bluuebunny/crossref_metadata_2025 huggingface dataset:
Distinct H3K9me3 heterochromatin maintenance dynamics govern different gene programs and repeats in pluripotent cells
Authors: Zhang Jingchao , Donahue Greg , Gilbert Michael B. , Lapidot Tomer , Nicetto Dario , Zaret Kenneth S.
Published: September 2024

H3K9me3-heterochromatin, established by lysine methyltransferases (KMTs) and compacted by HP1 isoforms, represses alternative lineage genes and DNA repeats. Our understanding of H3K9me3-heterochromatin stability is presently limited to individual domains and DNA repeats. We engineeredSuv39h2KO mouse embryonic stem cells to degrade remaining two H3K9me3- KMTs within one hour and found that both passive dilution and active removal contribute to H3K9me3 decay within 12-24 hours. We discovered four different H3K9me3 decay rates across the genome and chromatin features and transcription factor binding patterns that predict the stability classes. A “binary switch” governs heterochromatin compaction, with HP1 rapidly dissociating from heterochromatin upon KMTs’ depletion and a particular threshold level of HP1 limiting pioneer factor binding, chromatin opening, and exit from pluripotency within 12 hr. Unexpectedly, receding H3K9me3 domains unearth residual HP1β peaks enriched with heterochromatin-inducing proteins. Our findings reveal distinct H3K9me3-heterochromatin maintenance dynamics governing gene networks and repeats that together safeguard pluripotency.
Striatal indirect pathway mediates hesitation
Authors: Geramita Matthew A , Ahmari Susanne E , Yttri Eric A
Published: September 2024

Determining the best possible action in an uncertain situation is often challenging, and organisms frequently need extra time to deliberate. This pause in behavior in response to uncertainty – also known as hesitation – commonly occurs in many aspects of daily life, yet its neural circuits are poorly understood. Here we present the first experimental paradigm that reliably evokes hesitation in mice. Using cell-type specific electrophysiology and optogenetics, we show that indirect, but not direct, pathway spiny projection neurons specifically in the dorsomedial striatum mediate hesitation. These data indicate that the basal ganglia circuits controlling the pausing involved in cognitive processes like hesitation are distinct from those that control other types of behavioral inhibition, such as cue-induced stopping.
Synaptic Specializations at Dopamine Release Sites Orchestrate Efficient and Precise Neuromodulatory Signaling
Authors: Bulumulla Chandima , Walpita Deepika , Iyer Nirmala , Eddison Mark , Patel Ronak , Alcor Damien , Ackerman David , Beyene Abraham G.
Published: September 2024

Dopamine is a key chemical neuromodulator that plays vital roles in various brain functions. Traditionally, neuromodulators like dopamine are believed to be released in a diffuse manner and are not commonly associated with synaptic structures where pre- and postsynaptic processes are closely aligned. Our findings challenge this conventional view. Using single-bouton optical measurements of dopamine release, we discovered that dopamine is predominantly released from varicosities that are juxtaposed against the processes of their target neurons. Dopamine axons specifically target neurons expressing dopamine receptors, forming synapses to release dopamine. Interestingly, varicosities that were not directly apposed to dopamine receptor-expressing processes or associated with neurons lacking dopamine receptors did not release dopamine, regardless of their vesicle content. The ultrastructure of dopamine release sites share common features of classical synapses. We further show that the dopamine released at these contact sites induces a precise, dopamine-gated biochemical response in the target processes. Our results indicate that dopamine release sites share key characteristics of conventional synapses that enable relatively precise and efficient neuromodulation of their targets.
High-throughput optimized prime editing mediated endogenous protein tagging for pooled imaging of protein localization
Authors: Sanchez Henry M. , Lapidot Tomer , Shalem Ophir
Published: September 2024

The subcellular organization of proteins carries important information on cellular state and gene function, yet currently there are no technologies that enable accurate measurement of subcellular protein localizations at scale. Here we develop an approach for pooled endogenous protein tagging using prime editing, which coupled with an optical readout and sequencing, provides a snapshot of proteome organization in a manner akin to perturbation-based CRISPR screens. We constructed a pooled library of 17,280 pegRNAs designed to exhaustively tag 60 endogenous proteins spanning diverse localization patterns and explore a large space of genomic and pegRNA design parameters. Pooled measurements of tagging efficiency uncovered both genomic and pegRNA features associated with increased efficiency, including epigenetic states and interactions with transcription. We integrate pegRNA features into a computational model with predictive value for tagging efficiency to constrain the design space of pegRNAs for large-scale peptide knock-in. Lastly, we show that combining in-situ pegRNA sequencing with high-throughput deep learning image analysis, enables exploration of subcellular protein localization patterns for many proteins in parallel following a single pooled lentiviral transduction, setting the stage for scalable studies of proteome dynamics across cell types and environmental perturbations.
Quantitative Comparison of Monomeric StayGold Variants Using Protein Nanocages in Living Cells
Authors: Viola Giulia , Jacobs Kyle A. , Lemière Joël , Kutys Matthew L. , Wittmann Torsten
Published: September 2024

