bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on the onset mechanism of bio-blister degradation of polyolefin by diatom attachment in seawater
Authors: Nakatani Hisayuki , Narizumi Shun , Okubo Seiya , Motokucho Suguru , Dao Anh Thi Ngoc , Kim Hee-Jin , Yagi Mitsuharu , Kyozuka Yusaku , Miura Shigenobu , Josyula Kanth V.
Published: February 2024

It is essential to develop a mechanism for lowering the molecular weight of polyolefins to achieve biodegradation in seawater. In this study, a polypropylene/polylactic acid blend sample was first subjected to photodegradation pretreatment, and it was confirmed that in pure water, the acid generated promotes the polypropylene degradation (autoxidation), while in alkaline seawater, the promotion was inhibited by a neutralization reaction. In the autoxidation of polyolefins in alkaline seawater, aqueous Cl− was also the inhibitor. However, we found that autoxidation could be initiated even in seawater by lowering the pH and using dissociation of ClOH (called blister degradation). The blister degradation mechanism enabled autoxidation, even in seawater, by taking advantage of the ability of diatoms to secrete transparent exopolymer particles (TEP) to prevent direct contact between the surface layer of polyolefins and alkaline seawater. We named blister degradation in seawater with diatoms as bio-blister degradation and confirmed its manifestation using linear low-density polyethylene (LLDPE)/starch samples by SEM, IR, DSC and GPC analysis.
Auditory stimulation during REM sleep modulates REM electrophysiology and cognitive performance
Authors: Navarrete Miguel , Greco Viviana , Rakowska Martyna , Bellesi Michele , Lewis Penelope A.
Published: February 2024

REM sleep is critical for memory, emotion, and cognition. Manipulating brain activity during REM could improve our understanding of its function and benefits. Earlier studies have suggested that auditory stimulation in REM might modulate REM time and reduce rapid eye movement density. Building on this, we studied the cognitive effects and electroencephalographic responses related to such stimulation. We used acoustic stimulation locked to eye movements during REM and compared two overnight conditions (stimulation and no-stimulation). We evaluated the impact of this stimulation on REM sleep duration and electrophysiology, as well as two REM-sensitive memory tasks: visual discrimination and mirror tracing. Our results show that this auditory stimulation in REM decreases the rapid eye movements that characterize REM sleep and improves performance on the visual task but is detrimental to the mirror tracing task. We also observed increased beta-band activity and decreased theta-band activity following stimulation. Interestingly, these spectral changes were associated with changes in behavioural performance. These results show that acoustic stimulation can modulate REM sleep and suggest that different memory processes underpin its divergent impacts on cognitive performance.
Akkermansia muciniphila-induced trained immune phenotype increases bacterial intracellular survival and attenuates inflammation
Authors: Peña-Cearra Ainize , Palacios Ainhoa , Pellon Aize , Castelo Janire , Pasco Samuel Tanner , Seoane Iratxe , Barriales Diego , Martin Jose Ezequiel , Pascual-Itoiz Miguel Ángel , Gonzalez-Lopez Monika , Martín-Ruiz Itziar , Macías-Cámara Nuria , Gutiez Naiara , Araujo-Aris Sarai , Aransay Ana Mª , Rodríguez Héctor , Anguita Juan , Abecia Leticia
Published: February 2024

The initial exposure to pathogens and commensals confers innate immune cells the capacity to respond distinctively upon a second stimulus. This training capacity might play key functions in developing an adequate innate immune response to the continuous exposure to bacteria. However, the mechanisms involved in induction of trained immunity by commensals remain mostly unexplored. A. muciniphila represents an attractive candidate to study the promotion of these long-term responses. Here, we show that priming of macrophages with live A. muciniphila enhances bacterial intracellular survival and decreases the release of pro- and anti-inflammatory signals, lowering the production of TNF and IL-10. Global transcriptional analysis of macrophages after a secondary exposure to the bacteria showed the transcriptional rearrangement underpinning the phenotype observed compared to acutely exposed cells, with the increased expression of genes related to phagocytic capacity and those involved in the metabolic adjustment conducing to innate immune training. Accordingly, key genes related to bacterial killing and pro-inflammatory pathways were downregulated. These data demonstrate the importance of specific bacterial members in the modulation of local long-term innate immune responses, broadening our knowledge of the association between gut microbiome commensals and trained immunity as well as the anti-inflammatory probiotic potential of A. muciniphila.
All paths lead to hubs in the spectroscopic networks of water isotopologues H216O and H218O
Authors: Tóbiás Roland , Diouf Meissa L. , Cozijn Frank M. J. , Ubachs Wim , Császár Attila G.
Published: February 2024

Network theory has fundamentally transformed our comprehension of complex systems, catalyzing significant advances across various domains of science and technology. In spectroscopic networks, hubs are the quantum states involved in the largest number of transitions. Here, utilizing network paths probed via precision metrology, absolute energies have been deduced, with at least 10-digit accuracy, for almost 200 hubs in the experimental spectroscopic networks of H216O and H218O. These hubs, lying on the ground vibrational states of both species and the bending fundamental of H216O, are involved in tens of thousands of observed transitions. Relying on the same hubs and other states, benchmark-quality line lists have been assembled, which supersede and improve, by three orders of magnitude, the accuracy of the massive amount of data reported in hundreds of papers dealing with Doppler-limited spectroscopy. Due to the omnipresence of water, these ultraprecise line lists could be applied to calibrate high-resolution spectra and serve ongoing and upcoming space missions.
Additive manufacturing of defect-free TiZrNbTa refractory high-entropy alloy with enhanced elastic isotropy via in-situ alloying of elemental powders
Authors: Mooraj Shahryar , Kim George , Fan Xuesong , Samuha Shmuel , Xie Yujun , Li Tianyi , Tiley Jaimie S. , Chen Yan , Yu Dunji , An Ke , Hosemann Peter , Liaw Peter K. , Chen Wei , Chen Wen
Published: February 2024

