bluuebunny/crossref_metadata_2025 huggingface dataset:
A HYBRID INTEGRO-DIFFERENTIAL EQUATION AND NETWORK BASED MODEL OF EPIDEMICS
Authors: Duclos Ted , Reichert Tom
Published: April 2024

A closed form solution of the full Kermack and McKendrick integro-differential equations (Kermack and McKendrick 1927), called the KMES, is presented and verified. The solution is derived by combining network concepts with the integro-differential equations.

This solution has two parameters: one describing disease transmissibility and a second characterizing population interactions. The verified solution leads directly to useful, previously unknown, analytical expressions which characterize an epidemic. These include novel expressions for the effective reproduction number, time to peak in new infections, and the final size.

Using COVID -19 data from six countries, the transmissibility parameter is estimated and subsequently used to estimate the normalized contagiousness of an individual, a close approximation to viral shedding measured in infected persons. The population interaction parameter is estimated using the Google Residential Mobility Measure. With these parameter estimations, the KMES accurately projects case data from the COVID-19 pandemic in six countries over a 60-day period with R2values above 0.85.

As to performance over longer periods, the KMES projects the Covid-19 total case data from the United States 21 days in advance over an 18-month period with a Mean Absolute Percentage Error of 4.1%. The KMES also accurately identifies the beginnings and peaks of outbreaks within multi month periods in case data from 4 countries.
α-Aminooxyacetic acid derivatives acting as pro-drugs againstMycobacterium tuberculosis
Authors: Vill Kristin , van Geelen Lasse , Michel Oliver , Kiffe-Delf Anna-Lene , Berger Alexander , Podlesainski David , Stenzel Katharina , Kovacic Filip , Lungerich Beate , Burkhardt Björn , Crooks Taylor A. , Howe Michael D. , Ostrer Lev , Jia Ziyi , Ioerger Thomas R. , Kaschani Farnusch , Kaiser Markus , Baughn Anthony D. , Kurz Thomas , Kalscheuer Rainer
Published: April 2024

Tuberculosis (TB), a significant cause of mortality globally, continues to claim 1.5 million lives each year. Despite recent advances in TB management, the emergence of multidrug-resistant strains of TB is exacerbating the treatment of TB. Therefore, there is an immediate necessity to uncover new anti-TB compounds with unprecedented targets. This study introduces novel antimycobacterial molecules that are based on α-aminooxyacetic acid core structures. The lead compounds KSK-104 and KSK-106 displayed potent sub-micromolar antibacterial activity againstMycobacterium tuberculosisH37Rv and XDR clinical isolates, while exhibiting virtually no cytotoxicity against various human cells. Complementation experiments following whole genome sequencing of spontaneously resistant mutants generated against these bactericidal compounds suggested that they are pro-drugs that are intracellularly hydrolyzed by one or both of two specific amidohydrolases, Rv0552 and AmiC. Furthermore, proteomic and transcriptomic analyses of stressed cells and genetic interaction mapping employing transposon insertion sequencing suggest a “dirty drug” mechanism that involves the simultaneous attack of the various drug cleavage products on multiple intracellular targets. Our results suggest a primary role of the pyridoxal 5’-phosphate (PLP) synthesis and salvage pathway and/or PLP-dependent enzymes, the oxidative stress network, and the largely uncharacterizedRv3092c-Rv3095gene cluster in the mode of action.
Massively parallel identification of single-cell immunophenotypes
Authors: Cienciala Martin , Alvarez Laura , Berne Laura , Chena David , Fikar Pavel , Holubova Monika , Kasl Hynek , Lysak Daniel , Luo Mona , Novackova Zuzana , Ordonez Sheyla , Sramkova Zuzana , Vlas Tomas , Georgiev Daniel
Published: April 2024

Translating insights from single-cell analysis into actionable indicators of health and disease requires large-scale confirmatory studies. We introduce biocytometry, a novel method utilizing engineered bioparticles for multiparametric immunophenotyping in suspension, enabling simultaneous measurement across thousands of assays with single-cell sensitivity and a wide dynamic range (1 to 1,000 target cells/sample). The technical validation of biocytometry revealed strong alignment with established technologies (mean bias = 0.25%, LoA = −1.83% to 2.33%) for low-sensitivity settings. Biocytometry excelled in high-sensitivity settings, consistently showcasing superior sensitivity and specificity (LoB = 0), irrespective of the sample type. By employing multiparametric target cell identification, we harnessed the homogeneous assay workflow to discern cell-specific apoptosis in mixed cell cultures. Potential applications include monitoring rare premalignant subpopulations in indications such as smoldering multiple myeloma (SMM), enhancing the detection of circulating tumor cells (CTCs), advancing pharmacokinetic assessments in chimeric antigen receptor (CAR) T-cell therapies, and improving the accuracy of minimal residual disease (MRD) evaluations. Additionally, the high throughput and cell-specific readout capabilities might provide substantial value in drug development, especially for the analysis of complex sample matrices, such as primary cell cultures and organoids.
Transcriptional cascades during fasting amplify gluconeogenesis and instigate a secondary wave of ketogenic gene transcription
Authors: Goldberg Dana , Buchshtab Nufar , Charni-Natan Meital , Goldstein Ido
Published: April 2024

Background & Aims

During fasting, bodily homeostasis is maintained due to hepatic production of glucose (gluconeogenesis) and ketone bodies (ketogenesis). The main hormones governing hepatic fuel production are glucagon and glucocorticoids that initiate transcriptional programs aimed at supporting gluconeogenesis and ketogenesis.