To standardize comparison of fluorescent proteins and independently determine which monomeric StayGold variant is best for live microscopy, we analyzed fluorescent protein tagged I3-01 peptides that self-assemble into stable sixty subunit dodecahedrons inside live cells. We find mStayGold is 3-fold brighter and 3-fold more photostable compared with EGFP and superior to other monomeric variants in mammalian cytoplasm. In addition, analysis of intracellular nanocage diffusion confirms the monomeric nature of mStayGold.
An integrated view of the structure and function of the human 4D nucleome
Authors:   4D Nucleome Consortium, Dekker Job , Oksuz Betul Akgol , Zhang Yang , Wang Ye , Minsk Miriam K. , Kuang Shuzhen , Yang Liyan , Gibcus Johan H. , Krietenstein Nils , Rando Oliver J. , Xu Jie , Janssens Derek H. , Henikoff Steven , Kukalev Alexander , Willemin Andréa , Winick-Ng Warren , Kempfer Rieke , Pombo Ana , Yu Miao , Kumar Pradeep , Zhang Liguo , Belmont Andrew S , Sasaki Takayo , van Schaik Tom , Brueckner Laura , Peric-Hupkes Daan , van Steensel Bas , Wang Ping , Chai Haoxi , Kim Minji , Ruan Yijun , Zhang Ran , Quinodoz Sofia A. , Bhat Prashant , Guttman Mitchell , Zhao Wenxin , Chien Shu , Liu Yuan , Venev Sergey V. , Plewczynski Dariusz , Irastorza Azcarate Ibai , Szabó Dominik , Thieme Christoph J. , Szczepińska Teresa , Chiliński Mateusz , Sengupta Kaustav , Conte Mattia , Esposito Andrea , Abraham Alex , Zhang Ruochi , Wang Yuchuan , Wen Xingzhao , Wu Qiuyang , Yang Yang , Liu Jie , Boninsegna Lorenzo , Yildirim Asli , Zhan Yuxiang , Chiariello Andrea Maria , Bianco Simona , Lee Lindsay , Hu Ming , Li Yun , Barnett R. Jordan , Cook Ashley L. , Emerson Daniel J. , Marchal Claire , Zhao Peiyao , Park Peter , Alver Burak H. , Schroeder Andrew , Navelkar Rahi , Bakker Clara , Ronchetti William , Ehmsen Shannon , Veit Alexander , Gehlenborg Nils , Wang Ting , Li Daofeng , Wang Xiaotao , Nicodemi Mario , Ren Bing , Zhong Sheng , Phillips-Cremins Jennifer E. , Gilbert David M. , Pollard Katherine S. , Alber Frank , Ma Jian , Noble William S. , Yue Feng
Published: September 2024

The dynamic three-dimensional (3D) organization of the human genome (the “4D Nucleome”) is closely linked to genome function. Here, we integrate a wide variety of genomic data generated by the 4D Nucleome Project to provide a detailed view of human 3D genome organization in widely used embryonic stem cells (H1-hESCs) and immortalized fibroblasts (HFFc6). We provide extensive benchmarking of 3D genome mapping assays and integrate these diverse datasets to annotate spatial genomic features across scales. The data reveal a rich complexity of chromatin domains and their sub-nuclear positions, and over one hundred thousand structural loops and promoter-enhancer interactions. We developed 3D models of population-based and individual cell-to-cell variation in genome structure, establishing connections between chromosome folding, nuclear organization, chromatin looping, gene transcription, and DNA replication. We demonstrate the use of computational methods to predict genome folding from DNA sequence, uncovering potential effects of genetic variants on genome structure and function. Together, this comprehensive analysis contributes insights into human genome organization and enhances our understanding of connections between the regulation of genome function and 3D genome organization in general.
INVESTIGATION OF SECONDARY METABOLITES PRESENT IN METHANOLIC AND ALKALOIDAL EXTRACTS OF HUNTERIA UMBELLATA LEAVES USING COMPUTATIONAL MOLECULAR NETWORKING TOOL
Authors: Adedeji Rukayat A. , Opemipo Musibau , Babalola Oluwabukunmi , Julius Solomon O. , Alaribe Stephenie C.
Published: September 2024

Background

Plants have long served as a vital source of therapeutic agents in both traditional and orthodox medicine. However, with the shift in drug discovery towards synthetic laboratory compounds, there has also been a decline in the exploration of natural sources for drug development. Research attention needs to be diverted toward natural drug discovery and more importantly, towards the development of new and improved methods of isolating, analyzing, identifying, and characterizing chemical moieties obtained from plants.

Objectives

To investigate the secondary metabolites present in the methanolic and alkaloidal extracts ofHunteria umbellata, a medicinally significant plant, and explore potential links between the identified compounds and the plant’s pharmacological uses.

Methods

Metabolomic technique was employed, utilizing liquid chromatography-tandem mass spectrometry (LC-MS/MS) to separate the components within the extracts. The isolated compounds were then identified based on their mass-to-charge (m/z) ratios. The resulting chromatograms and spectra were analyzed using a computational molecular networking tool to match the m/z values to known compounds in mass spectrometry libraries.