Laser powder-bed fusion (L-PBF) additive manufacturing presents ample opportunities to produce net-shape parts. The complex laser-powder interactions result in high cooling rates that often lead to unique microstructures and excellent mechanical properties. Refractory high-entropy alloys show great potential for high-temperature applications but are notoriously difficult to process by additive processes due to their sensitivity to cracking and defects, such as un-melted powders and keyholes. Here, we present a method based on a normalized model-based processing diagram to achieve a nearly defect-free TiZrNbTa alloy via in-situ alloying of elemental powders during L-PBF. Compared to its as-cast counterpart, the as-printed TiZrNbTa exhibits comparable mechanical properties but with enhanced elastic isotropy. This method has good potential for other refractory alloy systems based on in-situ alloying of elemental powders, thereby creating new opportunities to rapidly expand the collection of processable refractory materials via L-PBF.
Deeply subwavelength mid-infrared phase retardation with α-MoO3 flakes
Authors: Enders Michael T. , Sarkar Mitradeep , Giteau Maxime , Deeva Aleksandra , Herzig Sheinfux Hanan , Shokooh-Saremi Mehrdad , Koppens Frank H. L. , Papadakis Georgia T.
Published: February 2024

Phase retardation is a cornerstone of modern optics, yet, at mid-infrared (mid-IR) frequencies, it remains a major challenge due to the scarcity of simultaneously transparent and birefringent crystals. Most materials resonantly absorb due to lattice vibrations occurring at mid-IR frequencies, and natural birefringence is weak, calling for hundreds of microns to millimeters-thick phase retarders for sufficient polarization rotation. Here, we demonstrate mid-IR phase retardation with flakes of α-MoO3 that are more than ten times thinner than the operational wavelength, achieving 90 degrees polarization rotation within one micrometer of material. We report conversion ratios above 50% in reflection or transmission mode, and wavelength tunability by several micrometers. Our results showcase that exfoliated flakes of low-dimensional crystals can serve as a platform for mid-IR miniaturized integrated low-loss polarization control.
Cathodic protection mechanism of iron and steel in porous media
Authors: Martinelli-Orlando Federico , Mundra Shishir , Angst Ueli M.
Published: February 2024

Cathodic protection was introduced two centuries ago and since has found widespread application in protecting structures such as pipelines, offshore installations, and bridges from corrosion. Despite its extensive use, the fundamental working mechanism of cathodic protection remains debated, particularly for metals in porous media such as soil. Here, we use in-situ and ex-situ characterisation techniques coupled with electrochemical measurements to characterise the spatio-temporal changes occurring at the steel-electrolyte interface. We show that upon cathodic protection, the interfacial electrolyte undergoes alkalinisation and deoxygenation, and that depending on polarisation conditions, an iron oxide film can simultaneously form on the steel surface. We further demonstrate that these changes in interfacial electrolyte chemistry and steel surface state result in altered anodic and cathodic reactions and their kinetics. We propose a mechanism of cathodic protection that integrates previous theories, based on both concentration and activation polarisation, complimentarily. We discuss the implications of this study in enhancing corrosion protection technologies and the safe, economical, and environmentally friendly operation of critical steel-based infrastructures.
Generating Independent RDCs Using Paramagnetic Tags
Authors: Chen Jia-Liang , Su Xun-Cheng
Published: February 2024

A metal ion with magnetic anisotropy in a biomolecule exerts strong paramagnetic effects on the nucleus spins of biomolecules in the NMR spectrum. The paramagnetic effects including paramagnetic relaxation enhancement (PRE), pseudocontact shift (PCS) and residual dipolar coupling (RDC) are valuable structural and dynamic restraints of biomolecules, and generation of these paramagnetic effects is a prerequisite. The susceptibility of magnetic anisotropy plays a similar role in the alignment of biomolecules to the commonly used alignment media in an external magnetic field. We summarize the strategies available for generating RDCs in proteins by paramagnetic labeling, selection of paramagnetic ions, and the factors influencing the magnitude of RDCs.
NMR Experiments for Measuring RDCs in Biomolecules
Authors: Fitzkee N. C. , Yadav R. , Ying J.
Published: February 2024

The measurement of residual dipolar couplings (RDCs) in biomolecules requires accurate measurement of scalar couplings. Because RDCs are used to interpret protein structure and motions, high precision is required, and many NMR experiments have been developed to measure several major classes of couplings accurately. A broad range of experiments are available, each with particular considerations, such as the appropriate macromolecular size or the desired perdeuteration level. In this chapter, we describe the general concepts involved in RDC measurement, targeting researchers wishing to add RDCs to their experimental toolbox. After considering the experimental uncertainty in RDCs, we present two major classes of experiments: direct measurements based on peak positions and quantitative J measurements based on peak intensities. We discuss the strengths and weaknesses of each approach and highlight recent examples where they have been fruitfully used. For more advanced spectroscopists, we include a table of commonly used experiments, indexed by coupling type. Finally, we close by discussing future directions for RDC measurement and the utility of non-uniform sampling approaches.
Study of Biomolecular Structure and Dynamics with Xplor-NIH
Authors: Bermejo Guillermo A. , Schwieters Charles D.
Published: February 2024

