bluuebunny/crossref_metadata_2025 huggingface dataset:
Supramodal neural information supports stimulus-driven attention across cortical levels
Authors: Niedernhuber Maria , Fardo Francesca , Allen Micah , Bekinschtein Tristan
Published: February 2024

Sensory systems utilise stimulus-driven attention to survey the environment for significant features. The question arises: are the cortical networks that influence stimulus-driven attention supramodal or specific to each sensory modality? Here we employed a hierarchical target detection task (n=30), examining cortical responses linked to the detection of salient targets in the somatosensory and auditory modality. In a temporal decoding analysis, we reveal a transient early supramodal process activated by target detection. We also demonstrate that both common and unique modulations of salience-related cortical responses to somatosensory and auditory targets involve modality-specific and frontal regions using Parametric Empirical Bayes. Specifically, we found that the inferior frontal gyri share information across both sensory modalities, while recurrent information transfer between ipsilateral inferior frontal gyri and associative regions was modality-specific. Finally, we showed both supramodal and modality-specific attentional modulations of effective connectivity linking regions across hierarchical levels in the cortex. Our results provide evidence for an attention network which integrates information across inferior frontal cortices to detect salient targets irrespective of their specific sensory modality. Beyond the notion of a supramodal attention system, our findings support the role of modality-specific cortices in processing inputs from other sensory modalities, highlighting that attention can bias these processes at multiple stages of the cortical hierarchy.

Author summary

A key task of the brain is to deploy attention to detect important sensory events in its environment. How does the brain coordinate information from different senses when a sensory event pops out from the environment? Here we designed a nested oddball paradigm in which expectations about somatosensory and auditory stimuli are violated while high-density EEG is recorded. We also varied the extent to which the odd stimulus pops out from its sensory environment. Using temporal decoding, we reveal a supramodal short-lived cortical process when salient targets are detected. In an effective connectivity analysis, we also show that the detection of salient targets relies on a common interhemispheric inhibition between inferior frontal gyri. Beyond that, there are supramodal and modality-specific changes in effective connectivity linking associative and modality-specific regions in the cortex. Our results support a rapid and short-lived supramodal process in a distributed saliency detection system extending across the cortical hierarchy.
Intercalated amygdala dysfunction drives extinction deficits in theSapap3mouse model of obsessive-compulsive disorder
Authors: St. Laurent Robyn , Kusche Kelly M , Kreitzer Anatol C , Malenka Robert C
Published: February 2024

Background

The avoidance of aversive stimuli due to negative reinforcement learning is critical for survival in real-world environments, which demand dynamic responding to both positive and negative stimuli that often conflict with each other. Individuals with obsessive-compulsive disorder (OCD) commonly exhibit impaired negative reinforcement and extinction, perhaps involving deficits in amygdala functioning. An amygdala subregion of particular interest is the intercalated nuclei of the amygdala (ITC) which has been linked to negative reinforcement and extinction, with distinct clusters mediating separate aspects of behavior. This study focuses on the dorsal ITC cluster (ITCd) and its role in negative reinforcement during a complex behavior that models real-world dynamic decision making.

Methods

We investigated the impact of ITCdfunction on negative reinforcement and extinction by applying fiber photometry measurement of GCamp6f signals and optogenetic manipulations during a platform-mediated avoidance task in a mouse model of OCD-like behavior: theSapap3-null mouse.

Results

We find impaired neural activity in the ITCdof male and femaleSapap3-null mice to the encoding of negative stimuli during platform-mediated avoidance.Sapap3-null mice also exhibit deficits in extinction of avoidant behavior, which is modulated by ITCdneural activity.

Conclusions

Sapap3-null mice fail to extinguish avoidant behavior in platform-mediated avoidance, due to heightened ITCdactivity. This deficit can be rescued by optogenetically inhibiting ITCdduring extinction. Together, our results provide insight into the neural mechanisms underpinning negative reinforcement deficits in the context of OCD, emphasizing the necessity of ITCdin responding to negative stimuli in complex environments.
Streptavidin-drug conjugates streamline optimization of antibody-based conditioning for hematopoietic stem cell transplantation
Authors: Yelamali Aditya R. , Chendamarai Ezhilarasi , Ritchey Julie K. , Rettig Michael P. , DiPersio John F. , Persaud Stephen P.
Published: February 2024

