bluuebunny/crossref_metadata_2025 huggingface dataset:
Coherence mapping to identify the intermediates of multi-channel dissociative ionization
Authors: Stamm Jacob , Kwon Sung , Sandhu Shawn , Sandhu Jesse , Levine Benjamin G. , Dantus Marcos
Published: May 2024

Identifying the short-lived intermediates and reaction mechanisms of multi-channel radical cation fragmentation processes remains a current and important challenge to understanding and predicting mass spectra. We find that coherent oscillations in the femtosecond time-dependent yields of several product ions following ultrafast strong-field ionization represent spectroscopic signatures that elucidate their mechanism of formation and identify the intermediate(s) they originate from. Experiments on endo-dicyclopentadiene show that vibrational frequencies from various intermediates are mapped onto their resulting products. Aided by ab initio methods, we identify the vibrational modes of both the cleaved and intact molecular ion intermediates. These results confirm stepwise and concerted fragmentation pathways of the dicyclopentadiene ion. This study highlights the power of tracking the femtosecond dynamics of all product ions simultaneously and sheds further light onto one of the fundamental reaction mechanisms in mass spectrometry, the retro-Diels Alder reaction.
Testing the predictive power of reverse screening to infer drug targets, with the help of machine learning
Authors: Daina Antoine , Zoete Vincent
Published: May 2024

Estimating protein targets of compounds based on the similarity principle—similar molecules are likely to show comparable bioactivity—is a long-standing strategy in drug research. Having previously quantified this principle, we present here a large-scale evaluation of its predictive power for inferring macromolecular targets by reverse screening an unprecedented vast external test set of more than 300,000 active small molecules against another bioactivity set of more than 500,000 compounds. We show that machine-learning can predict the correct targets, with the highest probability among 2069 proteins, for more than 51% of the external molecules. The strong enrichment thus obtained demonstrates its usefulness in supporting phenotypic screens, polypharmacology, or repurposing. Moreover, we quantified the impact of the bioactivity knowledge available for proteins in terms of number and diversity of actives. Finally, we advise that developers of such approaches follow an application-oriented benchmarking strategy and use large, high-quality, non-overlapping datasets as provided here.
Enzymatic synthesis of mono- and trifluorinated alanine enantiomers expands the scope of fluorine biocatalysis
Authors: Nieto-Domínguez Manuel , Sako Aboubakar , Enemark-Rasmussen Kasper , Gotfredsen Charlotte Held , Rago Daniela , Nikel Pablo I.
Published: May 2024

Fluorinated amino acids serve as an entry point for establishing new-to-Nature chemistries in biological systems, and novel methods are needed for the selective synthesis of these building blocks. In this study, we focused on the enzymatic synthesis of fluorinated alanine enantiomers to expand fluorine biocatalysis. The alanine dehydrogenase from Vibrio proteolyticus and the diaminopimelate dehydrogenase from Symbiobacterium thermophilum were selected for in vitro production of (R)-3-fluoroalanine and (S)-3-fluoroalanine, respectively, using 3-fluoropyruvate as the substrate. Additionally, we discovered that an alanine racemase from Streptomyces lavendulae, originally selected for setting an alternative enzymatic cascade leading to the production of these non-canonical amino acids, had an unprecedented catalytic efficiency in β-elimination of fluorine from the monosubstituted fluoroalanine. The in vitro enzymatic cascade based on the dehydrogenases of V. proteolyticus and S. thermophilum included a cofactor recycling system, whereby a formate dehydrogenase from Pseudomonas sp. 101 (either native or engineered) coupled formate oxidation to NAD(P)H formation. Under these conditions, the reaction yields for (R)-3-fluoroalanine and (S)-3-fluoroalanine reached >85% on the fluorinated substrate and proceeded with complete enantiomeric excess. The selected dehydrogenases also catalyzed the conversion of trifluoropyruvate into trifluorinated alanine as a first-case example of fluorine biocatalysis with amino acids carrying a trifluoromethyl group.
Stoichiometric control of electron mobility and 2D superconductivity at LaAlO3-SrTiO3 interfaces
Authors: Singh Gyanendra , Guzman Roger , Saïz Guilhem , Zhou Wu , Gazquez Jaume , Masoudinia Fereshteh , Winkler Dag , Claeson Tord , Fraxedas Jordi , Bergeal Nicolas , Herranz Gervasi , Kalaboukhov Alexei
Published: May 2024

SrTiO3-based conducting interfaces, which exhibit coexistence of gate-tunable 2D superconductivity and strong Rashba spin-orbit coupling (RSOC), are candidates to host topological superconductive phases. Yet, superconductivity is usually in the dirty limit, which tends to suppress nonconventional pairing and therefore challenges these expectations. Here we report on LaAlO3/SrTiO3 (LAO/STO) interfaces with large mobility and mean free paths comparable to the superconducting coherence length, approaching the clean limit for superconductivity. We further show that the carrier density, mobility, and formation of the superconducting condensate are controlled by the fine-tuning of La/Al chemical ratio in the LAO film. We find a region in the superconducting phase diagram where the critical temperature is not suppressed below the Lifshitz transition, at odds with previous experimental investigations. These findings point out the relevance of achieving a clean-limit regime to enhance the observation of unconventional pairing mechanisms in these systems.
Skin-interfacing wearable biosensors for smart health monitoring of infants and neonates
Authors: Zhou Lauren , Guess Matthew , Kim Ka Ram , Yeo Woon-Hong
Published: May 2024

