bluuebunny/crossref_metadata_2025 huggingface dataset:
Learning from models: high-dimensional analyses on the performance of machine learning interatomic potentials
Authors: Liu Yunsheng , Mo Yifei
Published: July 2024

Machine learning interatomic potential (MLIP) has been widely adopted for atomistic simulations. While errors and discrepancies for MLIPs have been reported, a comprehensive examination of the MLIPs’ performance over a broad spectrum of material properties has been lacking. This study introduces an analysis process comprising model sampling, benchmarking, error evaluations, and multi-dimensional statistical analyses on an ensemble of MLIPs for prediction errors over a diverse range of properties. By carrying out this analysis on 2300 MLIP models based on six different MLIP types, several properties that pose challenges for the MLIPs to achieve small errors are identified. The Pareto front analyses on two or more properties reveal the trade-offs in different properties of MLIPs, underscoring the difficulties of achieving low errors for a large number of properties simultaneously. Furthermore, we propose correlation graph analyses to characterize the error performances of MLIPs and to select the representative properties for predicting other property errors. This analysis process on a large dataset of MLIP models sheds light on the underlying complexities of MLIP performance, offering crucial guidance for the future development of MLIPs with improved predictive accuracy across an array of material properties.
CRISPRi–TnSeq maps genome-wide interactions between essential and non-essential genes in bacteria
Authors: Jana Bimal , Liu Xue , Dénéréaz Julien , Park Hongshik , Leshchiner Dmitry , Liu Bruce , Gallay Clément , Zhu Junhao , Veening Jan-Willem , van Opijnen Tim
Published: July 2024

Genetic interactions identify functional connections between genes and pathways, establishing gene functions or druggable targets. Here we use CRISPRi–TnSeq, CRISPRi-mediated knockdown of essential genes alongside TnSeq-mediated knockout of non-essential genes, to map genome-wide interactions between essential and non-essential genes in Streptococcus pneumoniae. Transposon-mutant libraries constructed in 13 CRISPRi strains enabled screening of ~24,000 gene pairs. This identified 1,334 genetic interactions, including 754 negative and 580 positive interactions. Network analyses show that 17 non-essential genes pleiotropically interact with more than half the essential genes tested. Validation experiments confirmed that a 7-gene subset protects against perturbations. Furthermore, we reveal hidden redundancies that compensate for essential gene loss, relationships between cell wall synthesis, integrity and cell division, and show that CRISPRi–TnSeq identifies synthetic and suppressor-type relationships between both functionally linked and disparate genes and pathways. Importantly, in species where CRISPRi and Tn-Seq are established, CRISPRi–TnSeq should be straightforward to implement.
FHIR-standardized data collection on the clinical rehabilitation pathway of trans-femoral amputation patients
Authors: Arcobelli Valerio Antonio , Moscato Serena , Palumbo Pierpaolo , Marfoglia Alberto , Nardini Filippo , Randi Pericle , Davalli Angelo , Carbonaro Antonella , Chiari Lorenzo , Mellone Sabato
Published: July 2024

Lower limb amputation is a medical intervention which causes motor disability and may compromise quality of life. Several factors determine patients’ health outcomes, including an appropriate prosthetic provision and an effective rehabilitation program, necessitating a thorough quantitative observation through different data sources. In this context, the role of interoperability becomes essential, facilitating the reuse of real-world data through the provision of structured and easily accessible databases. This study introduces a comprehensive 10-year dataset encompassing clinical features, mobility measurements, and prosthetic knees of 1006 trans-femoral amputees during 1962 hospital stays for rehabilitation. The dataset is made available in both comma-separated values (CSV) format and HL7 Fast Healthcare Interoperability Resources (FHIR)-based representation, ensuring broad utility and compatibility for researchers and healthcare practitioners. This initiative contributes to advancing community understanding of post-amputation rehabilitation and underscores the significance of interoperability in promoting seamless data sharing for meaningful insights into healthcare outcomes.
Two chromosome-level genome assemblies of galling aphids Slavum lentiscoides and Chaetogeoica ovagalla
Authors: Xu Shifen , Jiang Liyun , Zou Zhengting , Zou Ming , Qiao Gexia , Chen Jing
Published: July 2024

Slavum lentiscoides and Chaetogeoica ovagalla are two aphid species from the subtribe Fordina of Fordini within the subfamily Eriosomatinae, and they produce galls on their primary host plants Pistacia. We assembled chromosome-level genomes of these two species using Nanopore long-read sequencing and Hi-C technology. A 332 Mb genome assembly of S. lentiscoides with a scaffold N50 of 19.77 Mb, including 11,747 genes, and a 289 Mb genome assembly of C. ovagalla with a scaffold N50 of 11.85 Mb, containing 14,492 genes, were obtained. The Benchmarking Universal Single-Copy Orthologs (BUSCO) benchmark of the two genome assemblies reached 93.7% (91.9% single-copy) and 97.0% (95.3% single-copy), respectively. The high-quality genome assemblies in our study provide valuable resources for future genomic research of galling aphids.
Avoidance of specific calibration sessions in motor intention recognition for exoskeleton-supported rehabilitation through transfer learning on EEG data
Authors: Kueper Niklas , Kim Su Kyoung , Kirchner Elsa Andrea
Published: July 2024

