bluuebunny/crossref_metadata_2025 huggingface dataset:
Mechanism of ASF1 Inhibition by CDAN1
Authors: Sedor Samantha F. , Shao Sichen
Published: August 2024

Codanin-1 (CDAN1) is an essential and ubiquitous protein named after congenital dyserythropoietic anemia type I (CDA-I), an autosomal recessive disease that manifests from mutations in theCDAN1orCDIN1(CDAN1 interactingnuclease 1) gene. CDAN1 interacts with CDIN1 and the paralogous histone H3-H4 chaperones ASF1A (Anti-SilencingFunction 1A) and ASF1B, but its function remains unclear. Here, we biochemically and structurally analyze CDAN1 complexes. We find that CDAN1 dimerizes and assembles into cytosolic complexes with CDIN1 and multiple copies of ASF1A/B. Single-particle cryogenic electron microscopy (cryo-EM) structures of CDAN1 complexes identify interactions with ASF1 mediated by two CDAN1 B-domains commonly found in ASF1 binding partners and two helices that mimic histone H3 binding. We additionally observe that one CDAN1 can recruit two ASF1 molecules and that ASF1A and ASF1B have different requirements for CDAN1 engagement. Our findings explain how CDAN1 sequesters and inhibits the chaperone function of ASF1A/B and provide new molecular-level insights into this enigmatic complex.
Epigenetic heterogeneity shapes the transcriptional landscape of regional microglia
Authors: Margetts Alexander V. , Vilca Samara J. , Bourgain-Guglielmetti Florence , Tuesta Luis M.
Published: August 2024

Microglia, the innate immune cells in the central nervous system, exhibit distinct transcriptional profiles across brain regions that are important for facilitating their specialized function. There has been recent interest in identifying the epigenetic modifications associated with these distinct transcriptional profiles, as these may improve our understanding of the underlying mechanisms governing the functional specialization of microglia. One obstacle to achieving this goal is the large number of microglia required to obtain a genome-wide profile for a single histone modification. Given the cellular and regional heterogeneity of the brain, this would require pooling many samples which would impede biological applications that are limited by numbers of available animals. To overcome this obstacle, we have adapted a method of chromatin profiling known as Cleavage Under Targets and Tagmentation (CUT&Tag-Direct) to profile histone modifications associated with regional differences in gene expression throughout the brain reward system. Consistent with previous studies, we find that transcriptional profiles of microglia vary by brain region. However, here we report that these regional differences also exhibit transcriptional network signatures specific to each region. Additionally, we find that these region-dependent network signatures are associated with differential deposition of H3K27ac and H3K7me3, and while the H3K27me3 landscape is remarkably stable across brain regions, the H3K27ac landscape is most consistent with the anatomical location of microglia which explain their distinct transcriptional profiles. Altogether, these findings underscore the established role of H3K27me3 in cell fate determination and support the active role of H3K27ac in the dynamic regulation of microglial gene expression. In this study, we report a molecular and computational framework that can be applied to improve our understanding of the role of epigenetic regulation in microglia in both health and disease, using as few as 2,500 cells per histone mark.Figure 1.

Pipeline of tissue processing and data analysis for the characterization of the microglial transcriptome and epigenome on a regional scale.
Iso-Seq enables discovery of novel isoform variants in human retina at single cell resolution
Authors: Wang Luozixian , Urrutia-Cabrera Daniel , Hung Sandy Shen-Chi , Hewitt Alex W. , Lukowski Samuel W. , Foord Careen , Wang Peng-Yuan , Tilgner Hagen , Wong Raymond C.B.
Published: August 2024

Recent single cell transcriptomic profiling of the human retina provided important insights into the genetic signals in heterogeneous retinal cell populations that enable vision. However, conventional single cell RNAseq with 3’ short-read sequencing is not suitable to identify isoform variants. Here we utilized Iso-Seq with full-length sequencing to profile the human retina at single cell resolution for isoform discovery. We generated a retina transcriptome dataset consisting of 25,302 nuclei from three donor retina, and detected 49,710 known transcripts and 241,949 novel transcripts across major retinal cell types. We surveyed the use of alternative promoters to drive transcript variant expression, and showed that 1-8% of genes utilized multiple promoters across major retinal cell types. Also, our results enabled gene expression profiling of novel transcript variants for inherited retinal disease (IRD) genes, and identified differential usage of exon splicing in major retinal cell types. Altogether, we generated a human retina transcriptome dataset at single cell resolution with full-length sequencing. Our study highlighted the potential of Iso-Seq to map the isoform diversity in the human retina, providing an expanded view of the complex transcriptomic landscape in the retina.
Forecasting hotspots of grassland suitability under climate change for restoration
Authors: Rana Santosh Kumar , Lindstrom Jessica , Lehrer Melissa A. , Ahlering Marissa , Hamilton Jill
Published: August 2024

●

Local species-climate relationships are often considered in restoration management. However, as climate change disrupts species-climate relationships, identifying factors that influence habitat suitability now and into the future for individual species, functional groups, and communities will be increasingly important for restoration. This involves identifying hotspots of community suitability to target seed sourcing and restoration efforts.