This chapter describes the residual dipolar coupling (RDC) functionality of the Xplor-NIH software package, used to both analyse pre-existing biomolecular structures and drive the structure determination process itself. The effects of dynamics on the RDC data are considered, notably, in terms of multi-conformation structure ensembles. Examples are provided, including fragments of Python scripts and shell commands for use on Linux and macOS X platforms.
Strategies for converting turn-motif and cyclic peptides to small molecules for targeting protein–protein interactions
Authors: Hayward Deanne , Beekman Andrew M.
Published: February 2024

Peptides are great starting points for drug discovery, but challenges remain in converting that potential to approved drugs. We review strategies for moving peptide features to small molecules, enabling small molecule drug development expertise.
How space-charge behaviour at grain boundaries in electroceramic oxides is modified by two restricted equilibria
Authors: Usler A. L. , Ketter F. , De Souza R. A.
Published: February 2024

Through continuum simulations, the fundamental differences in grain-boundary properties in acceptor-doped SrTiO3 obtained from imaging and electrical measurements are elucidated.
Neutral 2-phenylbenzimidazole-based iridium(iii) complexes with picolinate ancillary ligand: tuning the emission properties by manipulating the substituent on the benzimidazole ring
Authors: Martínez-Vollbert Emiliano , Philouze Christian , Cavignac Théo , Latouche Camille , Loiseau Frédérique , Lanoë Pierre-Henri
Published: February 2024

A luminescence study with ab initio calculations that allow us to determine the lowest emitting excited state of a series of neutral Ir(iii) complexes with 2-phenylbenzimidazole cyclometallating ligand.
Synthesis of a zeolite@mesoporous silica composite to improve the low-frequency acoustic performance of a miniature loudspeaker system
Authors: Liu Kongxin , Zeng Yifei , Han Lu , Che Shunai
Published: February 2024

A simple surfactant-directed sol–gel to synthesize Z@MS with hierarchical pores, which can effectively improve the low-frequency acoustic performance of miniature loudspeakers as the filling material.
Surface charge transfer doping of narrow-bandgap Sn–Pb perovskites for high-performance tandem solar cells
Authors: Sun Qiang , Zhang Zhiguo , Yu Haixuan , Huang Junyi , Li Xiongjie , Dai Letian , Wang Qi , Shen Yan , Wang Mingkui
Published: February 2024

This study reports on the surface charge transfer doping of narrow-bandgap Sn/Pb binary metal perovskites with benzyl viologen. The as-fabricated all perovskite two-terminal tandem solar cell exhibits a power conversion efficiency of 26.33%.
Biomass@MOF nanohybrid materials for competitive drug adsorption: analysis by conventional macroscopic models and statistical physical models
Authors: Rivadeneira-Mendoza Bryan Fernando , Quiroz-Fernández Luis Santiago , da Silva Fausthon Fred , Luque Rafael , Balu Alina M. , Rodríguez-Díaz Joan Manuel
Published: February 2024

This study discloses the design of nanohybrid Biomass@MOF resulting from the functionalization of a hydrochar (HC) through hydrothermal treatment (HT) of corn cob residues and MIL-53(Al).
Differential biotransformation of micropollutants in conventional activated sludge and up-flow anaerobic sludge blanket processes
Authors: Martin M. , Wu Jingyi , Rich Stephanie L. , Richardson Ruth E. , Helbling Damian E.
Published: February 2024

We report differential micropollutant biotransformations in a conventional activated sludge (CAS) process and a pilot-scale up-flow anaerobic sludge blanket (UASB) process operating in parallel at the same wastewater treatment plant.
Reaction dynamics of the methoxy anion CH3O− with methyl iodide CH3I
Authors: Gstir Thomas , Sundelin David , Michaelsen Tim , Ayasli Atilay , Swaraj Dasarath , Judy Jerin , Zappa Fabio , Geppert Wolf , Wester Roland
Published: February 2024

Studying nucleophilic substitution reactions of the polyatomic methoxy anion allows us to narrow the gap to the large systems used in organic synthesis. Despite its complexity, we find predominantly direct dynamics at all studied collision energies.
Food-safe glycidyl-free chain extenders for polylactides
Authors: Elkholy Hazem M. , Abdelwahab Mohamed A. , Naveed Muhammad , Abdelaziz Khaled , Rabnawaz Muhammad
Published: February 2024

Glycidyl-based chain extenders are broadly used as processing aids to enhance the physical properties of polyesters, but glycidyl-containing compounds have severe toxicity concerns.
AMF-SporeChip provides new insights into arbuscular mycorrhizal fungal asymbiotic hyphal growth dynamics at the cellular level
Authors: Richter Felix , Calonne-Salmon Maryline , van der Heijden Marcel G. A. , Declerck Stéphane , Stanley Claire E.
Published: February 2024

A new microfluidic platform – the AMF-SporeChip – enables immobilisation of arbuscular mycorrhizal fungal spores and confrontation of asymbiotic hyphae with physical obstacles, allowing the identification of various exploration strategies.
Surface engineering of a 2D CuFe-LDH/MoS2 photocatalyst for improved hydrogen generation
Authors: Vennapoosa Chandra Shobha , Shelake Sandip Prabhakar , Jaksani Bhavya , Jamma Aparna , Moses Abraham B. , Sesha Sainath Annadanam V. , Ahmadipour Mohsen , Pal Ujjwal
Published: February 2024

