bluuebunny/crossref_metadata_2025 huggingface dataset:
Robust facial landmark detection by probability‐guided hourglass network
Authors: Fan Jingyan , Liang Jiuzhen , Liu Hao , Huan Zhan , Hou Zhenjie , Zhou Xinwen
Published: April 2023

The absence of local features and global shape constraints severely limits the performance of the hourglass network for facial landmark detection in unconstrained environments. Moreover, diverse feature types and scales may result in low accuracy. This paper proposes a probability‐guided hourglass network to enhance the shape constraints for robust facial landmark detection. Firstly, a multi‐scale pre‐processing module is designed to extract features at different scales. Secondly, based on the heatmaps generated by the stacked hourglass network, the coarse localizations are obtained, while the probability maps are generated with local features. Finally, a probability‐based boundary regression method is proposed and the hausdorff distance is modified as the loss function to constrain the feature shape. Adaptive weights are also added to the loss function, which can help relieve the data imbalance problem. Subjective and objective experimental results on the challenging datasets show that this method outperforms the state‐of‐the‐arts on unconstrained conditions.
Barium stars as tracers ofs-process nucleosynthesis in AGB stars
Authors: den Hartogh J. W. , Yagüe López A. , Cseh B. , Pignatari M. , Világos B. , Roriz M. P. , Pereira C. B. , Drake N. A. , Junqueira S. , Lugaro M.
Published: April 2023

Context.Barium (Ba) stars are characterised by an abundance of heavy elements made by the slow neutron capture process (s-process). This peculiar observed signature is due to the mass transfer from a stellar companion, bound in a binary stellar system, to the Ba star observed today. The signature is created when the stellar companion is an asymptotic giant branch (AGB) star.

Aims.We aim to analyse the abundance pattern of 169 Ba stars using machine learning techniques and the AGB final surface abundances predicted by the FRUITYand Monash stellar models.

Methods.We developed machine learning algorithms that use the abundance pattern of Ba stars as input to classify the initial mass and metallicity of each Ba star’s companion star using stellar model predictions. We used two algorithms. The first exploits neural networks to recognise patterns, and the second is a nearest-neighbour algorithm that focuses on finding the AGB model that predicts the final surface abundances closest to the observed Ba star values. In the second algorithm, we included the error bars and observational uncertainties in order to find the best-fit model. The classification process was based on the abundances of Fe, Rb, Sr, Zr, Ru, Nd, Ce, Sm, and Eu. We selected these elements by systematically removings-process elements from our AGB model abundance distributions and identifying the elements whose removal had the biggest positive effect on the classification. We excluded Nb, Y, Mo, and La. Our final classification combined the output of both algorithms to identify an initial mass and metallicity range for each Ba star companion.

Results.With our analysis tools, we identified the main properties for 166 of the 169 Ba stars in the stellar sample. The classifications based on both stellar sets of AGB final abundances show similar distributions, with an average initial mass ofM= 2.23M⊙and 2.34M⊙and an average [Fe/H] = −0.21 and −0.11, respectively. We investigated why the removal of Nb, Y, Mo, and La improves our classification and identified 43 stars for which the exclusion had the biggest effect. We found that these stars have statistically significant and different abundances for these elements compared to the other Ba stars in our sample. We discuss the possible reasons for these differences in the abundance patterns.
Structural Changes and Electrochemical Stability of Ionogel Incorporating Tetraethyl Orthosilicate and PVDF-HFP
Authors: Suen Ji Wei , Elumalai Naveen Kumar , Debnath Sujan , Mubarak Nabisab Mujawar , Lim Chye ing , Reddy M Mohan
Published: April 2023

Ionogels are emerging hybrid materials and are widely studied due to the combination of thermophysical properties from ionic liquid and mechanical integrity from the polymer matrix. Ionic liquid has received wide attention due to its promising properties, high ionic conductivity, and thermal stability. The liquid nature of ionic liquid has restricted its application. Thus, the confinement of ionic liquid within a polymer matrix has allowed ionogel to be applied in strain sensors and lithium-ion batteries. Nevertheless, the compatibility between the polymer matrix and ionic liquid is crucial for ionogel. Incompatibility between polymer host and ionic liquid results in low ionic conductivity, poor mechanical strength, and undesired for practical application. The interaction between polymer matrix and ionic liquid is studied in this study through optical microscopy. The addition of ionic liquid resulted in the disappearance of the polymer matrix’s highly porous nature, as evidenced by the optical microscopy images. This disappearance of the porous nature suggests the compatibility of the polymer matrix with ionogel. Furthermore, the electrochemical stability of the ionogel is also examined through linear sweep voltammetry technique and achieved 2.3V.
Biodiesel Production Catalysed by Magnetic Palm Kernel Shell-Potassium Hydroxide
Authors: Bin Mohiddin Mohd Nurfirdaus , Tan Yie Hua , Periasamy Loshinie A/P , Kansedo Jibrail , Mubarak N.M. , Chan Yen San , Abdullah Mohammad Omar , Lee Keat Teong
Published: April 2023