Methods

Using primary mouse hepatocytes as an ex vivo model, we employed transcriptomic analysis (RNA-seq), genome-wide profiling of enhancer dynamics (ChIP-seq), perturbation experiments (inhibitors, shRNA), hepatic glucose production measurements and computational analyses.

Results

We found that in addition to the known metabolic genes transcriptionally induced by glucagon and glucocorticoids, these hormones induce a set of genes encoding transcription factors (TFs) thereby initiating transcriptional cascades. Upon activation by glucocorticoids, the glucocorticoid receptor (GR) induced the genes encoding two TFs: CCAAT/enhancer-binding protein beta (C/EBPβ) and peroxisome proliferator-activated receptor alpha (PPARα). We found that C/EBPβ mainly serves as an amplifier of hormone-induced gene programs in hepatocytes. C/EBPβ augmented gluconeogenic gene expression and hepatic glucose production. Conversely, the GR-PPARα cascade initiated a secondary transcriptional wave of genes supporting ketogenesis. The cascade led to synergistic induction of ketogenic genes which is dependent on protein synthesis. Genome-wide analysis of enhancer dynamics revealed numerous enhancers activated by the GR-PPARα cascade. These enhancers were proximal to ketogenic genes, enriched for the PPARα response element and showed increased PPARα binding.

Conclusion

This study reveals abundant transcriptional cascades occurring during fasting. These cascades serve two separated purposes: the amplification of the primary gluconeogenic transcriptional program and the induction of a secondary gene program aimed at enhancing ketogenesis.
Regulation of ADP-ribosyltransferase activity by ART domain dimerization in PARP15
Authors: Ebenwaldner Carmen , García Saura Antonio Ginés , Ekström Simon , Bernfur Katja , Schüler Herwig
Published: April 2024

PARP15 is a mono-ADP-ribosyltransferase with unknown functions. Its evolutionary relationship with PARP14 suggests roles in antiviral defense; its ability to modify RNA and localization to stress granules point to functions in the regulation of translation. PARP15 also modifies itself and other proteins using its ADP-ribosyltransferase (ART) domain and contains two macrodomains predicted to bind ADP-ribosyl on targets. We used biochemical and biophysical analysis to study how the ADP-ribosyltransferase activity of PARP15 is regulated. Here we show that the catalytic domain of PARP15 dimerizes with mid-nanomolar affinity, forming the same dimer interface in solution that had already been captured by X-ray crystallography of the domain. Furthermore, we show that the formation of dimers is a prerequisite for catalytic activity and that monomeric mutant variants of the domain were catalytically inactive. Our findings suggest a regulatory mechanism by which dimerization is linked to either target engagement or placement of a catalytic residue, rather than NAD+ co-substrate binding, and by which the two protomers of the dimer operate independent of one another. Together, our results uncover a novel mechanism of regulation in a PARP family enzyme, which might inspire new avenues of pharmacological intervention.
Mapping the Human Proteome with Physical Access to DNA
Authors: Trendel Jakob , Trendel Simon , Sha Shuyao , Küster Bernhard
Published: April 2024

In a human cell, DNA is packed in histones, RNA, and chromatin-associated proteins, forming a cohesive gel. At any given moment, only a specific subset of the proteome has physical access to the DNA and organizes its structure, transcription, replication, repair and other molecular functions essential to the way the genome is read and maintained. We have developed a ‘zero-distance’ photo-crosslinking approach to quantify proteins in direct contact with DNA in living cells. Collecting DNA interactomes from human breast cancer cells, we present an atlas of over one thousand proteins with physical access to DNA, and hundreds of peptide-nucleotide crosslinks pinpointing protein-DNA interfaces with single amino-acid resolution. Differential comparisons of DNA interactomes from cells undergoing treatment with estrogen or genotoxic chemotherapy recapitulated the recruitment of key transcription factors and DNA damage proteins. This opens a direct way to explore genomic regulation in a hypothesis-free manner, applicable to many organisms and systems.
Distinct genetic pathways to music enjoyment
Authors: Bignardi Giacomo , Wesseldijk Laura W. , Mas-Herrero Ernest , Zatorre Robert. J. , Ullén Fredrik , Fisher Simon E. , Mosing Miriam A.
Published: April 2024