Exoskeleton-based support for patients requires the learning of individual machine-learning models to recognize movement intentions of patients based on the electroencephalogram (EEG). A major issue in EEG-based movement intention recognition is the long calibration time required to train a model. In this paper, we propose a transfer learning approach that eliminates the need for a calibration session. This approach is validated on healthy subjects in this study. We will use the proposed approach in our future rehabilitation application, where the movement intention of the affected arm of a patient can be inferred from the EEG data recorded during bilateral arm movements enabled by the exoskeleton mirroring arm movements from the unaffected to the affected arm. For the initial evaluation, we compared two trained models for predicting unilateral and bilateral movement intentions without applying a classifier transfer. For the main evaluation, we predicted unilateral movement intentions without a calibration session by transferring the classifier trained on data from bilateral movement intentions. Our results showed that the classification performance for the transfer case was comparable to that in the non-transfer case, even with only 4 or 8 EEG channels. Our results contribute to robotic rehabilitation by eliminating the need for a calibration session, since EEG data for training is recorded during the rehabilitation session, and only a small number of EEG channels are required for model training.
ChaQra: a cellular unit of the Indian quantum network
Authors: Gupta Shashank , Agarwal Iteash , Mogiligidda Vijayalaxmi , Kumar Krishnan Rajesh , Chennuri Sruthi , Aggarwal Deepika , Hoodati Anwesha , Cooper Sheroy , Ranjan  , Bilal Sheik Mohammad , Bhavya K. M. , Hegde Manasa , Krishna M. Naveen , Chauhan Amit Kumar , Korrapati Mallikarjun , Singh Sumit , Singh J. B. , Sud Sunil , Gupta Sunil , Pant Sidhartha , Sankar  , Agrawal Neha , Ranjan Ashish , Mohapatra Piyush , Roopak T. , Ahmad Arsh , Nanjunda M. , Singh Dilip
Published: July 2024

Major research interests on quantum key distribution (QKD) are primarily focused on increasing 1. Point-to-point transmission distance (1000 km). 2. Secure key rate (Mbps). 3. Security of quantum layer (device-independence). It is great to push the boundaries in these fronts but these isolated approaches are neither scalable nor cost-effective due to requirements of specialised hardware and different infrastructure. Current and future QKD network requires addressing different set of challenges apart from distance, key rate and quantum security. In this regard, we present ChaQra—a sub quantum network with core features as 1. Crypto agility (integration in the already deployed telecommunication fibres). 2. Software defined networking (SDN paradigm for routing different nodes). 3. reliability (addressing denial-of-service with hybrid quantum safe cryptography). 4. upgradability (modules upgradation based on scientific and technological advancements). 5. Beyond QKD (using QKD network for distributed computing, multi-party computation etc). Our results demonstrate a clear path to create and accelerate quantum secure Indian subcontinent under national quantum mission.
Diel transcriptional responses of coral-Symbiodiniaceae holobiont to elevated temperature
Authors: Gong Sanqiang , Liang Jiayuan , Xu Lijia , Wang Yongzhi , Li Jun , Jin Xuejie , Yu Kefu , Zhang Yuehuan
Published: July 2024

Coral exhibits diel rhythms in behavior and gene transcription. However, the influence of elevated temperature, a key factor causing coral bleaching, on these rhythms remains poorly understood. To address this, we examined physiological, metabolic, and gene transcription oscillations in the Acropora tenuis-Cladocopium sp. holobiont under constant darkness (DD), light-dark cycle (LD), and LD with elevated temperature (HLD). Under LD, the values of photosystem II efficiency, reactive oxygen species leakage, and lipid peroxidation exhibited significant diel oscillations. These oscillations were further amplified during coral bleaching under HLD. Gene transcription analysis identified 24-hour rhythms for specific genes in both coral and Symbiodiniaceae under LD. Notably, these rhythms were disrupted in coral and shifted in Symbiodiniaceae under HLD. Importantly, we identified over 20 clock or clock-controlled genes in this holobiont. Specifically, we suggested CIPC (CLOCK-interacting pacemaker-like) gene as a core clock gene in coral. We observed that the transcription of two abundant rhythmic genes encoding glycoside hydrolases (CBM21) and heme-binding protein (SOUL) were dysregulated by elevated temperature. These findings indicate that elevated temperatures disrupt diel gene transcription rhythms in the coral-Symbiodiniaceae holobiont, affecting essential symbiosis processes, such as carbohydrate utilization and redox homeostasis. These disruptions may contribute to the thermal bleaching of coral.
Performance of quantum annealing inspired algorithms for combinatorial optimization problems
Authors: Zeng Qing-Guo , Cui Xiao-Peng , Liu Bowen , Wang Yao , Mosharev Pavel , Yung Man-Hong
Published: July 2024