Creating effective heterostructure photocatalysts with S-scheme-based charge-transfer dynamics enables efficient electron transfers, thereby enhancing visible-light-induced photocatalytic hydrogen production.
A high heat dissipation strategy based on a multi-scale porous hydrogel and heat sink exhibiting cooling capacity comparable to that of forced air convection but with zero energy consumption
Authors: Yan Kaifen , Zhang Weifeng , Feng Xue , Zhao Weiyun , Wu Lingling , Deng Yuan
Published: February 2024

A new composite heat sink (CHS) is designed based on a multi-scale porous hydrogel. Owing to the high heat transfer coefficient and zero energy consumption property, the CHS shows great potential in electronic device cooling field.
Application of tobramycin benzyl ether as an antibiotic adjuvant capable of sensitizing multidrug-resistant Gram-negative bacteria to rifampicin
Authors: Ramirez Danzel Marie , Dhiman Shiv , Mukherjee Ayan , Wimalasekara Ruwani , Schweizer Frank
Published: February 2024

The emergence of aminoglycoside resistance has prompted the development of amphiphilic aminoglycoside derivatives which target bacterial membranes.
Study of heavy atom influence on poly-halogenated compounds using DP4/MM-DP4+/DP4+: insights and trends
Authors: Passaglia Lucas , Zanardi María M. , Sarotti Ariel M.
Published: February 2024

An in-depth analysis of the heavy atom effect in NMR predictions is reported, focusing on its impact in DP4, MM-DP4+, and DP4+ formalisms.
Partial substitution with a significant effect: coexistence of a wide band gap and large birefringence in the oxychalcogenide AEGe2O4Se (AE = Sr and Ba)
Authors: Ran Mao-Yin , Zhou Sheng-Hua , Wei Wen-Bo , Wang A-Yang , Wu Xin-Tao , Lin Hua , Zhu Qi-Long
Published: February 2024

Two novel 2D oxychalcogenides, AEGe2O4Se (AE = Sr and Ba), were designed using a partial substitution strategy which exhibits the coexistence of a wide band gap (Eg > 3.1 eV) and a large birefringence (Δn > 0.2).
The global burden of plastics in oral health: prospects for circularity, sustainable materials development and practice
Authors: Ong Albert , Teo Jerald Y. Q. , Watts David C. , Silikas Nikolaos , Lim Jason Y. C. , Rosa Vinicius
Published: February 2024

Plastics in oral healthcare: innovations to move away from landfills to create value and sustainable care.
Breaking the plane: B5H5 is a three-dimensional structure
Authors: Hernández-Juárez Gerardo , Barroso Jorge , Vásquez-Espinal Alejandro , Ortíz-Chi Filiberto , Tiznado William , Murillo Fernando , Merino Gabriel
Published: February 2024

Contrary to prior assumptions, the global minimum structure of B5H5 is not quasi-planar but rather an asymmetrical three-dimensional form.
Discovery of novel reticular materials for carbon dioxide capture using GFlowNets
Authors: Cipcigan Flaviu , Booth Jonathan , Barros Ferreira Rodrigo Neumann , Ribeiro dos Santos Carine , Steiner Mathias
Published: February 2024

GFlowNets discover reticular materials with simulated CO2 working capacity outperforming all materials in CoRE2019.
Facile mechanochemical synthesis of MIL-53 and its isoreticular analogues with a glance at reaction reversibility
Authors: Salvador Fillipp Edvard , Tegudeer Zhuorigebatu , Locke Halie , Gao Wen-Yang
Published: February 2024

Mechanochemistry provides synthetic access to MIL-53 type materials and reveals the relationship between metal–ligand reversibility and crystallite size.
Highly effective solid solution towards high thermoelectric and mechanical performance in Bi–Sb–Te alloys via Trojan doping
Authors: Shi Yong-Cai , Yang Jianmin , Wang Yu , Li Zu-Gang , Zhong Tian-Yu , Ge Zhen-Hua , Feng Jing , He Jiaqing
Published: February 2024

We present a novel approach named Trojan doping, which utilizes NaBiS2 to increase the solubility of Na in p-type BST alloys. The ZT value and the hardness of the doped sample are 58% and 45% higher than those of the pristine sample, respectively.
Exploring C–C bond formation reactions for expanding azulene derivatives linked at the 2- and/or 6-positions
Authors: Mathey Pierre , Fernández Israel , Morin Jean-François
Published: February 2024

Different strategies for the synthesis of π-extended, azulene-containing polyaromatic hydrocarbons (PAHs) were investigated and the most efficient was used to prepare azulene-fused anthracene derivatives.
Multiple-cycle photochemical cascade reactions
Authors: Liang Dong , Zhou Quan-Quan , Xuan Jun
Published: February 2024

In this review, we summarize recent advancements in multiple-cycle photochemical cascade reactions with particulars emphasizing the catalytic activation modes and the types of reactions involved.
Resisting death by metal: metabolism and Cu/Zn homeostasis in bacteria
Authors: Sullivan Matthew J. , Terán Ignacio , Goh Kelvin G.K. , Ulett Glen C.
Published: February 2024

Metal ions such as zinc and copper play important roles in host–microbe interactions and their availability can drastically affect the survival of pathogenic bacteria in a host niche. Mechanisms of metal homeostasis protect bacteria from starvation, or intoxication, defined as when metals are limiting, or in excess, respectively. In this mini-review, we summarise current knowledge on the mechanisms of resistance to metal stress in bacteria, focussing specifically on the homeostasis of cellular copper and zinc. This includes a summary of the factors that subvert metal stress in bacteria, which are independent of metal efflux systems, and commentary on the role of small molecules and metabolic systems as important mediators of metal resistance.
A parsec-scale Galactic 3D dust map out to 1.25 kpc from the Sun
Authors: Edenhofer Gordian , Zucker Catherine , Frank Philipp , Saydjari Andrew K. , Speagle Joshua S. , Finkbeiner Douglas , Enßlin Torsten A.
Published: February 2024

Context. High-resolution 3D maps of interstellar dust are critical for probing the underlying physics shaping the structure of the interstellar medium, and for foreground correction of astrophysical observations affected by dust.