Humans engage with music for various reasons that range from emotional regulation and relaxation to social bonding. While there are large inter-individual differences in how much humans enjoy music, little is known about the origins of those differences. Here, we disentangled the genetic factors underlying such variation. We collected behavioural data on several facets of music reward sensitivity, music perceptual ability, and general reward sensitivity from a large sample of Swedish twins (N= 9,169). We found that genetic factors substantially explain variance in music reward sensitivity above and beyond genetic influences shared with music perception and general reward sensitivity. Furthermore, multivariate analyses showed that genetic influences on the different facets of music reward sensitivity are partly distinct, uncovering distinct pathways to music enjoyment and different patterns of genetic associations with objectively assessed music perceptual abilities. These results paint a complex picture in which partially distinct sources of genetic variation contribute to different aspects of musical enjoyment and open up new possibilities for using inter-individual differences to gain insights into the biology of a key aspect of human behaviour.
A conserved phenylalanine motif among Teleost fish provides insight for improving electromagnetic perception
Authors: Ricker Brianna , Castellanos Franco E. Alejandro , de los Campos Gustavo , Pelled Galit , Gilad Assaf A.
Published: April 2024

Magnetoreceptive biology as a field remains relatively obscure; compared to the breadth of species believed to sense magnetic fields, it remains under-studied. Here, we present grounds for the expansion of magnetoreception studies among Teleosts. We begin with the electromagnetic perceptive gene (EPG) fromKryptopterus vitreolusand expand to identify 72 Teleosts with homologous proteins containing a conserved three-phenylalanine (3F) motif. Phylogenetic analysis provides insight as to how EPG may have evolved over time, and indicates that certain clades may have experienced a loss of function driven by different fitness pressures. One potential factor is water type with freshwater fish significantly more likely to possess the functional motif version (FFF), and saltwater fish to have the non-functional variant (FXF). It was also revealed that when the 3F motif from the homolog ofBrachyhypopomus gauderio(B.g.) is inserted into EPG – EPG(B.g.) – the response (as indicated by increased intracellular calcium) is faster. This indicates that EPG has the potential to be engineered to improve upon its response and increase its utility to be used as a controller for specific outcomes.
SFRP1 upregulation causes hippocampal synaptic dysfunction and memory impairment
Authors: Pereyra Guadalupe , Mateo María Inés , Martin-Bermejo María Jesús , Miaja Pablo , Klaassen Remco , Gruart Agnès , Rueda-Carrasco Javier , Fernández-Rodrigo Alba , López-Merino Esperanza , Esteve Pilar , Esteban José A. , Smit August B. , Delgado-García José M. , Bovolenta Paola
Published: April 2024

Decreased dendritic complexity and impaired synaptic function are strongly linked to cognitive decline in Alzheimer’s disease (AD), and precede the emergence of other neuropathological traits that establish a harmful cycle exacerbating synaptic dysfunction. SFRP1, a glial-derived protein regulating cell-cell communication, is abnormally elevated in the brain of AD patients and related mouse models already at early disease stages. Neutralization of SFRP1 activity in mice reduces the occurrence of protein aggregates, neuroinflammation and prevents the loss of synaptic long-term potentiation (LTP). In this study, we generated transgenic mice that overexpressSfrp1in astrocytes to investigate whether LTP loss is due to an early influence of SFRP1 on synaptic function or results from other alterations driving disease progression. We report that SFRP1-overexpressing mice show reduced dendritic complexity and spine density in dentate gyrus granule cells during early adulthood, prior to a significant deficit in LTP response and late onset cognitive impairment. Ultrastructural analysis revealed the loss of small-sized synapses and presynaptic alterations in transgenic mice. Analysis of proteomic changes points to a general decrease in protein synthesis and modifications in the synaptic proteome, particularly of proteins related to synaptic vesicle cycle and synaptic organizers, like neurexin and neuroligin. We propose a model wherein SFRP1 directly impacts on synaptic function, by increasing the availability of synaptic organizing molecules at the synapse. These observations, combined with documented SFRP1 effects on APP processing and microglial activation, imply that SFRP1 contributes to multiple pathological effects in AD, emerging as a promising therapeutic target for this devastating disease.
Disinhibition enables vocal repertoire expansion after a critical period
Authors: Heim Fabian , Mendoza Ezequiel , Koparkar Avani , Vallentin Daniela
Published: April 2024

The efficiency of motor skill acquisition is age-dependent, making it increasingly challenging to learn complex maneuvers later in life1–6. Zebra finches, for instance, acquire a complex vocal motor program during a developmental critical period7,8after which the learned song is essentially impervious to modification9. Although inhibitory interneurons are implicated in critical period closure10–13, it is unclear whether manipulating them can reopen heightened motor plasticity windows. Using pharmacology and a novel cell-type specific optogenetic approach, we manipulated inhibitory neuron activity in a premotor area of adult zebra finches beyond their critical period. When exposed to auditory stimulation in the form of novel song, manipulated birds added new vocal syllables to their stable song sequence. By lifting inhibition in a premotor area during sensory experience, we reintroduced vocal plasticity, promoting an expansion of the syllable repertoire without compromising pre-existing song production. Our findings provide insights into motor skill learning capacities, offer potential for motor recovery after injury, and suggest avenues for treating neurodevelopmental disorders involving inhibitory dysfunctions.
Detailed phenotyping ofTbr1-2A-CreERknock-in mice demonstrates significant impacts on TBR1 protein levels and axon development
Authors: Co Marissa , O’Brien Grace K. , Wright Kevin M. , O’Roak Brian J.
Published: April 2024