Health monitoring of infant patients in intensive care can be especially strenuous for both the patient and their caregiver, as testing setups involve a tangle of electrodes, probes, and catheters that keep the patient bedridden. This has typically involved expensive and imposing machines, to track physiological metrics such as heart rate, respiration rate, temperature, blood oxygen saturation, blood pressure, and ion concentrations. However, in the past couple of decades, research advancements have propelled a world of soft, wearable, and non-invasive systems to supersede current practices. This paper summarizes the latest advancements in neonatal wearable systems and the different approaches to each branch of physiological monitoring, with an emphasis on smart skin-interfaced wearables. Weaknesses and shortfalls are also addressed, with some guidelines provided to help drive the further research needed.
Turbulent particle-gas feedback exacerbates the hazard impacts of pyroclastic density currents
Authors: Uhle Daniel H. , Lube Gert , Breard Eric C. P. , Meiburg Eckart , Dufek Josef , Ardo James , Jones Jim R. , Brosch Ermanno , Corna Lucas R. P. , Jenkins Susanna F.
Published: May 2024

Causing one-third of all volcanic fatalities, pyroclastic density currents create destruction far beyond our current scientific explanation. Opportunities to interrogate the mechanisms behind this hazard have long been desired, but pyroclastic density currents persistently defy internal observation. Here we show, through direct measurements of destruction-causing dynamic pressure in large-scale experiments, that pressure maxima exceed theoretical values used in hazard assessments by more than one order of magnitude. These distinct pressure excursions occur through the clustering of high-momentum particles at the peripheries of coherent turbulence structures. Particle loading modifies these eddies and generates repeated high-pressure loading impacts at the frequency of the turbulence structures. Collisions of particle clusters against stationary objects generate even higher dynamic pressures that account for up to 75% of the local flow energy. To prevent severe underestimation of damage intensities, these multiphase feedback processes must be considered in hazard models that aim to mitigate volcanic risk globally.
China’s ecological footprint via biomass import and consumption is increasing
Authors: Wang Shaojian , Fang Chuanglin , Chen Xiangjie , Liang Junyi , Liu Kangyao , Feng Kuishuang , Hubacek Klaus , Wang Jieyu
Published: May 2024

As China’s economic and population demands grow, the need for biomass imports rises, presenting challenges for sustainable development and global ecosystem protection. Here we examine China’s increasing influence on global ecosystems through its biomass product consumption and trade using the Human Appropriation of Net Primary Productivity framework, analyzing data from 2004 to 2017 with projections until 2050. In 2017, China was the world’s largest biomass consumer, consuming approximately 1.75 petagrams of carbon per year, projected to rise by 317.6% by 2050, highlighting China’s major role in global ecosystem stress. Our findings also show an increase in biomass imports from lower-middle-income and low-income countries between 2004 and 2017, and these imports are expected to continue increasing by 402.9% in 2050. The analysis reveals that domestic product demand and changes in foreign production efficiency are key drivers of this trend, suggesting the need for China to shift towards more efficient trade practices and support cleaner production methods internationally.
Density and strength variations in the mantle lithosphere affect the distribution of intraplate earthquakes
Authors: Bott Judith , Scheck-Wenderoth Magdalena , Kumar Ajay , Cacace Mauro , Noe Sebastian , Faleide Jan Inge
Published: May 2024

The distribution of earthquakes in stable intracontinental tectonic settings is typically far more diffuse than along plate boundaries and the causative mechanisms underlying some recognizable clustering are not understood. Here we show that seismicity in intraplate western and central Europe is largely limited to regions that exhibit a low-density layer in the uppermost lithospheric mantle and preferentially clustered above lateral gradients in upper mantle effective viscosity. The basis for these new insights into the thermal and density configuration of the upper mantle is provided by a shear-wave tomographic model. We propose that the spatial correlations between mantle low-density bodies and crustal seismicity reflect the importance of buoyancy forces within the mantle lithosphere. In addition, under the interaction of forces due to mantle gravitational instabilities, plate tectonics and postglacial rebound, the variably hot and strong mantle lithosphere responds by localized deformation which imposes differential loading on the overlying crust.
Aging clocks based on accumulating stochastic variation
Authors: Meyer David H. , Schumacher Björn
Published: May 2024

Aging clocks have provided one of the most important recent breakthroughs in the biology of aging, and may provide indicators for the effectiveness of interventions in the aging process and preventive treatments for age-related diseases. The reproducibility of accurate aging clocks has reinvigorated the debate on whether a programmed process underlies aging. Here we show that accumulating stochastic variation in purely simulated data is sufficient to build aging clocks, and that first-generation and second-generation aging clocks are compatible with the accumulation of stochastic variation in DNA methylation or transcriptomic data. We find that accumulating stochastic variation is sufficient to predict chronological and biological age, indicated by significant prediction differences in smoking, calorie restriction, heterochronic parabiosis and partial reprogramming. Although our simulations may not explicitly rule out a programmed aging process, our results suggest that stochastically accumulating changes in any set of data that have a ground state at age zero are sufficient for generating aging clocks.
Identification of the needs of individuals affected by COVID-19
Authors: Stanley Halina B. , Pereda-Campos Veronica , Mantel Marylou , Rouby Catherine , Daudé Christelle , Aguera Pierre-Emmanuel , Fornoni Lesly , Hummel Thomas , Weise Susanne , Mignot Coralie , Konstantinidis Iordanis , Garefis Konstantinos , Ferdenzi Camille , Pierron Denis , Bensafi Moustafa
Published: May 2024

Background

The optimal management of COVID-19 symptoms and their sequelae remains an important area of clinical research. Policy makers have little scientific data regarding the effects on the daily life of affected individuals and the identification of their needs. Such data are needed to inform effective care policy.