Hematopoietic stem cell transplantation (HSCT) conditioning using antibody-drug conjugates (ADC) is a promising alternative to conventional chemotherapy- and irradiation-based conditioning regimens. The drug payload bound to an ADC is a key contributor to its efficacy and potential toxicities; however, a comparison of HSCT conditioning ADCs produced with different toxic payloads has not been performed. Indeed, ADC optimization studies in general are hampered by the inability to produce and screen multiple combinations of antibody and drug payload in a rapid, cost-effective manner. Herein, we used Click chemistry to covalently conjugate four different small molecule payloads to streptavidin; these streptavidin-drug conjugates can then be joined to any biotinylated antibody to produce stable, indirectly conjugated ADCs. Evaluating CD45-targeted ADCs produced with this system, we found the pyrrolobenzodiazepine (PBD) dimer SGD-1882 was the most effective payload for targeting mouse and human hematopoietic stem cells (HSCs) and acute myeloid leukemia cells. In murine syngeneic HSCT studies, a single dose of CD45-PBD enabled near-complete conversion to donor hematopoiesis. Finally, human CD45-PBD provided significant antitumor benefit in a patient-derived xenograft model of acute myeloid leukemia. As our streptavidin-drug conjugates were generated in-house with readily accessible equipment, reagents, and routine molecular biology techniques, we anticipate this flexible platform will facilitate the evaluation and optimization of ADCs for myriad targeting applications.
Functional architecture of intracellular oscillations in hippocampal dendrites
Authors: Liao Zhenrui , Gonzalez Kevin C. , Li Deborah M. , Yang Catalina M. , Holder Donald , McClain Natalie E. , Zhang Guofeng , Evans Stephen W. , Chavarha Mariya , Yi Jane , Makinson Christopher D. , Lin Michael Z. , Losonczy Attila , Negrean Adrian
Published: February 2024

Fast electrical signaling in dendrites is central to neural computations that support adaptive behaviors. Conventional techniques lack temporal and spatial resolution and the ability to track underlying membrane potential dynamics present across the complex three-dimensional dendritic arborin vivo. Here, we perform fast two-photon imaging of dendritic and somatic membrane potential dynamics in single pyramidal cells in the CA1 region of the mouse hippocampus during awake behavior. We study the dynamics of subthreshold membrane potential and suprathreshold dendritic events throughout the dendritic arborin vivoby combining voltage imaging with simultaneous local field potential recording,post hocmorphological reconstruction, and a spatial navigation task. We systematically quantify the modulation of local event rates by locomotion in distinct dendritic regions and report an advancing gradient of dendritic theta phase along the basal-tuft axis, then describe a pre-dominant hyperpolarization of the dendritic arbor during sharp-wave ripples. Finally, we find spatial tuning of dendritic representations dynamically reorganizes following place field formation. Our data reveal how the organization of electrical signaling in dendrites maps onto the anatomy of the dendritic tree across behavior, oscillatory network, and functional cell states.
The metabolically protective energy expenditure increase ofPik3r1-related insulin resistance is not explained by Ucp1-mediated thermogenesis
Authors: Luijten Ineke , Onishi Ami , McKay Eleanor J. , Bengtsson Tore , Semple Robert K.
Published: February 2024

Human SHORT syndrome is caused by dominant negative humanPIK3R1mutations that impair insulin-stimulated phosphoinositide 3-kinase (PI3K) activity. This produces severe insulin resistance (IR) and often reduced adiposity, commonly described as lipodystrophy. However unlike human primary lipodystrophies, SHORT syndrome does not feature fatty liver or dyslipidaemia.Pik3r1Y657*/WT(Pik3r1Y657*) mice metabolically phenocopy humans, moreover exhibiting increased energy expenditure. We have hypothesised that this increased energy expenditure explains protection from lipotoxicity, and suggested that understanding its mechanism may offer novel approaches to mitigating the metabolic syndrome. We thus set out to determine whether increased Ucp1-dependent thermogenesis explains the increased energy expenditure inPik3r1-related IR. Male and female Pik3r1Y657*mice challenged with a 45% fat diet for 3 weeks at 21°C showed reduced metabolic efficiency not explained by changes in food intake or physical activity. No changes were seen in thermoregulation, assessed by thermal imaging and a modified Scholander protocol. Ucp1-dependent thermogenesis, assessed by norepinephrine-induced oxygen consumption, was also unaltered. Housing at 30°C did not alter the metabolic phenotype of male Pik3r1Y657*mice, but led to lowered physical activity in female Pik3r1Y657*mice compared to controls. Nevertheless these mice still exhibited increased energy expenditure. Ucp1-dependent thermogenic capacity at 30°C was similar in Pik3r1Y657*and WT mice. We conclude that the likely metabolically protective ‘energy leak’ in Pik3r1-related IR is not caused by Ucp1-mediated BAT hyperactivation, nor impaired thermal insulation. Further metabolic studies are required to seek alternative explanations such as non Ucp1-mediated futile cycling.

New and Noteworthy

Understanding how Pik3r1Y657*mice and humans are protected from lipotoxicity despite insulin resistance may suggest new ways to mitigate metabolic syndrome. We find reduced metabolic efficiency and increased energy expenditure in Pik3r1Y657*mice but no differences in locomotion, thermoregulation or Ucp1-dependent thermogenesis. Protective energy expenditure in Pik3r1-related insulin resistance has an alternative, likely metabolic, explanation
Chemogenetic activation of microglial Gi signaling decreases microglial surveillance and impairs neuronal synchronization
Authors: Zhao Shunyi , Wang Lingxiao , Liang Yue , Zheng Jiaying , Umpierre Anthony D. , Wu Long-Jun
Published: February 2024