●

Using ensemble species distribution modeling (eSDM), we analyzed 26 grassland species commonly used in restoration to identify bioclimatic variables influencing their distributions. We predicted habitat suitability under current and future (2050) climates and identified hotspots where diverse species and functional group suitability was greatest. These hotspots of habitat suitability were then overlaid with estimates of landscape connectivity and protected status to quantify potential suitability for restoration now and into the future.

●

Temperature and precipitation during warmer quarters largely influenced grassland species habitat suitability. Hotspots of grassland habitat suitability were identified in Minnesota, North Dakota, and South Dakota, with projected northward shifts under future climate scenarios. Overlaying these hotspots with estimates of landscape connectivity and protected status revealed limited connectivity and protection, highlighting regions to prioritize for restoration and conservation efforts.

●

Leveraging an understanding of species relationship with climate, this research emphasizes the importance of quantifying connectivity and protected status across aggregated hotspots of species suitability for conservation and restoration. Identifying these hotspots now and into the future can be used to prioritize regions for seed sourcing and restoration, ensuring long-term maintenance of functional ecosystems across grassland communities.
Automated Evaluation of Antibiotic Prescribing Guideline Concordance in Pediatric Sinusitis Clinical Notes
Authors: Weissenbacher Davy , Dutcher Lauren , Boustany Mickael , Cressman Leigh , O’Connor Karen , Hamilton Keith W. , Gerber Jeffrey , Grundmeier Robert , Gonzalez-Hernandez Graciela
Published: August 2024

Background

Ensuring antibiotics are prescribed only when necessary is crucial for maintaining their effectiveness and is a key focus of public health initiatives worldwide. In cases of sinusitis, among the most common reasons for antibiotic prescriptions in children, health-care providers must distinguish between bacterial and viral causes based on clinical signs and symptoms. However, due to the overlap between symptoms of acute sinusitis and viral upper respiratory infections, antibiotics are often over-prescribed.

Objectives

Currently, there are no electronic health record (EHR)-based methods, such as lab tests or ICD-10 codes, to retroactively assess the appropriateness of these prescriptions, making manual chart reviews the only available method for evaluation, which is time-intensive and not feasible at a large scale. In this study, we propose using natural language processing to automate this assessment.

Methods

We developed, trained, and evaluated generative models to classify the appropriateness of antibiotic prescriptions in 300 clinical notes from pediatric patients with sinusitis seen at a primary care practice in the Children’s Hospital of Philadelphia network. We utilized standard prompt engineering techniques, including few-shot learning and chain-of-thought prompting, to refine an initial prompt. Additionally, we employed Parameter-Efficient Fine-Tuning to train a medium-sized generative model Llama 3 70B-instruct.

Results

While parameter-efficient fine-tuning did not enhance performance, the combination of few-shot learning and chain-of-thought prompting proved beneficial. Our best results were achieved using the largest generative model publicly available to date, the Llama 3.1 405B-instruct. On our test set, the model correctly identified 91.4% of the 35 notes where antibiotic prescription was appropriate and 71.4% of the 14 notes where it was not appropriate. However, notes that were insufficiently, vaguely, or ambiguously documented by physicians posed a challenge to our model, as none evaluation sets were accurately classified.

Conclusion

Our generative model demonstrated strong performance in the challenging task of chart review. This level of performance may be sufficient for deploying the model within the EHR, where it can assist physicians in real-time to prescribe antibiotics in concordance with the guidelines, or for monitoring antibiotic stewardship on a large scale.
The open to closed D-loop conformational switch determines length in filopodia-like actin bundles
Authors: Gadsby Jonathan R , Ioannou Pantelis Savvas , Butler Richard , Mason Julia , Smith Alison , Dobramysl Ulrich , Chin Stacey , Dobson Claire , Gallop Jennifer L
Published: August 2024

Filopodia, microspikes and cytonemes are implicated in sensing the environment and in dissemination of morphogens, organelles and pathogens across tissues. Their major structural component is parallel bundles of actin filaments that assemble from the cell membrane. Whilst the length of filopodia is central to their function, it is not known how their lengths are determined by actin bundle dynamics. Here, we identified a set of monoclonal antibodies that lengthen filopodia-like structures formed in a cell-free reconstitution system, and used them to uncover a key molecular switch governing length regulation. Using immunolabelling, enzyme-linked immunosorbent assays, immunoprecipitation and immunoblock experiments, we identified four antibodies that lengthen actin bundles by selectively binding the open DNase 1-binding loop (D-loop) of actin filaments. The antibodies inhibit actin disassembly and their effects can be alleviated by providing additional actin or cofilin. This work indicates that maintaining an open state of the actin filament D-loop is a mechanism of generating the long projections of filopodia-like actin bundles.
The Performance and Potential of Deep Learning for Predicting Species Distributions
Authors: Kellenberger Benjamin , Winner Kevin , Jetz Walter
Published: August 2024

Species distribution models (SDMs) address the whereabouts of species and are central to ecology. Deep learning (DL) is poised to further elevate the already significant role of SDMs in ecology and conservation, but the potential and limitations of this transformation are still largely unassessed.