Biodiesel was prepared by transesterification process using heterogeneous catalyst has received a lot of interest lately as a sustainable source of biofuel. Hence, there is a need to study a generalized reaction kinetic model that can be used for all the reactions involved in biodiesel production. This study produces biodiesel by transesterifying palm oil using magnetic palm kernel shell-potassium hydroxide. The catalyst recorded a BET surface area of 47.72 m2/g. The maximum biodiesel yield, 95.78%, was obtained when reaction temperature and time were 55°C and 2 hours, respectively.
Liquid mean residence time (MRT) in rotating packed bed (RPB) by empirical correlation and residence time distribution (RTD) method using computational fluid dynamics (CFD) simulation
Authors: Zahir Abdul , Kumar Perumal , Saptoro Agus , Tiong Angnes Ngieng Tze , Hameed Samreen , Shah Milinkumar
Published: April 2023

Rotating packed bed (RPB) belongs to a HIGee technology, a process intensification device that can provide better mass transfer rate due to the generation of hyper-gravity under the influence of centrifugal force. While determining the efficiency of the RPB, the MRT of the liquid plays a vital role. The MRT of the RPB is very small and can be tuned in accordance with the mass transfer rate of the solvent to achieve the required outlet concentration of the absorbed gas. There exist two methods, i.e., empirical correlation and the residence time distribution (RTD) method. The applicability of both methods still needs to be investigated for better prediction of MRT in RPB. The current study compares the MRT of the two of the most widely employed techniques, i.e., MRT by empirical correlation and the RTD approach using the Computational Fluid Dynamics (CFD). The difference between the MRT by both methods lies between 30-38%. The results show that the RTD better predicts the MRT in the RPB as compared to the Burns empirical correlation.
Synthesis and Antifungal Evaluation of Magnetic Magnesium Oxide Nanoparticles Against Fusarium Oxysporum
Authors: Le Wee Jia , Chan Yen San , Law Ming Chiat
Published: April 2023

Hybrid nanoparticles (NPs) have received much interest over the past decades because they have the potential to overcome the limits of single-component particles. This study proposes a hybrid magnetic magnesium oxide (m-MgO) NPs to combat the plant pathogenic fungus,Fusarium oxysporum(F. oxysporum). The m-MgO NPs were synthesized via ultrasonic mediated sol-gel method. UV-visible spectrometry confirms the successful formation of m-MgO NPs. In addition, the magnetic activity of m-MgO NPs was illustrated through a preliminary magnetic activity study. A disc diffusion assay was carried out to determine the effectiveness of m-MgO NPs to inhibit the growth ofF. oxysporum. The results showed that the zone of inhibition was 7.58 ± 0.30 mm at 10 mg/mL, suggesting that the synthesized m-MgO NPs are an effective fungicide to inhibit the growth ofF. oxysporum.
Art for climate change response of adolescents: Methodology adopted for the transformational individual sphere study
Authors: Oanh Truong Thi Kim , Giridharan Beena
Published: April 2023

The investigative study attempts to elicit how art-based science experiences on the topic of climate crisis may shape young participants’ reactions to climate change and demonstrates the potential of transformational pathways created through art-integrated science communication activities at the level of the subjects’ sphere. The study applied Solomon’s four-group experimental design using two control and two treatment groups to study the transformation between groups. This research design allows researchers to assess the fundamental revision of testing, treatment/intervention and the remarkable correlation between testing and treatment (Daily, 2017).

Although this research is a small-scale exploratory study, the results are validated using multiple data collection and analysis methods. At the core of the study, it aims to make an in-depth and critical interpretation based on the data analysis through a set of codes. The codes are various in the length of the text, from which group (control or experimental groups) to highly conceptual answers (given by four groups). The study advocates that science communication to the lay society through art-informed collaboration should be considered to achieve sustainability outcomes. The findings are expected to show how art can influence and effectively tell young people, as the future generation, creative and attractive narratives with proper knowledge of climate change adaptation.
Toughness and binding number bounds of star-like and path factor
Authors: Feng Xinge , Deng Xingchao
Published: April 2023

Let $ \mathcal{L}$ be a set which consists of some connected graphs. LetEbe a spanning subgraph of graphG. It is called a $ \mathcal{L}$-factor if every component of it is isomorphic to the element in $ \mathcal{L}$. In this contribution, we give the lower bounds of four parameters (t(G), I(G), I′(G),bind (G)) ofG, which force the graphGadmits a ({K1,i:q ≤ i ≤ 2q − 1} ∪ {K2q+1})-factor forq ≥ 2 and a {P2, P2q+1}-factor forq ≥ 3 respectively. The tightness of the bounds are given.
Aktuelle Empfehlungen zu körperlicher Aktivität bei
Cancer Survivors – ein narratives Review
Authors: Salchow Jannike , Sinn Marianne , Berling-Ernst Anika
Published: April 2023

Krebserkrankungen sind nach Herz-Kreislauf-Erkrankungen die
zweithäufigste Todesursache in Deutschland. Die Zahl der
Krebsüberlebenden, sogenannten „Cancer Survivors“, nimmt
aufgrund verbesserter Früherkennungsmethoden und Therapieformen stetig
zu.