Microglia actively survey the brain and dynamically interact with neurons to maintain brain homeostasis. Microglial Gi-protein coupled receptors (Gi-GPCRs) play a critical role in microglia-neuron communications. However, the impact of temporally activating microglial Gi signaling on microglial dynamics and neuronal activity in the homeostatic brain remains largely unknown. In this study, we employed Gi-based Designer Receptors Exclusively Activated by Designer Drugs (Gi-DREADD) to selectively and temporally modulate microglial Gi signaling pathway. By integrating this chemogenetic approach within vivotwo-photon imaging, we observed that exogenous activation of microglial Gi signaling transiently inhibited microglial process dynamics, reduced neuronal activity, and impaired neuronal synchronization. These altered neuronal functions were associated with a decrease in interactions between microglia and neuron somata. Altogether, this study demonstrates that acute, exogenous activation of microglial Gi signaling can regulate neuronal circuit function, offering a potential pharmacological target for neuromodulation through microglia.
ATP13A1 engages GET3 to facilitate substrate-specific translocation
Authors: Yang Xiaoyan , Li Tingting , Fang Zhiyu , Feng Zhigang , Zou Yan
Published: February 2024

Proper localization of proteins to their final destinations is crucial for preserving cellular structure and functions. The interpretation and sorting of highly variable targeting sequences in secreted and membrane proteins, however, pose a challenge in achieving precise localization within specific secretory apparatus. In this study, we demonstrate that atypical signal sequences characterized by high hydrophobicity and/or the absence of characteristic charges undergo targeting to the endoplasmic reticulum (ER) in a reverse orientation, followed by partial cleavage. The P5A- ATPase ATP13A1 recognizes the cleaved signal sequence and dislocates it to the targeting factor GET3, subsequently engaging SEC61 for further translocation. Our findings unveil a comprehensive translocation pathway that operates in a substrate- specific manner, ensuring both high efficiency and fidelity in the protein subcellular localization.
How to design optimal brain stimulation to modulate phase-amplitude coupling?
Authors: Duchet Benoit , Bogacz Rafal
Published: February 2024

Objective

Phase-amplitude coupling (PAC), the coupling of the amplitude of a faster brain rhythm to the phase of a slower brain rhythm, plays a significant role in brain activity and has been implicated in various neurological disorders. For example, in Parkinson’s disease, PAC between the beta (13–30 Hz) and gamma (50–200 Hz) rhythms in the motor cortex is exaggerated, while in Alzheimer’s disease, PAC between the theta (4-8 Hz) and gamma rhythms is diminished. Modulating PAC (i.e. reducing or enhancing PAC) using brain stimulation could therefore open new therapeutic avenues. However, while it has been previously reported that phase-locked stimulation can increase PAC, it is unclear what the optimal stimulation strategy to modulate PAC might be. Here, we provide a theoretical framework to narrow down the experimental optimisation of stimulation aimed at modulating PAC, which would otherwise rely on trial and error.

Approach

We make analytical predictions using a Stuart-Landau model, and confirm these predictions in a more realistic model of coupled neural populations.

Main results

Our framework specifies the critical Fourier coefficients of the stimulation waveform which should be tuned to optimally modulate PAC. Depending on the characteristics of the amplitude response curve of the fast population, these components may include the slow frequency, the fast frequency, combinations of these, as well as their harmonics. We also show that the optimal balance of energy between these Fourier components depends on the relative strength of the endogenous slow and fast rhythms, and that the alignment of fast components with the fast rhythm should change throughout the slow cycle. Furthermore, we identify the conditions requiring to phase-lock stimulation to the fast and/or slow rhythms.

Significance

Together, our theoretical framework lays the foundation for guiding the development of innovative and more effective brain stimulation aimed at modulating PAC for therapeutic benefit.
Novel murine closed-loop auditory stimulation paradigm elicits macrostructural sleep benefits in neurodegeneration
Authors: Dias Inês , Kollarik Sedef , Siegel Michelle , Baumann Christian R. , Moreira Carlos G. , Noain Daniela
Published: February 2024

Boosting slow-wave activity (SWA) by modulating slow-waves through closed-loop auditory stimulation (CLAS) might provide a powerful nonpharmacological tool to investigate the link between sleep and neurodegeneration. Nevertheless, CLAS in this context was not yet explored. Here, we established mouse CLAS (mCLAS)-mediated SWA enhancement and explored its effects onto sleep deficits in neurodegeneration, by targeting the up-phase of slow-waves in mouse models of Alzheimer’s (AD, Tg2576) and Parkinson’s disease (PD, M83). We found that tracking a 2Hz component of slow-waves leads to highest precision of NREM sleep detection in mice, and that its combination with a 30° up-phase-target produces a significant SWA 15-30% increase from baseline in WTADand TGADmice versus a MOCK group. Conversely, combining 2Hz with a 40° phase target yields a significant increase ranging 30-35% in WTPDand TGPDmice. Interestingly, these phase-target-triggered SWA increases are not genotype dependent but strain specific. Sleep alterations that may contribute to disease progression and burden were described in AD and PD lines. Notably, pathological sleep traits where rescued by mCLAS, which elicited a 14% decrease of pathologically heightened NREM sleep fragmentation in TGADmice, accompanied by a steep decrease in microarousal events during both light and dark periods. Overall, our results indicate that model-tailored phase-targeting is key to modulate SWA through mCLAS, prompting the acute alleviation of key neurodegeneration-associated sleep phenotypes and potentiating sleep regulation and consolidation. Further experiments assessing the long-term effect of mCLAS in neurodegeneration may majorly impact the establishment of sleep-based therapies.
Influence of insulin sensitivity on food cue evoked functional brain connectivity in children
Authors: Semeia Lorenzo , Veit Ralf , Zhao Sixiu , Luo Shan , Angelo Brendan , Birkenfeld Andreas L. , Preissl Hubert , Xiang Anny H. , Kullmann Stephanie , Page Kathleen A.
Published: February 2024