We evaluate DL SDMs for 2,299 terrestrial vertebrate and invertebrate species at continental scale and 1km resolution in a like-for-like comparison with latest implementation of classic SDMs. We compare two DL methods (a multi-layer perceptron (MLP) on point covariates and a convolutional neural network (CNN) on geospatial patches) against existing SDMs (Maxent and Random Forest). On average, DL models match, but do not surpass, the performance of existing methods. DL performance is substantially weaker for species with narrow geographic ranges, fewer data points, and those assessed as threatened and hence often of greatest conservation concern. Furthermore, information leakage across dataset splits substantially inflates performance metrics, especially of CNNs. We find current DL SDMs to not provide significant gains, instead requiring careful experimental design to avoid biases. However, future advances in DL-supported use of ancillary ecological information have the potential to make DL a viable instrument in the larger SDM toolbox. Realising this opportunity will require a close collaboration between ecology and machine learning disciplines.
The Chinese longsnout catfish genome provides novel insights into the feeding preference and corresponding metabolic strategy of carnivores
Authors: Liu Yulong , Zhai Gang , Su Jingzhi , Gong Yulong , Yang Bingyuan , Lu Qisheng , Xi Longwei , Zheng Yutong , Cao Jingyue , Liu Haokun , Jin Junyan , Zhang Zhimin , Yang Yunxia , Zhu Xiaoming , Wang Zhongwei , Gong Gaorui , Mei Jie , Yin Zhan , Gozlan Rodolphe E. , Xie Shouqi , Han Dong
Published: August 2024

Fish show variation in feeding habits to adapt to complex environments. However, the genetic basis of feeding preference and the corresponding metabolic strategies that differentiate feeding habits remain elusive. Here, by comparing the whole genome of a typical carnivorous fish (Leiocassis longirostrisGünther) with that of herbivorous fish, we identify 250 genes through both positive selection and rapid evolution, including taste receptortaste receptor type 1 member 3(tas1r3) andtrypsin. We demonstrate thattas1r3is required for carnivore preference intas1r3-deficient zebrafish and in a diet-shifted grass carp model. We confirm that trypsin correlates with the metabolic strategies of fish with distinct feeding habits. Furthermore, marked alterations in trypsin activity and metabolic profiles are accompanied by a transition of feeding preference intas1r3-deficient zebrafish and diet-shifted grass carp. Our results reveal a conserved adaptation between feeding preference and corresponding metabolic strategies in fish, and provide novel insights into the adaptation of feeding habits over the evolution course.
Lorentzian quantum wells in graphene: The role of shape invariance in zero-energy-state trapping
Authors: Correa Francisco , Inzunza Luis , Jakubský Vít
Published: August 2024

Confining Dirac fermions in graphene using electrostatic fields is a challenging task. Electric quantum dots created by a scanning tunneling microscope tip can trap zero-energy quasiparticles. The Lorentzian quantum well provides a faithful, exactly solvable approximation for such a potential, hosting zero-energy bound states for certain values of the coupling constant. We show that in this critical configuration, the system can be related to the free-particle model by means of a supersymmetric transformation. The revealed shape invariance of the model greatly simplifies the calculation of the zero modes and naturally explains the degeneracy of the zero energy.

Published by the American Physical Society
2024
One-dimensional
Z4
topological superconductor
Authors: Tymczyszyn Max , McCann Edward
Published: August 2024

We describe the mean-field model of a one-dimensional topological superconductor with two orbitals per unit cell. Time-reversal symmetry is absent, but a nonsymmorphic symmetry, involving a translation by a fraction of the unit cell, mimics the role of time-reversal symmetry. As a result, the topological superconductor has Z4 topological phases, two that support Majorana bound states and two that do not, in agreement with a prediction based on K-theory classification [K. Shiozaki, M. Sato, and K. Gomi, ]. As with the Kitaev chain, the presence of Majorana bound states gives rise to the 4π-periodic Josephson effect. A random matrix with nonsymmorphic time-reversal symmetry may be block diagonalized, and every individual block has time-reversal symmetry described by one of the Gaussian orthogonal, unitary, or symplectic ensembles. We show how this is manifested in the energy level statistics of a random system in the Z4 class as the spatial period of the nonsymmorphic symmetry is varied from much less than to of the order of the system size.

Published by the American Physical Society
2024
No bulk thermal currents in massive Dirac fermions
Authors: Liu Feng , Dumitriu-I. A. Daria , Principi Alessandro
Published: August 2024

We calculate the energy current flowing in the bulk of a (2+1)-dimensional system of massive Dirac fermions and along a (1+1)-dimensional domain wall generated by flipping the sign of the particle mass. We show that, at low temperatures and in the long-wavelength limit, the system does not support a bulk thermal Hall current proportional to the temperature gradient. The only such contribution is due to states localized at the domain wall. This puts an end to a controversy existing in the literature and amends previous results obtained via first-order perturbation calculations.