Result

Eighteen compounds were successfully isolated from the methanolic and alkaloidal extracts, including Yohimbine; (-)-Epicatechin; Picrinine; Tubotaiwine; Quercetin-3-O-robinobioside; and Pheophorbide A. Many of these compounds have been previously studied for their clinical relevance, such as antidiabetic, antioxidant, and anti-inflammatory activities, supporting the medicinal uses traditionally attributed to Hunteria umbellata. Notably, the identification of Pheophorbide A, a compound with potential photodynamic therapy applications, opens new avenues for further investigation.

Conclusion

These findings provide significant insight into the bioactive components of Hunteria umbellata, supporting its traditional medicinal uses. The identification of clinically relevant compounds not only validates traditional practices but also highlights the plant’s potential for contributing to modern drug discovery efforts.
High-throughput robotic isolation of human iPS cell clones reveals frequent homozygous induction of identical genetic manipulations by CRISPR-Cas9
Authors: Takahashi Gou , Maeda Minato , Shinozaki Kayoko , Harada Gakuro , Ito Saburo , Miyaoka Yuichiro
Published: September 2024

Genome editing in human iPS cells is a powerful approach in regenerative medicine. CRISPR-Cas9 is the most common genome editing tool, but it often induces byproduct insertions and deletions in addition to the desired edits. Therefore, genome editing of iPS cells produces diverse genotypes. Existing assays mostly analyze genome editing results in cell populations, but not in single cells. However, systematic profiling of genome editing outcomes in single iPS cells was lacking. In this study, we developed a method for high-throughput iPS cell clone isolation based on the precise robotic picking of cell clumps derived from single cells grown in extracellular matrices. We analyzed over 1,000 genome-edited iPS cell clones and found that homozygous editing was much more frequent than heterozygous editing. We also observed frequent homozygous induction of identical genetic manipulations, including insertions and deletions. Our new cloning method and findings will facilitate the application of genome editing to human iPS cells.
Visualizing nuclear pore complex plasticity with Pan-Expansion Microscopy
Authors: Morgan Kimberly J. , Carley Emma , Coyne Alyssa N. , Rothstein Jeffrey D. , Lusk C. Patrick , King Megan C.
Published: September 2024

Cell-type specific and environmentally-responsive plasticity in nuclear pore complex (NPC) composition and structure is an emerging area of investigation, but its molecular underpinnings remain ill defined. To understand the cause and consequence of NPC plasticity requires technologies to visualize differences within individual NPCs across the thousands in a given nucleus. We evaluate the utility of Pan Expansion Microscopy (Pan-ExM), which enables 16-20 fold isotropic cell enlargement while preserving the proteome, to reveal NPC plasticity. NPCs are robustly identified by deep learning-facilitated segmentation as tripartite structures corresponding to the nucleoplasmic ring, inner ring with central transport channel, and cytoplasmic ring, as confirmed by immunostaining. We demonstrate a range of NPC diameters with a bias for dilated NPCs at the basal nuclear surface, often in local clusters. These diameter biases are eliminated by disrupting linker of nucleoskeleton and cytoskeleton (LINC) complex-dependent connections between the nuclear envelope (NE) and the cytoskeleton, supporting that they reflect local variations in NE tension. Pan-ExM further reveals that the transmembrane nucleoporin/nup POM121 resides specifically at the nuclear ring in multiple model cell lines, surprising given the expectation that it would be a component of the inner ring like other transmembrane nups. Remarkably, however, POM121 shifts from the nuclear ring to the inner ring specifically in aged induced pluripotent stem cell derived neurons (iPSNs) from a patient withC9orf72amyotrophic lateral sclerosis (ALS). Thus, Pan-ExM allows the visualization of changes in NPC architecture that may underlie early steps in an ALS pathomechanism. Taken together, Pan-ExM is a powerful and accessible tool to visualize NPC plasticity in physiological and pathological contexts at single NPC resolution.
Central Presynapses Regulate Spontaneous Synaptic Vesicle Exocytosis Rate by Constraining Recycling Pool Density
Authors: Wilson P. , Kim N. , Cotter R. , Parkes M. , Reed M.N. , Gramlich M.W.
Published: September 2024

Synapses represent a fundamental unit of information transfer during cognition. They accomplish this via presynaptic vesicle exocytosis, which can occur either spontaneously or by an action potential leading to evoked release. It has been well established that evoked release is probabilistic in nature, but it has been less clear what mechanisms mediate spontaneous release. Understanding spontaneous release is important because it is an essential maintenance mechanism for synaptic connections. We propose a mechanistic framework and model of spontaneous release based on immobile vesicles in the reserve pool geometrically constraining mobile vesicles in the recycling pool, which provides a force leading to a spontaneous release rate. We experimentally support this framework using a combination of Scanning Electron Microscopy (SEM), high-resolution fluorescence microscopy techniques using pHluorin-VGlut1 and a single vesicle SGC5 reporter, and a computational model. We observe that the spontaneous release rate increases linearly with the number of vesicles but is constant in the absence of presynaptic actin. We then use an acute agent, Forskolin, to further constrain the volume of the recycling pool, leading to an increased spontaneous release rate. We show that our framework predicts the increasing spontaneous release rate experimentally observed. These results suggest that synapses constrain the density of the recycling pool to mediate spontaneous release rate via the entropic force.
Floral Reversion based micropropagation of Day-NeutralCannabis sativaL
Authors: Tabatabaei Darya Sadat , Abiri Rambod , Jones A.M.P.
Published: September 2024

