bluuebunny/crossref_metadata_2025 huggingface dataset:
Phase stabilization via A-site ion anchoring for ultra-stable perovskite light emitting diodes
Authors: Ding Shuo , Kong Zhuoyuan , Shen Yipeng , Shen Piaoyang , Wu Chunyan , Qian Lei , Zhang Xinyu , Hu Long , Chen Hao , Xiang Chaoyu
Published: August 2024

To enhance the operational stability of perovskite light emitting diodes (PeLEDs), 1H,1H-perfluorohexylamine was employed to anchor ions and stabilize perovskite phase, yielding ambient stable film and ultra-stable PeLEDs with 37.2-year T50 lifetime.
PANDA: a self-driving lab for studying electrodeposited polymer films
Authors: Quinn Harley , Robben Gregory A. , Zheng Zhaoyi , Gardner Alan L. , Werner Jörg G. , Brown Keith A.
Published: August 2024

We report the PANDA, a self-driving lab that handles fluids, electrodeposits polymers, and then functionally characterizes the result using optics or electrochemistry. As an example application, we perform a closed-loop study of electrochromic films.
Maximizing liposome tumor delivery by hybridizing with tumor-derived extracellular vesicles
Authors: Sulthana Shoukath , Shrestha Dinesh , Aryal Santosh
Published: August 2024

This investigation highlights the maximizing of nanoparticle tumor delivery by hybridizing nanoparticles with tumor-derived-extracellular vesicles.
Fabrication and assembly of supercapacitors based on Ni-based MOFs and their derivative materials for enhancing their electrochemical performances
Authors: Li Wen-Ze , Yang Ying , Zhang Xiao-Sa , Liu Yu , Luan Jian
Published: August 2024

A series of nickel-based materials were derived from two different Ni-MOFs by calcination, and the researchers investigated the structural and electrochemical properties of these materials in detail.
Enhanced catalytic performance through a single-atom preparation approach: a review on ruthenium-based catalysts
Authors: Yang Ziyi , Liu Li , Zheng Yayun , Liu Zixuan , Wang Lin , Yang Richard (Chunhui) , Liu Zongjian , Wang Yichao , Chen Zhengfei
Published: August 2024

The outstanding catalytic properties of single-atom catalysts (SACs) stem from the maximum atom utilization and unique quantum size effects, leading to ever-increasing research interest in SACs in recent years.
Glycosphingolipids: from metabolism to chemoenzymatic total synthesis
Authors: Bonab Mitra K. F. , Guo Zhongwu , Li Qingjiang
Published: August 2024

GSL biosynthesis pathways and the enzymes involved, recombinant enzymes applied to GSL synthesis, and recent progress in related synthetic strategies are reviewed to help develop new enzymes and methods for efficient chemoenzymatic GSL synthesis.
Dual SARS-CoV-2 and MERS-CoV inhibitors from Artemisia monosperma: isolation, structure elucidation, molecular modelling studies, and in vitro activities
Authors: Badawy Ahmed M. , Donia Marwa Samir M. , Hamdy Nehal G. , El-Ayouty Mayada M. , Mohamed Osama G. , Darwish Khaled M. , Tripathi Ashootosh , Ahmed Safwat A.
Published: August 2024

The COVID-19 pandemic has spread throughout the whole globe, so it is imperative that all available resources be used to treat this scourge.
Nickel-catalysed reductive C–N bond cross-coupling between aryl halides and N-chloroamides
Authors: Luo Yiting , Yao Jiacan , He Yunzhi , Xu Chang , Liu Dandan
Published: August 2024

An unprecedented nickel-catalysed reductive cross-coupling of C–N bonds is achieved and applied to the synthesis of bioactive molecules.
Defect engineering of CH3NH3PbI3 towards enhanced carrier lifetime: combined detailed balanced study and NAMD-TDDFT
Authors: Wang Jing , Duan Xiang-Mei
Published: August 2024

An innovative defect analysis method enhances a novel understanding of perovskite solar cells, linking the growth environment, defect characteristics and device performance.
Localized photothermal effect of Co3O4 nanowires boosts catalytic performance in glucose electrochemical detection
Authors: You Teng , Xiao Shuang , Huang Ping , Wang Chunyan , Deng Qiuxia , Jiang Ping , He Daiping
Published: August 2024

Localized photothermal effect endows Co3O4 nanowires with larger electrochemical surface area and higher electric conductivity in process of glucose oxidation, giving rise to an improved performance in glucose sensing.
Recent advances in the mechanism and catalyst design in the research of aprotic, photo-assisted, and solid-state Li–CO2 batteries
Authors: Chen Haixia , Li Xijuan , Xue Hairong , Jia Lulu , Xu Yunyun , Tao Yinglei , Yan Yige , Fan Xiaoli , He Jianping , Wang Tao
Published: August 2024

This review focuses on the reaction mechanisms and cathodic catalysts for various types of LCBs, including aprotic, photo-assisted, and all-solid-state LCBs, offering insights and suggestions to advance their research and development.
Recent advances in high-performance lithium-rich manganese-based materials for solid-state lithium batteries
Authors: Gao Keke , Sun Chunwen , Wang Zelin
Published: August 2024

The applications of high-performance LRMs in ASSBs can effectively overcome the low energy density and poor safety in the liquid batteries. Significant progresses are used to address challenges and promote the practical application of LRMs in ASSBs.
Catalytic enantioselective synthesis of cyclopropyl α-amino carboxylates and phosphonates
Authors: Beucher Hélène , Alahyen Ismail , Talbot Alex , Poisson Thomas , Jubault Philippe
Published: August 2024