Published by the American Physical Society
2024
Probing
CPV
mixing in the Higgs sector in vector boson fusion at a 1 TeV ILC
Authors: Vukašinović N. , Božović-Jelisavčić I. , Kačarević G. , Smiljanić I. , Vidaković I.
Published: August 2024

With the current precision of measurements by the ATLAS and CMS experiments, it cannot be excluded that a standard model (SM)-like Higgs boson is a CP violating mixture of CP-even and CP-odd states. We explore this possibility here, assuming Higgs boson production in ZZ-fusion, at 1 TeV ILC, with unpolarized beams. The full simulation of SM background and fast simulation of the signal is performed, simulating 8  ab−1 of data collected with the ILD detector. We demonstrate that the CP mixing angle ΨCP between scalar and pseudoscalar states can be measured with the statistical uncertainty of 3.8 mrad at 68% CL, corresponding to 1.44×10−5 for the

C

P

parameter fCP, for the pure scalar state. This is the first result on sensitivity of an e+e− collider to measure fCP in the Higgs production vertex in vector boson fusion.

Published by the American Physical Society
2024
Structure of
ccc¯c¯
tetraquarks and interpretation of LHC states
Authors: Anwar Muhammad Naeem , Burns Timothy J.
Published: August 2024

Motivated by recent experimental evidence for apparent ccc¯c¯ states by LHCb, CMS and ATLAS, we consider how the mass spectrum and decays of such states can be used to discriminate among their possible theoretical interpretations, with a particular focus on identifying whether quarks or diquarks are the most relevant degrees of freedom. Our preferred scenario is that X(6600) and its apparent partner state X(6400) are the tensor (2++) and scalar (0++) states of an S-wave multiplet of ccc¯c¯ states. Using tetraquark mass relations which are independent of (or only weakly dependent on) model parameters, we give predictions for the masses of additional partner states with axial and scalar quantum numbers. Additionally, we give predictions for relations among decay branching fractions to J/ψJ/ψ, J/ψηc, ηcηc, and D(*)D¯(*) channels. The scenario we consider is consistent with existing experimental data on J/ψJ/ψ, and our predictions for partner states and their decays can be confronted with future experimental data, to discriminate between quark and diquark models.

Published by the American Physical Society
2024
Gravitational waves from high-power twisted light
Authors: Atonga Eduard , Martineau Killian , Aboushelbaya Ramy , Barrau Aurélien , von der Leyen Marko , Howard Sunny , James Abigail , Lee Jordan , Lin Chunshan , Martin Heath , Ouatu Iustin , Paddock Robert , Ruskov Rusko , Timmis Robin , Norreys Peter
Published: August 2024

Recent advances in high-energy and high-peak-power laser systems have opened up new possibilities for fundamental physics research. In this work, the potential of twisted light for the generation of gravitational waves in the high frequency regime is explored for the first time. Focusing on Bessel beams, novel analytic expressions and numerical computations for the generated metric perturbations and associated powers are presented. The gravitational peak intensity is shown to reach 1.44×10−5  W m−2 close to the source, and 1.01×10−19  W m−2 ten meters away. Compelling evidence is provided that the properties of the generated gravitational waves, such as frequency, polarization states, and direction of emission, are controllable by the laser pulse parameters and optical arrangements.

Published by the American Physical Society
2024
Correlation functions of boundary and defect conformal field theories
Authors: Park Chanyong
Published: August 2024

Applying the holographic method, we investigate correlation functions of boundary and defect conformal field theories. To describe boundary conformal field theory, we consider an end of the world brane in an asymptotic AdS space, which behaves as a boundary in the dual conformal field theory. In this holographic setup, we calculate correlation functions involving the reflection effect at the boundary. We show that, when the end of the world brane has no degrees of freedom, the holographic calculation reproduces the correlation functions known in the boundary conformal field theory. When the boundary has nontrivial boundary entropy, we calculate one- and two-point functions nontrivially relying on the boundary entropy. We further study correlation functions of defect conformal field theory after introducing a p brane. We directly derive a bulk-to-defect two-point function without introducing an image operator and determine the coefficient of the two-point function exactly in the holographic setup.

Published by the American Physical Society
2024
Entanglement entropy via double-cone regularization
Authors: Kawamoto Taishi , Suzuki Yu-ki
Published: August 2024

This paper proposes an alternative regularization method for handling the ultraviolet behavior of entanglement entropy. Utilizing an iε prescription in the Euclidean double cone geometry, it accurately reproduces the universal behavior of entanglement entropy. The method is demonstrated in the free boson theory in arbitrary dimensions and two-dimensional conformal field theories. The findings highlight the effectiveness of the iε regularization method in addressing ultraviolet issues in quantum field theory and gravity, suggesting potential applications to other calculable quantities.

Published by the American Physical Society
2024
Runaway Gravitational Production of Dark Photons
Authors: Capanelli Christian , Jenks Leah , Kolb Edward W. , McDonough Evan
Published: August 2024

We demonstrate that gravitational particle production of a massive, Abelian, vector (Proca) field during inflation in the presence of nonminimal coupling to gravity may suffer from an instability which leads to runaway production of high-momentum modes. This is untenable unless there is some mechanism to regulate the runaway. We discuss the parameter space of the particle mass and nonminimal couplings where such a runaway occurs and possible ways to tame the runaway. We find that there is no obvious way to resolve the runaway in a UV completion or with kinetic mixing to the standard model.