Objective

Insulin resistance during childhood is a risk factor for developing type 2 diabetes and other health problems later in life. Studies in adults have shown that insulin resistance affects regional and network activity in the brain which are vital for behavior, e.g. ingestion and metabolic control. To date, no study has investigated whether brain responses to food cues in children are associated with peripheral insulin sensitivity.

Methods

We included 53 children (36 girls) between the age of 7-11 years, who underwent an oral Glucose Tolerance Test (oGTT) to estimate peripheral insulin sensitivity (ISI). Brain responses were measured using functional magnetic resonance imaging (fMRI) before and after glucose ingestion. We compared food-cue task-based activity and functional connectivity (FC) between children with low and high ISI, adjusted for age and BMIz.

Results

Independent of prandial state (i.e., glucose ingestion), children with lower ISI showed higher FC between the anterior insula and caudate and lower FC between the posterior insula and mid temporal cortex than children with higher ISI. Sex differences were found based on prandial state and peripheral insulin sensitivity in the insular FC. No differences were found on whole-brain food-cue reactivity.

Conclusions

Children with low peripheral insulin sensitivity showed differences in food cue evoked response particularly in insula functional connectivity. These differences might influence eating behavior and future risk of developing diabetes.
Enhancement of Temporal Processing via Transcutaneous Vagus Nerve Stimulation
Authors: Bahadori Mehrdad , Bhutani Neha , Bella Simone Dalla
Published: February 2024

Background

The vagus nerve, a crucial component of the parasympathetic nervous system, serves as a vital communication link between the brain and body. Recent studies indicate that auricular stimulation of the vagus nerve can influence executive functions by increasing activity in brain regions like the prefrontal cortex. While prefrontal areas are associated with temporal processing, it remains unclear whether vagus nerve stimulation can also impact time perception.

Hypothesis

The stimulation of the vagus nerve via its auricular branch may enhance performance in temporal processing by boosting activities in prefrontal brain areas related to temporal processing.

Methods

Temporal processing abilities were assessed using an anisochrony detection task, where participants identified temporal irregularities in otherwise isochronous sequences while undergoing transcutaneous Vagus Nerve Stimulation (tVNS) or sham stimulation.

Results

The results of this study, for the first time, revealed that participants could recognize smaller temporal shifts when the vagus nerve was stimulated, compared to the sham condition.

Conclusion

The findings suggest that vagus nerve stimulation modulates temporal processing, supporting the notion that transcutaneous stimulation of the vagus nerve can influence cognitive functions related to temporal processing, possibly by enhancing prefrontal activities.
Understanding magnetoelectric switching in
BiFeO3
thin films
Authors: Fedorova Natalya S. , Nikonov Dmitri E. , Mangeri John M. , Li Hai , Young Ian A. , Íñiguez Jorge
Published: February 2024

In this work we use a phenomenological theory of ferroelectric switching in BiFeO3 thin films to uncover the mechanism of the two-step process that leads to the reversal of the weak magnetization of these materials. First, we introduce a realistic model of a BiFeO3 film, including the Landau energy of isolated domains as well as the constraints that account for the presence of the substrate and the multidomain configuration found experimentally. We use this model to obtain statistical information about the switching behavior—by running dynamical simulations based on the Landau-Khalatnikov time-evolution equation, including thermal fluctuations—and we thus identify the factors that drive the two-step polarization reversal observed in the experiments. Additionally, we apply our model to test potential strategies for optimizing the switching characteristics.

Published by the American Physical Society
2024
Indications of electron emission from the deuteron-deuteron threshold resonance
Authors: Czerski K. , Dubey R. , Kaczmarski M. , Kowalska A. , Targosz-Ślęczka N. , Das Haridas G. , Valat M.
Published: February 2024

Electron emission in the deuteron-deuteron reaction supporting existence of the single-particle threshold resonance in He4 has been observed for the first time. The measured electron energy spectrum and the electron-proton branching ratio agree very well with the assumed electron-positron pair creation decay of the 0+ resonance state to the ground state and the detailed Monte Carlo simulations of the experimental energy spectrum.