Two classes of quantum-annealing-inspired-algorithms (QAIA), namely different variants of simulated coherent Ising machine and simulated bifurcation, have been proposed for efficiently solving combinatorial optimization problems recently. In order to certify the superiority of these algorithms, standardized comparisons among them and against other physics-based algorithms are necessary. In this work, for Max-Cut problems up to 20,000 nodes, we benchmark QAIA against quantum annealing and other physics-based algorithms. We found that ballistic simulated bifurcation excelled for chimera and small-scale graphs, achieving nearly a 50-fold reduction in time-to-solution compared to quantum annealing. For large-scale graphs, discrete simulated bifurcation achieves the lowest time-to-target and outperforms D-Wave Advantage system when tasked with finding the maximum cut value in pegasus graphs. Our results suggest that QAIA represents a promising means for solving combinatorial optimization problems in practice, and can act as a natural baseline for competing quantum algorithms.
Metal-organic framework single crystal for in-memory neuromorphic computing with a light control
Authors: Bachinin Semyon V. , Marunchenko Alexandr , Matchenya Ivan , Zhestkij Nikolai , Shirobokov Vladimir , Gunina Ekaterina , Novikov Alexander , Timofeeva Maria , Povarov Svyatoslav A. , Li Fengting , Milichko Valentin A.
Published: July 2024

Neuromorphic architectures, expanding the limits of computing from conventional data processing and storage to advanced cognition, learning, and in-memory computing, impose restrictions on materials that should operate fast, energy efficiently, and highly endurant. Here we report on in-memory computing architecture based on metal-organic framework (MOF) single crystal with a light control. We demonstrate that the MOF with inherent memristive behavior (for data storage) changes nonlinearly its electric response when irradiated by light. This leads to three and more electronic states (spikes) with 81 ms duration and 1 s refractory time, allowing to implement 40 bits s−1 optoelectronic data processing. Next, the architecture is switched to the neuromorphic state upon the action of a set of laser pulses, providing the text recognition over 50 times with app. 100% accuracy. Thereby, simultaneous data storage, processing, and neuromorphic computing on MOF, driven by light, pave the way for multifunctional in-memory computing architectures.
Fast in-line failure analysis of sub-micron-sized cracks in 3D interconnect technologies utilizing acoustic interferometry
Authors: Paulachan Priya , Hammer René , Siegert Joerg , Wiesler Ingo , Brunner Roland
Published: July 2024

More than Moore technology is driving semiconductor devices towards higher complexity and further miniaturization. Device miniaturization strongly impacts failure analysis (FA), since it triggers the need for non-destructive approaches with high resolution in combination with cost and time efficient execution. Conventional scanning acoustic microscopy (SAM) is an indispensable tool for failure analysis in the semiconductor industry, however resolution and penetration capabilities are strongly limited by the transducer frequency. In this work, we conduct an acoustic interferometry approach, based on a SAM-setup utilizing 100 MHz lenses and enabling not only sufficient penetration depth but also high resolution for efficient in-line FA of Through Silicon Vias (TSVs). Accompanied elastodynamic finite integration technique-based simulations, provide an in-depth understanding concerning the acoustic wave excitation and propagation. We show that the controlled excitation of surface acoustic waves extends the contingency towards the detection of nm-sized cracks, an essential accomplishment for modern FA of 3D-integration technologies.
LILRB1-HLA-G axis defines a checkpoint driving natural killer cell exhaustion in tuberculosis
Authors: Wang Jing , Chai Qiyao , Lei Zehui , Wang Yiru , He Jiehua , Ge Pupu , Lu Zhe , Qiang Lihua , Zhao Dongdong , Yu Shanshan , Qiu Changgen , Zhong Yanzhao , Li Bing-Xi , Zhang Lingqiang , Pang Yu , Gao George Fu , Liu Cui Hua
Published: July 2024

Chronic infections, including Mycobacterium tuberculosis (Mtb)-caused tuberculosis (TB), can induce host immune exhaustion. However, the key checkpoint molecules involved in this process and the underlying regulatory mechanisms remain largely undefined, which impede the application of checkpoint-based immunotherapy in infectious diseases. Here, through adopting time-of-flight mass cytometry and transcriptional profiling to systematically analyze natural killer (NK) cell surface receptors, we identify leukocyte immunoglobulin like receptor B1 (LILRB1) as a critical checkpoint receptor that defines a TB-associated cell subset (LILRB1+ NK cells) and drives NK cell exhaustion in TB. Mechanistically, Mtb-infected macrophages display high expression of human leukocyte antigen-G (HLA-G), which upregulates and activates LILRB1 on NK cells to impair their functions by inhibiting mitogen-activated protein kinase (MAPK) signaling via tyrosine phosphatases SHP1/2. Furthermore, LILRB1 blockade restores NK cell-dependent anti-Mtb immunity in immuno-humanized mice. Thus, LILRB1-HLA-G axis constitutes a NK cell immune checkpoint in TB and serves as a promising immunotherapy target.
Characterization of Injectable Smart Hydrogels
Authors: Gil-Cabrerizo P. , Del Campo-Montoya R. , Sancho A. , Aldazabal J. , Paredes J. , Blanco-Prieto M. J. , Garbayo E.
Published: July 2024

Injectable smart hydrogels are water-swollen polymeric structures able to respond to different stimuli such as changes in temperature or pH. They also allow minimally invasive administration, which greatly increases their translational potential. The characterization of these biomaterials is essential to understand their functionality and to ensure their directed development. Due to the unique characteristics of injectable smart hydrogels, several tests should be performed before and after their gelation or stimuli-induced changes. However, there is a lack of standardized methodology for assessing hydrogel properties as well as great heterogeneity in how they are characterized. Throughout this chapter, different characterization techniques to assess these properties as well as key considerations for adequately characterizing smart injectable hydrogels will be discussed. Among the main properties that need characterization, hydrogel rheology, structure, morphology, stability, degradation, cargo release and biocompatibility are discussed. Establishing how they should be characterized will facilitate their translation towards the clinic.
Low-cost heat assisted ambient ionization source for mass spectrometry in food and pharmaceutical screening
Authors: Gazeli Odhisea , Elia Efstathios A. , Argirusis Nikolaos , Lazarou Constantinos , Anastassiou Charalambos , Franzke Joachim , Garcia-Reyes Juan F. , Georghiou George E. , Agapiou Agapios
Published: July 2024

