Purcell factors that are enhanced considerably beyond those using a single fiber waveguide, and robustness in the figures of merit. We finally investigate resonant dipole-dipole interactions and the generation of entanglement between two emitters mediated through the composite waveguide under excitation. We show that the concurrence can be enhanced for two fiber systems, such that entanglement may be present even in cases where it is zero for a single fiber. All-fiber systems are simple in construction and benefit from a wealth of existing telecommunications technologies, while enjoying strong couplings to emitters and offering interesting light-matter functionalities specific to slot waveguides.

Published by the American Physical Society
2024
Comparison of estimation limits for quantum two-parameter estimation
Authors: Yung Simon K. , Conlon Lorcán O. , Zhao Jie , Lam Ping Koy , Assad Syed M.
Published: September 2024

Measurement estimation bounds for local quantum multiparameter estimation, which provide lower bounds on possible measurement uncertainties, have so far been formulated in two ways: by extending the classical Cramér-Rao bound (e.g., the quantum Cramér-Rao bound and the Nagaoka Cramér-Rao bound) and by incorporating the parameter estimation framework with the uncertainty principle, as in the Lu-Wang uncertainty relation. In this work, we present a general framework that allows a direct comparison between these different types of estimation limits. Specifically, we compare the attainability of the Nagaoka Cramér-Rao bound and the Lu-Wang uncertainty relation, using analytical and numerical techniques. We show that these two limits can provide different information about the physically attainable precision. We present an example where both limits provide the same attainable precision and an example where the Lu-Wang uncertainty relation is not attainable even for pure states. We further demonstrate that the unattainability in the latter case arises because the figure of merit underpinning the Lu-Wang uncertainty relation (the difference between the quantum and classical Fisher information matrices) does not necessarily agree with the conventionally used figure of merit (mean-squared error). The results offer insights into the general attainability and applicability of the Lu-Wang uncertainty relation. Furthermore, our proposed framework for comparing bounds of different types may prove useful in other settings.

Published by the American Physical Society
2024
Operando
X-ray and Mass Spectroscopy of Reduced Graphene Oxide (
rGO
)-Mediated Cobalt Catalysts for Boosting the Hydrogen Evolution Reaction
Authors: Mariano Carl Osby M. , Clemente Russell Hizon , Tsai Meng-Hsuan , Chin Yi-Ying , Chen Jin-Ming , Lee Jyh-Fu , Lu Ying-Jui , Chen Chien-Ming , Chen Po-Tuan , Chuang Cheng-Hao
Published: September 2024

Inserting underlying reduced graphene oxide (rGO) into Co aims to regulate the chemical integrity and catalytic ability of the Co upper layer for hydrogen evolution reaction (HER) as a green-hydrogen goal. Principally, an mass spectrometer indicates 3.8 times more considerable hydrogen generation in Co/rGO than in Co. The spectroscopical approaches, combining soft and hard X-ray probing, illustrate the chemical oxidation evolution of electronic

Co

-3 and Co-4 states differently regarding the underlying rGO contribution. A unique examination is regarded as the phase transition from the initial middle to high oxidation and to deoxidation, related to the intermediate Co0 existence and H2 generation. The chemical adsorption of Co–O(H), Co–Hads, and H2 molecules desorption have been assigned their spectral significances. The rGO mediation indicates two significant metal Co and Co–O(H) blocks in the two-dimensional - domain. Density-functional-theory (DFT) calculation provides the regeneration, sustained stability, and decreasing energy barrier of Co–Hads catalysts due to the rGO incorporation, thereby augmenting the HER enhancement through the alternative Volmer-Heyrovsky process. The experiment, including mass spectrometer, soft, and hard X-ray, provides evidence regarding the catalyst’s HER enhancement. This study offers insights into the chemical composition, electronic structure, and active role of Co bonded with or without the extinct OH and H bonds, advancing our comprehension of electrocatalytic reactions, thus taking our knowledge of composite materials to stepwise electrocatalytic reactions forward. This cutting-edge experiment under environment and DFT studies gives critical information regarding the catalytic mechanism and chemical stability of the Co and rGO materials.

Published by the American Physical Society
2024
Greening the procurement: a SMART evaluation of environmental sustainability in Australian government purchasing policies
Authors: Shahin Aryana , Polonsky Michael , Wood Lincoln C. , Presbitero Alfred , Wijayasundara Mayuri
Published: September 2024

Purpose

This study evaluates how well Victorian local councils’ procurement policies align with the sustainable and circular economy (CE) approach that prioritises sustainable and regenerative practices. It proposes a set of criteria designed to effectively integrate environmental sustainability issues into purchasing policies.

Design/methodology/approach

Employing the Specific, Measurable, Assignable, Realistic and Time-bound (SMART) framework, a multi-dimensional content analysis guided by the goal-setting theory was applied to evaluate all 79 Victorian local councils’ procurement policies. This approach provided an assessment of policy specificity, measurability, assignability, realism and time sensitivity in promoting environmental sustainability through purchasing policies.