Published by the American Physical Society
2024
Isosinglet vectorlike leptons at
e+e−
colliders
Authors: Bhattiprolu Prudhvi N. , Martin Stephen P. , Pierce Aaron
Published: February 2024

We study weak isosinglet vectorlike leptons that decay through a small mixing with the tau lepton, for which the discovery and exclusion reaches of the Large Hadron Collider and future proposed hadron colliders are limited. We show how an e+e− collider may act as a discovery machine for these τ′ particles, demonstrate that the τ′ mass peak can be reconstructed in a variety of distinct signal regions, and explain how the τ′ branching ratios may be measured.

Published by the American Physical Society
2024
Global analysis and LHC study of a vectorlike extension of the standard model with extra scalars
Authors: Hernández A. E. Cárcamo , Kowalska Kamila , Lee Huchan , Rizzo Daniele
Published: February 2024

We perform a global analysis of a vectorlike extension of the Standard Model, which also features additional doublet and singlet scalars. The usual Yukawa interactions are forbidden in this setup by an extra U(1) global symmetry and the masses of the second and third family quarks and leptons are generated via the mixing with the vectorlike sector. We identify three best-fit benchmark scenarios which satisfy the constraints imposed by the stability of the scalar potential, the perturbativity of the coupling constants, the measurement of the muon anomalous magnetic moment and the nonobservation of the flavor violating tau decays. We show that dominant contributions to the muon (g−2) originate in this model from the charged Higgs/neutral lepton one-loop diagrams, thus correcting an inaccurate statement than can be found in the literature. We also perform a detailed LHC analysis of the benchmark scenarios. We investigate the experimental constraints stemming from direct searches for vectorlike quarks, vectorlike leptons, and exotic scalars. While we show that the model is not currently tested by any collider experiment, we point out that decays of a heavy Higgs boson into two tau leptons may offer a smoking gun signature for the model verification in upcoming runs at the LHC.

Published by the American Physical Society
2024
Decay property of the
X(3842)
as the
ψ3(1D33)
state
Authors: Li Wei , Pei Su-Yan , Wang Tianhong , Feng Tai-Fu , Wang Guo-Li
Published: February 2024

In this paper, the new particle X(3842) discovered by the LHCb Collaboration is identified to be the ψ3(13D3) state. We study its strong decays with the combination of the Bethe-Salpeter method and the P30 model. Its electromagnetic (EM) decay is also calculated by the Bethe-Salpeter method within the Mandelstam formalism. The strong decay widths are Γ[X(3842)→D0D¯0]=1.27 MeV and Γ[X(3823)→D+D−]=1.08  MeV, and the ratio is B[X(3842)→D+D−]/B[X(3823)→D0D¯0]=0.84. The EM decay width is Γ[X(3842)→χc2γ]=0.29  MeV. We also estimate the total width to be 2.87 MeV, which is in good agreement with the experimental data 2.79−0.86+0.86  MeV. Since the used relativistic wave functions include different partial waves, we also study the contributions of different partial waves in electromagnetic decay.

Published by the American Physical Society
2024
Studying the mass sensitivity of air-shower observables using simulated cosmic rays
Authors: Flaggs Benjamin , Coleman Alan , Schröder Frank G.
Published: February 2024

Using simulations, we investigate the mass sensitivity of cosmic-ray air-shower observables for sites at the South Pole and Malargüe, Argentina, the respective locations of the IceCube Neutrino Observatory and the Pierre Auger Observatory. Exact knowledge of observables from air-shower simulations was used to study the event-by-event mass separation between proton, helium, oxygen, and iron primary cosmic rays with a Fisher linear discriminant analysis. Dependencies on the observation site as well as the energy and zenith angle of the primary particle were studied in the ranges from 1016.0–1018.5  eV and 0° to 60°; they are mostly weak and do not change the qualitative results. Promising proton-iron mass separation is achieved using combined knowledge of all studied observables, also when typical reconstruction uncertainties are accounted for. However, even with exact measurements, event-by-event separation of intermediate-mass nuclei is challenging and better methods than the Fisher discriminant and/or the inclusion of additional observables will be needed. As an individual observable, high-energy muons (>500  GeV) provide the best event-by-event mass discrimination, but the combination of muons of any energy and Xmax provides already a high event-by-event separation between proton-iron primaries at both sites. We also confirm that the asymmetry and width parameters of the air-shower longitudinal profile, R and L, are mass sensitive. Only R seems to be suitable for event-by-event mass separation, but L can potentially be used to statistically determine the proton-helium ratio. Overall, our results motivate the coincident measurement of several air-shower observables, including at least Xmax and the sizes of the muonic and electromagnetic shower components, for the next generation of air-shower experiments.