Allerdings ist die Gruppe der Cancer Survivors sehr heterogen und häufig
von Spät- und Langzeitfolgen der Krebstherapie betroffen (u. a.
Fatigue, Depressionen, Ängste). Viele dieser Nebenwirkungen
können effektiv durch eine angepasste Bewegungstherapie gelindert
werden. Derzeit existieren jedoch keine einheitlichen Empfehlungen zu
körperlicher Aktivität, und es gibt keine standardisierte
Bewegungstherapie für diese Zielgruppe.

Ziel dieses Artikels ist es, einen Überblick über die aktuellen
Empfehlungen der Fachgesellschaften bei körperlicher Aktivität
für Cancer Survivors zu geben und diese untereinander zu vergleichen.
Einheitliche Empfehlungen, wie sie im Rahmen der aktuellen Erstellung der
S3-Leitlinien „Bewegungstherapie bei onkologischen Erkrankungen“
formuliert werden, sowie strukturierte Survivorship-Programme, über die
Betroffene einen Zugang zu Bewegungsangeboten erhalten, sind ein wichtiger
Schritt im Rahmen der onkologischen Versorgung.
Das Konzept des DVO Frakturrisikorechners
Authors: Glüer Claus-C. , Engelke Klaus , Thomasius Friederike
Published: April 2023

Die Abschätzung des Frakturrisikos ist eine Kernaufgabe bei der
Identifikation Osteoporose gefährdeter PatientInnen. Für diesen
Zweck wurden verschiedene Risikorechner entwickelt. Trotz dessen besteht eine
erhebliche Unterversorgung von Osteoporosepatient:innen, was auch an
unzureichender Identifikation Betroffener liegt. Um hier eine Verbesserung zu
erzielen, wurde der DVO Frakturrisiko Rechner entwickelt. In diesem Beitrag
werden die Defizite bisheriger Risikorechner aufgeführt, um daraus das
Konzept des DVO Frakturrisiko Rechners abzuleiten. Kernaspekte sind i) ein breit
gefächertes Casefinding über 33 Evidenz-basiert validierte
Frakturrisikofaktoren, ii) der Fokus auf Schenkelhals- und
Wirbelkörperfrakturrisiko, iii) eine Berechnung des 3-Jahres
Frakturrisikos, optional mit 1-Jahresdaten bei hohem imminenten Frakturrisiko
und iv) Osteodensitometrie an Lendenwirbelsäule und proximalem Femur.
Die Risikoabschätzung basiert auf deutschen Referenzdaten. Das
Frakturrisiko wird aus dem Risiko von Personen, die keine der erhobenen
klinischen Risikofaktoren aufweisen, über ein geschlechts-spezifisches
multiplikatives Modell, das Alter, die relativen Risiken der zwei
stärksten klinischen Risikofaktoren und Osteodensitometrieergebnisse
berücksichtigt, ermittelt. Ziel ist die Implementierung als App, die den
Osteolog:innen des DVO kostenfrei zur Verfügung gestellt werden soll.
Bis zur Zertifizierung der App wird für eine Übergangszeit ein
vereinfachtes Modell in Tabellenform angeboten. Risikorechner können die
ärztliche Beurteilung nur unterstützen, sie nicht ersetzen, aber
der DVO Frakturrisiko Rechner wird hoffentlich dazu beitragen, die
Unterversorgung von Osteoporosepatient:innen zu verringern, in dem er hilft, in
effektiver Weise Risikopatient:innen zu identifizieren.
Synthesis of Chiral Spiro[4.5]decadienones via Chirality-Transferring Oxidative Intramolecular Cyclization of Allenylsilane-Tethered Phenols
Authors: Sakaguchi Kazuhiko , Kishimoto Ryoma , Iwakiri Yuka , Nishimura Takahiro
Published: April 2023

Reactions of phenols having a methylene-tethered chiral allenylsilane at the para position with a hypervalent iodine reagent result in chirality-transferring oxidative intramolecular cyclization accompanied by dearomatization of the phenol to stereoselectively give spiro[4.5]decadienones possessing a silylethynyl group.
A Retrospective Analysis of Autologous Stem Cell Transplantation Outcomes in Adult Philadelphia Chromosome Positive-Acute Lymphoblastic Leukemia
Authors: Satti Kiran Kumar , Mehra Nikita , Kalaiyarasi Jayachandran Perumal , Radhakrishnan Venkataraman , Karunakaran Parathan , Rathinam Krishna , Mani Samson , Ganesan Prasanth
Published: April 2023

Introduction Philadelphia chromosome positivity (Ph + ) is a poor prognostic feature in adult acute lymphoblastic leukemia (ALL). Allogenic hematopoietic stem cell transplantation in first complete remission (CR1) is recommended. There is limited literature on the role of consolidation autologous stem cell transplantation (ASCT). This study was undertaken to assess the potential of consolidation ASCT in CR1 in adults with Ph + ALL.

Objectives The aim of this study was to analyze the safety and efficacy of ASCT in CR1 in adults with Ph + ALL.