Micropropagation systems have been developed for photoperiod sensitive cultivars of cannabis, but there are currently no published methods for day-neutral genotypes. Most established cannabis micropropagation systems rely on shoot proliferation using modal explants that need them to be maintained in vegetative growth, which is not possible for day-neutral genotypes. Floral reversion, the process by which plants revert to vegetative growth from the generative stage, has been demonstrated as an alternative and potentially more efficient approach to the micropropagation of photoperiodic cannabis. The current study investigated if this process could be adapted to facilitate the micropropagation of day-neutral genotypes and overcome existing barriers. During the process, various factors such as photoperiod and light intensity may influence the efficiency of floral reversion. To evaluate this approach in day-neutral cultivars, various photoperiods were compared to assess the impact on reversion rate and subsequent growth. Excised florets obtained fromin vitroday-neutralC. sativacv. “Blue Auto Mazar x auto Blueberry” seedlings were subjected to five photoperiods including 12.0, 16.0, 18.0, 20.0, and 24.0 hours of light per day for four weeks. Reversion rates and time, shoot length, shoot number, and node number were measured. Statistical analyses revealed significant differences (p-values < 0.05) in terms of reversion time among photoperiod treatments. The highest reversion rate happened under the 16.0 hr photoperiod with 72% success. The highest shoot lengths were observed under 20.0 hr of photoperiods with a mean of 10.1 mm and the lowest shoot length belonged to 12.0 hr of photoperiods with a mean of 5.6 mm, respectively. Reverted shoots developed vegetatively for some time before initiating new flowers. However, during this period the shoots were successfully rooted in vitro and then acclimated to the growth chamber where they completed their life cycle, including seed production. This process was also successfully achieved from a 2-year old culture ofC. sativacv. “Blue Auto Mazar”, demonstrating that it is feasible to use this approach for long term culture maintenance and multiplication. This study demonstrates that floral reversion can successfully be used to clonally propagate day-neutral cannabis plants and serves as a basis for developing large-scale clonal propagation and breeding strategies.
Mineral fertilization reduces the drought resistance of soil multifunctionality in a mountain grassland system through plant-soil interactions
Authors: Piton Gabin , Foulquier Arnaud , Bernard Lionel , Bonin Aurélie , Pommier Thomas , Lavorel Sandra , Geremia Roberto , Clement Jean Christophe
Published: September 2024

Abstract

Increasing droughts threaten soil microbial communities and the multiple functions they control in agricultural soils. These soils are often fertilized with mineral nutrients, but it remains unclear how this fertilization may alter the capacity of soil multifunctionality (SMF) to be maintained under drought, and how plant-soil interactions shape these effects. In this study, we used a mountain grassland soil to test the interactive effect of mineral nutrient (Nitrogen and Phosphorous) addition and drought on SMF with and without plants (Lolium perenne) in a mesocosm experiment. We calculated SMF based on 8 microbial properties associated with the capacity of soil microbes to store carbon (C), nitrogen (N) and phosphorous (P) in their biomass, and to process these elements through organic matter depolymerization, mineralization, nitrification and denitrification processes. To investigate mechanisms underlying the SMF response we characterized the associated changes in soil stoichiometry and microbial community composition using 16S and 18S rRNA amplicon sequencing. Our results showed that fertilization decreased the SMF drought resistance when plants were present, but the opposite was observed in the unplanted mountain grassland soil. Our analysis suggested this was due to the interaction of plants, fertilization and drought in influencing four coupled properties related to high SMF: high soil moisture, low microbial C limitation, high bacterial diversity and low bacteria gram positive:gram negative ratio. Altogether, our results suggested that reducing the use of mineral fertilizer for plant production in mountain grassland could improve the ability of their soils to maintain their multifunctionality during drought period. Finally, our study clearly further demonstrated the importance of plant in the complex responses of SMF to global changes and showed that combining stoichiometric and microbial diversity assessment represents a powerful approach to disentangle the underlying mechanisms.
Probing gluon GTMDs of the proton in deep inelastic diffractive dijet production at HERA
Authors: Linek Barbara , Łuszczak Marta , Schäfer Wolfgang , Szczurek Antoni
Published: September 2024

We calculate several differential distributions for diffractive dijets production in ep→e′jet jetp in the perturbative QCD dipole approach using off diagonal unintegrated gluon distributions (generalized transverse momentum dependent distributions, GTMDs). Different models from the literature are used. We concentrate on the contribution from exclusive qq¯ dijets. Results of our calculations are compared to H1 and ZEUS data, including specific experimental cuts in our calculations. In general, except for one GTMD, our results are below the HERA data. The considered mechanism is expected to gives a sizeable contribution to the ZEUS data, while it is negligible in the kinematics of the H1 measurement. This is in contrast to recent results from the literature where the normalization was adjusted to some selected distributions of the H1 collaboration and no agreement with other observables was checked. The ZEUS data provide stricter limitations on the GTMDs than the H1 data. We conclude, based on comparison to different observables, that the calculated cross sections are only a small fraction of the measured ones which contain probably also processes with pomeron remnant. Alternatively one could try to explain the experimental data by inclusion of qq¯g component of the photon wave function. We present also azimuthal correlations between the sum and the difference of dijet transverse momenta. The cuts on transverse momenta of jets generate corresponding azimuthal correlations that can be misidentified as due to elliptic gluon distributions.