Herein, the catalytic asymmetric synthesis of tetra-substituted cyclopropyl α-amino carboxylates and cyclopropyl α-amino phosphonates is reported.
A nitrogen-doped bowl-shaped molecule containing a central heptagonal ring
Authors: Liu Tian , Wang Weifan , Zhang Gang
Published: August 2024

A nitrogen-doped heptagon-centered molecular bowl that can be viewed as a fragment mapped from a fullerene violating the isolated pentagon rule was synthesized and characterized.
Self-correcting mismatches in metastable hydrogen-bonded organic frameworks with an 11-fold interpenetrated array
Authors: Xia Guomin , Zhou Chunlei , Xiao Xingliang , Yang Yang , Yu Fuqing , Wang Hongming
Published: August 2024

SCXRD data reveal a nanoconfinement isomerization in 11-fold interpenetrated NCU-HOFs, resulting in highly robust structures with permanent porosity, contracted cavities for selective adsorption, and efficient fluorescent sensing of C2H4 gas.
Photoinduced Co/Ni-cocatalyzed Markovnikov hydroarylation of unactivated olefins with aryl bromides
Authors: Liu Hong-Chao , Xu Xin-Yu , Tang Siyuan , Bao Jiawei , Wang Yu-Zhao , Chen Yiliang , Han Xinya , Liang Yong-Min , Zhang Kui
Published: August 2024

A novel photoinduced Co/Ni-cocatalyzed Markovnikov hydroarylation of unactivated alkenes with aryl bromides by using proton as a hydrogen source has been developed for the first time.
Trityl isocyanide as a general reagent for visible light mediated photoredox-catalyzed cyanations
Authors: Quirós Irene , Martín María , Pérez-Sánchez Carla , Rigotti Thomas , Tortosa Mariola
Published: August 2024

Bench-stable trityl isocyanide enables the photoredox catalytic cyanation of carboxylic acids, alcohols and alkyl halides.
Initiating a composite membrane with a localized high iodine concentration layer based on adduct chemistry to enable highly reversible zinc–iodine flow batteries
Authors: Hu Yichan , Hu Tao , Zhang Yuanwei , Huang Haichao , Pei Yixian , Yang Yihan , Wu Yudong , Hu Haibo , Liang Guojin , Cheng Hui-Ming
Published: August 2024

A cost-effective and high-performance composite membrane is developed by leveraging a localized high iodine concentration layer based on the adducts chemistry, where polyiodide shuttling can be suppressed with improved coulombic/energy efficiency.
Prospects of ruthenate-based electrodes in metal-ion batteries
Authors: Majid Abdul , Khadim Bazgha , Alkhedher Mohammad , Bulut Niyazi
Published: August 2024

Advancements in energy storage technology have led to the exploration of novel functional materials that have been at the heart of materials science, especially in this century.
Band engineering in iron and silver co-doped double perovskite nanocrystals for selective photocatalytic CO2 reduction
Authors: Ahmad Razi , Zhang Yu , Navrátil Jan , Błoński Piotr , Zdražil Lukáš , Kalytchuk Sergii , Naldoni Alberto , Rogach Andrey L. , Otyepka Michal , Zboril Radek , Kment Štěpán
Published: August 2024

We report iron and silver co-doped Cs2NaInCl6 double perovskite nanocrystals which resulted precise tuning of electronic band structure. The synthesized nanocrystals were utilized for selective photocatalytic CO2 reduction into methane.
Graphene acid-enhanced interfacial layers with high Zn2+ ion selectivity and desolvation capability for corrosion-resistant Zn-metal anodes
Authors: Xia Kailai , Li Liuyan , Qiu Yanbin , Weng Jianqiang , Shen Shengtao , Chen Meixin , Zhuang Yuhang , Wen Yeye , Yang Chengkai , Liu Zheyuan , Wu Mingmao , Zou Zhigang
Published: August 2024

A Zn anode artificial interface capable of accelerating Zn2+ transfer/transport while achieving uniform and promoted Zn nucleation, ultimately resulting in stable and corrosion-free Zn anodes.
Highly dispersed platinum and phosphomolybdic acid (PMo) on the UiO-66 metal–organic framework (MOF) for highly efficient and selective hydrogenation of nitroaromatics
Authors: Chen Kai , Liu Qingqing , Qiu Zhiying , Zhang Huan , Gong Ning , Zhu Lihua
Published: August 2024

Pt-PMo@UiO-66 (0.32 wt% Pt) shows the highest catalytic activity and selectivity to one –NO2 hydrogenation in nitroarene hydrogenation due to its novel structure and synergism.
Selective electroreduction of CO2 into CO over Ag and Cu decorated carbon nanoflakes
Authors: Faraz Ahmad , Iqbal Waheed , Gul Shayan , Kanodarwala Fehmida K. , Zafar Muhammad Nadeem , Xu Guobao , Nadeem Muhammad Arif
Published: August 2024

The electrocatalytic CO2 reduction reaction (eCO2RR) has the potential to effectively cut carbon emission.
Automatic Speech Recognition in Primary Progressive Apraxia of Speech
Authors: Tetzloff Katerina A. , Wiepert Daniela , Botha Hugo , Duffy Joseph R. , Clark Heather M. , Whitwell Jennifer L. , Josephs Keith A. , Utianski Rene L.
Published: August 2024

Introduction:

Transcribing disordered speech can be useful when diagnosing motor speech disorders such as primary progressive apraxia of speech (PPAOS), who have sound additions, deletions, and substitutions, or distortions and/or slow, segmented speech. Since transcribing speech can be a laborious process and requires an experienced listener, using automatic speech recognition (ASR) systems for diagnosis and treatment monitoring is appealing. This study evaluated the efficacy of a readily available ASR system (wav2vec 2.0) in transcribing speech of PPAOS patients to determine if the word error rate (WER) output by the ASR can differentiate between healthy speech and PPAOS and/or among its subtypes, whether WER correlates with AOS severity, and how the ASR's errors compare to those noted in manual transcriptions.