Materials and Methods Adult patients diagnosed with Ph + ALL who underwent ASCT in CR1 after modified ALL-BFM95 protocol from 2015 to 2017 were included. Patients who achieved major molecular response or better were considered for ASCT with cyclophosphamide-total body irradiation regimen and peripheral blood stem cells infused on day 0. Toxicities as per Common Terminology Criteria for Adverse Event v4.0, disease-free survival (DFS), and overall survival (OS) were assessed. Inclusion criteria: Following patients were included—patients aged 18 years and above diagnosed with Ph + ALL; patients receiving BFM-95 induction chemotherapy protocol; patients who achieved CR after induction therapy; nonavailability of human leukocyte antigen match from a matched sibling donor or matched unrelated donor. Exclusion criteria: Patients not willing or unfit for ASCT and patients planned for allogenic hematopoietic stem cell transplantation were excluded.

Results Six adult patients with Ph + ALL underwent ASCT in CR1 (median age: 23 [range: 19–36] years, five patients were males [83%]). Imatinib was started at a median of 11 days from the start of induction IA (range: 10–21). Five patients achieved morphological CR after induction 1A and, one patient at the end of induction 1B. The median time to ASCT (from diagnosis) was 8 months (range: 6.4–13). All the six patients had disease relapse and died due to progressive ALL. The median DFS and OS were 19.2 months and 23.3 months, respectively.

Conclusion Consolidation ASCT yielded poor outcomes in this study. There was a significant delay from diagnosis to ASCT, which might have impacted the results.
Impact of the COVID-19 Pandemic on the Psychological Well-Being of Health Care Professionals in India
Authors: Siddiqui Hiba , Garg Shubham , Julka Pramod Kumar , Chaturvedi Aditi , Choudhri Sharan , Arora Ramandeep Singh
Published: April 2023

Introduction and Objective Health care professionals (HPs) have been at the forefront facing the pressures and uncertainties of the COVID-19 pandemic, and thus have a higher psychological vulnerability. The incidence of psychological distress, which can negatively affect an HP's work efficiency and long-term well-being, has not been studied in depth in India.

Materials and Methods A multicentric study was conducted using the digital means of communication across Max Healthcare between June and August 2020. HPs in the department of oncology, including doctors, nurses, and other support staff, were invited to voluntarily participate in the self-administered online survey. A total of 87 HPs in oncology (41 doctors, 28 nurses, and 18 in other fronts) were assessed using the 12-item General Health Questionnaire (GHQ-12). Outcome of interest was psychological distress (defined as a GHQ-12 score >15).

Results The overall incidence of psychological distress among HPs in oncology during the COVID-19 pandemic was 17.20%. Significantly higher levels of psychological distress were observed among HPs with a history of psychiatric illness (p = 0.003), and among HPs with a work experience of less than 10 years (p = 0.017).

Conclusion The COVID-19 pandemic had a significant impact on the psychological well-being of HPs in India. This study implicated the recognition of the psychological well-being of HPs in oncology as an unmet need during the COVID-19 pandemic, further recommending efforts toward increasing accessibility of mental health services for them.
A Review on the Role of Molecular Genetics in the Diagnostic Workup of BCR::ABL1-Negative Myeloproliferative Neoplasms
Authors: Maddali Madhavi , Arunachalam Arun Kumar , Kapadia Alpesh Kumar BipinBhai , Kulkarni Uday Prakash , Balasubramanian Poonkuzhali
Published: April 2023

The diagnostic evaluation of myeloproliferative neoplasms (MPNs) depends on the close correlation between clinical features, morphologic assessment of a trephine bone marrow biopsy, and molecular markers. Typically, MPNs have driver mutations in JAK2, CALR, or MPL, as well as mutations in genes related to epigenetic regulation, RNA splicing, and signaling. Mutations in these genes are a hallmark of diagnostic, prognostic, and therapeutic assessment in patients with MPNs. In line with the World Health Organization classification, all myeloproliferative disorders require molecular characterization to support diagnoses or confirm entities defined by underlying molecular abnormalities. A structured molecular analysis workflow is essential for a rapid and cost-effective diagnosis of MPN. The purpose of this review is to explore the role of molecular diagnostics in the assessment of BCR::ABL1-negative MPNs.
Operation characteristics of soil blasting vibration test device under vibration load
Authors: Guo Dongdong , Wang Meng , Jiang Nan , Zeng Yinyong , Cao Haiqing , Wang Dianyong , Lu Jun , Wu Tingyao
Published: April 2023