Published by the American Physical Society
2024
Born-Oppenheimer potentials for
SU(3)
gauge theory
Authors: Alasiri Fareed , Braaten Eric , Mohapatra Abhishek
Published: September 2024

We develop parametrizations of eight of the lowest Born-Oppenheimer potentials for quarkonium hybrid mesons as functions of the separation r of the static quark and antiquark sources. The parameters are determined by fitting results calculated using pure SU(3) lattice gauge theory. The parametrizations have the correct limiting behavior at small r, where the potentials form multiplets associated with gluelumps. They have the correct limiting behavior at large r, where the potentials form multiplets associated with excitations of a relativistic string. There is a narrow avoided crossing in the small-r region between two potentials with the same Born-Oppenheimer quantum numbers.

Published by the American Physical Society
2024
Polarized dipole scattering amplitudes meet the valence quark model
Authors: Dumitru Adrian , Mäntysaari Heikki , Tawabutr Yossathorn
Published: September 2024

The recently revised small-x helicity evolution [], resumming the double-logarithmic factor, αsln2(1/x), allows for the study of helicity distributions of quarks and gluons at small Bjorken x, corresponding to high center-of-mass energy. In this work, we calculate the moderate-x initial conditions in the regime, αsln2(1/x)∼1, for the small-x helicity evolution using a light-front valence quark model of the proton, which provides additional physical information about the target. The perturbative emission and absorption of a gluon by the valence quarks are also included. The results, given in Eqs. (35), provide a new set of initial conditions with a significantly reduced number of free parameters than conventional models []. Consequently, the predictive power of small-x helicity evolution is expected to improve once the initial conditions from this work are incorporated.

Published by the American Physical Society
2024
Regurgitated dark matter
Authors: Kim TaeHun , Lu Philip , Marfatia Danny , Takhistov Volodymyr
Published: September 2024

We present a new paradigm for the production of the dark matter (DM) relic abundance based on the evaporation of early Universe primordial black holes (PBHs) themselves formed from DM particles. As a concrete realization, we consider a minimal model of the dark sector in which a first-order phase transition results in the formation of Fermiball remnants that collapse to PBHs, which then emit DM particles. We show that the regurgitated DM scenario allows for DM in the mass range ∼1–1016  GeV, thereby unlocking parameter space considered excluded.

Published by the American Physical Society
2024
Pressure-Tuned Quantum Criticality in the Locally Noncentrosymmetric Superconductor
CeRh2As2
Authors: Pfeiffer M. , Semeniuk K. , Landaeta J. F. , Borth R. , Geibel C. , Nicklas M. , Brando M. , Khim S. , Hassinger E.
Published: September 2024

The unconventional superconductor CeRh2As2 (critical temperature Tc≈0.4  K) displays an exceptionally rare magnetic-field-induced transition between two distinct superconducting (SC) phases, proposed to be states of even and odd parity of the SC order parameter, which are enabled by a locally noncentrosymmetric structure. The superconductivity is preceded by a phase transition of unknown origin at T0=0.5  K. Electronic low-temperature properties of CeRh2As2 show pronounced non-Fermi-liquid behavior, indicative of a proximity to a quantum critical point (QCP). The role of quantum fluctuations and normal state orders for the superconductivity in a system with staggered Rashba interaction is currently an open question, pertinent to explaining the occurrence of the two-phase superconductivity. In this work, using measurements of resistivity and specific heat under hydrostatic pressure, we show that the T0 order vanishes completely at a modest pressure of P0≈0.5  GPa, revealing a QCP. In line with the quantum criticality picture, the linear temperature dependence of the resistivity at

P

0

evolves into a Fermi-liquid quadratic dependence as quantum critical fluctuations are suppressed by increasing pressure. Furthermore, the domelike behavior of Tc around P0 implies that the fluctuations of the T0 order are involved in the SC pairing mechanism.

Published by the American Physical Society
2024
Competition between transient oscillations and early stochasticity in exponentially growing populations
Authors: Hein Yaïr , Jafarpour Farshid
Published: September 2024

It has been recently shown that the exponential growth rate of a population of bacterial cells starting from a single cell shows transient oscillations due to early synchronized bursts of division. These oscillations are enhanced by cell size regulation and contain information about single-cell growth statistics. Here, we report a phase transition in these oscillations as a function of growth rate variability. Below the transition point, these oscillations become asymptotically deterministic and can be measured experimentally, while above the transition point, the stochasticity in population growth dominates the oscillations and masks all the information about single cell growth statistics. The analytically calculated transition point, which roughly corresponds to 13% variability in single-cell growth rate, falls within physiologically relevant parameters. Additionally, we show that the oscillations can stochastically emerge even when the initial state contains multiple cells with out-of-phase division cycles. We show that the amplitude and phase of these oscillations are stochastic and vary across repeated measurements with the same initial conditions. We provide analytic expressions as well as numerical estimates for the typical oscillation amplitude and the number of generations before the amplitude falls below a given measurement threshold for in multiple growth conditions.