Published by the American Physical Society
2024
Exploring student reasoning in statistical mechanics: Identifying challenges in problem-solving groups
Authors: Koerfer Ebba , Gregorcic Bor
Published: February 2024

Statistical mechanics has received limited attention in physics education research and remains a relatively underrepresented topic even in research on upper-division physics courses. The purpose of this study was to explore potential challenges that physics students encounter when they solve statistical mechanics problems in groups. Adopting a grounded approach, we video recorded and analyzed nine small student groups engaging in collaborative problem solving on the topic. The analysis involved iterative thematic coding, which gave rise to ten emergent categories of challenges. These were later divided into two broad groupings: and . In the first grouping, we list seven identified categories related to the concepts of macrostates and microstates, distinguishable and indistinguishable particles, temperature, entropy, energy, equilibrium, heat bath, the Boltzmann distribution, and the partition function. In the second grouping, we list three categories related to the inappropriate application of common relations, difficulty managing tensions between calculated results and qualitative reasoning, and coming up with definitions of new and inconsistent concepts. Some of our findings are supported by existing research on the topic, and others are previously unreported. Based on our findings, we propose that future research should investigate the relations between the identified challenges on one hand, and students’ epistemological framing, reasoning, and use of multiple representations on the other. Finally, we suggest that teachers should spend time engaging students in a conceptual discussion of the central ideas of statistical mechanics, motivating the choice and pointing out limitations of commonly used toy models, and linking course content to real-world phenomena.

Published by the American Physical Society
2024
Convolutional neural network approach for the automated identification of in cellulo crystals
Authors: Kardoost Amirhossein , Schönherr Robert , Deiter Carsten , Redecke Lars , Lorenzen Kristina , Schulz Joachim , de Diego Iñaki
Published: February 2024

In cellulo crystallization is a rare event in nature. Recent advances that have made use of heterologous overexpression can promote the intracellular formation of protein crystals, but new tools are required to detect and characterize these targets in the complex cell environment. The present work makes use of Mask R-CNN, a convolutional neural network (CNN)-based instance segmentation method, for the identification of either single or multi-shaped crystals growing in living insect cells, using conventional bright field images. The algorithm can be rapidly adapted to recognize different targets, with the aim of extracting relevant information to support a semi-automated screening pipeline, in order to aid the development of the intracellular protein crystallization approach.
Electrochemical migration behavior between Cu and Ag under a thin electrolyte layer containing chloride
Authors: Luo Lu , Qi Kang , Huang Hualiang
Published: February 2024

Purpose

The purpose of this paper is to investigate the effects of chloride ion concentration and applied bias voltage on the electrochemical migration (ECM) behavior between Cu and Ag under an NaCl thin electrolyte layer (TEL).

Design/methodology/approach

A self-made experimental setup for the ECM behavior between Cu and Ag was designed. An HD video measurement microscopy was used to observe the typical dendrite/corrosion morphology and pH distribution. Short-circuit time (SCT), short-circuit current density and the influence of the galvanic effect between Cu and Ag on their ECM behavior were studied by electrochemical tests. The surface morphology and composition of dendrite were characterized by FESEM/EDS.

Findings

The SCT increased with increasing NaCl concentration but decreased with increasing applied bias voltage, and the SCT between Cu and Ag was less than that between Cu and Cu because their galvanic effect accelerated the dissolution and migration of Cu. When NaCl concentration was less than or equal to 6 mmol/L, cedar-like dendrite was formed, whereas no dendrite formed and only precipitation occurred at high chloride ion concentration (100 mmol/L). The composition of the dendrite between Cu and Ag was copper.

Research limitations/implications

The significance of this study is to clarify the ECM failure mechanism of printed circuit board (PCB) with an immersion silver surface finish (PCB-ImAg).

Practical implications

This study provides a basic theoretical basis for the selection of protective measures and metal coatings for PCB.

Social implications

The social implication of this study is to predict the service life of PCB.

Originality/value

The ECM behavior of dissimilar metals under a TEL was investigated, the influence of the galvanic effect between them on their ECM was discussed, and the SCT increased with increasing NaCl concentration.
Career enhancement strategies, supportive work relationships and subjective career success: the moderating role of family–work conflict
Authors: Rawat Anushri , Nadavulakere Shiva , Isenhour Linda , McEnery Jean
Published: February 2024

Purpose

Our study examines the impact of career enhancing strategies (CES), supportive work relationships and family–work conflict (FWC) on subjective career success.

Design/methodology/approach

The data were sourced from 107 professionals, who were the members of an alumni LinkedIn group of the Masters Human Resource degree program from a university in the Midwestern United States. Multiple regression analysis was employed to test the study hypotheses.

Findings

Results indicate that both forms of CES – networking and mentoring – were positively associated with subjective career success, and there exists a positive association between perceived organizational support and subjective career success. Further, FWC moderates the relationship between subjective career success and mentoring and also moderates the relationship between subjective career success and perceived supervisor support.

Practical implications

Organizations should provide opportunities to employees for networking and institute formal mentoring programs to enhance employees' perceptions of subjective career success. It is also crucial for organizations to promote work–life balance initiatives that can help reduce the levels of FWC experienced by employees.

Originality/value

Our study makes important contributions to the extant literature by highlighting the importance of CES and supportive work relationships in ensuring subjective career success. It also identifies an important moderator, FWC, which can significantly impact subjective career success.
Resources integrators in social media: an analysis of value cocreation
Authors: Losada-Otalora Mauricio , Peña-García Nathalie , Juliao-Rossi Jorge
Published: February 2024

Purpose

This study aims to identify the groups of value cocreators in the context of social media in the retail banking industry and resources that predict customer membership among different groups of value cocreators.