To improve the accuracy of vibration velocity monitoring during blasting in soil layers, this paper provides a method and device for data correction by combining finite element software and actual engineering test data. Based on the length of the test pedestal exposed to the surface of the geotechnical body, the finite element structural model corresponding to each length of the test pedestal is established. Moreover, a predetermined external excitation load is applied outside the finite element model and the correction function of the vibration data is obtained by analysis of the stress and vibration data. The device solves the problem of low accuracy of vibration velocity measurement in soil and establishes a correction method for measurement data. The results show the following: (1) With the propagation of blasting seismic waves, the maximum stress values of the test device appear in the footwall position, the middle of the extension rod, and the bottom position in that order. (2) At the end of the test, there is an obvious phenomenon of speed amplification at the top of the test device. (3) As the length of the test device exposed to the ground increases, the particle peak vibration velocity (PPV) of the test device varies exponentially with the PPV of the ground and the range of variation of the vibration velocity in the X-direction is the largest.
Nonlinear models for coupling the effects of stimulated Raman scattering to inertial confinement fusion codes
Authors: Stark D. J. , Yin L. , Nguyen T. B. , Chen G. , Chacon L. , Haines B. M. , Green L.
Published: April 2023

Laser plasma instabilities (LPI) reduce driver-target coupling, alter implosion symmetry, and therefore can fundamentally limit fusion performance in inertial confinement fusion (ICF). Developing a predictive modeling capability for LPI effects can critically advance the success of the field. We perform vector particle-in-cell simulations of multi-speckled laser beams undergoing stimulated Raman scattering (SRS) at various densities and intensities relevant to mainly indirectly driven and a subset of parameter space for directly driven ICF systems, focusing on the regimes with intensities above the onset of electron trapping. Based on the wavenumber of the SRS daughter electron plasma wave, we identify several regions with underpinning SRS saturation physics: the electron-trapping dominated region with intermediate kλD values, the strong Landau damping region at larger kλD values, and the region where the Langmuir decay instability arises at lower kλD values. We develop a nonlinear SRS reflectivity model that features the base trapping-dominated scaling of (kλD)−4 and its modifications. Electron trapping deforms the initialized electron distribution functions, and we have developed a new δf-Gaussian-mixture algorithm for an accurate characterization of the trapped hot electron population. With this SRS hot electron description, we construct a nonlinear energy deposition model and a hot electron source model—based on a modified Manley–Rowe relation—suitable for including SRS effects as a sub-grid module in a high-fidelity ICF design code.
Equation of state of hard-disk fluids under single-file confinement
Authors: Montero Ana M. , Santos Andrés
Published: April 2023

The exact transfer-matrix solution for the longitudinal equilibrium properties of the single-file hard-disk fluid is used to study the limiting low- and high-pressure behaviors analytically as functions of the pore width. In the low-pressure regime, the exact third and fourth virial coefficients are obtained, which involve single and double integrals, respectively. Moreover, we show that the standard irreducible diagrams do not provide a complete account of the virial coefficients in confined geometries. The asymptotic equation of state in the high-pressure limit is seen to present a simple pole at the close-packing linear density, as in the hard-rod fluid, but, in contrast to the latter case, the residue is 2. Since, for an arbitrary pressure, the exact transfer-matrix treatment requires the numerical solution of an eigenvalue integral equation, we propose here two simple approximations to the equation of state, with different complexity levels, and carry out an extensive assessment of their validity and practical convenience vs the exact solution and available computer simulations.
Reconfigurable metatiles with circular maze-like space-coiling-based acoustic metastructure for low-to-mid frequency sound attenuation
Authors: Kumar Sanjay , Pueh Lee Heow
Published: April 2023

This study presents a compact, lightweight, and reconfigurable acoustic metatile for sound mitigation applications. The metatile prototype is designed based on a circular maze-like acoustic metastructure, which utilizes a space-coiling technique for enhanced acoustic performance in low-to-mid frequencies. The proposed labyrinthine acoustic metadisk structure comprises a central hollow front face sheet and two coiling-up backing cavities. Experimental results show that the metadisk has high absorption peaks of 0.81 and 0.75 at 574 and 1436 Hz, respectively, and exhibits high sound transmission loss (STL) values ( ≥25 dB) in separate wide frequency bands between 100–580 Hz and 820–1600 Hz. Based on the metadisk samples, metatiles are constructed, which are 30.5 × 30.5 cm 2 in size. The acoustic performance of these metatiles is investigated in two distinct scenarios. Two prototypes of the acoustic metatile are presented: the metacage and the metapanel. The metacage is a cubical box-shaped structure constructed using five metatiles, which showed a wideband insertion loss of ≥10 dB in 200–16 000 Hz and ≥20 dB over 400–5000 Hz. On the other hand, the metapanel is constructed using nine metatiles, which exhibited STL values of >20 dB over 125–5000 Hz and had a sound transmission class rating of 34. The study highlights the potential of circular maze-like space-coiling-based acoustic disk metastructures to be reconfigured into metatiles and assembled into a metacage or metapanel for practical sound mitigation applications.
Control of the interaction between pinning disorder and domain walls in Pt/Co/AlOx ultrathin films by He+ ion irradiation
Authors: Balan Cristina , van der Jagt Johannes W. , Peña Garcia Jose , Vogel Jan , Ranno Laurent , Bonfim Marlio , Ravelosona Dafiné , Pizzini Stefania , Jeudy Vincent
Published: April 2023