Method:

Forty-five patients with PPAOS and 22 healthy controls were recorded repeating 13 words, 3 times each, which were transcribed manually and using wav2vec 2.0. The WER and phonetic and prosodic speech errors were compared between groups, and ASR results were compared against manual transcriptions.

Results:

Mean overall WER was 0.88 for patients and 0.33 for controls. WER significantly correlated with AOS severity and accurately distinguished between patients and controls but not between AOS subtypes. The phonetic and prosodic errors from the ASR transcriptions were also unable to distinguish between subtypes, whereas errors calculated from human transcriptions were. There was poor agreement in the number of phonetic and prosodic errors between the ASR and human transcriptions.

Conclusions:

This study demonstrates that ASR can be useful in differentiating healthy from disordered speech and evaluating PPAOS severity but does not distinguish PPAOS subtypes. ASR transcriptions showed weak agreement with human transcriptions; thus, ASR may be a useful tool for the transcription of speech in PPAOS, but the research questions posed must be carefully considered within the context of its limitations.

Supplemental Material:

https://doi.org/10.23641/asha.26359417
Precise Fourier parameters of Cepheid radial velocity curves: Towards refining the Hertzsprung progression models
Authors: Hocdé V. , Moskalik P. , Gorynya N. A. , Smolec R. , Rathour R. Singh , Ziółkowska O.
Published: August 2024

Context. Radial velocity (RV) curves of Classical Cepheids allow precise determination of the resonant periods, which in turn help to constrain fundamental parameters of these stars. The RV curves of Cepheids are also useful for identifying their pulsation modes and for distance determination using the parallax-of-pulsation method.

Aims. The primary goal of this paper is to derive precise Fourier parameters of the RV curves for fundamental and first-overtone Galactic Cepheids. Our secondary objectives are then to analyze the progression of the Fourier parameters up to the seventh harmonic, and to propose an identification of the pulsation modes of the stars.

Methods. For each star, we carefully selected RV measurements available in the literature that yield the highest precision of Fourier parameters according to the procedure that follows. We performed a Fourier decomposition of the RV curves using the unweighted least-square method and the standard deviation of the fit was used to derive the uncertainty on the Fourier parameters. We corrected for zero-point differences between datasets and RV modulations caused by binary motion.

Results. With this study we have more than doubled the number of Cepheids with published RV curve Fourier parameters and with their uncertainty properly estimated. Our sample includes 178 fundamental-mode and 33 first-overtone pulsators, as well as 7 additional Cepheids whose pulsation mode is uncertain or undetermined according to our criteria. For the fundamental-mode Cepheids, the precision of the obtained low-order Fourier phases and amplitudes is about seven times and 25% better, respectively, as compared to the precision achieved in previously published Fourier parameter surveys. With highly accurate RV Fourier phases ϕ21, we are able to firmly identify V495 Cyg as a new first-overtone Cepheid and we confirm the first-overtone nature of several other stars. In particular, α UMi should be firmly classified as a first-overtone pulsator. In three objects (VY Per, AQ Pup, and QZ Nor), we find significant γ-velocity variations, which for the first two objects (and possibly for QZ Nor as well) can be attributed to the spectroscopic binarity of these stars. Finally, the analysis of the fundamental mode Fourier parameters up to seventh order reveals tight progression of Fourier phases for all pulsation periods.

Conclusions. We provide new precise Fourier parameters of Cepheid RV curves determined from RV measurements available in the literature together with unpublished data. The pulsation period coverage and the precision obtained, in particular for Fourier phase ϕ21, will be useful for studying the dynamics of Cepheid pulsations with the help of hydrodynamical models. Further RV measurements from modern high-resolution spectroscopic instruments will be important to improve these results.
Searching for magnetic fields in featureless white dwarfs with the DIPOL-UF polarimeter at the Nordic Optical Telescope
Authors: Berdyugin A. , Landstreet J. D. , Bagnulo S. , Piirola V. , Berdyugina S. V.
Published: August 2024

About 20% of the white dwarfs possess a magnetic field that may be detected by the splitting and/or polarization of their spectral lines. As they cool, the effective temperatures of the white dwarfs become so low that no spectral lines can be seen in the visible wavelength range. If their atmospheres are not polluted by the debris of a planetary system, these cool white dwarfs have featureless optical spectra. Until quite recently, very little was known about the incidence of magnetic fields in these objects. However, when observed with polarimetric techniques, a significant number of featureless white dwarfs reveal strong magnetic fields in their optical continuum spectra. Measuring the occurrence rate and strength of magnetic fields in old white dwarfs may help us to understand how these fields are generated and evolve. We report the results of an ongoing survey of cool white dwarfs with the high-precision broad-band polarimeter DIPOL-UF, which is deployed at the Nordic Optical Telescope on La Palma, Spain. This survey has led to the firm discovery of 13 new cool magnetic white dwarfs in the solar neighborhood so far, including six new detections that we report in this paper.
Climate change in hell: Long-term variation in transits of the evaporating planet K2-22b
Authors: Gaidos E. , Parviainen H. , Esparza-Borges E. , Fukui A. , Isogai K. , Kawauchi K. , de Leon J. , Mori M. , Murgas F. , Narita N. , Palle E. , Watanabe N.
Published: August 2024

Context. Rocky planets on ultra-short period orbits can have surface magma oceans and rock-vapour atmospheres in which dust can condense. Observations of that dust can inform us about the composition and surface conditions on these objects.