Methods

We studied 639 people with COVID-19 resident in France via an online questionnaire. They reported their symptoms, effects on daily life, and resulting needs, with particular focus on olfaction.

Results

The results indicate that a majority of participants viewed their symptoms as disabling, with symptoms affecting their physical and mental health, social and professional lives. 60% of the individuals reported having unmet medical, psychological and socio-professional support needs. Finally, affected individuals were concerned about the risk and invasiveness of possible treatments as shown by a preference for non-invasive intervention over surgery to cure anosmia.

Conclusions

It is important that policy makers take these needs into consideration in order to assist affected individuals to regain a normal quality of life.
Social environment-based opportunity costs dictate when people leave social interactions
Authors: Gabay Anthony S. , Pisauro Andrea , O’Nell Kathryn C. , Apps Matthew A. J.
Published: May 2024

There is an ever-increasing understanding of the cognitive mechanisms underlying how we process others’ behaviours during social interactions. However, little is known about how people decide when toleavean interaction. Are these decisions shaped by alternatives in the environment – the opportunity-costs of connecting to other people? Here, participants chose when to leave partners who treated them with varying degrees of fairness, and connect to others, in social environments with different opportunity-costs. Across four studies we find people leave partners more quickly when opportunity-costs are high, both the average fairness of people in the environment and the effort required to connect to another partner. People’s leaving times were accounted for by a fairness-adapted evidence accumulation model, and modulated by depression and loneliness scores. These findings demonstrate the computational processes underlying decisions to leave, and highlight atypical social time allocations as a marker of poor mental health.
Free-base amino acid-encoded microsystems for dual detection of narcotics and therapeutic antidote monitoring
Authors: Srivastava Sarvesh Kumar
Published: May 2024

Theranostics potential: Au nanocactuses as a novel SERS substrate and underlying polymeric Trp interface for drug release kinetics study.
Responsive ZIF-90 nanocomposite material: targeted delivery of 10-hydroxycamptothecine to enhance the therapeutic effect of colon cancer (HCT116) cells
Authors: Guo Ji-Chao , Deng Shi-Hui , Zhou Shu-Min , Zhou Xuan , Du Jiajia , Zhou Si-Han , Zhao Qi-Hua , Cai Zhong-Yan , Ren Xiaoxia , Xie Ming-jin
Published: May 2024

There is significant value in developing multifunctional drug delivery systems with high therapeutic efficiency for diagnosing and treating tumors.
Novel pH-sensitive gum ghatti-cl-poly(acrylic acid) composite hydrogel based on graphene oxide for metformin hydrochloride and sodium diclofenac combined drug-delivery systems
Authors: Dave Pragnesh N. , Macwan Pradip M.
Published: May 2024

The results showed that the mixtures of synthetic hydrogels might be utilised as potential agents for controlled drug delivery vehicles.
Green synthesis of cobalt ferrite from rotten passion fruit juice and application as an electrocatalyst for the hydrogen evolution reaction
Authors: Medang Rochelin Prosper , Lontio Fomekong Roussin , Nforna Edwin Akongnwi , Tedjieukeng Kamta Hypolite Mathias , Yonti Cédrik Ngnintedem , Tsobnang Patrice Kenfack , Lambi John Ngolui , Bitondo Dieudonné
Published: May 2024

Rotten passion fruits, which are highly available in many countries during some periods of the year, can be used to efficiently produce CoFe2O4 material with special structural and electrochemical characteristics for the hydrogen evolution reaction.
Quantitative assessment of daratumumab in serum via intact light chain measurement using liquid chromatography-high resolution mass spectrometry: a method suitable for therapeutic drug monitoring
Authors: Canil Giovanni , Miolo Gianmaria , Simula Mariapaola , Rupolo Maurizio , Steffan Agostino , Corona Giuseppe
Published: May 2024

Effective quantification of serum daratumumab monoclonal antibody for therapeutic drug monitoring using LC-HRMS based on light chain analysis.
A near-infrared (NIR) organic probe for rapid naked-eye detection of fluoride ions in aqueous medium
Authors: Richard Sathiaraj , Shabashini Arivalagan , Panja Sumit Kumar , Chandra Nandi Ganesh
Published: May 2024

A dihydroxy-substituted tricyanopyrroline-based near-infrared (NIR) colorimetric probe (TCP-34Hy) is developed for the effective detection of fluoride ions in aqueous medium in the presence of Ca2+ ions.
9-Step synthesis of (−)-larikaempferic acid methyl ester enabled by skeletal rearrangement
Authors: Rivera Mario E. , Li Lei , Kolisetti Aditya , Chi Nina , Dai Mingji
Published: May 2024

A 9-step synthesis of (−)-larikaempferic acid methyl ester is achieved via a skeletal rearrangement strategy and controlled transannular aldol reaction.
Iron-catalyzed benzylic C–H thiolation via photoinduced ligand-to-metal charge-transfer
Authors: Sun Kaiting , Sun Tianyi , Jiang Yuxin , Shi Jiayue , Sun Wenlu , Zheng Youyou , Wang Zhixuan , Li Ziyu , Lv Xiaoqing , Zhang Xingxian , Luo Fan , Liu Shihui
Published: May 2024