Aims. We aim to construct a new 3D map of the spatial distribution of interstellar dust extinction out to a distance of 1.25 kpc from the Sun.

Methods. We leveraged distance and extinction estimates to 54 million nearby stars derived from the Gaia BP/RP spectra. Using the stellar distance and extinction information, we inferred the spatial distribution of dust extinction. We modeled the logarithmic dust extinction with a Gaussian process in a spherical coordinate system via iterative charted refinement and a correlation kernel inferred in previous work. In total, our posterior has over 661 million degrees of freedom. We probed the posterior distribution using the variational inference method MGVI.

Results. Our 3D dust map has an angular resolution of up to 14′ (Nside = 256), and we achieve parsec-scale distance resolution, sampling the dust in 516 logarithmically spaced distance bins spanning 69 pc to 1250 pc. We generated 12 samples from the variational posterior of the 3D dust distribution and release the samples alongside the mean 3D dust map and its corresponding uncertainty.

Conclusions. Our map resolves the internal structure of hundreds of molecular clouds in the solar neighborhood and will be broadly useful for studies of star formation, Galactic structure, and young stellar populations. It is available for download in a variety of coordinate systems online and can also be queried via the publicly available dustmaps Python package.
Simulations of early structure formation: Properties of halos that host primordial star formation
Authors: Lenoble R. , Commerçon B. , Rosdahl J.
Published: February 2024

Context.Population III (pop III) stars were born in halos characterised by a pristine gas composition. In such a halo, once the gas density reachesnH ∼ 1 cm−3, molecular cooling leads to the collapse of the gas and the birth of pop III stars. Halo properties, such as the chemical abundances, mass, and angular momentum can affect the collapse of the gas, thereby leading to the pop III initial mass function (IMF) of star formation.

Aims.We want to study the properties of primordial halos and how halos that host early star formation differ from other types of halos. The aim of this study is to obtain a representative population of halos at a given redshift hosting a cold and massive gas cloud that enables the birth of the first stars.

Methods.We investigated the growth of primordial halos in a ΛCDM Universe in a large cosmological simulation. We used the hydrodynamic code RAMSESand the chemical solver KROMEto study halo formation with non-equilibrium thermochemistry. We then identified structures in the dark and baryonic matter fields, thereby linking the presence or absence of dense gas clouds to the mass and the physical properties of the hosting halos.

Results.In our simulations, the mass threshold for a halo for hosting a cold dense gas cloud is ≃7 × 105 M⊙and the threshold in the H2mass fraction is found to be ≃2 × 10−4. This is in agreement with previous works. We find that the halo history and accretion rate play a minor role. Here, we present halos with higher HD abundances, which are shown to be colder, as the temperature in the range between 102 − 104 cm−3depends on the HD abundance to a large extent. The higher fraction of HD is linked to the higher spin parameter that is seen for the dense gas.
Characterizing structure formation through instance segmentation
Authors: López-Cano Daniel , Stücker Jens , Pellejero Ibañez Marcos , Angulo Raúl E. , Franco-Barranco Daniel
Published: February 2024

Dark matter haloes form from small perturbations to the almost homogeneous density field of the early universe. Although it is known how large these initial perturbations must be to form haloes, it is rather poorly understood how to predict which particles will end up belonging to which halo. However, it is this process that determines the Lagrangian shape of proto-haloes and it is therefore essential to understand their mass, spin, and formation history. We present a machine learning framework to learn how the proto-halo regions of different haloes emerge from the initial density field. We developed one neural network to distinguish semantically which particles become part of any halo and a second neural network that groups these particles by halo membership into different instances. This instance segmentation is done through the Weinberger method, in which the network maps particles into a pseudo-space representation where different instances can easily be distinguished through a simple clustering algorithm. Our model reliably predicts the masses and Lagrangian shapes of haloes object by object, as well as other properties such as the halo-mass function. We find that our model extracts information close to optimally by comparing it to the degree of agreement between twoN-body simulations with slight differences in their initial conditions. We publish our model open source and suggest that it can be used to inform analytical methods of structure formation by studying the effect of systematic manipulations of the initial conditions.
Spectroscopy of heavy exotic mesons using lattice QCD static potentials and the Born-Oppenheimer approximation
Authors: Wagner Marc
Published: February 2024

I discuss the investigation of heavy exotic mesons using lattice QCD static potentials and the Born-Oppenheimer approximation. I summarize selected recent results for b¯b¯qq tetraquarks, for I = 0 bottomonium and for I = 1 bottomonium.
Review of physics program at J-PET
Authors: Czerwiński Eryk
Published: February 2024