Aims. We constrained the properties and long-term (decade) behaviour of the transiting dust cloud from the evaporating planet K2-22b.

Methods.We observed K2-22b around 40 predicted transits with MuSCAT ground-based multi-optical channel imagers, and complemented these data with long-term monitoring by the ground-based ATLAS (2018-2024) and space-based TESS (2021–2023) surveys.

Results. We detected signals during 7 transits, none of which showed significant wavelength dependence. The expected number of MuSCAT-detected transits is ≥22, indicating a decline in mean transit depth since the K2 discovery observations in 2014.

Conclusions. The lack of a significant wavelength dependence indicates that dust grains are large or the cloud is optically thick. Long-term trends of depth could be due to a magnetic cycle on the host star or to overturn of the planet’s dayside surface magma ocean. The possibility that K2-22b is disappearing altogether is ruled out by the stability of the transit ephemeris against non-gravitational forces, which constrains the mass to be at least comparable to Ceres.
Syndrome du canal étroit du rachis thoracolombaire chez un chat
Authors: Hassoun Roy , Bardet Jean-François
Published: August 2024

Cet article décrit une myélopathie compressive thoracolombaire congénitale très rare et jamais décrite dans l’espèce féline. Cette maladie est rarement décrite toutes espèces confondues, seuls des cas sont répertoriés chez un Bouledogue Anglais, un Basset Hound, des Bergers de Shiloh ainsi que chez deux jeunes chevaux.
Il s'agit d'une dysplasie hypertrophique des processus articulaires et des pédicules du rachis thoracolombaire entraînant une compression médullaire visible à l’examen tomodensitométrique.
Plusieurs signes cliniques de compression médullaire sont décrits.
Les lésions médullaires présentes dans ce cas clinique se situent entre les vertèbres T11 et L4 entraînant une atteinte des membres pelviens. Celle-ci se traduit par une incoordination, ainsi qu’une ataxie compatible avec une atteinte moto neurone centrale. Un traitement chirurgical par laminectomie et exérèse des facettes articulaires sur toute la longueur est réalisé et permet une amélioration clinique. Nous décrivons dans cet article l’évolution et le suivi de ce cas.
The Role of Electroencephalography in Children with Acute Altered Mental Status of Unknown Etiology: A Prospective Study
Authors: Chiarello Daniela , Perrone Annalisa , Ricci Emilia , Ferrera Giulia , Duranti Francesca , Bonetti Silvia , Marchiani Valentina , Fetta Anna , Lanari Marcello , Cordelli Duccio Maria
Published: August 2024

Introduction Acute altered mental status (AAMS) is often a challenge for clinicians, since the underlying etiologies cannot always easily be inferred based on the patient's clinical presentation, medical history, or early examinations. The aim of this study is to evaluate the role of electroencephalogram (EEG) as a diagnostic tool in AAMS of unknown etiology in children.

Materials and Methods We conducted a prospective study involving EEG assessments on children presenting with AAMS between May 2017 and October 2019. Inclusion criteria were age 1 month to 18 years and acute (<1 week) and persistent (>5 minutes) altered mental status. Patients with a known etiology of AAMS were excluded. A literature review was also performed.

Results Twenty patients (median age: 7.7 years, range: 0.5–15.4) were enrolled. EEG contributed to the diagnosis in 14/20 cases, and was classified as diagnostic in 9/20 and informative in 5/20. Specifically, EEG was able to identify nonconvulsive status epilepticus (NCSE) in five children and psychogenic events in four. EEG proved to be a poorly informative diagnostic tool at AAMS onset in six children; however, in five of them, it proved useful during follow-up.

Conclusions Limited data exist regarding the role of EEG in children with AAMS of unknown etiology. In our population, EEG proved to be valuable tool, and was especially useful in the prompt identification of NCSE and psychogenic events.
Case–Control and Cohort Studies in Homeopathy: Part 4 of the Research Method Series
Authors: Dutta Abhijit
Published: August 2024

Case–control and cohort studies are fundamental epidemiological research designs utilized to investigate the relationship between exposures and outcomes in medical research. This paper provides a comparative analysis of these two study designs, focusing on their respective strengths, applications, and implications for understanding disease etiology, progression, and intervention effectiveness. Case–control studies offer a retrospective lens, enabling researchers to assess the impact of exposures on disease development by comparing individuals with a particular outcome (cases) to those without (controls). Through meticulous selection and analysis, case–control studies unveil potential risk factors and causal relationships, particularly beneficial for investigating rare diseases or long latency periods. Conversely, cohort studies adopt a prospective approach, following a group of individuals over time to evaluate the incidence of outcomes in relation to exposures. This design facilitates the assessment of cumulative exposure effects, disease progression, and intervention efficacy, providing valuable insights into the natural history of diseases. In the context of homeopathy, both the study designs may be utilized for the evaluation of long-term treatment effects, disease progression, and patient satisfaction, shedding light on the holistic nature of homeopathic care. By embracing rigorous methodologies and leveraging the strengths of both study designs, researchers in homeopathy can advance evidence-based practice, enhancing our understanding of homeopathic principles and their practical implications in clinical settings.
Pd-Catalyzed Asymmetric Allylic Substitution Cascade via Desymmetrization for the Construction of Chiral Polyheterocycles
Authors: Kou Xuezhen , Xu Yongjin , Dong Siqi , Liu Hui , Liu Delong , Zhang Wanbin
Published: August 2024