Design/methodology/approach

This study reviewed the literature and developed measurement instruments for the constructs of interest. Data were collected from 406 customers in an emerging market in 2019 and analyzed using latent profile analysis.

Findings

This study identified three profiles of value cocreators on social media based on the actual practices of resource integration that enliven value cocreation. Second, this study explains the differences in the performance of resource integration practices to cocreate by the types of resources that customers integrate into social media. Third, this study fills the need for knowledge of value cocreation in different contexts and industries (e.g. banks).

Originality/value

This study analytically relates a set of resources to the variety and intensity of the value cocreation practices adopted by bank customers in interactive environments. The emphasis on how value cocreation practices in online environments combined with customer resources (e.g., a person-centered approach) allows to identify unique profiles of value cocreators on social media. The findings inform managers of the profiles of cocreators, which customers are more attractive as value cocreators on social media, and which resources managers should help customers develop to increase cocreation on social media.
Labor unrest at Wistron Corporation India plant – What went wrong?
Authors: Saldanha Avil Terrance , Aranha Rekha , Chandran Vijaya
Published: February 2024

Learning outcomes

After completion of this case study, students/managers will be able to analyze reasons for the labor unrest at Wistron Corporation’s Indian manufacturing plant; examine the implementation of labor regulations applicable to the employment of contract workers by Wistron Corporation; infer the problems associated with rapid expansion in the workforce; analyze the labor regulatory challenges faced by Wistron Corporation; and demonstrate problem-solving skills.

Case overview/synopsis

The focus of this case study was the crisis faced by Apple’s contract manufacturer  –  Wistron Corporation due to labor unrest, riots and violence in its production facility located near Bangalore in India. This case study discussed the CEO’s dilemma in resolving the crisis and regaining the confidence of stakeholders, namely, the contract employees, Apple Inc. and the State Government of Karnataka. To give the readers an overview of the crisis – this case discussed in detail the underlying reasons for the labor unrest such as a rapid increase in manpower, unilateral increase in working hours without extra pay, unjustified pay cuts, understaffed and underqualified human resources (HR) department, ill-equipped attendance and payroll system. It also gave an overview of mistakes in labor management that could be avoided by a manufacturing firm. The case also discussed the pressure faced by the Wistron CEO due to probation and a new business freeze by Apple Inc. This case study is suitable for understanding the complexities of labor laws and the legal complications that can arise when a corporation disregards local labor laws while operating in foreign countries.

Complexity academic level

The case is best suited for postgraduate and executive MBA students studying labor law, industrial psychology and HR management in commerce and business management streams. The authors suggest that the instructor should inform students to read the case study before attending the 90-min session. It can be executed in the classroom after discussing the theoretical concepts.

Supplementary materials

Teaching notes are available for educators only.

Subject code

CSS 6: Human Resource Management.
The impact of local entrepreneurial initiatives on women entrepreneur empowerment: the case of cooperative social ventures in Morocco
Authors: Jabbouri Rachid , Truong Yann , Issa Helmi
Published: February 2024

Purpose

We explore how NGO’s local entrepreneurial initiatives to empower women entrepreneurs can compensate for weak state policies for women in a context of male-dominated socio-cultural norms.

Design/methodology/approach

We use the case of a local entrepreneurial initiative launched in the Atlas region of Morocco, the Empowering Women in the Atlas Initiative (EWA). We collected data through 51 semi-structured interviews of women entrepreneurs in three cooperatives which exploit the natural resources of their region to establish a social venture. Our data are longitudinal as they were collected at two time periods: before and after the initiative.

Findings

The findings of this study suggest that local entrepreneurial initiatives can have a significant impact on rural women entrepreneurs’ empowerment. The improved perception of empowerment has not only helped them develop capacities to leverage the business opportunities linked to the natural resources of their region, but it has also increased their status and role within their family and community.

Practical implications

We make recommendations for policymakers to encourage this type of initiative to compensate for the absence of supporting policies geared toward women.

Originality/value

Our study is one of the first to look at empowerment as a policy instrument to develop women entrepreneurial activities in rural areas of developing countries. Our paper uses a unique hierarchical perspective and a multidimensional framework for analyzing social cooperative ventures and rural women entrepreneurs’ empowerment. Our paper unravels interesting insights for women entrepreneurs’ narration strategies.
Impression management through social media: impact on the market performance of musicians’ human brands
Authors: Porto Rafael Barreiros , Borges Carla Peixoto , Dubois Paulo Gasperin
Published: February 2024

Purpose

Human brands in the music industry use self-presentation tactics on social media to manage audience impressions. This practice has led to many posts asking followers to adopt behaviors favoring the human brand. However, its effectiveness in leveraging relevant performance metrics for musicians outside social media, such as popularity in specialized media, music sales and number of contracted concerts, needs further exploration. This study aims to reveal the effect of impression management tactics conveyed on social media on the market performance of musicians’ human brands.

Design/methodology/approach

Secondary data research classifies 5,940 social media posts from 11 music artists into self-presentation tactics (self-promotion, exemplification, supplication and ingratiation). It shows their predictions on three market performance metrics in an annual balanced panel study.