The Jagiellonian - Positron Emission Tomograph (J-PET) is a multi purpose detector for tests of discrete symmetries and quantum entanglement of photons originating from the decay of positronium atoms. The research is per formed by measurement of angular correlations between photons from the an nihilations of the lightest leptonic bound system. The J-PET detector is the only device which enables determination of polarisation of photons from positronium annihilation together with estimation of positronium spin axis on the event-by-event basis. The novelty of the system is based on a usage of plastic scintil-lators as active detection material and trigger-less data acquisition system. The aim of two independent detection setups currently in use together with different annihilation chambers is to improve limits on C, CP and CPT symmetries and to search for the entanglement of photons originating from electron-positron annihilation. Additionally a precise measurement of ortho-positronium life time would allow to test of non-relativistic quantum electrodynamics and search for Mirror Matter.
Exotic Meson candidates in COMPASS data
Authors: Spülbeck David
Published: February 2024

Abstract. One of the prime goals of the COMPASS experiment at CERN is the study of the light meson spectrum, with a particular emphasis on the search for exotic states. The focus of this paper is on signals of the lightest hybrid can didate π1(1600) with spin-exotic quantum numbers JPC = 1−+ in several decay channels such as π−π+π−, rwπ−, ωπ−π0, π−π+π−η, and KSKSπ. In addition, we highlight new results for the K−π+π− final state, which indicate a supernumerary state with respect to the constituent quark model with JP = 0−.
ηc production within light-cone approach in pp and eA collisions
Authors: Babiarz Izabela , Schäfer Wolfgang , Szczurek Antoni
Published: February 2024

Abstract. The charmonium state ηc is a pseudoscalar meson (JPC = 0−+). We will review the proton-proton and electron-ion reactions, where ηc can be produced through the fusion of two virtual gluons in pp collision or one virtual photon-one real photon in eA collision. The main ingredient in our light-cone approach is the space-like transition form factor with dependence on two virtu-alities of the particles. The idea is to construct the form factor based on the wave function of the cc¯ state. The radial part of the wave function can be found by solving the Schrödinger equation. The transformation to the light-cone variable is performed using the Terentev prescription. We present the effects of the so-obtained form factors in the context of electron-ion collisions. Future facilities such as EIC or LHeC give the opportunity to probe the form factor dependence on the virtuality in e−A collisions. Our results indicate that the electron-ion colliders can be considered as an alternative and provide supplementary data to those obtained in e+e− colliders.
Light front approach to axial meson photon transition form factors: Probing the structure of χc1 (3872)
Authors: Schäfer Wolfgang , Babiarz Izabela , Szczurek Antoni
Published: February 2024

Abstract. We propose to study the structure of the enigmatic χc1(3872) axial vector meson through its γL*γ → χc1 (3872) transition form factor. We use our recently derived light-front wave function representation of the form factor for the lowest cc¯ Fock-state. We found that the reduced width of the state is well within the current experimental bound recently published by the Belle collaboration. This strongly suggests a crucial role of the cc¯ Fock-state in the photon-induced production. Our predictions for the Q2 dependence can be tested by future single tagged e+e− experiments, giving further insights into the short-distance structure of this meson.
The femtoscopy analysis of the p - Λ system obtained in heavy-ion collisions within the HADES experiment
Authors: Rathod Narendra
Published: February 2024

Abstract. The study investigates hyperons in dense matter, addressing the “hyperon puzzle" and its implications for neutron stars. Utilizing femtoscopy in Ag-Ag heavy-ion collisions at 1.58 AGeV within the HADES experiment, the analysis focuses on Λ (uds) strange quarks. By reconstructing Lambdas through Λ → π− + p decay, the study measures the p - Λ correlation function, revealing a distinct peak and providing valuable insights into strong interaction parameters. The initial exploration of the nucleon-hyperon (N-Y) femtoscopic correlation signal is presented, with a focus on the ongoing nature of the contribution as a work in progress.
Measurement of KN scattering below the KN mass threshold
Authors: Noumi Hiroyuki , Inoue Kentaro , Kawasaki Shingo , Aikawa Shuu , Ajimura Shuhei , Akaishi Takaya , Asano Hidemitsu , Beer George , Berucci Carolina , Bragadireau Mario , Buehler Paul Alois , Busso Luigi , Cargnelli Michael , Choi Seonho , Curceanu Catalina , Enomoto Shun , Fujioka Hiroyuki , Fujiwara Yuya , Fukuda Tomokazu , Guaraldo Carlo , Hashimoto Tadashi , Hayano Ryugo S. , Hiraiwa Toshihiko , Iio Masami , Iliescu Mihai , Ishiguro Yusuke , Ishimoto Shigeru , Ishikawa Takashi , Ithashi Kenta , Iwai Massaki , Iwasaki Masahiko , Kanno Koki , Kato Kazuma , kato Yuko , Kienle Paul , Komatsu Yusuke , Kou Hiroshi , Ma Yue , Marton Johann , Matsuda Yasuyuki , MIzoi Yutaka , Morra Ombretta , Murayama Rie , Nagae To-mofumi , Ohnishi Hiroaki , Okada Shinji , Omar Zhadyra , Outa Haruhiko , Piscicchia Kristian , Sada Yuta , Sakaguchi Atsushi , Sakuma Fuminori , Sato Masaharu , Scordo Alessadro , Sekimoto Michiko , Shi Hexi , Shirotori Kotaro , Sirghi Diana , Sirghi Florin , Suzuki Ken , Suzuki Shoji , Suzuki Takatoshi , Tanida Kiyoshi , Tatsuno Hideyuki , Tokiyasu Atsushi O. , Tokuda Makoto , Tomono Dai , Toyoda Akihisa , Tsukada Kyo , Vazquez-Doce Oton , Widmann Eberhard , Yamaga Takumi , Yamazaki Toshimitsu , Yim Heejoong , Zhang Qi , Zmeskal Johannes ,   [J-PARC E31 collaboration]
Published: February 2024