Published by the American Physical Society
2024
Antiskyrmions in Ferroelectric Barium Titanate
Authors: Gonçalves Mauro A. P. , Paściak Marek , Hlinka Jiří
Published: August 2024

Typical magnetic skyrmion is a string of inverted magnetization within a ferromagnet, protected by a sleeve of a vortexlike spin texture, such that its cross-section carries an integer topological charge. Some magnets form antiskyrmions, the antiparticle strings which carry an opposite topological charge. Here we demonstrate that topologically equivalent but purely electric antiskyrmion can exist in a ferroelectric material as well. In particular, our computer experiments reveal that the archetype ferroelectric, barium titanate, can host antiskyrmions at zero field. The polarization pattern around their cores reminds ring windings of decorative knots rather than the typical magnetic antiskyrmion texture. We show that the antiskyrmion of barium titanate has just 2–3 nm in diameter, a hexagonal cross section, and an exotic topological charge with doubled magnitude and opposite sign when compared to the standard skyrmion string.

Published by the American Physical Society
2024
Correlation of structural and magnetic properties of
RFeO3
(
R=Dy,Lu
)
Authors: Biswas Banani , Naumov Pavel , Motti Federico , Hautle Patrick , Bartkowiak Marek , Pomjakushina Ekaterina V. , Stuhr Uwe , Fuchs Dirk , Lippert Thomas , Schneider Christof W.
Published: August 2024

In orthoferrites the rare-earth (R) ion has a big impact on structural and magnetic properties; in particular, the ionic size influences the octahedral tilt and the R3+−Fe3+ interaction modifies properties like the spin reorientation. Growth-induced strain in thin films is another means to modify materials properties since the sign of strain affects the bond length and therefore directly the orbital interaction. Our study focuses on epitaxially grown (010)-oriented DyFeO3 and LuFeO3 thin films, thereby investigating the impact of compressive lattice strain on the magnetically active Dy3+ and magnetically inactive Lu3+ compared to uniaxially strained single-crystal DyFeO3. The DyFeO3 films exhibits a shift of more than 20 K in spin-reorientation temperatures, maintain the antiferromagnetic Γ4 phase of the Fe lattice below the spin reorientation, and show double-step hysteresis loops for both in-plane directions between 5 and 390 K. This is the signature of an Fe-spin-induced ferromagnetic Dy3+ lattice above the Néel temperature of the Dy. The observed shift in the film spin reorientation temperatures vs lattice strain is in good agreement with isostatic single-crystal neutron diffraction experiments with a rate of 2 K/kbar.

Published by the American Physical Society
2024
Controlling Majorana hybridization in magnetic chain-superconductor systems
Authors: Awoga Oladunjoye A. , Ioannidis Ioannis , Mishra Archana , Leijnse Martin , Trif Mircea , Posske Thore
Published: August 2024

We propose controlling the hybridization between Majorana zero modes at the ends of magnetic adatom chains on superconductors by an additional magnetic adatom deposited close by. By tuning the additional adatom's magnetization, position, and coupling to the superconductor, we can couple and decouple the Majorana modes, as well as control the ground-state parity. The scheme is independent of microscopic details in ferromagnetic and helical magnetic chains on superconductors, with and without spin-orbit coupling, which we show by studying their full microscopic models and their common low-energy description. Our results show that scanning tunneling microscopy and electron-spin-resonance techniques are promising tools for controlling the Majorana hybridization in magnetic adatoms-superconductor setups, providing a basis for Majorana parity measurements, fusion, and braiding techniques.

Published by the American Physical Society
2024
Development of an advanced in-line multilayer deposition system at Diamond Light Source
Authors: Wang Hongchang , Majhi Arindam , Tan Wai Jue , Singhapong Wadwan , Morawe Christian , Sawhney Kawal
Published: August 2024

A state-of-the-art multilayer deposition system with a 4200 mm-long linear substrate translator housed within an ultra-high vacuum chamber has been developed. This instrument is engineered to produce single and multilayer coatings, accommodating mirrors up to 2000 mm in length through the utilization of eight rectangular cathodes. To ensure the quality and reliability of the coatings, the system incorporates various diagnostic tools for in situ thickness uniformity and stress measurement. Furthermore, the system features an annealing process capable of heating up to 700°C within the load-lock chamber. The entire operation, including pump down, deposition and venting processes, is automated through user-friendly software. In addition, all essential log data, power of sputtering source, working pressure and motion positions are automatically stored for comprehensive data analysis. Preliminary commissioning results demonstrate excellent lateral film thickness uniformity, achieving 0.26% along the translation direction over 1500 mm in dynamic mode. The multilayer deposition system is poised for use in fabricating periodic, lateral-graded and depth-graded multilayers, specifically catering to the beamlines for diverse scientific applications at Diamond Light Source.
Binding structures of SERF1a with NT17-polyQ peptides of huntingtin exon 1 revealed by SEC-SWAXS, NMR and molecular simulation
Authors: Lin Tien-Chang , Shih Orion , Tsai Tien-Ying , Yeh Yi-Qi , Liao Kuei-Fen , Mansel Bradley W. , Shiu Ying-Jen , Chang Chi-Fon , Su An-Chung , Chen Yun-Ru , Jeng U-Ser
Published: August 2024