Ambient Ionization Mass Spectrometry (AI-MS) techniques have revolutionized analytical chemistry by enabling rapid analysis of samples under atmospheric conditions with minimal to no preparation.
A diastereoselective strategy for dihydrophenanthrene-fused spirooxindoles via [1,2]-phospha-Brook rearrangement
Authors: Ali Amjad , Harit Harish K. , Behera Chandana , Singh Ravi P.
Published: July 2024

A highly diastereoselective, one-pot strategy for spirooxindoles bearing dihydrophenanthrenes from readily available isatins and p-quinone methides (p-QMs) has been disclosed.
Cascading responses of stimuli-responsive materials
Authors: Oaki Yuya , Fujii Syuji
Published: July 2024

Cascading responses are a new concept for integrating stimulus-responsive materials to obtain output responses from the original input stimulus through successive conversions of the stimuli in a system.
Probing photoinduced electron transfer events in phenylferrocene–corrole dyad
Authors: Takkella Dineshbabu , Sharma Sudhanshu , Samireddi Satyanarayana , Gavvala Krishna
Published: July 2024

In this study, we investigated the electron transfer mechanism in a corrole-based donor–acceptor (D–A) dyad (10-phenylferrocenyl-5,15-diphenyl corrole) using spectroscopic and computational methods.
Photosubstitution and photoreduction of a diazido platinum(iv) anticancer complex
Authors: Shi Huayun , Ward-Deitrich Christian , Ponte Fortuna , Sicilia Emilia , Goenaga-Infante Heidi , Sadler Peter J.
Published: July 2024

HPLC-ICPMS with LC-MS allows identification of products from photoactivation of a diazido Pt(iv) anticancer complex by visible light under physiologically-relevant conditions, including novel polyhyroxido Pt(iv) species, potential pharmacophores.
Trehalose in cryopreservation. Applications, mechanisms and intracellular delivery opportunities
Authors: Murray Alex , Kilbride Peter , Gibson Matthew I.
Published: July 2024

The state of the art, challenges and opportunities for chemists to engineer and deliver trehalose as a cryoprotectant to address challenges in biomedicine and biotechnology are reviewed.
Carbon-supported nickel/nickel oxide nanohybrid composite as a high-performance sensor for electrochemical non-enzymatic glucose detection
Authors: Ramu Jagadish , Ramasundaram Subramaniyan , Yellappa Shivaraj , Gunamalai Lavanya , Kamilya Tapas , Afzal Mohd , Jeffery A. Anto , Oh Tae Hwan , Mahanthappa Mallappa , Vishwanath R. S.
Published: July 2024

Electrocatalytic oxidation of glucose on carbon-supported nickel/nickel oxide nanocomposite modified GCE.
Achieving a Eu2+-doped NIR phosphor via ionic modulation and its multifunctional applications
Authors: Gong Jie , Li Panlai , Gao Bingkai , Liu Mengdi , Yan Zekang , Guo Dongxu , Feng Xiuxiu , Zhang Ting , Li Xiaojie , Wang Zhijun
Published: July 2024

Ca(1−x)SrxO:Eu2+ can be applied to biological tissue penetration and night vision illumination.
Combined effect of amino nitrogen and pyridine nitrogen for tetracycline adsorption on aminopyridine modified MIL-101(Cr)
Authors: Ma Tiantian , Liu Haixin , Qi Luming , Dou Zhenjiang , Liu Qing , Fei Zhaoyang , Chen Xian , Zhang Zhuxiu , Tang Jihai , Qiao Xu
Published: July 2024

xApy-MIL-101(Cr) was successfully synthesized by incorporating 4-aminopyridine, and it was employed for adsorption of tetracycline in wastewater.
International Symposium on Inorganic Environmental Materials 2023 (ISIEM 2023)
Authors: Fujimoto Kenjiro , Aizawa Mamoru , Matsumoto Naoyuki , Mori Hiroaki
Published: July 2024

Introduction to the International Symposium on Inorganic and Environmental Materials 2023 themed issue.
Visible-light-induced alkyl-arylation of olefins via a halogen-atom transfer process
Authors: Ren Juan , Xia Xiao-Feng
Published: July 2024

Visible-light-induced three-component 1,2-alkyl-arylation of alkenes and alkyl radical addition/cyclization of acrylamides have been realized using a photocatalytic halogen-atom transfer (XAT) strategy.
Video Modeling to Support Social Communication Goals of Autistic Adults: A Tutorial
Authors: Wilson Kaitlyn P. , Valazza Emily , Price Carrie
Published: July 2024

Purpose:

Decades of research have shown video modeling to be an effective tool for teaching and supporting a variety of skills in autistic children. More recently, video modeling has emerged as an effective support for autistic adults, with much of the literature focused on vocational success through support of language skills. The purpose of this tutorial is to provide speech-language pathologists, autistic adults, and other team members with evidence-based guidelines for use of video modeling to support success with social communication across settings.