Abstract. We measured πE invariant mass spectra below and above the K¯N mass threshold in the K−d → NπE reaction in order to study the K¯N interaction and the Λ(1405) resonance. This reaction can be described by the two-step process: (i) K¯N1 → K¯N followed by (ii) K¯N2 → πΣ, where N1 and N2 are nucleons bound in the deuteron. We deduced the S -wave scattering amplitude of K¯N →K¯N in the framework of the K¯N πΣ coupled channel so as to reproduce the observed πΣ spectra in the I = 0 channel. We found a resonance pole at 1417.7-7.4+6.0 (fitting error)-1.0+1.1 (systematic error) - i[26.9-7.9+6.0 (fitting error)-2.0+1.7 (systematic error)]MeV/c2.
On the total chromatic number of the direct product of cycles and complete graphs
Authors: Castonguay Diane , de Figueiredo Celina M.H. , Kowada Luis A.B. , Patrão Caroline S.R. , Sasaki Diana , Valencia-Pabon Mario
Published: February 2024

Ak-total coloringof a graphGis an assignment ofkcolors to the elements (vertices and edges) ofGso that adjacent or incident elements have different colors. The total chromatic number is the smallest integerkfor whichGhas ak-total coloring. The well known Total Coloring Conjecture states that the total chromatic number of a graph is either Δ(G) + 1 (called Type 1) or Δ(G) + 2 (called Type 2), where Δ(G) is the maximum degree ofG. We consider the direct product of complete graphsKm×Kn. It is known that if at least one of the numbersmornis even, thenKm×Knis Type 1, except forK2×K2. We prove that the graphKm×Knis Type 1 when bothmandnare odd numbers, by using that the conformable condition is sufficient for the graphKm×Knto be Type 1 when bothmandnare large enough, and by constructing the target total colorings by using Hamiltonian decompositions and a specific color class, called guiding color. We additionally apply our technique to the direct productCm×Knof a cycle with a complete graph. Interestingly, we are able to find a Type 2 infinite familyCm×Kn, whenmis not a multiple of 3 andn= 2. We provide evidence to conjecture that all otherCm×Knare Type 1.
‘My appetite and mind would go’: Inuit perceptions of (im)mobility and wellbeing loss under climate change across Inuit Nunangat in the Canadian Arctic
Authors: Ayeb-Karlsson Sonja , Hoad Anna , Trueba Mei L.
Published: February 2024

The academic literature on personal experiences of climate-induced wellbeing erosion (often conceptualised as ‘non-economic losses and damages’) is still limited. This represents a serious climate policy gap that hinders support for marginalised people across the world including Indigenous People. Lately, we have seen a rapid growth in empirical studies exploring linkages between climate change and mental health among Indigenous Inuit in Canada. However, its association with human (im)mobility remains unexplored. This review article brings together the empirical evidence of Inuit experiences and perceptions of climate-related wellbeing loss and (im)mobility while providing climate policy with guidance for appropriate action. The systematic review investigates how Inuit in Arctic Canada felt that climatic changes impacted their (im)mobility and mental health while putting these feelings into a wider context of colonial violence, forced child removal, the residential schools, and other systematic human rights abuses. Twelve electronic databases (four specific to Arctic research) were searched for English and French, peer reviewed, qualitative studies published between 2000 and 2021. Fifteen selected articles were analysed using NVivo and thematic narrative analysis from a climate-violence-health nexus systems approach. Three overarching climate-related wellbeing loss themes, all strongly intertwined with feelings of immobility, emerged from the literature namely ‘identity and cultural loss’, ‘land connection as a source of healing’, and ‘changing environment triggering emotional distress’. The narratives circled around Inuit land connection and how climate-induced temporary (im)mobility interrupted this relationship. Climatic changes isolated Inuit away from the land and cut off their ability to partake in land activities. This strongly eroded Inuit wellbeing, expressed through distress, anxiety, depression, social tension, suicide ideation and deep feelings of cultural loss. The findings showed how Inuit mental health strongly depend on a sustained connection to the land. Further empirical research among other Indigenous People or nomadic groups on wellbeing loss and climate-induced involuntary immobility is urgently needed. Future research should particularly explore how such mental health impacts tie into past and present (post)colonial traumas and current suicide occurrences. This will help climate policy, research, and adaptation planning better prepare and propose more contextually and culturally appropriate health actions in the future.
Si/SiO2 silicon-on-insulator based scaffold for interfacing with cerebral organoids
Authors: Delahanty Aaron , Shaikh Sohail Faizan , Salmon Idris , Andrei Alexandru , Okudur Oguzhan Orkut , Gonzalez Mario , Lagae Liesbet , Ranga Adrian , Braeken Dries
Published: February 2024

Cerebral organoids are hSPC derived tissue complexes that self-organize over an extended period and begin to recapitulate certain features of in vivo neurogenesis, and there is a need to develop tools that allow for the physical and electrical interrogation of these cell complexes as they mature. Presented here is a method of manufacturing thin, porous, scalable silicon scaffolds as a structure to support multi-electrode arrays using industry standard semiconductor fabrication techniques. Mechanical tests by nanoindentation demonstrate the scaffold as linearly elastic with an approximated effective stiffness of 51.6 MPa. Biological cell studies indicate that mature Cerebral Organoids are capable of cellular expansion through, and partially absorbing, the scaffold, with 0.125 mm3 ± 0.027 of new tissue generation over a 5-day culture period. The structure is designed for compatibility with front end of line and back end of line semiconductor processes for future integration with metal electrodes, which enables deep tissue access in multi-cellular structures.
Spin-dependent recombination affected by post-annealing of organic photovoltaic devices
Authors: Suzuki Takayuki , Marumoto Kazuhiro
Published: February 2024