The aberrant fibrillization of huntingtin exon 1 (Httex1) characterized by an expanded polyglutamine (polyQ) tract is a defining feature of Huntington's disease, a neurodegenerative disorder. Recent investigations underscore the involvement of a small EDRK-rich factor 1a (SERF1a) in promoting Httex1 fibrillization through interactions with its N terminus. By establishing an integrated approach with size-exclusion-column-based small- and wide-angle X-ray scattering (SEC-SWAXS), NMR, and molecular simulations using Rosetta, the analysis here reveals a tight binding of two NT17 fragments of Httex1 (comprising the initial 17 amino acids at the N terminus) to the N-terminal region of SERF1a. In contrast, examination of the complex structure of SERF1a with a coiled NT17-polyQ peptide (33 amino acids in total) indicates sparse contacts of the NT17 and polyQ segments with the N-terminal side of SERF1a. Furthermore, the integrated SEC-SWAXS and molecular-simulation analysis suggests that the coiled NT17 segment can transform into a helical conformation when associated with a polyQ segment exhibiting high helical content. Intriguingly, NT17-polyQ peptides with enhanced secondary structures display diminished interactions with SERF1a. This insight into the conformation-dependent binding of NT17 provides clues to a catalytic association mechanism underlying SERF1a's facilitation of Httext1 fibrillization.
Dicarbonyl[10,10-dimethyl-5,15-bis(pentafluorophenyl)biladiene]ruthenium(II): discovery of the first ruthenium tetrapyrrole cis-dicarbonyl complex by X-ray and electron diffraction
Authors: Pham Trong-Nhan , Shirley Hunter , Merkelbach Johannes , Gurung Kshitij , Palatinus Lukáš , Yap Glenn P. A. , Rosenthal Joel
Published: August 2024

Dicarbonyl[10,10-dimethyl-5,15-bis(pentafluorophenyl)biladiene]ruthenium(II), [Ru(C33H16F10N4)(CO)2] or Ru(CO)2[DMBil1], is the first reported ruthenium(II) cis-dicarbonyl tetrapyrrole complex. The neutral complex sports two carbonyls and an oligotetrapyrrolic biladiene ligand. Notably, the biladiene adopts a coordination geometry that is well distorted from square planar and much more closely approximates a seesaw arrangement. Accordingly, Ru(CO)2[DMBil1] is not only the first ruthenium cis-dicarbonyl with a tetrapyrrole ligand, but also the first metal biladiene complex in which the tetrapyrrole does not adopt a (pseudo-)square-planar coordination geometry. Ru(CO)2[DMBil1] is weakly luminescent, displaying λem = 552 nm upon excitation at λex = 500 nm, supports two reversible 1 e− reductions at −1.45 and −1.73 V (versus Fc+/Fc), and has significant absorption features at 481 and 531 nm, suggesting suitability for photocatalytic and photosensitization applications. While the structure of Ru(CO)2[DMBil1] was initially determined by X-ray diffraction, a traditionally acceptable quality structure could not be obtained (despite multiple attempts) because of consistently poor crystal quality. An independent structure obtained from electron diffraction experiments corroborates the structure of this unusual biladiene complex.
Crystal structure of bis(β-alaninium) tetrabromidoplumbate
Authors: Tonoyan Gayane S. , Giester Gerald , Ghazaryan Vahram V. , Chilingaryan Ruben Yu. , Margaryan Arthur A. , Mkrtchyan Artak H. , Petrosyan Aram M.
Published: August 2024

The title compound, poly[bis(β-alaninium) [[dibromidoplumbate]-di-μ-dibromido]] {(C2H8NO2)2[PbBr4]}
n
or (β-AlaH)2PbBr4, crystallizes in the monoclinic space group P21/n. The (PbBr4)2− anion is located on a general position and has a two-dimensional polymeric structure. The Pb center is holodirected. The supramolecular network is mainly based on O—H...Br, N—H...Br and N—H...O hydrogen bonds.
Synthesis, crystal structure and Hirshfeld surface analysis of 1-[(1-octyl-1H-1,2,3-triazol-4-yl)methyl]-3-phenyl-1,2-dihydroquinoxalin-2(1H)-one
Authors: Abad Nadeem , Mague Joel T. , Kalonji Mubengayi Camille , Alsubari Abdulsalam , Essassi El Mokhtar , Ramli Youssef
Published: August 2024

In the title molecule, C25H29N5O, the dihydroquinoxaline unit is not quite planar (r.m.s. deviation = 0.030 Å) as there is a dihedral angle of 2.69 (3)° between the mean planes of the constituent rings and the molecule adopts a hairpin conformation. In the crystal, the polar portions of the molecules are associated through C—H...O and C—H...N hydrogen bonds and C—H...π(ring) and C=O...π(ring) interactions, forming thick layers parallel to the bc plane and with the n-octyl groups on the outside surfaces.
Puckering effects of 4-hydroxy-L-proline isomers on the conformation of ornithine-free Gramicidin S
Authors: Asano Akiko , Nakayama Kanako , Okada Sakura , Kato Takuma , Doi Mitsunobu
Published: August 2024