The protocol features operational simplicity, mild reaction conditions, and the use of FeCl3 as catalyst and thiols/disulfides as sulfur sources, which enables the transformation of diverse benzylic C–H bonds into C–S bonds with a high efficiency.
Molecular self-assembly of 1D linear and 2D T-shape polyiodide arrangements in two organic ammonium triiodide salts: supramolecular structures and density functional theory-based optical properties
Authors: Hamdouni Monia , Hrizi Chakib , Esghaier Mohsen Ouled Mohamed , Knorr Michael , Strohmann Carsten , Chaabouni Slaheddine
Published: May 2024

Schematic depiction of the σ MOs in the vicinity of the HOMO of I3−. The orbital distribution of HOMO-2 and LUMO for compounds 1 and 2 computed at the TD-DFT method.
The ameliorative mechanism of Lactiplantibacillus plantarum NJAU-01 against d-galactose induced oxidative stress: a hepatic proteomics and gut microbiota analysis
Authors: Jin Du-xin , Jia Chao-yang , Yang Bo , Wu Yue-hao , Chen Lei , Liu Rui , Wu Man-gang , Yu Hai , Ge Qing-feng
Published: May 2024

L. plantarum NJAU-01 could ameliorate hepatic oxidative damage in ICR mice induced by d-gal via modulating the gut microbiota composition and regulating the liver protein expression profile.
Multifunctional MgAl LDH/Zn-MOF S-scheme heterojunction: efficient hydrogen production, methyl red removal, and CO2 adsorption
Authors: Maseeh Ihsan , Anwar Farheen , Aroob Sadia , Javed Tariq , Bibi Ismat , Almasoudi Afaf , Raheel Ahmad , Javid Muhammad Arshad , Carabineiro Sónia A. C. , Taj Muhammad Babar
Published: May 2024

MgAl LDH/Zn-MOF S-scheme heterojunction exhibits superior photocatalytic activity for H2 evolution, methyl red dye removal and CO2 adsorption due to increased light absorption, high surface area, good stability and recyclability.
Hydrothermal synthesis of an MoS2/MnO2 nanocomposite: a unique 3D-nanoflower/1D-nanorod structure for high-performance energy storage applications
Authors: Islam Md. Roxy , Rahaman Mizanur , Billah Md. Muktadir , Islam Muhammad Rakibul
Published: May 2024

In this study, an MoS2/MnO2 nanocomposite electrode with a novel 3D nanoflower/1D nanorod architecture is effectively synthesized using a straightforward, cost-effective hydrothermal process.
Species-level identification of enterotype-specific microbial markers for colorectal cancer and adenoma
Authors: Güven Gülhan Ünzile , Nikerel Emrah , Çakır Tunahan , Erdoğan Sevilgen Fatih , Durmuş Saliha
Published: May 2024

Enterotype-based meta-analysis of fecal shotgun metagenomics reveals novel enterotype-specific microbial markers for non-invasive screening of colorectal cancer.
Al2O3 promoted mechanochemical nucleophilic aromatic substitution
Authors: Vaghi Luca , Palomba Eva , Papagni Antonio
Published: May 2024

An auxiliary mediated solventless mechanochemical methodology for the nucleophilic aromatic substitution of aryl fluorides by nitrogen nucleophiles without the aid of any base has been developed.
Frictional behavior of one-dimensional materials: an experimental perspective
Authors: Yibibulla Tursunay , Hou Lizhen , Mead James L. , Huang Han , Fatikow Sergej , Wang Shiliang
Published: May 2024

Experimental characterization techniques for the frictional properties of 1D materials were compiled and critically assessed. Key achievements were discussed, and future research focuses and directions were outlined.
Disubstituted thiourea as a suitable sulfur source in the gram-scale synthesis of yellow- and red-emitting CdTeS/CdxZn1−xS core/shell quantum dots
Authors: Loghina Liudmila , Houdek Jakub , Slang Stanislav , Frumarova Bozena , Cieslar Miroslav , Vlcek Miroslav
Published: May 2024

The advanced synthesis of highly photoluminescent CdTeS quantum dots was performed through their precursor ratio manipulation for the high-precision formation of CdTeS/CdxZn1−xS (x = 0.1, 0.2, and 0.3) core/shell 2 ML QDs.
Indium-based quantum dots trapped in solid-state matrices: a one-pot synthesis, thermoresponsive properties, and enhanced micropollutant removal
Authors: Ük Nida , Aykut Sümeyye , Jahangiri Hadi , Nar Ilgın , Ünlü Caner
Published: May 2024

Indium-based quantum dots are innovatively synthesized using a one-pot method by embedding them in insoluble oleic acid aggregates with controllable fluorescence and thermo-responsive properties, demonstrating high micropollutant removal efficiency.
A graphite/amorphous diamond coupled framework with high ORR and OER performance applied as a cathode catalyst in zinc–air batteries
Authors: Yin Yizhi , Ma Dandan , Liu Huize , Wang Guandong , Lin Chenfeng , Ma Jinfu
Published: May 2024

A B,N co-doped graphite/amorphous diamond coupling framework was designed to increase the amount of sp3 carbon inside the material, construct the sp2/sp3 carbon interface.
Criterion (Concurrent) Validity and Clinical Utility of the Tongueometer Device
Authors: Krekeler Brittany N. , Hopkins Anna , Tabangin Meredith E. , Altaye Mekibib , Roberts Rachel , Saadi Raneh , Martin-Harris Bonnie , Rogus-Pulia Nicole
Published: May 2024

Purpose:

Tongue manometry (i.e., tongue pressure measurement) is a commonly used assessment for patients with suspected oral-motor involvement in swallowing disorders. Availability of lingual manometry has changed in recent years, with the introduction of the Tongueometer device being a more affordable tongue manometry system. The purpose of this study was to test concurrent (criterion) validity of the Tongueometer compared to the current standard reference device, the Iowa Oral Performance Instrument (IOPI).