Chiral polyheterocycles represent an important class of compounds because of their prevalence in bioactive natural products and chiral drugs. Pd-catalyzed allylic substitution is a powerful synthetic tool for forming C–C and C–X bonds (X = N, O, S, etc.). Naturally, asymmetric cascade reactions that utilize allylic substitution are undoubtedly efficient pathways to construct heterocycles. In this article, we reviewed the Pd-catalyzed asymmetric allylic substitution cascade via the desymmetrization of meso-diol diesters of cycloolefins, for the construction of chiral polyheterocycles and their derivatives.
Impact of Dietary Counseling on Nutritional requirements and Mitigating Noncompliance behavior in Hemodialysis Patients: A Pilot Study
Authors: Fernandes Sarita Telma , Dsilva Fatima
Published: August 2024

Introduction Hemodialysis is the most sought-after treatment modality in patients with end-stage renal disease. The success of hemodialysis depends on the patient's adherence to diet and fluid restrictions to a great extent. Nutritional health is a critical consideration, especially for hemodialysis patients. Nutritional education and counseling for renal disease patients significantly preserve renal function and overall well-being.

Methods Quantitative research approach with a quasi-experimental crossover design to determine the effectiveness of dietary counseling on the nutritional requirement and noncompliance behavior of patients undergoing hemodialysis conducted at Mangala Kidney Hospital, Mangalore, Karnataka, India.

Results The mean age among the participants was 46.07 + 9.67 years. Nearly half of the subjects, 11 (39.29%), had undergone dialysis for 1 to 5 years. Twenty-six (96.3%) had noncompliance behavior toward diet and fluid. Based on biochemical parameters, 20 (74.07%) were classified as low-risk noncompliance and 7 (25.92%) high-risk noncompliance behavior. A paired t-test showed that there is a significant difference in knowledge of nutritional requirements, t (26) = 6.30, p ≤ 0.001 at 5% level of significance, and noncompliance among the participants before and after the dietary counseling program as t (26) = –5.41, p ≤ 0.001 at 5% level of significance.

Conclusion Implementing nurse-led counseling for hemodialysis patients can improve biochemical parameters and enhance understanding of dietary and fluid restrictions, positively impacting laboratory indicators.
Risk perception of SMEs: strategic risks, family-related risks, external risks
Authors: Glowka Gundula , Hule Richard , Zehrer Anita
Published: August 2024

While risk perception is essential in understanding risk-taking behavior, the risk perception of Small- and Medium-sized Enterprises (SMEs) remains widely unexplored. Analyzing the current business situation of about 1000 German companies, we present stylized facts on the perception of risks. Our first result is that five out of twelve risks are dominantly perceived. The second result is a classification of all possible 4096 risk profiles into eight classes of ideal types of risk perception. Finally, we investigate which factors determine the probability of perceived risks using information on size, industry sector, and business situation of companies, together with data on their equity and family firm status. We use logistic regressions to investigate their impact. Data show that a good business situation lowers the probability of perceiving some of the strategic risks. We strongly argue to focus more strongly on risk perception for creating a better understanding of how SMEs take risks and manage uncertainty.
A gas spark switch electrode impact pressure test platform
Authors: Luo Cheng , Zhang Yongmin , Lu Yong , Zhang Shaojie , Wang Pengfei , Wang Haodong , Liu Zhi
Published: August 2024

The discharge arc of a high-current gas spark switch has a strong mechanical effect on the electrode and adjacent objects. The measurement of this mechanical effect on the electrode plays a very important role in switch design and the theoretical study of spark discharge. However, in traditional stress measurement systems, the spatial electromagnetic interference caused by the discharge and the high electrode voltage affects the measurement accuracy and can even damage the experimental instrument. In this paper, an electrode impact stress measurement system based on PVDF piezoelectric film is designed to measure the electrode stress under a strong spatial electromagnetic field and high voltage. The experimental results show that the system can measure the impact pressure of high-voltage and high-current gas spark switch electrodes. The starting time of the stress measurement waveform shows that the shock to the electrode is formed in the initial stage of current buildup. The measured results clearly show the high magnetic field force component in the electrode impact pressure waveform. The shock waveforms induced by different pulse capacitor values, breakdown voltages, and loads are examined. It is found that the shock stress waveforms applied to the electrodes are affected by the peak value of the current, dI/dt, and the discharge duration.
Wafer-scale Te thin film with high hole mobility and piezoelectric coefficients
Authors: Tai Xiaochi , Zhao Qianru , Chen Yan , Jiao Hanxue , Wu Shuaiqin , Zhou Dongjie , Huang Xinning , Xiong Ke , Lin Tie , Meng Xiangjian , Wang Xudong , Shen Hong , Chu Junhao , Wang Jianlu
Published: August 2024