The cyclic peptide cyclo(Val-Leu-Leu-D-Phe-Pro)2 (peptide 1) was specifically designed for structural chemistry investigations, drawing inspiration from Gramicidin S (GS). Previous studies have shown that Pro residues within 1 adopt a down-puckering conformation of the pyrrolidine ring. By incorporating fluoride-Pro with 4-trans/cis-isomers into 1, an up-puckering conformation was successfully induced. In the current investigation, introducing hydroxyprolines with 4-trans/cis-isomer configurations (tHyp/cHyp) into 1 gave cyclo(Val-Leu-Leu-D-Phe-tHyp)2 methanol disolvate monohydrate, C62H94N10O12·2CH4O·H2O (4), and cyclo(Val-Leu-Leu-D-Phe-cHyp)2 monohydrate, C62H94N10O12·H2O (5), respectively. However, the puckering of 4 and 5 remained in the down conformation, regardless of the geometric position of the hydroxyl group. Although the backbone structure of 4 with trans-substitution was asymmetric, the asymmetric backbone of 5 with cis-substitution was unexpected. It is speculated that the anticipated influence of stress from the geometric positioning, which was expected to affect the puckering, may have been mitigated by interactions between the hydroxyl groups of hydroxyproline, the solvent molecules, and peptides.
Examining the integration of ERP and BI in the industrial sector and its impact on decision-making processes in KSA
Authors: Jaradat Zaid , AL-Hawamleh Ahmad , Hamdan Allam
Published: August 2024

Purpose

The Kingdom of Saudi Arabia’s dedicated pursuit of technological modernization positions it as a forefront leader in integrating advanced systems, aligning smoothly with the ambitious goals outlined in Vision 2030. The purpose of this study is to investigate the influence of integrating enterprise resource planning (ERP) and business intelligence (BI) systems on decision-making processes within the industrial sector of Saudi Arabia.

Design/methodology/approach

Using a quantitative research design, this study uses a bootstrapping approach and partial least squares structural equation modeling to meticulously analyze data collected from Saudi industrial firms.

Findings

The research reveals favorable relationships among infrastructure readiness, data quality, security and access control, user capabilities, user training and the integration of ERP and BI. These positive associations collectively affirm the overarching positive impact of ERP and BI integration on decision-making processes within the industrial sector.

Practical implications

The study underscores the strategic imperative of aligning organizational practices with the identified characteristics to fully unlock the potential benefits of ERP and BI integration in the Saudi Arabian industrial sector.

Originality/value

This study contributes significantly to the existing literature by delving into the integration of ERP and BI in the industrial sector and its nuanced impact on decision-making processes, specifically in the context of the Kingdom of Saudi Arabia – an area that has not been extensively studied.
Customer involvement in co-development: problem-solving and decision-making in new product development
Authors: Dean Tereza , Zhang Haisu , Xiao Yazhen
Published: August 2024

Purpose

Customers can participate in new product development (NPD) in many ways. Drawing on the knowledge-based view (KBV) and innovation literature, this study aims to contrast two main product development activity types, i.e. problem-solving and decision-making. It proposes customers play distinct roles if they get involved in these activities, which influence NPD outcomes differently. It also explores customer need specificity as a boundary condition for the above-mentioned relationships.

Design/methodology/approach

The authors collected survey data from 308 managers in the innovation domain.

Findings

Customer involvement in problem-solving and decision-making distinctively influences new product innovativeness and development speed. Customer need specificity interacts with the two co-development types differently to impact these NPD outcomes further.

Research limitations/implications

This research extends the KBV and addresses the inconsistent findings in the literature regarding customer involvement as co-developers in innovation. It also provides novel insights into how knowledge characteristics like customer need specificity can direct co-developing activities to generate distinct NPD results.

Practical implications

This paper offers practical implications for firms on how to involve customers in developing innovative new products while managing development speed.

Originality/value

Prior research has yet to distinguish customer responsibilities related to co-development activities. This research fills this gap and offers novel insights that problem-solving and decision-making have opposite impacts on different NPD outcomes. This research demonstrates that finer knowledge about customer involvement responsibilities is needed for critical NPD outcomes.
The nexus between CRM and behavioural loyalty in hotel sector: the mediating role of relationship quality (trust and satisfaction)
Authors: Karim Rashed Al , Rabiul Md Karim , Tahrin Sunehla , Arfat Sayed Mohammed
Published: August 2024

Purpose

This study aims to examine how hotel customer relationship management (CRM) practices affect tourist behavioural loyalty. This study also investigates the relationship quality (trust and satisfaction) as a mediator between CRM practices and tourist behavioural loyalty in Bangladesh’s hotel sector.

Design/methodology/approach

Data was collected through a survey using a standardized questionnaire that used a five-point Likert scale. A total of 411 respondents were selected using a convenient sampling method. The data was analysed and interpreted using Smart-PLS.

Findings

Relationship quality (both trust and satisfaction) partially mediates the relationship between hotel CRM practices and tourist behavioural loyalty in the hospitality industry.

Practical implications

The Bangladeshi hotel management can use the outcomes of this study to enhance tourist loyalty by implementing and maintaining better CRM features in the hotel.