Method:

Adults without dysphagia were recruited for participation in this study. Standard lingual measurements (swallowing-related pressures, maximum isometric pressure [MIP], and maximum isometric endurance) were recorded, with the bulb anteriorly placed, with both devices, in a randomized order. The Bland–Altman method was used to determine concurrent (criterion) validity of these measurements compared to the clinical standard IOPI device. A recently available suggested corrective value by
Curtis et al. (2023)
was also applied, with comparisons made between devices both with and without the Curtis correction.

Results:

The final sample included 70 adult participants aged 20–89 years (
M
age
= 52.3 years). Measures with the Tongueometer device were significantly lower when compared with the same measures taken using the IOPI (
p
< .01) for all measures including MIP, endurance, and swallow pressures. The correction suggested by Curtis and colleagues did not ameliorate these differences.

Conclusions:

The Tongueometer lingual measurements were consistently lower compared to the IOPI. Clinical use of values taken with the Tongueometer device should be compared to normative data published for each specific device. Available features of each device (e.g., display, bulb texture, technology/application) should be considered when selecting which device to use with an individual patient.
Perceptions Around Vocal Health Among Group Fitness Instructors and Pilot Use of Group Fitness Instructor–Specific Voice Handicap Questionnaire
Authors: Dacey Sydney , Koppel Sari , Keltz Andrew , Livecchi Danielle , Kohli Nikita , Lerner Michael Z.
Published: May 2024

Purpose:

This study aimed to examine the vocal behaviors of group fitness instructors (GFIs), explore awareness among GFIs about voice-specialized health care, and assess the potential utility of a GFI-specific voice handicap questionnaire.

Method:

An anonymous 27-question survey was distributed digitally to GFIs. In addition to collecting demographic data and information about vocal behaviors and demands, the survey included a 10-question GFI-specific questionnaire (GFI-VHI-10) adapted from the Singing Voice Handicap Index-10.

Results:

Fifty-two GFIs participated in the study (75% female, 25% male) with a mean age of 44.6 years. Forty-six percent reported having a voice problem (VP) since entering the fitness industry. Of those 24 individuals, only four received treatment. There was a statistically significant difference in mean GFI-VHI-10 scores between the VP group (11.87) and the non-VP group (6.1), (
p
< .001). Of all respondents, 56% reported never or almost never wearing a microphone while instructing. When asked what they would do if they experienced a VP that lasted for longer than 2 weeks, only 9.6% would see a laryngologist, 23% would see an otolaryngologist, 31% would see their primary care provider, 11.5% were unsure, and 25% would ignore it and hope for spontaneous improvement.

Conclusions:

Although GFIs are at increased risk for vocal health challenges due to their occupational voice demands, their adherence to vocal health maintenance behaviors and awareness of voice-specialized health care may be limited. The GFI-VHI-10 is a promising tool in that it captured higher scores in the VP group than the non-VP group; however, further exploration is warranted.
A back‐to‐back coordination‐based learning scheme for deceiving reactive jammers in distributed networks
Authors: Du Yihang , Zhang Yu , Qian Pengzhi , He Panfeng , Wang Wei , Chen Yifei , Chen Yong
Published: May 2024

Reactive jammers select jamming strategies according to the users’ responses; thus, conventional anti‐jamming methods such as frequency hopping are inadequate to defeat the jamming attack. In this article, the authors propose a novel uncoupled deception scheme to trap the reactive jammer into attacking a decoy channel in distributed networks. Specifically, the authors design a multi‐functional network utility for every user to mislead the jammer with a minimum energy consumption while achieving the highest network throughput. Based on the network utility, the anti‐jamming problem is formulated as an exact potential game such that the existence of Nash equilibrium can be guaranteed theoretically. The authors further propose a back‐to‐back coordination‐based learning algorithm to reach the optimal channel selection and power adaption in a non‐cooperative way. To alleviate the lack of mutual information exchange, the back‐to‐back coordination mechanism derives all users to deceive the jammer by inferring others’ strategies based on a shared belief. Simulation results show that the proposed algorithm yields higher network throughput and efficiency‐cost ratio compared to the state‐of‐the‐art cooperative schemes.
Looking back to move forward: comparison of instructors’ and undergraduates’ retrospection on the effectiveness of online learning using the nine-outcome influencing factors
Authors: Su Yujie , Xu Xiaoshu , Zhang Yunfeng , Xu Xinyu , Hao Shanshan
Published: May 2024