Method:

This evidence-based tutorial draws from the literature on video modeling for autistic adults in the area of social communication, presenting empirically supported guidelines for speech-language pathologists considering video modeling as a tool to support social communication within this population and their interaction partners. This tutorial presents an evidence-based, step-by-step guide to the planning, creation, and use of video models with and by autistic adults, along with important additional considerations based on relevant literature.

Conclusions:

Video modeling is a social communication support that is backed by the scientific literature as an efficacious tool for use by autistic adults. This tutorial will guide speech-language pathologists' use of this evidence-based tool as they work alongside autistic adults and others to help meet social communication goals across settings.
Observation clinique - Prévention temporaire des chaleurs
chez une chatte reproductrice
Authors: Gogny Anne , Topie Emmanuel
Published: July 2024

Une chatte reproductrice, de race Russe, âgée de 3 ans, est présentée pour suppression temporaire des chaleurs. Elle reçoit un implant de desloréline dosé à 4,7 mg, injecté dans la région péri-ombilicale. Trois jours après l'injection, la chatte exprime des chaleurs, s'échappe et débute une gestation. Celle-ci est interrompue avec de l'aglépristone.

Aucun autre œstrus n'est observé pendant les 6 mois qui suivent. Après cette période, l'implant est ôté sous anesthésie générale.

La chatte présente des chaleurs 3,5 mois plus tard. Elle est saillie pendant 3 jours consécutifs par un mâle de la même race, et donne naissance à 4 chatons, tous viables et normaux.

Quatre, puis onze mois après cette mise bas, elle est de nouveau saillie accidentellement par un chat du voisinage. A chaque fois, la gestation est interrompue avec de l'aglépristone.

Quel que soit le produit employé pour contrôler les chaleurs, la reprise de la fertilité après traitement est la principale préoccupation en élevage.

Cette observation clinique présente un exemple de reprise réussie de la fertilité après traitement par un implant de desloréline à action prolongée.
Comparison of Characteristics and Outcomes of Multisystem Inflammatory Syndrome and Prepandemic Kawasaki's Disease
Authors: Ünlü Neşe , Özel Abdulrahman , Büke Övgü , Onan Sertaç Hanedan , Tenekecigil Aslıhan , Erol Meltem , Gayret Özlem Bostan
Published: July 2024

Objective In this study, our objective is to compare the demographic, clinical, laboratory, and echocardiographic findings of patients with multisystem inflammatory syndrome in children (MIS-C) and Kawasaki's disease (KD) diagnosed in the prepandemic period.

Methods We retrospectively collected data from all pediatric patients who met the Centers for Disease Control and Prevention's MIS-C case definition and who met the American Heart Association's definition of complete KD before the coronavirus disease 2019 pandemic.

Results A total of 37 patients diagnosed with MIS-C and 40 patients diagnosed with complete KD were included. Gastrointestinal findings were significantly higher in the MIS-C group than in the KD group (vomiting [p = 0.009], diarrhea [p = 0.009]). The incidence of thrombocytopenia (48.6%) was significantly higher in the MIS-C group. Regarding inflammatory markers, procalcitonin and ferritin were significantly higher in the MIS-C group (p = 0.032 and p = 0.006) and the erythrocyte sedimentation rate was higher in the KD group (p < 0.001). Pericardial effusion and mitral valve regurgitation were significantly more frequent in the MIS-C group (p = 0.024 and p = 0.001).

Conclusion Although they have similar findings, our current study findings show that MIS-C and KD differ from each other with different clinical and laboratory features. We think that these differences will help clinicians in diagnosis and patient management.
Young people as a political subject in the context of environmental governance
Authors: Rodela Romina , Roumeliotis Filip
Published: July 2024

The discourse on environmental challenges has evolved significantly in recent years, with climate change emerging as a central global concern. This transformation has been heavily influenced by the last wave of youth-led social movements, notably the Fridays for Future movement, who have mobilized young people at a global scale contributing at a shift in public discourse on the topic of climate action. However, despite the impact of the newly emerged youth-led movements it is still rather unclear if and where has youth gained recognition as a group with special interests within environmental policy and governance. In this study we report on a research were we investigated the positioning of youth in contemporary environmental governance, and propose a theoretical perspective to understand how the subject category of “youth” is constructed in public discourse and its implications for political recognition. We study the progressive emergence of Greta Thunberg as a voice for a generation of youth climate activists and undertake a document analysis of selected material generated in relation to selected international political events. By addressing questions of recognition, discourse structure, and legitimacy, this research aims to shed light on the nuanced dynamics shaping the role of youth in environmental policy and governance.
Computer simulation of the density of states and band structure of NaF nanotubes
Authors: Istlyaup Assel , Myasnikova Lyudmila , Sergeyev Daulet , Konuhova Marina , Popov Anatoli I.
Published: July 2024