Findings

The findings underscored a significant deficiency in policy adherence to all SMART criteria concerning environmental sustainability, hindering the effective green purchasing decisions within government entities. This lack of integration of greening in purchasing policy poses challenges for manufacturers of waste-derived goods, obscuring the procurement objectives of these critical public sector customers.

Practical implications

The paper contributes to the sustainable procurement (SP) discourse by proposing guidelines aimed at improving the efficacy of governmental purchasing of sustainable products. These guidelines address the broader imperative to mitigate the environmental impacts of governmental spending on less sustainable goods, thereby fostering ecological sustainability and promoting responsible consumption.

Originality/value

While past studies have often relied on subjective content analysis methods, the SMART assessment used to develop the environmental sustainability criteria for purchasing policies, which distinguishes this study from previous governmental policy evaluation studies. This approach marks a departure from traditional governmental policy evaluation studies, offering a more structured analysis of policy effectiveness in promoting SP practices.
Entrepreneurial orientation and supply chain performance: the roles of entrepreneurial competence and local community networking (evidence from Ghana)
Authors: Agbemude Samuel , Nuertey Dorcas , Poku Emmanuel , Owusu Felix
Published: September 2024

Purpose

This study aims to assess the effect of entrepreneurial orientation on supply chain performance both directly and indirectly through entrepreneurial competence, as well as the moderating role of local community networking in these relationships, within the context of institutional voids in Ghana.

Design/methodology/approach

The study utilized a cross-sectional survey data from 225 small and medium sized enterprises (SMEs) in order to test the hypotheses. The data analysis was conducted using partial least squares structural equation modelling techniques.

Findings

The results revealed that entrepreneurial orientation is a significant positive predictor of both entrepreneurial competence and supply chain performance. Similarly, entrepreneurial competence was shown to positively predict supply chain performance, both directly and as a mediator between entrepreneurial orientation and supply chain performance. Local community networking, however, positively moderated the relationship between entrepreneurial orientation and entrepreneurial competence but not the relationship between entrepreneurial orientation and supply chain performance.

Originality/value

This study contributes to literature by looking at the relationship between entrepreneurial orientation, entrepreneurial competence, local community networking and supply chain performance within the context of an emerging economy with institutional voids. The study shows the importance of an entrepreneurial mindset in developing the necessary skills, competences and abilities needed to survive in the turbulent business environment.
Affective states and a firm’s performance: the mediating role of dynamic managerial capabilities
Authors: Bogodistov Yevgen , Schmidt Susanne
Published: September 2024

Purpose

Extant research supports the importance of dynamic managerial capabilities in capturing managers’ individual roles in organisations’ adjustments to change. This paper develops a multidimensional scale for measuring dynamic managerial capabilities consisting of sensing, seizing and reconfiguration capacities that mediate between managers’ affective states and their firms’ performance.

Design/methodology/approach

The scale is validated in a survey-based study among 204 managers in companies in the United States of America (USA). We applied a multiple regression model (a triple mediation) using each of DMCs’ three dimensions to test the effects of managers’ affective states on their firms’ performance.

Findings

The multidimensional construct of DMCs adds about 15 % of variance explained to a firm’s performance, as perceived by its managers. So managers’ affective states do have an impact on DMCs and, later, on their firms’ performance.

Research limitations/implications

We show the impact of negative and positive affect on DMCs. We also show that DMCs’ three dimensions should be treated in a formative manner that advances discussion on DMCs and their role in a firm’s performance.

Practical implications

Understanding managers’ affective states helps incorporate “hot cognition” into firms’ strategising processes. Although both positive and negative emotions can be helpful, depending on the situation, positive affect is generally more valuable than negative affect as it relates to a firm’s performance.

Originality/value

Our work proposes measuring DMCs based on Teece’s (2007) disaggregation of DMCs into sensing, seizing and reconfiguration capacities. We approach each of these dimensions separately and show that managers’ affective states influence each dimension differently.
Punishment and survival – incarcerated persons' experiences with extreme heat in Texas prisons
Authors: Purdum Carlee , Dixon Benika , Dominick Amite
Published: September 2024

Purpose

The impact of extreme heat on prisons and carceral facilities is becoming increasingly visible, yet remains overlooked by scholars, practitioners and policymakers. Prisons are a unique type of infrastructure designed to severely limit and control the movement of hundreds and even thousands of individuals as a form of punishment. This leads to many significant challenges to mitigating the risk of heat-related illness in prisons and other carceral spaces that have remained overlooked across many disciplines including emergency management, disasters, corrections and public health.

Design/methodology/approach

For this study, we analyzed 192 surveys from incarcerated persons in state prisons throughout Texas to understand how incarceration and the punitive prison environment create challenges to managing extreme heat in prisons.

Findings

We found that characteristics of modern incarceration, including communal distribution of resources, crowded conditions and a lack of agency for incarcerated people, create barriers to accessing resources during periods of extreme heat. Furthermore, the punitive nature of the prison environment as manifested in the relationship between staff and incarcerated persons and certain prison policies also create barriers to incarcerated persons accessing resources to reduce their risk of heat-related illness and death.