Published by the American Physical Society
2024
Subsymmetry protected topology in topological insulators and superconductors
Authors: Kang Myungjun , Lee Mingyu , Cheon Sangmo
Published: September 2024

Exploration of topology protected by a certain symmetry is central in condensed matter physics. A recent idea of subsymmetry protected (SSP) topology—remains of a broken symmetry can still protect specific topological boundary states—has been developed and demonstrated in a photonic system [], but not in topological superconductors. Here, we extend this idea further by applying subsymmetry protecting perturbation (SSPP) to one-dimensional topological insulating and superconducting systems using the Su-Schrieffer-Hegger (SSH) and Kitaev models. Using the tight-binding and low-energy effective theory, we show that the SSP boundary states retain topological properties while the SSPP results in the asymmetry of boundary states. For the SSH model, an SSP zero-energy edge state localized on one edge possesses quantized polarization. In contrast, the other edge state is perturbed to have nonzero energy, and its polarization is not quantized. For topological superconductors, SSP zero-energy Majorana boundary states for spinful Kitaev models emerge on only one edge, contrary to the conventional belief that Majorana fermions emerge at opposite edges. Our findings can be used as a platform to expand our understanding of topological materials as they broaden our understanding of the symmetry in a topological system and a method to engineer Majorana fermions.

Published by the American Physical Society
2024
Crystal structure and Hirshfeld surface analysis of (E)-N-(2-styrylphenyl)benzenesulfonamide
Authors: Albert A. M. Dharani , Nagaraj Achyuta , Somarathinam Kanagasabai , Vinayagam Pavunkumar , Arasambattu K. Mohanakrishnan , Kothandan Gugan
Published: September 2024

The crystal structure of the title compound C20H17NO2S features hydrogen-bonding and C—H...π interactions. Hirshfeld surface analysis revealed that H...H, C...H/H...C and O...H/H...O interactions make a major contribution to the crystal packing. Docking studies were carried out to determine the binding affinity and interaction profile of the title compound with EGFR kinase, a member of the ErbB family of receptor tyrosine kinases, which is crucial for processes such as cell proliferation and differentiation. The title compound shows a strong binding affinity with EGFR kinase, with the most favourable conformation having a binding energy of −8.27 kcal mol−1 and a predicted IC50 of 870.34 nM, indicating its potential as a promising candidate for targeted lung cancer therapy.
Δ-Bis[(S)-2-(4-isopropyl-4,5-dihydrooxazol-2-yl)phenolato-κ2
N,O
1](1,10-phenanthroline-κ2
N,N′)ruthenium(III) hexafluoridophosphate
Authors: Kelani Monsuru T. , Muller Alfred , Lammertsma Koop
Published: September 2024

The title compound, [Ru(C12H14NO2)2(C12H8N2)]PF6 crystallizes in the tetragonal Sohnke space group P41212. The two bidentate chiral salicyloxazoline ligands and the phenanthroline co-ligand coordinate to the central RuIII atom through N,O and N,N atom pairs to form bite angles of 89.76 (15) and 79.0 (2)°, respectively. The octahedral coordination of the bidentate ligands leads to a propeller-like shape, which induces metal-centered chirality onto the complex, with a right-handed (Δ) absolute configuration [the Flack parameter value is −0.003 (14)]. Both the complex cation and the disordered PF6
− counter-anion are located on twofold rotation axes. Apart from Coulombic forces, the crystal cohesion is ensured by non-classical C—H...O and C—H...F interactions.
Persuasion for protection: an analysis of online safety videos on YouTube
Authors: Huang Liuyu , Goh Dion Hoe-Lian , Yin Stella Xin
Published: September 2024

Purpose

Public service announcements (PSAs) have been shown to be effective instruments that raise awareness, educate society, and change behaviors and attitudes. Many governments and organizations have utilized PSAs on social media to promote online safety among children and youth. However, we have limited understanding of the range of topics that these PSAs address and how they present their content to audiences. This study provides an inventory of the types of online safety topics that current PSAs address and a catalogue of the types of persuasive features employed by PSAs.

Design/methodology/approach

A content analysis of 220 YouTube PSA videos on online safety was conducted. Various topics under the umbrella of online safety were identified. Guided by the prospect theory and exemplification theory, different persuasive features employed in the PSAs were sought.

Findings

The findings highlight that the primary focus of these PSAs is on online safety behaviors and general instructions on online hygiene. Interestingly, nearly half of the videos employ a neutral frame, while a significant portion provides no evidential support. Additionally, video length was associated with the number of views and likes it gathered but not with the number of comments.