Modern solid-state physics increasingly focuses on the study of nanomaterials and the development of nanotechnologies. Various theoretical methods and research technologies are actively used to elucidate the significance of experimental results related to the study of solid-state defects. Progress in this field is likely associated with advancements in computer technologies and the development of modern quantum-chemical packages. The obtained spectra reveal a certain number of energy levels in the energy range from –30 to 20 eV. We determine the band structure, density of states, and total energy of NaF nanotubes with parameters (m, n), where m = 4, 5, 6, 8, and n = 1, 2, 3. The characteristics modeling is conducted using the Atomistix ToolKit software package and Virtual NanoLab program. This work presents the results of computer modeling of the density of states and total energy of NaF nanotubes within the framework of density functional theory. The obtained results allow classifying the tubular structures of NaF as quantum dots and contribute to further research into alkali metal halide crystals in nanostructures.
Phonon hydrodynamics in bulk insulators and semimetals
Authors: Machida Yo , Martelli Valentina , Jaoui Alexandre , Fauqué Benoît , Behnia Kamran
Published: July 2024

Decades ago, Gurzhi proposed that if momentum-conserving collisions prevail among heat-carrying phonons in insulators and charge-carrying electrons in metals, hydrodynamic features will become detectable. In this paper, we will review the experimental evidence emerging in the last few years supporting this viewpoint and raising new questions. The focus of the paper will be bulk crystals without (or with a very dilute concentration of) mobile electrons and steady-state thermal transport. We also discuss the possible link between this field of investigation and other phenomena, such as the hybridization of phonon modes and the phonon thermal Hall effect.
Non-smoothness of the fundamental solutions for Schrödinger equations with super-quadratic and spherically symmetric potential
Authors: Kato Keiichi , Nakahashi Wataru , Tadano Yukihide
Published: July 2024

We study non-smoothness of the fundamental solution for the Schrödinger equation with a spherically symmetric and super-quadratic potential in the sense that V(x) ≥ C|x|2+ɛ at infinity with constants C > 0 and ɛ > 0. More precisely, we show the fundamental solution E(t, x, y) does not belong to C1 as a function of (t, x, y), which partially solves Yajima’s conjecture.
A cryogenic forced oscillation apparatus to measure anelasticity of ice
Authors: Yamauchi Hatsuki , McCarthy Christine , Leeman John R. , Holtzman Benjamin K.
Published: July 2024

We have developed a new cryogenic uni-axial forced oscillation apparatus to measure the anelastic behavior of ice by adapting the design of a previous high-precision apparatus for use in low-temperature (<0 °C) conditions. With this new apparatus, Young’s modulus and attenuation can be measured over a broad frequency range from 10−4 to 10 Hz. We have performed calibration tests with standard materials (steel spring, stainless steel, and acrylic samples) under various conditions to assess the apparatus properties and correct the effects on the obtained raw data. Young’s modulus and attenuation for an acrylic sample after all of the data corrections show good agreement with previously published values, demonstrating the validity of the data corrections and reliability of the obtained data. We further obtained a preliminary dataset of Young’s modulus and attenuation for an ice polycrystalline sample under small median stress and small stress amplitude. The anelastic response was not strain amplitude-dependent, that is, the response is linear. Moreover, the attenuation data are consistent with the data measured for other polycrystalline materials under similarly small stress conditions in terms of the Maxwell frequency scaling, which is known as a scaling law applicable to linear anelasticity induced by the diffusionally accommodated grain boundary sliding mechanism. Although there is still room for improving the control of testing conditions, we show that the new forced oscillation apparatus is capable of systematic studies on the anelastic properties of ice, the subject of future studies.
Mode distribution impact on photonic crystal surface emitting laser performance
Authors: Gautam Chhabindra , Pan Mingsen , Seth Subhashree , Rotter Thomas J. , Zhou Ming , Thompson Bradley J. , Gibson Ricky , Fan Shanhui , Balakrishnan Ganesh , Zhou Weidong
Published: July 2024

As a new type of semiconductor laser, photonic crystal surface-emitting lasers (PCSELs) feature large-area single-mode surface emission with high power and high beam quality. The unique features of single-mode lasing over a large area active region are implemented by the in-plane optical feedback from two-dimensional (2D) photonic crystal cavities. In larger PCSEL cavities, the lasing gain threshold becomes similar for the fundamental and high-order modes, which degrades single-mode operation. Here, we investigate the impact of carrier injection on PCSEL modes by controlling the injection area and the gain mode interaction. Optical and electrical simulations are carried out to calculate the gain mode overlapping factor for different p electrode designs. We fabricated 250 × 250 µm2 photonic crystal cavities with different p electrode sizes for injection area control. The PCSEL device characterization results show that devices with an electrode size to cavity side length ratio of 0.6 have the maximum slope efficiency and a lower lasing threshold with a single lobe beam profile. Such selective carrier injection can also provide gain-guided resonance in the PCSEL cavities and enhance optical gain in the fundamental mode while suppressing gain in the high-order modes.
Recurrence microstates for machine learning classification
Authors: Spezzatto G. S. , Flauzino J. V. V. , Corso G. , Boaretto B. R. R. , Macau E. E. N. , Prado T. L. , Lopes S. R.
Published: July 2024

Recurrence microstates are obtained from the cross recurrence of two sequences of values embedded in a time series, being the generalization of the concept of recurrence of a given state in phase space. The probability of occurrence of each microstate constitutes a recurrence quantifier. The set of probabilities of all microstates are capable of detecting even small changes in the data pattern. This creates an ideal tool for generating features in machine learning algorithms. Thanks to the sensitivity of the set of probabilities of occurrence of microstates, it can be used to feed a deep neural network, namely, a microstate multi-layer perceptron (MMLP) to classify parameters of chaotic systems. Additionally, we show that with more microstates, the accuracy of the MMLP increases, showing that the increasing size and number of microstates insert new and independent information into the analysis. We also explore potential applications of the proposed method when adapted to different contexts.
Production of green hydrogen in Brazil for exportation from desalinated seawater using energy generated by heliothermal, photovoltaic, and wind plants
Authors: Neto José Henrique Martins
Published: July 2024