Spatiotemporal control of Cre-mediated recombination has been an invaluable tool for understanding key developmental processes. For example, knock-in ofCreinto cell type marker gene loci drivesCreexpression under endogenous promoter and enhancer sequences, greatly facilitating the study of diverse neuronal subtypes in the cerebral cortex. However, insertion of exogenous DNA into the genome can have unintended effects on local gene regulation or protein function that must be carefully considered. Here, we analyze a recently generatedTbr1-2A-CreERknock-in mouse line, where a2A-CreERcassette was inserted in-frame just before the stop codon of the transcription factor geneTbr1. HeterozygousTBR1mutations in humans and mice are known to cause autism or autism-like behavioral phenotypes accompanied by structural brain malformations, most frequently a reduction of the anterior commissure. Thus, it is critical for modified versions ofTbr1to exhibit true wild-type-like activity. We evaluated theTbr1-2A-CreERallele for its potential impact onTbr1function and complementation toTbr1loss-of-function alleles. In mice with one copy of theTbr1-2A-CreERallele, we identified reduction of TBR1 protein in early postnatal cortex along with thinning of the anterior commissure, suggesting hypersensitivity of this structure to TBR1 dosage. ComparingTbr1-2A-CreERandTbr1-null heterozygous and homozygous mice toTbr1-null complementation crosses showed reductions of TBR1 dosage ranging from 28.4% to 95.9%. Using these combinatorial genotypes, we found that low levels of TBR1 protein (∼16%) are sufficient to establish cortical layer positioning, while greater levels (>50%) are required for normal suppression of layer 5 identity. In total, these results strongly support the conclusion thatTbr1-2A-CreERis a hypomorphic allele. We advise caution when interpreting experiments using this allele, such as transcriptomic studies, considering the sensitivity of various corticogenic processes to TBR1 dosage and the association of heterozygousTBR1mutations with complex neurodevelopmental disorders.
The Flexible, Versatile and Fast GreGT Platform of Fully Deleted Helper-Virus Independent Adenoviral Vectors
Authors: Qi Yan , Zhang Xianghua , Cull Janae Wheeler , Wall Charles , Maslanik William , Staerz Uwe D.
Published: April 2024

Gene transfer (GT) vectors have diverse applications. They have been used to restore cellular activities by reconstituting normal cellular functions, by delivering therapeutic compounds, and by priming immune responses as genetic vaccines. Viruses, nature’s gene delivery vehicles, have formed the basis of most GT vectors. The biology of the underlying virus may, however, hamper their use. For instance, retroviral vectors with their ability to integrate into the genome, may cause malignant transformations. Vectors designed as minor variants of the relatively benign, yet complex adenovirus (Ad) excite vigorous immune responses, thus limiting their therapeutic effects. Deleting Ad vectors of all endogenous Ad genes brought their beneficial features to the front, such as their ability to transduce cells of many types with high efficiency and to deliver large genetic payloads. Earlier production schemes of fully deleted Ad (fdAd) vectors depended on helper virus constructs to deliver the vector production informationin trans. They suffered from contaminations with the helper virus or the recombination of replication competent adenoviruses (RCA). We previously developed a novel transfection-based helper virus-independent Ad vector encapsidation technology that avoided these pitfalls. It was built on a vector genome and a vector packaging module. We have now optimized our approach into the GreGTplug-and-playplatform so that a new vector can be delivered in about four weeks. The GreGT system is built upon a set of base vector genome modules that can be quickly loaded with a new application, and a set of packaging modules that allow their encapsidation into capsids of different Ad serotypes. As both components can be freely combined, the GreGT platform is endowed with high degrees of flexibility and versatility. Finally, the deletion of all endogenous Ad genes from the vector genome limits the interference by anti-Ad immune responses. It also increases the genetic payload capacity to levels unique to this system.
iSWAP-type
geometric gates induced by paths on the Schmidt sphere
Authors: Saarijärvi Max Johansson , Sjöqvist Erik
Published: April 2024

We propose iSWAP-type quantum gates based on geometric phases purely associated with paths on the Schmidt sphere []. These can entangle qubit pairs to an arbitrary degree; in particular, they can create maximally entangled states from product states by an appropriate choice of base point on the Schmidt sphere. We identify Hamiltonians that generate pure paths on the Schmidt sphere by reverse engineering and demonstrate explicitly that the resulting Hamiltonians can be implemented in systems of transmon qubits. The geometric Schmidt gates are characterized by vanishing dynamical phases and are complementary to geometric single-qubit gates that take place on the Bloch sphere.