Organic photovoltaic devices (OPVs) are attracting attention because of recent rapid enhancement of their power conversion efficiency. For further improvement, optimization of fabrication processes is one useful path to a solution. During OPV fabrication, particularly of the bulk heterojunction active layer, annealing treatments contribute to the device performance. Many studies have examined annealing-related properties. However, further research must clarify how paramagnetic species in the devices play their roles by annealing. Using well-known OPVs, we investigated the relation between spin-dependent recombination (SDR) current and the paramagnetic species, which vary the numbers by post-annealing with active layers consisting of poly(3-hexylthiophene-2,5-diyl) (P3HT) and [6,6]-phenyl-C61-butyric acid methyl ester (PC61BM). A simultaneous detection method of electron spin resonance (ESR) and electrically detected magnetic resonance (EDMR), which we originally developed, was applied to OPVs for the first time ever reported. Results show that PC61BM anion radicals generated by post-annealing of P3HT:PC61BM OPVs with a lithium fluoride (LiF)/aluminum (Al) electrode do not contribute to the SDR current at the interface and that P3HT cation radicals enhance the SDR current. By contrast, devices with an Al electrode without LiF decrease the total SDR current, although the quantities of cation radical molecules do not vary. This finding suggests that changes of the hole blocking layer in the devices caused by the annealing treatment affect the size of capture cross sections of P3HT cation radicals. Our new method of quantitative observation of the EDMR changes through the ESR signals is expected to be useful for investigating the capture cross sections in OPVs.
Divertor turbulent transport in the single null and snowflake in the TCV tokamak
Authors: Tsui C. K. , Boedo J. A. , Myra J. R. , Galassi D. , Wüthrich C. ,   TCV Team
Published: February 2024

The relative importance of divertor radial turbulent particle fluxes is considered by comparing it against the fluxes in the main-chamber outer midplane (OMP) in a variety of conditions and divertor geometries in the tokamak à configuration variable. Within the first power falloff length, the radial turbulent fluxes in the leg of the outer divertor are consistently found to be small, and about 1/5th the magnitude measured at the OMP. In a low-density single null divertor, magnetic shear is found to play a strong role in isolating the main-chamber turbulence from the divertor. The snowflake divertor is purported to have turbulence-enhancing properties in the volume between the two X-points but was instead found to further reduce the divertor turbulent fluxes compared to the single null. Depending on the collisionality, the electric field fluctuations and radial turbulent fluxes were higher near the X-point than at the outer midplane, which is likely due to the binormal compression of the flux bundles consistent with analytical models of the resistive X-point mode. Density and potential fluctuation amplitudes decrease monotonically with distance from the OMP with a slope that depends on collisionality.
Electron effective mass in GaN revisited: New insights from terahertz and mid-infrared optical Hall effect
Authors: Armakavicius Nerijus , Knight Sean , Kühne Philipp , Stanishev Vallery , Tran Dat Q. , Richter Steffen , Papamichail Alexis , Stokey Megan , Sorensen Preston , Kilic Ufuk , Schubert Mathias , Paskov Plamen P. , Darakchieva Vanya
Published: February 2024

Electron effective mass is a fundamental material parameter defining the free charge carrier transport properties, but it is very challenging to be experimentally determined at high temperatures relevant to device operation. In this work, we obtain the electron effective mass parameters in a Si-doped GaN bulk substrate and epitaxial layers from terahertz (THz) and mid-infrared (MIR) optical Hall effect (OHE) measurements in the temperature range of 38–340 K. The OHE data are analyzed using the well-accepted Drude model to account for the free charge carrier contributions. A strong temperature dependence of the electron effective mass parameter in both bulk and epitaxial GaN with values ranging from (0.18 ± 0.02) m0 to (0.34 ± 0.01) m0 at a low temperature (38 K) and room temperature, respectively, is obtained from the THz OHE analysis. The observed effective mass enhancement with temperature is evaluated and discussed in view of conduction band nonparabolicity, polaron effect, strain, and deviations from the classical Drude behavior. On the other hand, the electron effective mass parameter determined by MIR OHE is found to be temperature independent with a value of (0.200 ± 0.002) m0. A possible explanation for the different findings from THz OHE and MIR OHE is proposed.
Dynamic evolutions of Bohm sheaths and pre-sheaths
Authors: Kono Mitsuo , Pécseli Hans L.
Published: February 2024

The time evolutions of the Bohm sheath and the related pre-sheath are analyzed as an initial value problem. The standard classical fluid model of a collisionless plasma is used with cold ions and Boltzmann distributed electrons. Numerical solutions of the basic equations show that a stationary plasma sheath itself is established within a few ion plasma periods. It is demonstrated analytically that for infinitely extended homogeneous plasmas in one spatial dimension, the only possible pre-sheath solution is dynamic, giving a steady expansion: no stationary solution exists for this one-dimensional case. The potential and density drops along the dynamic pre-sheath differ notably from the values found for stationary models suggested in the literature. Collisions give only formal changes to the collisionless results, and their substance remains the same in one spatial dimension. Cylindrical and spherical geometries, on the other hand, allow for physically acceptable, fully nonlinear, stationary solutions with analytical results given. These are supported by numerical solutions.