A current global trend is the production of green hydrogen via electrolysis of fresh water, preferably extracted from regions that have an abundance of renewable energy, to contribute to the mitigation of global warming. Despite being considered a source of fresh water, Brazil is experiencing a water crisis, with a shortage of water to meet agriculture and hydroelectric generation due to climate effects that affect the water cycle. With the forecast of increasing population and increasing demand for fresh water for consumption, agriculture, and industry, it is necessary to investigate opportunities for the generation of green hydrogen. This article presents results of technical and economic feasibility analyses of eight green hydrogen production systems for export, derived from two main concepts of seawater desalination plants aimed at preserving freshwater for other more noble purposes. All the analyzed systems use electrical and (or) thermal energy generation plants derived from solar and wind energy, with emphasis on heliothermal energy concentration systems. It is observed that the heliothermal systems, generators of electric and thermal energy, require higher investment costs; however, they have hydrogen production costs compatible with those of the other systems and dispatchable daily production of hydrogen and desalinated water. Furthermore, a system that combines thermal energy from a heliothermal plant to drive a thermal desalination plant and electrical energy from photovoltaic and wind plants to drive the electrolyzers was very well classified. Finally, it is verified that desalination plants have negligible investment cost compared to the cost of power and hydrogen plants.
Nonlinear responses of a horizontal plate under the water impact
Authors: Moradi Hashem
Published: July 2024

The water impact of an elastic plate is an important issue in numerous engineering applications. Despite extensive research on various aspects of this subject, the nonlinear behavior of the plate's response during water impact remains unexplored. In this article, the novel contribution is the nonlinear response analysis of a plate under compressive loading when impacted with water. The geometric nonlinearity caused by midplane stretching is taken into account. Hydrodynamic pressure is determined by the velocity potential function of the flow. A fully coupled nonlinear hydroelastic equation is derived as an integrodifferential equation. This equation is simplified to the Duffing equation by expressing the deflection as a linear combination of the dry mode shapes. The Duffing equation is solved analytically using Jacobi elliptic functions. Additionally, the fixed points of the Duffing equation are examined using phase portraits of the first mode shape to identify the effects of nonlinearity on the responses. The analytical solution is verified using the Runge–Kutta method and validated against the methods available in the literature. The effects of midplane stretching on the maximum deflections, bending stresses, and wet frequencies are evaluated for various horizontal speeds and compressive loads. The results indicate that the amplitude and oscillation period of the nonlinear response are significantly smaller than those of the linear response. Furthermore, it is found that midplane stretching should be considered in modeling the impact of the elastic plate on the water.
Data-driven rogue waves solutions for the focusing and variable coefficient nonlinear Schrödinger equations via deep learning
Authors: Sun Jiuyun , Dong Huanhe , Liu Mingshuo , Fang Yong
Published: July 2024

In this paper, we investigate the data-driven rogue waves solutions of the focusing and the variable coefficient nonlinear Schrödinger (NLS) equations by the deep learning method from initial and boundary conditions. Specifically, first- and second-order rogue wave solutions for the focusing NLS equation and three deformed rogue wave solutions for the variable coefficient NLS equation are solved using physics-informed memory networks (PIMNs). The effects of optimization algorithm, network structure, and mesh size on the solution accuracy are discussed. Numerical experiments clearly demonstrate that the PIMNs can capture the nonlinear features of rogue waves solutions very well. This is of great significance for revealing the dynamical behavior of the rogue waves solutions and advancing the application of deep learning in the field of solving partial differential equations.
Enhanced current phenomenon in nanocrystalline graphite nanopore
Authors: Zhou Daming , Wang Yunjiao , Zhang Xiaoling , He Shixuan , Wang Liang , Tlili Chaker , Wang Deqiang
Published: July 2024

In the realm of nanopore sensing, one of the most fundamental questions that needs to be answered is how ions are transported through nanochannels. The changes in current caused by the molecule moving through the nanopores provide us with useful information about the size, conformation, and charge of the test substance. In this context, we have fabricated a nanometer-sized pore in a suspended nanocrystalline graphite membrane and found that when negatively charged deoxyribonucleic acid (DNA) molecules pass through the pore, the current increases. Using the Navier–Stokes and Poisson–Nernst–Planck coupling models, we calculated the current reduction due to the steric hindrance effect of DNA molecules, as well as the current increase due to the enhanced ion concentration in nanopores, which is attracted by DNA surface charges. The results from these studies provide a new nanopore material for basic and applied nanofluidic research and reveal that the electroosmotic flow plays a role in driving DNA transport and generating conductive events due to polarization effects. This finding not only expands our understanding of the physical principles governing DNA–nanopore interactions but also holds promise for advancing the sensitivity and specificity of nanopore-based molecular detection.
Data-driven optimal control of undulatory swimming
Authors: Maroun Karl , Traoré Philippe , Bergmann Michel
Published: July 2024