Published by the American Physical Society
2024
QCD analysis of the
P
-wave charmonium electromagnetic Dalitz decays
hc→η(′)ℓ+ℓ−
Authors: Fan Chao-Jie , He Jun-Kang
Published: April 2024

The P-wave charmonium electromagnetic Dalitz decays hc→η(′)ℓ+ℓ− (ℓ=e,μ) with large recoil momentum are investigated in the framework of perturbative QCD, and the contributions from the small-recoil-momentum region are described by the overlap of soft wave functions. The transition form factors fhcη(′)(q2) and the normalized transition form factors Fhcη(′)(q2) in full kinematic region are derived for the first time. It is noticed that there are no IR divergences at the one-loop level, and the transition form factors with the relativistic corrections from the internal momentum of hc are insensitive to both the shapes of η(′) distribution amplitudes and the invariant mass of the lepton pair in the large-recoil-momentum region. Intriguingly, unlike the situation in the S-wave charmonium decays J/ψ→η(′)ℓ+ℓ−, we find that the contributions from the small-recoil-momentum region are comparable with those from the large-recoil-momentum region in the P-wave charmonium decays hc→η(′)ℓ+ℓ−. By employing the obtained Fhcη(′)(q2), we give predictions of the branching ratios B(hc→η(′)ℓ+ℓ−), which may come within the range of measurement of present or near-future experiments.

Published by the American Physical Society
2024
Iteration on the Higgs portal for vector dark matter and its effective field theory description
Authors: Arcadi Giorgio , Criado Juan Carlos , Djouadi Abdelhak
Published: April 2024

We reanalyze the effective field theory (EFT) approach for the scenario in which the particles that account for the dark matter (DM) in the universe are vector states that interact only through the Standard Model-like Higgs boson. These DM particles are searched for in direct and indirect detection in astrophysical experiments and in invisible Higgs decays at the LHC. The constraints obtained in these two search types are complementary and correlated. In recent years, it has been advocated that the EFT approach is problematic for small DM mass and that it does not capture all the aspects of vector DM; one should thus rather interpret the searches in ultraviolet complete theories that are more realistic. In this paper, we show that a more appropriate definition of the EFT with the introduction of an effective new physics scale parameter, can encompass such issues. We illustrate this by matching the EFT to two examples of ultraviolet completions for it: the U(1) model with a dark photon and a model that was recently adopted by the LHC experiments in which vectorlike fermions generate an effective interaction between the Higgs and the DM states at the one-loop level. Additionally, we find that the region of parameter space that is relevant for DM phenomenology is well inside the range of validity of the EFT. It thus provides a general parametrization of the effects of any ultraviolet model in the regime under exploration, making it the ideal framework for model-independent analyses of the vector DM Higgs-portal.

Published by the American Physical Society
2024
Stringy spacetime uncertainty principle and a modified trans-Planckian censorship criterion
Authors: Brandenberger Robert , Ho Pei-Ming , Kawai Hikaru , Shao Wei-Hsiang
Published: April 2024

We study the implications of the stringy spacetime uncertainty relation (STUR) for inflationary cosmology. By demanding that no fluctuation modes that exit the Hubble radius are affected by the nonlocality resulting from the STUR, we find an upper bound on the number of e-foldings of inflation. The bound is a factor of 2 weaker than what results from the trans-Planckian censorship criterion (TCC). By demanding that the inflationary phase is simultaneously consistent with STUR and sufficiently long for inflation to provide a causal explanation of structure on the scale of the current Hubble radius, we find an upper bound on the energy scale of inflation. The bound is less restrictive than what follows from the TCC, but it remains in conflict with canonical single-field inflation models.

Published by the American Physical Society
2024
Positivity of the hypergeometric Veneziano amplitude
Authors: Rigatos Konstantinos C.
Published: April 2024

Recently, an infinite family of one-parameter generalizations of the Veneziano amplitude were bootstrapped using as input assumptions an integer mass spectrum, crossing symmetry, high-energy boundedness, and exchange of finite spins. This new result was dubbed the hypergeometric Veneziano amplitude, with a real-valued deformation parameter r. For concreteness we work in a setup where the lowest-mass state is a tachyon of mass m02=−1 and using the partial-wave decomposition and the positivity of said decomposition’s coefficients we are able to bound the deformation parameter to r≥0 and, also, to obtain an upper bound on the number of spacetime dimensions D≤26, which is the critical dimension of bosonic string theory.

Published by the American Physical Society
2024
Validation of the Wiedemann-Franz Law in Solid and Molten Tungsten above 2000 K through Thermal Conductivity Measurements via Steady-State Temperature Differential Radiometry
Authors: Milich Milena , Schonfeld Hunter B. , Boboridis Konstantinos , Robba Davide , Vlahovic Luka , Konings Rudy J. M. , Braun Jeffrey L. , Gaskins John T. , Bhatt Niraj , Giri Ashutosh , Hopkins Patrick E.
Published: April 2024

We measure the thermal conductivity of solid and molten tungsten using steady state temperature differential radiometry. We demonstrate that the thermal conductivity can be well described by application of Wiedemann-Franz law to electrical resistivity data, thus suggesting the validity of Wiedemann-Franz law to capture the electronic thermal conductivity of metals in their molten phase. We further support this conclusion using molecular dynamics simulations with a machine-learned potential. Our results show that at these high temperatures, the vibrational contribution to thermal conductivity is negligible compared to the electronic component.