Originality/value

The unique contribution to the hotel industry of Bangladesh is the role of relationship quality, which includes trust and customer satisfaction, as a mediator between hotel CRM practices and traveller behavioural loyalty.
Enhancing service delivery through digital transformation in the public sector in South Africa
Authors: Shibambu Amos , Ngoepe Mpho
Published: August 2024

Purpose

This study aims to explore how service delivery can be enhanced through digital transformation in the public sector in South Africa.

Design/methodology/approach

This case study used a qualitative research approach to obtain data through semi-structured interviews. The units of analysis were made up of individual professionals limited to purposive sampling to select chief information officers, investigators and administrative officers from national government departments and state-owned enterprises. The collected data from 12 participants was thematically analysed. The findings revealed that the government lacks legislation and strategy for digital transformation, leading to inconsistent implementation of digital transformation that enhances service delivery in the public sector of South Africa.

Findings

The findings revealed that the government lacks legislation and strategy for digital transformation, leading to inconsistent implementation of digital transformation that enhances service delivery in the public sector of South Africa.

Research limitations/implications

The study was limited to the public sector of South Africa; however, its recommendations are applicable to all organisations that need to provide their services using digital transformation.

Practical implications

Practically, the implications of this study will serve as a resourceful benchmark for the public sector and other organisations.

Social implications

Socially, the implications of this study ensure proper implementation of its recommendations to enhance service delivery in the public sector and other organisations.

Originality/value

Regarding the value that this study brings, it proposes an amendment of the current legislative framework in favour of one that covers digital transformation, which has become dominant in today’s enhanced provision of service delivery.
Digital financial literacy and usage of cashless payments in Jordan: the moderating role of gender
Authors: Shehadeh Maha , Dawood H.M. , Hussainey Khaled
Published: August 2024

Purpose

This study aims to examine the relationships between various components of digital financial literacy, namely, awareness, subjective knowledge, experience, the digital legal framework and skills, and their influence on the adoption of cashless payment systems among university affiliates in Jordan. It also explores the mediating role of gender in this relationship. The study integrates the Theory of Planned Behavior (TPB) and social role theory (SRT).

Design/methodology/approach

This study uses a cross-sectional survey across 34 Jordanian universities. Data from 418 participants were analyzed, focusing on factor analysis to assess the constructs' reliability and validity and to explore the moderating effects.

Findings

The findings illuminate that digital financial awareness, experience and skills are significant catalysts for using cashless payments among the targeted demographic. In contrast, the digital legal framework and subjective financial knowledge did not significantly influence cashless payment use. Additionally, gender differences emerged, highlighting a stronger association between digital financial experience and cashless payment usage for women.

Originality/value

The study's uniqueness stems from its detailed analysis of digital financial literacy's effect on cashless payment adoption in Jordan's academia, incorporating aspects like legal frameworks, awareness, and skills. It innovatively considers gender's moderating role, adding fresh insights into digital finance practices. Using the TPB and SRT, the research connects theory with Jordan's empirical data, suggesting strategies for education and policy. This work advances understanding of digital financial literacy in fostering a more inclusive digital financial system, contributing significantly to digital finance and behavioral economics literature.
An experimental investigation of environmental knowledge sharing in a supply chain coopetition situation
Authors: Dai Jing , Jin Yao “Henry” , Cantor David E. , Elking Isaac , Guntuka Laharish
Published: August 2024

Purpose

Despite the important role that suppliers have in enhancing the environmental performance of a buyer firm, previous research has not investigated the individual-level motivations of supplier employees (representatives) in supplier-to-supplier environmental knowledge sharing. Thus, we use insights from the coopetition literature to examine how buyer firms can encourage supplier-to-supplier environmental knowledge sharing with the aim of improving the buyer’s environmental performance.

Design/methodology/approach

We empirically test our model using an online vignette-based experiment administered to supply chain managers. We contextualized our results using insights from interviews with senior managers representing firms operating in a broad array of industries.

Findings

We find that a supplier representative’s personal environmental values influence their commitment to an environmental consortium with a rival firm, and they are subsequently willing to share proprietary environmental knowledge. In turn, these relationships are moderated by situational factors including competitive intensity and buyer power.

Originality/value

The study of coopetition is an emerging stream of research in operations management. Our findings improve the understanding on how a focal actor within a buyer–supplier coopetitive network can promote environmental knowledge sharing behavior.
What progress has resulted since the Safeguarding Adults Review concerning the deaths of Joanna, Jon and Ben?
Authors: Roach Heather
Published: August 2024

Purpose

The author, who is Chair of Norfolk’s Safeguarding Adults’ Board (SAB) reflects on the impact of a Safeguarding Adults Review (SAR) and the actions that resulted. The purpose of the paper is to provide an insight into a significant SAR and the resulting actions desinged to change practice.

Design/methodology/approach

The actions illuminate the power of hospitals and politicians over people’s lives. It took the deaths of three young adults with learning disabilities, in a hospital, to move beyond the status quo and organise some very different service responses.

Findings

“Progress summits” have considered local and national actions. There have been important gains and setbacks, including the delayed reform of the Mental Health Act. Despite uncertainties, SAB can be detonators to listening and taking action.

Originality/value

This is a unique insight into the impact of a Safeguarding Adults Review and the actions that resulted from this.