Originality/value

The inventory of PSAs can help researchers, practitioners, and policymakers better understand the type of content being produced and disseminated online as well as identify topics that are either over or under-represented. Further, the catalogue of the types of persuasive features employed by PSAs would be helpful in guiding research, practice, and policymaking in the context of creating effective online safety videos.
How can a single spark kindle a Prairie fire? Diffusion process and mechanism of medical disruptive innovation
Authors: Lai Xiuping , Zhang Wenhong , Chen Silei
Published: September 2024

Purpose

Medical disruptive innovation is essential for deepening the reform of health-care system. The theory of general disruptive innovation assumes that innovations can diffuse by benefiting and attracting consumers through observed and objective relative advantages. Yet decision-makers for adoption in health-care settings are safety-sensitive professionals whose cognitions barriers about underperformance in focal attributes will impede further evaluation of innovation's ancillary performance. Existing studies do not answer the question of how such innovations can overcome safety barriers, find early adopters and grow to the early majority. The purpose of this study is to investigate the process, mechanism, and path of early diffusion of medical disruptive innovation.

Design/methodology/approach

The authors conduct a longitudinal case study of the diffusion of Enhanced Recovery After Surgery (ERAS) in China during 2011–2018.

Findings

The authors find that the diffusion process of medical disruptive innovations can be viewed as a cognitive evolutionary process that sequentially establishes conformity, differentiation and normalization. Cognition reframing of expert, meaning and benefit for professionals is its implicit mechanism. When adoption may trigger cognitive concerns, actors’ very early (dis)adoption is driven by a combination of structural position, innovation attributes and performance perceptions; central actors then play amplifier roles in the development from early adopters to the early majority.

Originality/value

This study proposes a process theoretical framework for the early diffusion of disruptive innovation. By dissecting the key processes and mechanisms from a cognitive perspective, the study offers theoretical contributions and practical insights into the diffusion of disruptive innovation in professional settings.
A bi-directional distance transformation for the elimination of near-singularity in boundary element method
Authors: Dong Yunqiao , Tan Zhengxu , Sun Hengbo , Yuan Fengwei
Published: September 2024

Purpose

In traditional methods, a one-directional distance transformation is employed to eliminate the near-singularity in the radial direction. However, when the projection point of the source point is near the boundary of the integral element, the near-singularity in the circumferential direction still exists, resulting in large errors in the numerical results. The purpose of this paper is to propose a bi-directional distance transformation for the elimination of near-singularities in two directions arising from the irregular integral element.

Design/methodology/approach

The sources of the circumferential near-singularity caused by irregular sub-triangular element are analyzed in this paper. A bi-directional distance transformation based on the (a, β) transformation is proposed to eliminate the near-singularities in the two directions. The (a, β) transformation is initially introduced to separate the integral variables and streamline the implementation of subsequent transformations. In the transformed (a, β) coordinate system, a new distance transformation applied in the circumferential direction is constructed.

Findings

With the proposed method, the radial and circumferential near-singularities are eliminated using two different distance transformations, respectively. Thus, accurate calculations of the nearly singular integrals can be achieved, irrespective of the shape of the integral element.

Originality/value

Numerical examples are presented to calculate the nearly singular integrals of different orders over both the linear integral element and the quadratic integral element. Comparative studies demonstrate that the proposed method significantly improves the accuracy of these calculations.
Processing the cost analysis and maximizing efficiency: a case study of Furqani Sugar Mill
Authors: Bhayo Siraj A. , Pathan Nimra Gul , Abbas Ghulam , Kumar Narandar , Ahmed Nazeer
Published: September 2024

Learning outcomes

After completion of the case study, the students will be able to define and compute equivalent units of production, apply management accounting procedures for manufacturing businesses (Furqani Sugar Mills), calculate product cost and track product cost flows and prepare process cost summary using the weighted average method. By studying this case, learners will gain insights into the challenges and financial complexities faced by a sugar mill and how strategic decisions and economic analysis can impact the sustainability and profitability of such businesses.

Case overview/synopsis

This case study explained the problem Mr Zoraiz, chief financial officer (CFO) of Furqani Sugar Mill, was facing. The problems started in the month of November 2020. Mill’s owner Mr Jabbar asked him for suggestions that employees should not be laid off. So he was analysing and estimating the cost of production when increasing production. He was focusing on cost reduction in process or increasing production, and utilization of resources efficiently and effectively. This case study focused on the market segment of the sugar industry for process costing. Furqani Sugar Mill, founded in 1992 in Pakistan (Company Document), had a noble mission to improve the lives of local peasants by producing sugar and molasses. Pakistan heavily relied on agribusiness, particularly sugar production, which contributed significantly to manufacturing. However, Furqani Sugar Mill faced a dire situation despite its vital role. During the sugarcane season, it struggled due to a shortage of raw materials, primarily sugarcane. Zoraiz, the CFO, grappled with running the mill below total capacity in recent years due to two significant issues: government-fixed sugar prices and limited sugarcane supply from local farmers. The high cost of sugarcane hindered Zoraiz’s desire to operate at total capacity. Zoraiz, Furqani’s CFO, must decide what he can do so that the mill can operate at its total capacity. The future of Furqani Sugar Mill hung in the balance as Zoraiz navigated complex financial decisions while striving to uphold the mill’s legacy and commitment to the local community.