Published by the American Physical Society
2024
Testing quantum reasoning: Developing, validating, and application of a questionnaire
Authors: Waitzmann Moritz , Scholz Ruediger , Wessnigk Susanne
Published: April 2024

Clear and rigorous quantum reasoning is needed to explain quantum physical phenomena. As pillars of true quantum physical explanations, we suggest specific quantum reasoning derived from quantum physical key ideas. An experiment is suggested to support such a quantum reasoning, in which a quantized radiation field interacts with an optical beam splitter, leading to experimental results conflicting with classical physical predictions. The results, however, can be explained consistently with a quantum reasoning based on the key ideas of probability, superposition, and interference (PSI). In this quantum optical key experiment the optical beam splitter prepares a superposition of single photon states and a Michelson interferometer is used to detect the superposition via controlled propagation phases. Although different single photon experimental setups (aimed at helping students to gain access to foundational issues in quantum physics) have been discussed in the past, the wave-particle dualism bound to classical physics maintains its predominance as an explanation pattern for the interpretation of these experiments. The study presented here investigates the effect of the quantum optical key experiment on the ability of students to use quantum reasoning based on the key ideas of PSI to overcome the naive wave-particle dualism. The current state of relevant studies that test student access to quantum physics can roughly be divided into two distinct areas: one tests how mathematical abilities help them to understand quantum physics and one tests how nonmathematical representations of a set of specific quantum theoretical traits (“Wesenszüge”) lead to a deeper understanding of quantum physics. There is a lack of questionnaires that focus on the idea of developing quantum reasoning based on superposition, probability, and interference of quantum states combined with a real experiment using true quantum light. In the first part of the article, we describe the physical modeling and present the development of the questionnaire. The set of items has been constructed from newly developed items and combined with well-tested ones. The validation of the set addresses qualitative and quantitative methods. In the second part, we give a pre- and poststudy examination of the impact of the quantum optical key experiment on students’ quantum reasoning. A significant increase in the number of students using quantum arguments is based on PSI reasoning for the explanation of an interference, such as the behavior of single photon states. Though the increase is significant, we found only minor changes in a particular issue to the students’ reasoning when approaching quantum physics as illustrated by a sample of answers given in the second part of the article. The concept of quantum states and the principle of superposition still appear particularly difficult.

Published by the American Physical Society
2024
Cooling dynamics of a free ion in a Bose-Einstein condensate
Authors: Oghittu Lorenzo , Simonet Juliette , Wessels-Staarmann Philipp , Drescher Markus , Sengstock Klaus , Mathey Ludwig , Negretti Antonio
Published: April 2024

We investigate the dynamics of an ion moving through a homogeneous Bose-Einstein condensate (BEC) after an initial momentum is imparted. For this, we derive a master equation in the weak-coupling limit and Lamb-Dicke approximation for the reduced density matrix of the ion. We study the time evolution of the ion's kinetic energy and observe that its expectation value, identified as the ion temperature Tion, is reduced by several orders of magnitude in a time on the order of microseconds for a condensate density in the experimentally relevant range between 1013cm−3 and 1014cm−3. We characterize this behavior by defining the duration at half maximum as the time required by Tion to reach half of its initial value, and study its dependence on the system parameters. Similarly, we find that the expectation value of the ion's momentum operator is reduced by nine orders of magnitude on the same timescale, making the ion's position converge to a final value. Based on these results, we conclude that the interaction with the bosonic bath allows for cooling and pinning of the ion by decreasing the expectation value of its kinetic energy and velocity, which constitutes a result of direct relevance for current atom-ion experiments.

Published by the American Physical Society
2024
Impact of feedback time-distribution on laser dynamics
Authors: Skënderas Martin , Jolly Spencer W. , Virte Martin
Published: April 2024

Time-distributed optical feedback in semiconductor lasers has gained attention for its ability to produce high-quality chaos and effectively suppress the time delay signature. However, the fundamental impact of the distribution of feedback in time on laser dynamics remains unexplored. In this paper, we investigate this topic by using fiber Bragg grating (FBG) feedback. We theoretically study the laser response using FBGs of different lengths but similar reflectivity, effectively stretching the impulse response over a longer period while maintaining its overall shape. We observe that there is a critical value of a grating length where fluctuations in laser stability emerge. We attribute this phenomenon to the damping of relaxation oscillations when the zeros of the FBG reflectivity spectrum align with the laser side lobes around the relaxation oscillation frequency. We also uncover an asymmetrical dynamical behavior of the laser for positive and negative frequency detuning. We deduce that this asymmetry is a characteristic feature of FBG feedback and delve into the specificities that trigger such behavior.

Published by the American Physical Society
2024
Hybrid optomechanical superconducting qubit system
Authors: Manninen Juuso , Blick Robert H. , Massel Francesco
Published: April 2024

We propose an integrated nonlinear superconducting device based on a nanoelectromechanical shuttle. The system can be described as a qubit coupled to a bosonic mode. The topology of the circuit gives rise to an adjustable qubit-mechanical coupling, allowing the experimenter to tune between linear and quadratic coupling in the mechanical degrees of freedom. Owing to its flexibility and potential scalability, the proposed setup represents an important step towards the implementation of bosonic error correction with mechanical elements in large-scale superconducting circuits. We give preliminary evidence of this possibility by discussing a simple state-swapping protocol that uses this device as a quantum memory element.