We have studied the effect of He+ irradiation on the dynamics of chiral domain walls in Pt/Co/AlOx trilayers in the creep regime. Irradiation leads to a strong decrease in the depinning field and a non-monotonous change of the effective pinning barriers. The variations of domain wall dynamics result essentially from the strong decrease in the effective anisotropy constant, which increases the domain wall width. The latter is found to present a perfect scaling with the length-scale of the interaction between domain wall and disorder, ξ. On the other hand, the strength of the domain wall–disorder interaction, fpin, is weakly impacted by the irradiation, suggesting that the length-scales of the disorder fluctuation remain smaller than the domain wall width.
Electron beam-induced current imaging of ferroelectric domains and local polarization reversal in Hf0.5Zr0.5O2
Authors: Korostylev Evgeny , Mikheev Vitalii , Chernikova Anna G. , Zhuk Maksim Yu. , Chouprik Anastasia , Negrov Dmitry V.
Published: April 2023

Because of their full compatibility with CMOS technology, HfO2-based ferroelectrics, and especially Hf0.5Zr0.5O2 (HZO), attract a lot of attention. However, the overwhelming majority of measurement techniques provides only information about the cumulative electrical response of many domains of HZO, i.e., at the macroscopic level. So far, only piezoresponse force microscopy technique was applied to visualize distinct ferroelectric domains in HZO and to analyze the local switching behavior in the microscopic level. This work introduces the possibility of using electron beam-induced current (EBIC) technique in the scanning electron microscope to visualize the gradual polarization reversal of HZO and to obtain the local polarization dynamics. We show that although the local EBIC signal is affected by surrounding domains, studying the variations in the ferroelectric response of individual domains as well as the spread of the local stiffness and local imprint is possible by this method. Besides, we show the connection between the EBIC current and an electric field across passive non-ferroelectric layers at interfaces between HZO and metal electrodes, which opens up additional opportunities to use the EBIC technique for investigations of interface-dependent properties of HZO ferroelectrics in the future.
Low-frequency magnetic microwave absorber using reactive ground for extended bandwidth
Authors: Fu Bin , Wan Guo-Bin , Ma Xin , Cao Chang
Published: April 2023

A design method to extend the operating bandwidth of a low-frequency magnetic microwave absorber is presented. According to the mapped impedance distribution from the design objective, a synthesized reactive ground consisting of a triple-ring array, instead of the perfect electric conductor (PEC), is conveniently placed at the back of a commercially available magnetic sheet to realize impedance matching. Compared with the conventional PEC, the reactive ground extends the operating bandwidth of reflection coefficient being less than −10 dB by introducing four consecutive absorption peaks so that the optimized structure achieves broadband absorption from 2.3 to 4.3 GHz with a thickness of 0.027 times the free-space wavelength at the lowest operating frequency and a 60.6% fractional bandwidth which is nearly two times that of the conventional structure. The physical mechanism is further investigated through the distributions of current flow and power loss. Finally, a prototype is fabricated and measured. The good agreement between the simulated and measured results verifies the effectiveness of the presented design method.
Phase separation and aggregation in multiblock chains
Authors: Panagiotopoulos Athanassios Z.
Published: April 2023

This paper focuses on phase and aggregation behavior for linear chains composed of blocks of hydrophilic and hydrophobic segments. Phase and conformational transitions of patterned chains are relevant for understanding liquid–liquid separation of biomolecular condensates, which play a prominent role in cellular biophysics and for surfactant and polymer applications. Previous studies of simple models for multiblock chains have shown that, depending on the sequence pattern and chain length, such systems can fall into one of two categories: displaying either phase separation or aggregation into finite-size clusters. The key new result of this paper is that both formation of finite-size aggregates and phase separation can be observed for certain chain architectures at appropriate conditions of temperature and concentration. For such systems, a bulk dense liquid condenses from a dilute phase that already contains multi-chain finite-size aggregates. The computational approach used in this study involves several distinct steps using histogram-reweighting grand canonical Monte Carlo simulations, which are described in some level of detail.
Regulation of droplet impacting on superhydrophobic surfaces: Coupled effects of macrostructures, wettability patterns, and surface motion
Authors: Chu Fuqiang , Li Shuxin , Hu Zhifeng , Wu Xiaomin
Published: April 2023

Superhydrophobic surfaces have shown great application prospects due to their excellent water repellency in many applications involving fluid–surface interactions. As a ubiquitous fluid–surface interaction phenomenon, droplet impacting dynamics has a crucial effect on the application of superhydrophobic surfaces. In this Perspective, we summarize the basic process of droplet impacting on superhydrophobic surfaces and introduce the two most concerned parameters that describe the droplet impacting dynamics, i.e., the maximum spreading coefficient and the contact time. We then review two improvement strategies for superhydrophobic surfaces: one is to construct macrostructures and the other is to set wettability patterns on the surface. The former strategy shows great potential in reducing the droplet contact time, and the latter one can accurately regulate the behavior of impacting droplets. The motion of superhydrophobic surfaces also changes the droplet impacting dynamics due to the additional aerodynamic effect or energy input, which arouses attention recently. However, only the individual influence of each factor (e.g., macrostructures, wettability patterns, or surface motion) on the droplet impacting dynamics has been focused in literature, so we write this Perspective to emphasize the importance and urgency of studying the coupled effects of these three factors.
Mechanistic origins of methyl-driven Overhauser DNP
Authors: Perras Frédéric A. , Matsuki Yoh , Southern Scott A. , Dubroca Thierry , Flesariu Dragos F. , Van Tol Johan , Constantinides Christos P. , Koutentis Panayiotis A.
Published: April 2023