This study delves into the retrospections of undergraduate students concerning their online learning experiences after the COVID-19 pandemic, using the nine key influencing factors: behavioral intention, instruction, engagement, interaction, motivation, self-efficacy, performance, satisfaction, and self-regulation. 46 Year 1 students from a comprehensive university in China were asked to maintain reflective diaries throughout an academic semester, providing first-person perspectives on the strengths and weaknesses of online learning. Meanwhile, 18 college teachers were interviewed with the same questions as the students. Using thematic analysis, the research identified 9 factors. The research revealed that instruction ranked highest among the 9 factors, followed by engagement, self-regulation, interaction, motivation, and others. Moreover, teachers and students had different attitudes toward instruction. Thirdly, teacher participants were different from student participants given self-efficacy and self-regulation due to their variant roles in online instruction. Lastly, the study reflected students were not independent learners, which explained why instruction ranked highest in their point of view. Findings offer valuable insights for educators, administrators, and policy-makers involved in higher education. Recommendations for future research include incorporating a more diverse sample, exploring relationships between the nine factors, and focusing on equipping students with skills for optimal online learning experiences.
Domestic violence against women during the COVID19 pandemic in Jordan: a systematic review
Authors: Alrawashdeh Maissa N. , Alsawalqa Rula Odeh , Aljbour Rami , Alnajdawi Ann , AlTwahya Fawzi Khalid
Published: May 2024

This study aimed to explore the forms and causes of domestic violence against women in Jordan during the COVID-19 pandemic through a systematic literature review. The review yielded eight articles published between April 2020 and November 2022 in the final sample, all of which met the inclusion criteria. The results revealed 11 forms of domestic violence against women in Jordan during and after the full and partial lockdowns due to the pandemic. Physical violence was the most prevalent form of domestic violence, followed by economic, psychological, emotional, verbal, and sexual forms, as well as control and humiliation, bullying, online abuse, harassment and neglect-related violence. The causes were a combination of economic, socio-cultural, and psychological factors emerging because of the pandemic and lockdowns (e.g., poverty, job loss, low wages, gender discrimination, double burden on women [monotonous roles, paid work], male dominance, reduced income, high cost of living). Additionally, effects of the pandemic included psychological, mental, and emotional negative consequences (e.g., anxiety, fear, stress, depression, loneliness, failure, status frustration). Individuals in Jordanian societies employed the norms, ideas, and values of the patriarchal culture to negatively adapt to the economic and psychological effects of the pandemic, which contributed to more domestic violence cases.
Brain-inspired learning in artificial neural networks: A review
Authors: Schmidgall Samuel , Ziaei Rojin , Achterberg Jascha , Kirsch Louis , Hajiseyedrazi S. Pardis , Eshraghian Jason
Published: May 2024

Artificial neural networks (ANNs) have emerged as an essential tool in machine learning, achieving remarkable success across diverse domains, including image and speech generation, game playing, and robotics. However, there exist fundamental differences between ANNs’ operating mechanisms and those of the biological brain, particularly concerning learning processes. This paper presents a comprehensive review of current brain-inspired learning representations in artificial neural networks. We investigate the integration of more biologically plausible mechanisms, such as synaptic plasticity, to improve these networks’ capabilities. Moreover, we delve into the potential advantages and challenges accompanying this approach. In this review, we pinpoint promising avenues for future research in this rapidly advancing field, which could bring us closer to understanding the essence of intelligence.
Thermal deflection in neutron scattering sample environments at Oak Ridge National Laboratory
Authors: Quirinale D. G. , Stevens E. , Zhang Y. , Mills R. A.
Published: May 2024

The neutron sources at Oak Ridge National Laboratory use a wide suite of sample environment equipment to deliver extreme conditions for a number of experiments. Much of this instrumentation focuses on extremes of temperature, such as cryostats, closed-cycle refrigerators in both low and high temperature configurations, and radiant heating furnaces. When the temperature is controlled across a large range, thermal deflection effects can notably move the sample and affect its alignment in the beam. Here, we combine these sample environments with neutron imaging and machine vision to determine the motion of a representative sample with respect to the neutron beam. We find vertical sample displacement on the order of 1–2 mm and horizontal displacement that varies from near-negligible to 1.2 mm. While these deflections are not relevant for some of the beamlines at the first target station at the spallation neutron source and the high flux isotope reactor, they will become critical for upcoming instrumentation at the second target station, as well as any instruments targeting sub-mm samples, as neutron sources and optics evolve to smaller and more focused beams. We discuss mitigation protocols and potential modifications to the environment to minimize the effect of misalignment due to thermal deflection.
Wavefront distortion correction in scanning tunneling microscope image
Authors: Jeon Hoyeon , Hus Saban , Park Jewook , Li An-Ping
Published: May 2024

We report an algorithm to identify and correct distorted wavefronts in atomic resolution scanning tunneling microscope images. This algorithm can be used to correct nonlinear in-plane distortions without prior knowledge of the physical scanning parameters, the characteristics of the piezoelectric actuator, or individual atom positions. The 2D image is first defined as a sum of sinusoidal plane waves, where a nonlinear distortion renders a curve for an otherwise ideal linear wavefront. Using the Fourier transforms of local areas of the image, the algorithm generates a wavefront vector field. The identified wavefronts are subsequently linearized for each plane wave without changing lattice orders, giving rise to distortion corrections. Our algorithm is complementary to conventional post-processing algorithms that require prior detection of real space features, which can also be used to correct nonlinear distortions in 2D images acquired by other microscopy techniques.
A novel lidar signal denoising method based on variational mode decomposition optimized using whale algorithm
Authors: Zhao Lin , Mao Jiandong
Published: May 2024