Complexity academic level

This case study is suitable for teaching in several modules, notably managerial accounting and control systems, management accounting decision-making and cost and management accounting. Specifically, it covers performance management and process costing in management accounts. It is appropriate for teaching at the undergraduate and postgraduate levels.

Supplementary materials

Teaching notes are available for educators only.

Subject code

CSS 1: Accounting and finance.
An ecological perspective into the role of case-based instruction in developing EFL student-teachers’ agency
Authors: Haj Seyed Javadi Yasaman Sadat , Meihami Hussein
Published: September 2024

Purpose

Teacher agency plays a crucial role in teachers’ professionalism and makes them capable of acting powerfully in their teaching context. The purpose of this study was to explore the role of case-based instruction (CBI) on the agency development of EFL (English as a foreign language) student-teachers.

Design/methodology/approach

The study followed a descriptive narrative design and involved ten student-teachers in five CBI sessions. The data collected through different data sources, such as narratives, interviews, recorded sessions and focused groups, were analyzed using a deductive-inductive thematic analysis.

Findings

The results showed that CBI has a constructive role in developing the agency of EFL student-teachers. Active participation in CBI sessions helps teachers consider their future desires. The exploration of cases in CBI sessions helps them recall past experiences that led to the development of their agency. Brainstorming ideas in CBI sessions helps teachers consider their beliefs in decision-making and analyze their past experiences. In conclusion, CBI can help develop teacher professionalism and acknowledgment of the importance of teacher agency.

Originality/value

The research has addressed student-teachers’ agency development through an ecological perspective and CBI.
Unlocking service excellence: the hierarchical impact of high-performance human resource practices
Authors: Wang Chung-Jen
Published: September 2024

Purpose

Based on the ability–motivation–opportunity (AMO) model, this research aims to examine the hierarchical impact of high-performance human resource practices (HPHRPs) on the work practices and service performance of hospitality organizations.

Design/methodology/approach

Through an extensive analysis of time-lagged, multilevel and multisource data encompassing 721 employees and 153 stores across 17 restaurant brands in Taiwan, this study illuminated the hierarchical impact of HPHRPs in fostering a service-oriented environment.

Findings

This study reveals that HPHRPs have a direct positive effect on service performance. It also highlights an exclusive indirect positive impact, indicating that HPHRPs contribute to elevated service performance through the multilevel mediating effect of team engagement. A distinctive aspect of this study is that it identifies service climate as a critical multilevel moderator, strengthening the positive relationship between HPHRPs and team engagement. Additionally, service climate is found to be a key factor that amplifies the indirect multilevel positive effect HPHRPs have on service performance by reinforcing team engagement.

Practical implications

Strategically implementing robust HPHRPs, fostering a stimulating work environment and emphasizing team interaction can help hospitality organizations cultivate workplaces that deliver unparalleled guest experiences.

Originality/value

This study offers a strategic roadmap for the hospitality industry with a comprehensive multilevel HPHRPs framework that is customized to the specific needs of the workforce, and focused on fostering a service climate to maximize the positive outcomes of service excellence.
Key drivers of green innovation in family firms: a machine learning approach
Authors: Veiga Pedro Mota
Published: September 2024

Purpose

This study aims to find the key drivers of green innovation in family firms by examining firm characteristics and geographical factors. It seeks to develop a conceptual framework that explains how internal resources and external environments influence environmental innovation practices in these businesses.

Design/methodology/approach

Using machine learning (ML) methods, this study develops a predictive model for green innovation in family firms, drawing on data from 3,289 family businesses across 27 EU Member States and 12 additional countries. The study integrates the Resource-Based View (RBV) and Location Theory to analyze the impact of firm-level resources and geographical contexts on green innovation outcomes.

Findings

The results show that both firm-specific resources, such as size, digital capabilities, years of operation and geographical factors, like country location, significantly influence the likelihood of family firms engaging in environmental innovation. Larger, technologically advanced firms are more likely to adopt sustainable practices, and geographic location is crucial due to different regulatory environments and market conditions.

Research limitations/implications

The findings reinforce the RBV by showing the importance of firm-specific resources in driving green innovation and extend Location Theory by emphasizing the role of geographic factors. The study enriches the theoretical understanding of family businesses by showing how noneconomic goals, such as socioemotional wealth and legacy preservation, influence environmental innovation strategies.

Practical implications

Family firms can leverage these findings to enhance their green innovation efforts by investing in technology, fostering sustainability and recognizing the impact of geographic factors. Aligning innovation strategies with both economic and noneconomic goals can help family businesses improve market positioning, comply with regulations and maintain a strong family legacy.

Originality/value

This research contributes a new perspective by integrating the RBV and Location Theory to explore green innovation in family firms, highlighting the interplay between internal resources and external environments. It also shows the effectiveness of machine learning methods in predicting environmental innovation, providing deeper insights than traditional statistical techniques.