p-type semiconductors are significant for integrated nanoelectronics. Tellurium (Te), a mono-elemental material, is a p-type semiconductor with high mobility. Its outstanding performance renders it widely applicable in the fields of electronics and optoelectronics. However, the wafer-scale fabrication of Te thin films is challenging. In this study, we reported an ion-bean sputtered Te thin film and investigated the effects of annealing temperatures. Annealing-induced crystallization kinetics were assessed through Raman spectroscopy, x-ray diffraction, and atomic force microscopy. After annealing, the film's conductivity increased from 10−5 to 10−4 S and mobility from 18 to 53 cm2 V−1 s−1. Dual AC resonance tracking switching spectroscopy piezoelectric force microscopy is used to investigate piezo/ferroelectric properties. The coercive voltages are −2 and 4 V respectively, and the effective piezoelectric coefficient (d33) is 40 pm/V. Butterfly and phase-switching loops demonstrate its possible ferroelectricity. The Te thin film has potential applications in optoelectronics, nonvolatile memory devices, and neuromorphic computation.
An improved cubature Kalman filter state prediction method based on the design of active denial tracking system
Authors: Sun Zongzheng , Niu Xinjian , Jia Kai , Liu Jianwei , Liu Yinghui
Published: August 2024

In this paper, an improved CKF (Cubature Kalman Filter) target tracking method is adopted to solve the tracking and pointing problem in the field of the Active Denial System. The math model of the system is built and the precision requirement is analyzed. The improved CKF method is input as the feedforward compensation for system control to improve the system tracking performance. In the process of the iterative CKF algorithm, nonlinear means are used. The method makes full use of measurement information and estimates the target velocity acceleration model parameters through the neural network, which is used as the input of the CKF to modify the process parameters of CKF and improve the state estimation accuracy. At the same time, the limited lower bound method is used to ensure that the gain reaches the lower bound bottom line of the precision demand, so that it does not tend to zero with time, so as to avoid affecting its rapid response ability during maneuvering and so that the prediction error is also controlled within the range of the precision demand. The simulation and experimental results show the superiority of the method and make the system fully meet the design requirements.
Generation of inflow turbulence using an improved synthetic eddy method
Authors: Long Wenxiao , Xiong Dapeng , Wang Hongbo , Sun Mingbo , Chen Huifeng , Li Wenming , Yang Yixin
Published: August 2024

The generation of turbulent inflow conditions is a key issue in large eddy simulation (LES) or direct numerical simulation (DNS). In this paper, an improved synthetic eddy method (SEM) is proposed to generate inflow turbulence for LES and DNS. The improvements about SEM focus on the eddy radius and eddy distributions. First, the eddy radius is improved to reduce the nonphysical vortex structure on the wall caused by overestimation of the radius. Second, a sampling method using Gaussian distribution is proposed to improve the distribution of eddies, which accurately captures the randomness of turbulent structure size and is close to the actual flow field. The improved method is applied to the direct numerical simulation of the supersonic turbulent boundary layer at Mach 2.7 and the 24° compression ramp. Results indicate that the predictions yielded by the improved method are in good agreement with both DNS and experimental data. Compared to the original method, the improved method exhibits a more rapid recovery of the friction coefficient and effectively shortens the development distances. The improved SEM has enhanced the efficiency and accuracy of generating inlet turbulence, which can provide inlet turbulence boundary conditions for LES and DNS.
Gyro fireworks algorithm: A new metaheuristic algorithm
Authors: Wang Xiaowei
Published: August 2024

In this paper, a novel Gyro Fireworks Algorithm (GFA) is proposed by simulating the behaviors of gyro fireworks during the display process, which adopts a framework of multi-stage and multiple search strategies. At the beginning of the iteration, the gyro fireworks are full of gunpowder; they move via Lévy flight and spiral rotation, and the sprayed sparks are widely distributed and more balanced, which is an effective global exploration method. In the later iteration stages, due to the consumption of gunpowder, the gyro fireworks gradually undergo aggregation and contraction of spiral rotation, which is conducive to the search group to exploit the local area near the global optimal position. The GFA divides the iterative process into four phases, and each phase adopts a different search strategy, in order to enhance the diversity of the search of the population and to balance the exploration capability of the gyro fireworks search group in the global space and the exploitation of the local space. In order to verify the performance of the GFA, it is compared with the latest algorithms, such as the dandelion optimizer, Harris Hawks Optimization (HHO) algorithm, gray wolf optimizer, slime mold algorithm, whale optimization algorithm, artificial rabbits optimization, in 33 test functions. The experimental results show that the GFA obtains the optimal solution for all algorithms on 76% of the functions, while the second-placed HHO algorithm obtains the optimal solution for all algorithms on only 21% of the functions. Meanwhile, the GFA has an average ranking of 1.8 on the CEC2014 benchmark set and 1.4 on the CEC2019 benchmark set. It verifies that the GFA proposed in this paper has better convergence performance and better robustness than the competing algorithms. Moreover, experiments on challenging engineering optimization problems confirm the superior performance of the GFA over alternative algorithms.
Modeling of the electronic excited states in high-temperature flows
Authors: Civrais C. H. B. , Pfeiffer M. , White C. , Steijl R.
Published: August 2024