Achieving precise control over self-propelled undulatory swimmers requires a deep understanding of their intricate dynamics. This paper presents a method for addressing optimal control problems in this context by leveraging surrogate models. We develop a Navier–Stokes solver using a volume penalization method to simulate the fluid–structure interaction inherent in swimming dynamics. An offline phase generates training data through open-loop simulations across a defined range of control inputs, enabling the training of a surrogate model. This model significantly reduces computational costs, particularly in optimization and control contexts. Utilizing these surrogate models, we compute control strategies to address two key challenges: precise velocity tracking and optimizing swimmer efficiency. First, we employ model predictive control to enable velocity tracking against a reference signal, allowing swift adjustments of the swimmer's frequency and amplitude. Second, we tackle the minimization of the swimmer's cost of transport, resulting in a solution akin to a burst-and-coast strategy. Despite achieving energy performance comparable to continuous swimming cases, mismatches between the surrogate model and the high fidelity simulation significantly impact the quality of the obtained solution. This work sheds light on the potential of surrogate models in optimizing self-propelled swimming behavior and underscores the importance of addressing model mismatches for more accurate control strategies in the future.
Self-similar Reynolds-averaged mechanical–scalar turbulence models for Rayleigh–Taylor mixing induced by power-law accelerations in the small Atwood number limit
Authors: Schilling Oleg
Published: July 2024

Analytical self-similar solutions to two-, three-, and four-equation Reynolds-averaged mechanical–scalar turbulence models describing turbulent Rayleigh–Taylor mixing driven by a temporal power-law acceleration are derived in the small Atwood number (Boussinesq) limit. The solutions generalize those previously derived for constant acceleration Rayleigh–Taylor mixing for models based on the turbulent kinetic energy K and its dissipation rate ε, together with the scalar variance S and its dissipation rate χ [O. Schilling, “Self-similar Reynolds-averaged mechanical–scalar turbulence models for Rayleigh–Taylor, Richtmyer–Meshkov, and Kelvin–Helmholtz instability-induced mixing in the small Atwood number limit,” Phys. Fluids 33, 085129 (2021)]. The turbulent fields are expressed in terms of the model coefficients and power-law exponent, with their temporal power-law scalings obtained by requiring that the self-similar equations are explicitly time-independent. Mixing layer growth parameters and other physical observables are obtained explicitly as functions of the model coefficients and parameterized by the exponent of the power-law acceleration. Values for physical observables in the constant acceleration case are used to calibrate the two-, three-, and four-equation models, such that the self-similar solutions are consistent with experimental and numerical simulation data corresponding to a canonical (i.e., constant acceleration) Rayleigh–Taylor turbulent flow. The calibrated four-equation model is then used to numerically reconstruct the mean and turbulent fields, and turbulent equation budgets across the mixing layer for several values of the power-law exponent. The reference solutions derived here can be used to understand the model predictions for strongly accelerated or decelerated Rayleigh–Taylor mixing in the large Reynolds number limit.
Droplet impact outcomes: Effect of wettability and Weber number
Authors: Wei Bo-Jian , Liu Zhe , Shi Shi-Hua , Gao Shu-Rong , Wang Yi-Feng , Yang Yan-Ru , Wang Xiao-Dong
Published: July 2024

In this study, we experimentally explored the impact outcomes of droplets under a wide range of Weber numbers (0.2 ≤ We ≤ 200) and contact angles (91° ≤ θ ≤ 162°). Five impact outcomes were identified: deposition, rebound, partial rebound, receding breakup, and prompt splash. Compared to the literature, we gathered more comprehensive data on the impact outcomes at various contact angles, which were then organized into a complete phase diagram. Furthermore, we corroborated the accuracy of these outcomes through comparisons with other studies. We conducted a comprehensive analysis of the associated phenomena and underlying mechanisms of these outcomes. By introducing the concept of surface hysteresis energy, we also proposed identification criteria for partial rebound. This innovative approach provides an important reference for further understanding of droplet impact behavior and provides guidance for future research in this field.
Experimental investigation of tip vortex cavitation noise under static and dynamic states
Authors: Wu Kelin , Cai Haopeng , Zhang Zhengzhuang , Wang Pengzhong , Wang Lu , Cao Linlin , Huang Bin , Wu Dazhuan
Published: July 2024

Tip vortex cavitation (TVC) stands as a primary source of underwater radiated noise, garnering significant attention in the relevant fields due to its early manifestation in propellers and broad frequency spectrum. Although some meaningful experimental and numerical research concerning TVC noise has been implemented, a comprehensive understanding of TVC noise properties still remains elusive. This study delves into the acoustic characteristics of TVC through cavitation experiments of hydrofoil and jet pump and signal processing tools, including frequency-domain analysis, time-frequency representation, and signal demodulation. Comparative analysis between static and dynamic states of the test hydrofoil and the test jet pump reveals several insights into TVC noise. First, the acoustic characteristics of TVC primarily encompass multiple low-frequency characteristic peaks below 300 Hz alongside an overall increase in the high-frequency domain. Second, the oscillating hydrofoil at a cavitation number of 2.00 exhibits two distinct frequency bands caused by cavity volume variation and cavity resonance of TVC at 190–280 and 360–400 Hz, which shift toward the lower frequency region with larger TVC sizes. Finally, the periodic oscillation of hydrofoil or the rotational motion of impeller induces a modulation effect on TVC noise, with spectral correlation (SC) identifying two dominant carrier bands within 100–400 Hz.