Social implications

These issues are particularly relevant to the health and safety of incarcerated persons during periods of extreme temperatures but also speak broadly to the implications of incarceration, disaster risk, and the advancement of human rights for incarcerated people.

Originality/value

This article addresses a gap in the literature by including the perspectives of persons incarcerated in Texas prisons experiencing extreme heat and implicates the characteristics of incarceration and punishment in the production of disaster risk.
Fast food investment in Barbados: the experience of McDonald’s
Authors: Young Marshall Ayanna Omodara , Walkes Alfred
Published: September 2024

Learning outcomes

Specific teaching and learning objectives include to identify factors influencing market expansion decisions and recommend appropriate entry modes, understand factors in the international business environment that contribute to success or failure of international businesses in developing countries, evaluate strategies enabling international businesses to sustain market presence in developing countries and overcome local competition, analyze the concept of local responsiveness in international business operations and suggest strategies for internationalizing domestic companies from developing countries.

Case overview/synopsis

The McDonald’s case examines the challenges associated with market expansion by global brands. The case occurs during the early-globalization era in the 1990s. Barbados, a developing country, is the site for potential expansion. Prospective investors, the Winters, are desirous of establishing a McDonald’s in Barbados. They need to thoroughly analyze the previous experience of McDonald’s against the host country’s current international business environment, e.g. political, economic, cultural and competitive environment. This case analysis provides a framework for understanding the multifaceted reasons behind McDonald’s exit from Barbados, considering the complex interplay of political, economic, sociocultural, technological and legal factors in the international business environment. The case equips the instructor and students to explore the risks of international expansion, particularly in developing country markets. The case study on McDonald’s failure in Barbados highlights the need to thoroughly examine one’s market entry strategy and available information on the host market and be more locally responsive regarding tastes and preferences. The case study also presents essential lessons for firms and planners from developing countries. Local firms innovated and enhanced their operations in response to the threat from the entry of the global fast-food giant. Yet, they did not seek to internationalize once McDonald’s exited the Barbadian market. The case study, therefore, considers strategies firms from developing countries could utilize to penetrate markets from developed countries.

Complexity academic level

At the undergraduate level, the McDonald’s Barbados case can be used in international business classes to highlight risks in the international business environment and the need for a carefully planned and executed market entry strategy.

Supplementary materials

Teaching notes are available for educators only.

Subject code

CSS5: International Business.
Talent management practices and the influence of their use on employee outcomes via perceived career growth
Authors: Aljbour Amro , Ali Muhammad , French Erica
Published: September 2024

Purpose

Talent management can provide an organization with a competitive advantage. However, little is known about how human resource practices pertaining to talent management drive positive outcomes. Drawing on social exchange theory, this study investigates the effect of talent management practices usage on employee commitment and intention to leave. Integrating social exchange theory and the theory of met expectations facilitated predicting the mediating role of perceived career growth in the talent management practices usage-employee outcomes relationship.

Design/methodology/approach

Data were collected using a survey from 268 employees from eight organizations from the financial and services industries in Jordan.

Findings

Talent management practices usage has a significant direct positive effect on employee commitment but no direct effect on employees’ intention to leave. Further, there is pioneering evidence that perceived career growth mediates the following relationships: talent management practices usage and commitment and talent management practices usage and intention to leave.

Originality/value

The study provides unprecedented evidence of the effect of TM practices usage on employee outcomes and the role of perceived career growth in the TM practices usage-employee outcomes relationship from an underexplored context of Jordon. Our research results contribute to theory development in TM by supporting, extending and integrating social exchange theory and the theory of met expectations.
Intersectional analysis of the labour market impacts of COVID on women with young children and in low-skilled jobs
Authors: Fang Tony , Gunderson Morley , Ha Viet , Ming Hui
Published: September 2024

Purpose

This paper analyzes the differential experiences of women in the Canadian labour market who hold lower-skilled jobs and have school-age children during two waves of Covid compared with more typical conditions pre-pandemic. The article seeks to test the hypothesis that workers at the intersection of womanhood, motherhood and precarious employment would endure even more disadvantageous labour market outcomes during the Covid pandemic than they did prior to it.

Design/methodology/approach

We employ a Gender-Based Plus (GBA+) and intersectionality lens to examine the differential effect of Covid on the effect of the trifecta of being a woman in a lower-skilled job and facing a motherhood penalty from school-age children. We use a Difference-in-Difference framework with Canadian Labour Force Survey (LFS) data to examine the differential effect of two waves of Covid on three labour market outcomes: employment, hours worked and hourly wages.

Findings

We find that being a woman in a lower-skilled job with school-age children is associated with lower employment, hours worked and wages in normal times compared to males in those same situations. Such women also face the most severe adjustment consequence from the Covid shock, with that adjustment concentrated on the margin of employment and restricted to the First Wave and not the subsequent Omicron Wave.

Originality/value

The paper studies a specific intersectional group, assesses pre-pandemic, peak-pandemic and late-pandemic differences in labour market outcomes and runs separate estimations for different job skill levels. We also study a more comprehensive list of labour market outcomes than most studies of a similar nature.