This article introduces a novel model for describing the electronic excited states in the direct simulation Monte Carlo (DSMC) technique. The model involves the coupling the vibrational and electronic modes of molecular species, enabling each electronic excited state to excite its unique vibrational quantum levels. Numerical techniques are developed for equilibrium and post-collision sampling, as well as for measuring the internal temperature. The DSMC results demonstrate excellent agreement with theoretical predictions, providing verification of the successful implementation in a DSMC solver. For important thermophysical properties of molecular oxygen, such as the specific heat capacity, it is shown that the new model provides a better prediction than a compilation of past studies in comparison to the standard uncoupled approach in DSMC. The model is then applied to simulate a canonical nonreactive oxygen hypersonic flow past a cylindrical body. The population distribution of electronic excited states exhibit significant deviation from the standard approach typically used in the coupling between DSMC and radiation transport solvers.
Artifacts-free lensless on-chip tomography empowered by three-dimensional deconvolution
Authors: Zhou Yunhong , Yan Gongzhi , Guo Weixi , Yang Yuting , Guan Xinping
Published: August 2024

A lensless holographic microscope based on in-line holograms and optical diffraction tomography is an ideal imaging system for label-free 3D biological samples and can achieve large-volume imaging with single-cell resolution in a convenient way. However, due to the phase information loss and the missing cone problem, the imaging quality is significantly degraded by the reconstructed artifacts of twin images and out-of-focus images, which severely hinders the identification and interpretation of the objects. We propose an artifacts-free lensless on-chip tomography certified by three-dimensional deconvolution, which facilitates the extraction of real object morphology through straightforward yet effective computation. Initially, a globally valid systemic point spread function (PSF) is generated by simulating the imaging output of an ideal point light source positioned at the origin of the object space coordinate. Subsequently, an iterative three-dimensional deconvolution process is applied to the primitive imaging outcome of the lensless on-chip tomography using this PSF. Through rapid iterations, the optimized imaging result is swiftly obtained. Both the simulated and experimental results indicate that the artifacts-free lensless on-chip tomography can effectively circumvent the reconstructed artifacts and retrieve the real object morphology, which is critical for detailed observation and further quantitative analysis. In addition, we anticipate that the proposed approach has the potential to be transferred to other 3D imaging systems in systemic artifacts removal after corresponding modifications.
H3K14ac facilitates the reinstallation of constitutive heterochromatin in
Drosophila
early embryos by engaging Eggless/SetDB1
Authors: Tang Ruijun , Zhou Mengqi , Chen Yuwei , Jiang Zhenghui , Fan Xunan , Zhang Jingheng , Dong Aiping , Lv Lu , Mao Song , Chen Fang , Gao Guanjun , Min Jinrong , Liu Ke , Yuan Kai
Published: August 2024

Constitutive heterochromatin, a fundamental feature of eukaryotic nucleus essential for transposon silencing and genome stability, is rebuilt on various types of repetitive DNA in the zygotic genome during early embryogenesis. However, the molecular program underlying this process remains poorly understood. Here, we show that histone H3 lysine 14 acetylation (H3K14ac) is engaged in the reinstallation of constitutive heterochromatin in
Drosophila
early embryos. H3K14ac partially colocalizes with H3 lysine 9 trimethylation (H3K9me3) and its methyltransferase Eggless/SetDB1 around the mid-blastula transition. Concealing H3K14ac by either antibody injection or maternal knockdown of
Gcn5
diminishes Eggless/SetDB1 nuclear foci and reduces the deposition of H3K9me3. Structural analysis reveals that Eggless/SetDB1 recognizes H3K14ac via its tandem Tudor domains, and disrupting the binding interface causes defects in Eggless/SetDB1 distribution and derepression of a subset of transposons. Therefore, H3K14ac, a histone modification normally associated with active transcription, is a crucial component of the early embryonic machinery that introduces constitutive heterochromatic features to the newly formed zygotic genome.
Yeast Svf1 binds ceramides and contributes to sphingolipid metabolism at the ER cis-Golgi interface
Authors: Limar Sergej , Körner Carolin , Martínez-Montañés Fernando , Stancheva Viktoriya G. , Wolf Verena N. , Walter Stefan , Miller Elizabeth A. , Ejsing Christer S. , Galassi Vanesa Viviana , Fröhlich Florian
Published: August 2024

Ceramides are essential precursors of complex sphingolipids and act as potent signaling molecules. Ceramides are synthesized in the endoplasmic reticulum (ER) and receive their head-groups in the Golgi apparatus, yielding complex sphingolipids (SPs). Transport of ceramides between the ER and the Golgi is executed by the essential ceramide transport protein (CERT) in mammalian cells. However, yeast cells lack a CERT homolog, and the mechanism of ER to Golgi ceramide transport remains largely elusive. Here, we identified a role for yeast Svf1 in ceramide transport between the ER and the Golgi. Svf1 is dynamically targeted to membranes via an N-terminal amphipathic helix (AH). Svf1 binds ceramide via a hydrophobic binding pocket that is located in between two lipocalin domains. We showed that Svf1 membrane-targeting is important to maintain flux of ceramides into complex SPs. Together, our results show that Svf1 is a ceramide binding protein that contributes to sphingolipid metabolism at Golgi compartments.
EVs move messes, not messages, at the synapse
Authors: Bostelman Marina N. , Broihier Heather T.
Published: August 2024