Published by the American Physical Society
2024
Chiral excitations and the intermediate-field regime in the Kitaev magnet
α−RuCl3
Authors: Sahasrabudhe Anuja , Prosnikov Mikhail A. , Koethe Thomas C. , Stein Philipp , Tsurkan Vladimir , Loidl Alois , Grüninger Markus , Hedayat Hamoon , van Loosdrecht Paul H. M.
Published: April 2024

In the Kitaev magnet α-RuCl3, the existence of a magnetic-field-induced quantum spin-liquid phase and of anyonic excitations is controversially discussed. We address this elusive, exotic phase via helicity-dependent Raman scattering and analyze the Raman optical activity of excitations as a function of magnetic field and temperature. The hotly debated field regime between 7.5 and 10.5T is characterized by clear spectroscopic signatures such as a plateau of the Raman optical activity of the dominant, chiral spin-flip excitation. This provides direct evidence for the existence of a distinct intermediate-field regime with an intriguing ground state featuring chiral excitations.

Published by the American Physical Society
2024
Hedging price risk through commodity derivatives: a case of Sethi Jewellers
Authors: Soni Tarun Kumar
Published: April 2024

Learning outcomes

After completion of the case study, the students will be able to understand the different risks associated with a business, focusing on price risk and the importance of price risk management in business; understand and evaluate the products available for hedging price risk through exchange-traded derivatives in the Indian scenario; and understand and evaluate the different strategies for price risk management through exchange-traded derivatives in the Indian scenario.

Case overview/synopsis

The case study pertains to a small business, M/s Sethi Jewellers. The enterprise is being run by Shri Charan Jeet Sethi and his son Tejinder Sethi. The business is located in Jain Bazar, Jammu, UT, in Northern India. The business was started in 1972 by Charan Jeet’s father. They deal in a wide range of jewelry products and are well-established jewelers known for selling quality ornaments. Tejinder (MBA in marketing) was instrumental in revamping his business recently. Under his leadership, the business has experienced rapid transformation. The business has grown from a one-room shop fully managed by Tejinder’s grandfather to a multistory showroom with several artisans, sales staff and security persons. Through his e-store, Tejinder has a bulk order from a client where the client requires him to accept the order with a small token at the current price and deliver the final product three months from now. Tejinder is in a dilemma about accepting or rejecting the large order. Second, if he accepts, should he buy the entire gold now or wait to buy it later at a lower price? He is also considering hedging the price risk through exchange-traded derivatives. However, he is not entirely sure, as he has a few apprehensions regarding the same, and he is also not fully aware of the process and the instruments he has to use for hedging the price risk on the exchange.

Complexity academic level

The case study is aimed to cater to undergraduate, postgraduate and MBA students in the field of finance. This case study can be used for students interested in commodity derivatives, risk management and market microstructure.

Supplementary materials

Teaching notes are available for educators only.

Subject code

CSS 1: Accounting and finance.
Curse or blessing? Students’ experience from ChatGPT with an application of Colaizzi’s phenomenological descriptive method of enquiry and content analysis
Authors: Awal Md. Rabiul , Asaduzzaman
Published: April 2024

Purpose

This qualitative work aims to explore the university students’ attitude toward advantages, drawbacks and prospects of ChatGPT.

Design/methodology/approach

This paper applies well accepted Colaizzi’s phenomenological descriptive method of enquiry and content analysis method to reveal the ChatGPT user experience of students in the higher education level.

Findings

The study’s findings indicate that ChatGPT enhances the quality of learning and facilitates faster learning among university students. However, despite numerous positive outcomes, it is noted that ChatGPT may diminish students' creativity by swiftly addressing their critical queries. Over time, students may experience a decline in patience and critical thinking skills as they excessively rely on ChatGPT, potentially leading to ethical misconduct.

Originality/value

This paper primarily explores the advantages and drawbacks of using ChatGPT in the university context of Bangladesh. The present study creates a platform for future research in this domain with comprehensive study design. The study results alert the policy makers to improve upcoming version of ChatGPT with convenient user experience and academicians as this paper unleash several positive as well as negative consequences of using this AI-enabled chatbot.
Effect of carbon nanotube fiber on shielding effectiveness of stainless-steel electromagnetic shielding fabric
Authors: Liu Zhe , Yang Yichen , Wang Xiuchen
Published: April 2024

Purpose

Stainless-steel electromagnetic shielding (EMS) fabrics are widely applied as protective materials against electromagnetic interference (EMI). However, these fabrics primarily shield electromagnetic waves through reflection, which can lead to the formation of resonance effects that severely compromise their protective capabilities and potentially cause secondary electromagnetic pollution in the external environment.

Design/methodology/approach

In this paper, carbon nanotube fibers are added via spacing method to replace some stainless-steel fibers to impart absorbing properties to stainless-steel EMS fabric. The shielding effectiveness (SE) of the EMS fabrics across various polarization directions is analyzed. Additionally, a spacing arrangement for the carbon nanotube fibers is designed. The EMS fabric with carbon nanotube fibers is manufactured using a semi-automatic sample loom, and its SE is tested using a small window method test box in both vertical and horizontal polarization directions.