Original lidar return signals are covered by high levels of noise that seriously affect the accuracy of subsequent data processing and inversion. Therefore, it is important to separate the effective signal from the returned signal with noise interference. In this paper, an efficient denoising method based on the variational mode decomposition (VMD) algorithm optimized using the global search strategy-based whale algorithm and the total variational stationary wavelet transform (GSWOA-VMD-SWTTV) is proposed, and this method is applied to denoising of lidar return signals. First, the global search strategy-based whale optimization algorithm (GSWOA) is used to acquire the optimal parameters of the VMD algorithm adaptively, and the lidar return signal is then decomposed by global search strategy-based whale optimization algorithm (GSWOA)-VMD. The effective modal components are then determined using the cross-correlation coefficient method from the decomposed modal components, and total variation stationary wavelet denoising is performed on each effective mode. Finally, the effective modes are reconstructed to obtain a clean lidar return signal. Moreover, to provide further verification of the effectiveness of the proposed method, it is compared with the ensemble empirical mode decomposition (EEMD) method, the complete EEMD with adaptive noise (CEEMDAN) method, the singular value decomposition (SVD) method, and the wavelet threshold method under sunny, cloudy, and dusty weather conditions. The experimental results demonstrate the superior noise reduction performance of the proposed algorithm, which can filter out strong noise from the signal while retaining the complete signal details without distortion; additionally, the proposed method has the highest signal-to-noise ratio and lowest mean square error.
Scale-invariant breathing oscillations and transition of the electron energization mechanism in magnetized discharges
Authors: Zheng Bocong , Fu Yangyang , Wang Keliang , Wang Huihui , Chen Long , Schuelke Thomas , Fan Qi Hua
Published: May 2024

Scale-invariant breathing oscillations are observed in similar magnetized discharges at different spatiotemporal scales via fully kinetic particle-in-cell simulations. With an increase in the similarity invariant B/p, i.e., the ratio of magnetic field to pressure, breathing oscillations are triggered, leading to an appreciable time-averaged potential fall outside the sheath. With the onset and development of breathing oscillations, the electron energization mechanism shifts from sheath energization to direct Ohmic heating in the ionization region due to the change in the potential fall inside and outside the cathode sheath. Based on the scale invariance of the Boltzmann equation and its collision term, the characteristics of breathing oscillations and the transition of the electron energization mechanism are confirmed to be scale-invariant under similar discharge conditions.
Extended short-wave infrared high-speed all-GeSn PIN photodetectors on silicon
Authors: Atalla M. R. M. , Lemieux-Leduc C. , Assali S. , Koelling S. , Daoust P. , Moutanabbir O.
Published: May 2024

There is an increasing need for silicon-compatible high-bandwidth extended-short wave infrared (e-SWIR) photodetectors (PDs) to implement cost-effective and scalable optoelectronic devices. These systems are quintessential to address several technological bottlenecks in detection and ranging, surveillance, ultrafast spectroscopy, and imaging. In fact, current e-SWIR high-bandwidth PDs are predominantly made of III–V compound semiconductors and thus are costly and suffer a limited integration on silicon besides a low responsivity at wavelengths exceeding 2.3 μm. To circumvent these challenges, Ge1−xSnx semiconductors have been proposed as building blocks for silicon-integrated high-speed e-SWIR devices. Herein, this study demonstrates vertical all-GeSn PIN PDs consisting of p-Ge0.92Sn0.08/i-Ge0.91Sn0.09/n-Ge0.89Sn0.11 and p-Ge0.91Sn0.09/i-Ge0.88Sn0.12/n-Ge0.87Sn0.13 heterostructures grown on silicon following a step-graded temperature-controlled epitaxy protocol. The performance of these PDs was investigated as a function of the device diameter in the 10–30 μm range. The developed PD devices yield a high bandwidth of 12.4 GHz at a bias of 5 V for a device diameter of 10 μm. Moreover, these devices show a high responsivity of 0.24 A/W, a low noise, and a 2.8 μm cutoff wavelength, thus covering the whole e-SWIR range.
Emission of ions and electrons correlated with soft and hard x-rays evolution from thermal plasma
Authors: Ahmad Aneesa Naveed , Rafique Muhammad Shahid , Arslan Muhammad , Arshad Tehreem , Armani Ayesha , Mudassar Muhammad , Siddiq Fakhar , Javed Fazila , Shahadat Imran , Muneeb Abdul , Mahmood Hafsa , Amir Mubashra
Published: May 2024

This paper presents a correlation between time evolution of ions and electrons with soft and hard x-rays emitted from argon plasma. The plasma setup comprises of two copper electrodes connected with a dc power supply. Faraday cups were used to monitor time evolution of ions, to extract their energy, temperature, and flux. Double Langmuir probe was employed to determine electron temperature, energy, and density. To explore time-resolved emission of soft x-rays, PIN photodiodes filtered with 24 μm aluminum, 90 μm Mylar, 80 μm copper, and 10 μm silver have been used. To evaluate temporal evolution of hard x-rays, a scintillator–photomultiplier system was utilized. The plasma was generated using argon gas at atmospheric pressure 760 Torr and constant flow rate 5 L/min at 7, 9, and 11 kV. The flux, energy, and temperature of Ar ions increase with the increase in the operating potential. Soft x-ray signals last much longer (3000 ns) than those of electrons' and ions' signals (300 ns). The plasma operated at 11 kV permits highest emission of ions, electrons, and x-rays. The ions, electrons, and hard and soft x-ray irradiation on silicon wafer exhibited the presence of damaged trails. Ion irradiation showed the presence of latent damaged trails. Electron irradiation caused more damage to the Si surface compared to ion irradiation due to higher flux and density. Soft x-rays had a lesser effect as compared to Si exposed to hard x-rays due to higher energy of the hard x-rays. In the case of hard x-rays irradiated Si, erupted volcano-like structure is formed.
Mechanism analysis of the vortex ring and its effects on an axial descending rotor
Authors: Zeng Lifang , Gao Zeming , Xu Tianyu , Wang Liangquan
Published: May 2024