Extracellular vesicles are known for intercellular signaling roles but can also serve to simply dispose of unwanted cargoes. In this issue, Bostelman and Broihier discuss new work from Rodal and colleagues (https://doi.org/10.1083/jcb.202405025) that refutes prior work by showing that extracellular vesicles at Drosophila neuromuscular junctions are not required for signaling and instead likely serve a proteostasis role.
Chiral Pair Density Waves with Residual Fermi Arcs in RbV3Sb5
Authors: Yan Xiao-Yu , Deng Hanbin , Yang Tianyu , Liu Guowei , Song Wei , Miao Hu , Tu Zhijun , Lei Hechang , Wang Shuo , Lin Ben-Chuan , Qin Hailang , Yin Jia-Xin
Published: August 2024

The chiral 2 × 2 charge order has been reported and confirmed in the kagome superconductor RbV3Sb5, while its interplay with superconductivity remains elusive owing to its lowest superconducting transition temperature T
C of about 0.85 K in the AV3Sb5 family (A = K, Rb, Cs) that severely challenges electronic spectroscopic probes. Here, utilizing dilution-refrigerator-based scanning tunneling microscopy down to 30 mK, we observe chiral 2 × 2 pair density waves with residual Fermi arcs in RbV3Sb5. We find a superconducting gap of 150 μeV with substantial residual in-gap states. The spatial distribution of this gap exhibits chiral 2 × 2 modulations, signaling a chiral pair density wave (PDW). Our quasi-particle interference imaging of the zero-energy residual states further reveals arc-like patterns. We discuss the relation of the gap modulations with the residual Fermi arcs under the space-momentum correspondence between PDW and Bogoliubov Fermi states.
Automated inspection approach for OCA particles in multi-layered cover glass of display module assembly
Authors: Miao Huisi , Yang Wucheng , Xu Weidong , Guo Yuhao , Zhao Hong , Huang Wei , Zhang Dongbo
Published: August 2024

CG (Cover Glass) is a critical component of electronic screens, and its manufacturing quality is closely relevant to the display effect. To satisfy the requirement of quality control, a machine vision system for real-time inspection of particles in the OCA (Optically Clear Adhesive) layer of CG is presented in this paper. With a brief description of the optical logic of particle imaging and the design of the vision system, our emphasis is put on the post-processing image analysis. To align particles regions in the CG under multi-mode imaging, a spatial alignment calibration algorithm is proposed with perspective distortion correction to calculate the triaxial offset. Then, a CLAHE+PM filtering is adopted to enhance the contrast of the particle. Furthermore, a Meanshift method combined with adaptive local thresholding is proposed to extract the contours of tiny particles. Finally, to distinguish between multiple layers of particles in the CG and detect OCA particles, a combination of fast background reconstruction and Averaged Stochastic Gradient Descent-Support Vector Machine is used. According to in-line experiments and tests, our system can find out a majority of the OCA particles with a PR
(over-detection rate) of 1.31% and a PM
(miss detection rate) of 0.33% for over 10 000 CG samples.
EDASNet: efficient dynamic adaptive-scale network for infrared pedestrian detection
Authors: Liu Yang , Zhang Ming , Fan Fei , Yu Dahua , Li Jianjun
Published: August 2024

Infrared images are widely utilized due to their exceptional anti-interference capabilities. However, challenges such as low resolution and an absence of detailed texture can impede the effective recognition of multi-scale target information, particularly for small targets. To address these issues, we introduce a multi-scale detection framework named efficient dynamic adaptive-scale network (EDASNet), which focuses on enhancing the feature extraction of small objects while ensuring efficient detection of multi-scale. Firstly, we design a lightweight dynamic enhance network as the backbone for feature extraction. It mainly includes a lightweight adaptive-weight downsampling module and a dynamic enhancement convolution module. In addition, a multi-scale aggregation feature pyramid network is proposed, which improves the perception effect of small objects through a multi-scale convolution module. Then, the Repulsion Loss term was introduced based on CIOU to effectively solve the missed detection problem caused by target overlap. Finally, the dynamic head was used as the network detection head, and through the superposition of dynamic convolution and multiple attention, the network was able to accurately realize multi-scale object detection. Comprehensive experiments show that EDASNet outperforms existing efficient models and achieves a good trade-off between speed and accuracy.
Data-driven inverse design of the perforated auxetic phononic crystals for elastic wave manipulation
Authors: Liu Hongyuan , Gao Yating , Lei Yongpeng , Wang Hui , Dong Qinxi
Published: August 2024

In addition to the distinctive features of tunable Poisson’s ratio from positive to negative and low stress concentration, the perforated auxetic metamaterials by peanut-shaped cuts have exhibited excellent phononic crystal (PNC) behavior as well for elastic wave manipulation. Thus they have attracted much attention in vibration suppression for dynamic applications. However, traditional structural designs of the auxetic PNCs considerably depend on designers’ experience or inspiration to fulfill the desired multi-objective bandgap properties through extensive trial and error. Hence, developing a more efficient and robust inverse design method remains challenging to accelerate the creation of auxetic PNCs and improve their performance. To shorten this gap, a new machine learning (ML) framework consisting of double back propagation neural network (BPNN) modules is developed in this work to produce desired configurations of the auxetic PNCs matching the customized bandgap. The first inverse BPNN module is trained to establish a logical mapping from the bandgap properties to the structural parameters, and then the second forward BPNN module is introduced to give the new property prediction by using the design configurations generated from the former. The error between the new predictions and the desired target properties is minimized through a limited number of iterations to produce the final optimal objective configurations. The results indicate that the perforated auxetic metamaterials behave relatively wide complete bandgap and the present ML model is effective in designing them with specific bandgaps within or beyond the given dataset. The study provides a powerful tool for designing and optimizing the perforated auxetic metamaterials in dynamic environment.