Findings

Impression management tactics via posts on social media are mostly self-promotion, improving the musicians’ market performance by increasing the number of contracted concerts. Conversely, ingratiation generated the most positive effect on the musician’s popularity but reduced music sales. Besides lowering the musicians’ popularity, exemplification also reduced the number of contracted concerts, while the supplication had no significant effect.

Originality/value

To the best of the authors’ knowledge, the research is the first to use social media postings of musicians’ official human brand profiles based on self-presentation typologies as a complete impression management tool. Furthermore, it is the first to test the effects of these posts on market performance metrics (i.e. outside of social media) in a longitudinal study.
Management of cyber risks in the library: analysis of information security awareness of Estonian library employees
Authors: Kont Kate-Riin
Published: February 2024

Purpose

This article surveys why libraries are vulnerable to social engineering attacks and how to manage risks of human-caused cyber threats on organizational level; investigates Estonian library staff awareness of information security and shares recommendations concerning focus areas that should be given more attention in the future.

Design/methodology/approach

The data used in this paper is based on an overview of relevant literature highlighting the theoretical points and giving the reasons why human factor is considered the weakest link in information security and cyber security and studying how to mitigate the related risks in the organisation. To perform the survey, a web questionnaire was designed which included 63 sentences and was developed based on the knowledge-attitude-behaviour (KAB) model supported by Kruger and Kearney and Human Aspects of Information Security Questionnaire (HAIS-Q) designed by Parsons et al.

Findings

The research results show that the information security awareness of library employees is at a good level; however, awareness in two focus areas needs special attention and should be improved. The output of this study is the mapping of seven focus areas of information security policy in libraries based on the HAIS-Q framework and the KAB model.

Originality/value

The cyber awareness of library employees has not been studied in the world using HAIS-Q and KAB model, and to the best of the authors’ knowledge, no research has been previously carried out in the Estonian library context into cyber security awareness.
Contextualised dictionary literacy, information literacy and information behaviour in the e-environment
Authors: Bothma Theo J.D. , Fourie Ina
Published: February 2024

Purpose

Needs for information literacy, disparities in society, bridging digital divides, richness of information sources in electronic (e-)environments and the value of dictionaries have often been propagated. To improve information sources and information literacy training, information behaviour must be understood (i.e. all information activities). This paper conceptualises new opportunities for information sources (e.g. electronic dictionaries) to all society sectors, dictionary literacy and research lenses such as lexicography to supplement information literacy and behaviour research.

Design/methodology/approach

A scoping review of information literacy and behaviour, lexicography and dictionary literature grounds the conceptualisation of dictionary literacy, its alignment with information literacy, information activities and information behaviour and lexicography as additional research lens.

Findings

Research lenses must acknowledge dictionary use in e-environments, information activities and skills, meanings of information and dictionary literacy, the value of e-dictionaries, alignment with information behaviour research that guides the development of information sources and interdisciplinary research from, e.g. lexicography – thus contextualisation.

Research limitations/implications

Research implications – information behaviour and information literacy research can be enriched by lexicography as research lens. Further conceptualisation could align information behaviour, information literacy and dictionary literacy.

Practical implications

Dictionary training, aligned with information literacy training, can be informed by this paper.

Social implications

The value of dictionary literacy for all sectors of societies can be improved.

Originality/value

Large bodies of literature on information behaviour and lexicography individually do not cover combined insights from both.
Offshoring, hierarchical control and transnational and dynamic environments
Authors: Lin Liang-Hung , Ho Yu-Ling
Published: February 2024

Purpose

This study aims to examine the effect of exploratory innovation offshoring on the level of hierarchical control and how this effect is moderated by transnational and dynamic environments.

Design/methodology/approach

This study draws on a sample of 148 Taiwanese multinational enterprises to examine their governance decisions on foreign investments.

Findings

Findings show that the more innovation offshoring is exploratory, the higher the level of hierarchical control will be used by multinational enterprises (MNEs) and that transnational and dynamic environments have different moderation effects on the positive exploratory innovation offshoring-hierarchical control relationship.

Research limitations/implications

This study has two theoretical implications. First, this study extends the concept of complexity from a transaction attribute level (problem) to an environmental level (transnational environment) and finds that exploratory innovation offshoring and transnational environments interactively impact governance choices. Second, this study distinguishes between two sources of technological uncertainty – uncertainty due to transaction-level attributes (exploratory innovation offshoring) and external environments (dynamic environments) and finds that exploratory innovation offshoring and dynamic environments interactively impact governance choices.

Practical implications

The practical implication of this study lies in the simultaneous consideration of exploratory innovation offshoring and transnational/dynamic environments, which will allow international decision-makers to adjust/select the governance forms most appropriate for speedy responding to and handling environmental changes.

Originality/value

This study employs the theoretical perspectives of transaction cost economics (TCE) and resource-based view (RBV) to analyze and discuss the impact of operational environments – transnational and dynamic environments – on MNEs’ decisions on the governance structure for a given innovation offshoring.