Findings

According to the experimental data and electromagnetic theory analysis, it is determined that when the spacing between the carbon nanotube fibers is less than a specific distance, the SE of the stainless-steel EMS fabric significantly improves. The fabric exhibits stable absorbing properties within the tested frequency range, effectively addressing the issue of secondary damage that arises from relying solely on reflective shielding. Conversely, as the spacing between the carbon nanotube fibers exceeds this distance, the SE diminishes. Notably, the SE in the vertical polarization direction is substantially higher than that in the horizontal polarization direction at the same frequency.

Originality/value

This study provides a new path for the development of high-performance EMS fabrics with good wave-absorption characteristics and SE.
Examining the effect of gamification mobile app on conference engagement: an integration of S-O-R framework and UGT
Authors: Jung Shinyong , Lee Seonjeong (Ally) , Leitch Stephen
Published: April 2024

Purpose

By integrating stimulus-organism-response theory and uses and gratifications theory, this study explored the salient gamification factors that satisfy the gratifications of conference attendees in the context of an event gamification mobile app and their relationships with conference engagement, continuance intention and word-of-mouth.

Design/methodology/approach

The questionnaire was developed in Qualtrics and administered on a gamification application called Goosechase during an annual hospitality conference. The proposed hypotheses were tested using the partial least square-structural equation modeling (PLS-SEM).

Findings

The gratifications of social presence, education and entertainment through a gamification mobile app influences attendees’ engagement during the conference while achievement gratification does not. Positive effects of conference engagement on their continuous intention and WOM have been also validated.

Originality/value

By adopting a unique integrated approach that utilizes UGT and S-O-R framework, while considering conference engagement as work-related engagement, this study offers a fresh perspective on gamification apps and discusses its theoretical and practical implications in depth.
An efficient approach for automatic crack detection using deep learning
Authors: Usharani Shola , Gayathri R. , Kovvuri Uday Surya Deveswar Reddy , Nivas Maddukuri , Md Abdul Quadir , Tee Kong Fah , Sivaraman Arun Kumar
Published: April 2024

Purpose

Automation of detecting cracked surfaces on buildings or in any industrially manufactured products is emerging nowadays. Detection of the cracked surface is a challenging task for inspectors. Image-based automatic inspection of cracks can be very effective when compared to human eye inspection. With the advancement in deep learning techniques, by utilizing these methods the authors can create automation of work in a particular sector of various industries.

Design/methodology/approach

In this study, an upgraded convolutional neural network-based crack detection method has been proposed. The dataset consists of 3,886 images which include cracked and non-cracked images. Further, these data have been split into training and validation data. To inspect the cracks more accurately, data augmentation was performed on the dataset, and regularization techniques have been utilized to reduce the overfitting problems. In this work, VGG19, Xception and Inception V3, along with Resnet50 V2 CNN architectures to train the data.

Findings

A comparison between the trained models has been performed and from the obtained results, Xception performs better than other algorithms with 99.54% test accuracy. The results show detecting cracked regions and firm non-cracked regions is very efficient by the Xception algorithm.

Originality/value

The proposed method can be way better back to an automatic inspection of cracks in buildings with different design patterns such as decorated historical monuments.
Investigating resistance to IT projects: a conceptual model from a meta-synthesis approach
Authors: Krishnan Manoj , Krishnan Satish
Published: April 2024

Purpose

The study aims to drive conceptual clarity around resistance to information technology projects, integrating multiple facets of the phenomenon from earlier studies.

Design/methodology/approach

The study conducts a meta-synthesis of qualitative studies on resistance to technology projects; it analyzes those studies at a case-specific level, compares and contrasts emergent concepts against each other, and “translates” those to the rest of the studies. The study uses the seven-step meta-ethnography method by Noblit and Hare to reciprocally translate emergent concepts to construct the conceptual model.

Findings

Through meta-synthesis, the study derives a new conceptual model for resistance to information technology projects, exemplifying how the identified antecedents create user resistance and how the phenomenon progresses within organizations.

Research limitations/implications

This study enriches the observations and conclusions of past individual studies while explicating various facets of the mechanisms that generate and progress technology resistance within organizations. It offers fresh insights into the equivocal nature of the phenomenon and the distinctive ways it progresses from individual to group level.

Practical implications

Many ambitious and costly digital transformation efforts do not succeed due to user resistance. Understanding the mechanisms that create user resistance can help organizations manage technology projects better, thereby reducing the technology assimilation gap and protecting returns on related investments.

Originality/value

There have been extensive studies on technology acceptance (enablers) within organizations, while those relating to technology inhibitors are somewhat limited. However, the symmetry of understanding between enablers and inhibitors is vital for organizations to assimilate promising technologies and transform their business models. This model uses a new lens of sensemaking theory to explain how the antecedents trigger perceived threats and resistance behavior; it highlights the nuances around the development of resistance within individuals and its progression to groups. The resultant model offers better generalizability in organizational contexts.