The Overhauser effect in the dynamic nuclear polarization (DNP) of non-conducting solids has drawn much attention due to the potential for efficient high-field DNP as well as a general interest in the underlying principles that enable the Overhauser effect in small molecules. We recently reported the observation of 1H and 2H Overhauser effects in H3C- or D3C-functionalized Blatter radical analogs, which we presumed to be caused by methyl rotation. In this work, we look at the mechanism for methyl-driven Overhauser DNP in greater detail, considering methyl librations and tunneling in addition to classical rotation. We predict the temperature dependence of these mechanisms using density functional theory and spin dynamics simulations. Comparisons with results from ultralow-temperature magic angle spinning-DNP experiments revealed that cross-relaxation at temperatures above 60 K originates from both libration and rotation, while librations dominate at lower temperatures. Due to the zero-point vibrational nature of these motions, they are not quenched by very low temperatures, and methyl-driven Overhauser DNP is expected to increase in efficiency down to 0 K, predominantly due to increases in nuclear relaxation times.
Epistasis reduces fitness costs of influenza A virus escape from stem-binding antibodies
Authors: Lee Chung-Young , Raghunathan Vedhika , Caceres C. Joaquin , Geiger Ginger , Seibert Brittany , Cargnin Faccin Flavio , Gay L. Claire , Ferreri Lucas M. , Kaul Drishti , Wrammert Jens , Tan Gene S. , Perez Daniel R. , Lowen Anice C.
Published: April 2023

The hemagglutinin (HA) stem region is a major target of universal influenza vaccine efforts owing to the presence of highly conserved epitopes across multiple influenza A virus (IAV) strains and subtypes. To explore the potential impact of vaccine-induced immunity targeting the HA stem, we examined the fitness effects of viral escape from stem-binding broadly neutralizing antibodies (stem-bnAbs). Recombinant viruses containing each individual antibody escape substitution showed diminished replication compared to wild-type virus, indicating that stem-bnAb escape incurred fitness costs. A second-site mutation in the HA head domain (N129D; H1 numbering) reduced the fitness effects observed in primary cell cultures and likely enabled the selection of escape mutations. Functionally, this putative permissive mutation increased HA avidity for its receptor. These results suggest a mechanism of epistasis in IAV, wherein modulating the efficiency of attachment eases evolutionary constraints imposed by the requirement for membrane fusion. Taken together, the data indicate that viral escape from stem-bnAbs is costly but highlights the potential for epistatic interactions to enable evolution within the functionally constrained HA stem domain.
Long-duration wind tunnel flights reveal exponential declines in protein catabolism over time in short- and long-distance migratory warblers
Authors: Elowe Cory R. , Groom Derrick J. E. , Slezacek Julia , Gerson Alexander R.
Published: April 2023

During migration, long-distance migratory songbirds may fly nonstop for days, whereas shorter-distance migrants complete flights of 6 to 10 h. Fat is the primary fuel source, but protein is also assumed to provide a low, consistent amount of energy for flight. However, little is known about how the use of these fuel sources differs among bird species and in response to flight duration. Current models predict that birds can fly until fat stores are exhausted, with little consideration of protein’s limits on flight range or duration. We captured two related migratory species—ultra long-distance blackpoll warblers (
Setophaga striata
) and short-distance yellow-rumped warblers (
Setophaga coronata
)—during fall migration and flew them in a wind tunnel to examine differences in energy expenditure, overall fuel use, and fuel mixture. We measured fat and fat-free body mass before and after flight using quantitative magnetic resonance and calculated energy expenditure from body composition changes and doubly labeled water. Three blackpolls flew voluntarily for up to 28 h—the longest wind tunnel flight to date—and ended flights with substantial fat reserves but concave flight muscle, indicating that protein loss, rather than fat, may actually limit flight duration. Interestingly, while blackpolls had significantly lower mass-specific metabolic power in flight than that of yellow-rumped warblers and fuel use was remarkably similar in both species, with consistent fat use but exceptionally high rates of protein loss at the start of flight that declined exponentially over time. This suggests that protein may be a critical, dynamic, and often overlooked fuel for long-distance migratory birds.
Tight junction protein occludin is an internalization factor for SARS-CoV-2 infection and mediates virus cell-to-cell transmission
Authors: Zhang Jialin , Yang Wenyu , Roy Sawrab , Liu Heidi , Roberts R. Michael , Wang Liping , Shi Lei , Ma Wenjun
Published: April 2023