A vortex ring is a flow phenomenon involving a complex toroidal vortex system. When a rotor is in descending flight, it may enter the vortex ring state (VRS), which will affect the rotor’s aerodynamic characteristics and even endanger it. In this paper, to clarify the aerodynamic mechanism by which the vortex ring exerts its effects on an axial descending rotor, an unsteady numerical simulation method for the rotor integrated with structured moving overset grids is proposed and validated using experimental data. This numerical simulation method is then applied to analyze the aerodynamic characteristics of the rotor in descending flight. The variations of the aerodynamic forces and the flow characteristics in the slipstream are analyzed to elucidate the physical mechanisms responsible for the relationships between the aerodynamic loads, flow field, and vortices when the rotor is in the VRS. The effects of the VRS cause a sharp drop in the average aerodynamic forces, which directly affects the safety and reliability of a rotor aircraft. In the slipstream of the descending rotor, a distinct vortex ring forms and moves upward as the velocity of descent increases. The most severe VRS occurs at a nondimensional velocity of descent of 1.13 when the center of the highly unsteady vortex ring is right at the blade tip, and this can be used as an indicator of the VRS. The physical mechanism by which the VRS exerts its effects can be attributed to the low pressure induced by strong vortices. The VRS decreases the pressure on the lower surface of the blade and increases the pressure on the upper surface, resulting in a reduction in the aerodynamic loads. In comparison with the hovering state, the VRS results in a much larger vortex strength and possesses a different vortex structure.
Enhanced thermoelectric performance of Cu2Se thin film derived from potential barrier scattering by incorporating SnSe nano-dispersions
Authors: Wang Qing , Li Zhiliang , Xue Yuli , Gao Zhi , Wang Aiai , Wang Jianglong , Wang Shufang
Published: May 2024

Incorporating nano-dispersions into thermoelectric (TE) materials is an effective approach to enhance the TE properties. Herein, the TE performance of Cu2Se thin film is significantly enhanced by incorporating highly dispersed SnSe nano-inclusions. The high power factor (PF, ∼11.0 μW cm−1 K−2, 310 K) at near room temperature is achieved mainly due to the enhanced energy filtering effect that originated from the potential barrier difference. The total thermal conductivity is decreased owing to the simultaneously reduced electrical conductivity and enhanced phonon scattering. As a result, a high zT value (∼0.59 at 375 K) is achieved, which is about 12 times of pristine Cu2Se film. Remarkably, the calculated average zT values of Cu2Se/SnSe films from 310 to 375 K greatly exceed those of the pristine Cu2Se film, as well as the most state-of-the-art studies. High room-temperature PF and average zT value are crucial for expanding the practical application of Cu2Se at near room temperature. This work provides a feasible strategy to optimize the zT values of some other TE films by introducing nano-dispersions.
A multi-region analysis of unsteady Oseen's equation for accelerating flow past a circular cylinder
Authors: Xu Hai-Long , Wang Chang-Yi , Lei Jie-Chao , Chang Chien-Cheng
Published: May 2024

It is difficult to find a valid high-order (of Reynolds number) analytical approximation to the uniform viscous flow past an infinite circular cylinder by applying perturbation techniques. In this study, we show that by accelerating flow past a circular cylinder with taking unsteady Stokes' solution as an initial approximation, higher-order approximation solutions to unsteady Oseen's equation can be obtained by an iteration scheme of perturbation, which exactly satisfy the boundary conditions. As a matter of fact, the nonlinear (convective) term linearized by Oseen's approximation is overweighted especially near the body surface. To eliminate the overweight, a multi-region analysis is proposed in this study to improve analytical unsteady Oseen's solution so as to extend the valid range of Reynolds numbers. In other words, the flow region is hypothetically divided into several annular regions, and the linearized convective term in each region is modified by multiplying with a Carrier's coefficient c (0 < c ≤ 1). The results show that, when the accelerating parameter in the range of 0.5 ≤ a ≤ 4, the maximum effective Reynolds number Reeff of the fourth-order five-region solution is both much larger than that of Stokes' and Oseen's ones. For example, when a = 0.5, Reeff = 22.26 is roughly eight times that of Stokes' solution (Reeff = 2.67), and nine times that of Oseen's solution (Reeff = 2.41). Moreover, when the instantaneous Reynolds number Re(t) is smaller than the Reeff, the flow separation angle and the wake length are both consistent with the numerical results obtained by accurately solving the full Navier-Stokes equations. In addition, the flow properties, including the drag coefficients, streamline patterns, and the pressure coefficients, as well as the vorticity distributions also agree well with the numerical results. This study represents a significant extension of our previous study for unsteady Stokes' equation [Xu et al., Phys. Fluids 35, 033608 (2023)] to unsteady Oseen's equation and its generalization.