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spreads efficiently by spike-mediated, direct cell-to-cell transmission. However, the underlying mechanism is poorly understood. Herein, we demonstrate that the tight junction protein occludin (OCLN) is critical to this process. SARS-CoV-2 infection alters OCLN distribution and expression and causes syncytium formation that leads to viral spread. OCLN knockdown fails to alter SARS-CoV-2 binding but significantly lowers internalization, syncytium formation, and transmission. OCLN overexpression also has no effect on virus binding but enhances virus internalization, cell-to-cell transmission, and replication. OCLN directly interacts with the SARS-CoV-2 spike, and the endosomal entry pathway is involved in OCLN-mediated cell-to-cell fusion rather than in the cell surface entry pathway. All SARS-CoV-2 strains tested (prototypic, alpha, beta, gamma, delta, kappa, and omicron) are dependent on OCLN for cell-to-cell transmission, although the extent of syncytium formation differs between strains. We conclude that SARS-CoV-2 utilizes OCLN as an internalization factor for cell-to-cell transmission.
Modeling global oceanic nitrogen deposition from food systems and its mitigation potential by reducing overuse of fertilizers
Authors: Liu Lei , Xu Wen , Wen Zhang , Liu Pu , Xu Hang , Liu Sheng , Lu Xiankai , Zhong Buqing , Guo Yixin , Lu Xiao , Zhao Yuanhong , Zhang Xiuying , Wang Songhan , Vitousek Peter M. , Liu Xuejun
Published: April 2023

Growing population and consumption pose unprecedented demands on food production. However, ammonia emissions mainly from food systems increase oceanic nitrogen deposition contributing to eutrophication. Here, we developed a long-term oceanic nitrogen deposition dataset (1970 to 2018) with updated ammonia emissions from food systems, evaluated the impact of ammonia emissions on oceanic nitrogen deposition patterns, and discussed the potential impact of nitrogen fertilizer overuse. Based on the chemical transport modeling approach, oceanic ammonia-related nitrogen deposition increased by 89% globally between 1970 and 2018, and now, it exceeds oxidized nitrogen deposition by over 20% in coastal regions including China Sea, India Coastal, and Northeastern Atlantic Shelves. Approximately 38% of agricultural nitrogen fertilizer was excessive, which corresponds to 15% of global oceanic ammonia-related nitrogen deposition. Policymakers and water quality managers need to pay increasingly more attention to ammonia associated with food production if the goal of reducing coastal nitrogen pollution is to be achieved for Sustainable Development Goals.
Two aspects of high interfacial strength regarding the cracking behaviour of MCrAlY-coated superalloys
Authors: Song Jianan , Huang Jia , Lu Zhilai , Qi Hongyu
Published: April 2023

In this study, we investigated the cracking behaviour of MCrAlY-coated superalloys having different interfacial strengths. A cyclic damage-coupled cohesive zone model is proposed to describe the fatigue crack initiation and propagation at the interface between the coating and the substrate. Our results indicate that a high interfacial strength leads to a significant stress concentration owing to the increasing interfacial stiffness. Moreover, high interfacial strength delays interfacial crack propagation but promotes the accumulation of deformation energy in the substrate, which accelerates fatigue crack initiation in the substrate. This work shows two aspects of high interfacial strength and can provide new insights into coating design.
Biomaterial strategies to combat implant infections: new perspectives to old challenges
Authors: Braem Annabel , Kamarudin Nur Hidayatul Nazirah , Bhaskar Nitu , Hadzhieva Zoya , Mele Andrea , Soulié Jérémy , Linklater Denver P. , Bonilla-Gameros Linda , Boccaccini Aldo R. , Roy Ipsita , Drouet Christophe , Ivanova Elena P. , Mantovani Diego , Basu Bikramjit
Published: April 2023

Peri-implant infection is rapidly becoming an – if not the most – important clinical challenge for indwelling medical devices. To alleviate the global rise in antibiotic use for the treatment of such infections, a plethora of biomaterials/bioengineering-based antimicrobial strategies are emerging to restrict or ideally to eliminate microbial adhesion and biofilm formation on implant surfaces. Yet, the development of such approaches faces specific challenges, like biocompatibility concerns, reduced antimicrobial effectiveness, long-term stability issues and antibiotic resistance development, which limit translation to the clinic. This review provides insights into the antimicrobial activity of current state-of-the-art biomaterial-based approaches to address the aforementioned issues. Translational research strategies and regulatory framework are also emphasised as key elements facilitating clinical implementation of anti-infective biomaterials. This review closes with the vision that the integration of computational tools and experimental databases using artificial intelligence (AI) would provide new insights for the accelerated development of next-generation biomaterial-based antimicrobial strategies.
Controlling solar radiation forces with graphene in plasmonic metasurface
Authors: Soleymani Sina , Seyyedmasoumian Sevda , Attariabad Asma , Soleymani Sepideh , Bayat Farzaneh , Sabet Hamid
Published: April 2023

Controlling and harvesting solar radiation pressure is a significant challenge, however, there are a few potential solutions, which are suitable for several key applications. In this study, an electrically tunable plasmonic metasurface is designed for the visible spectrum. Moreover, the normal and the tangential optical forces acting on the metasurface are calculated. Whilst presenting high efficiency in the anomalous reflection, the designed active metasurface provides tunability of optical forces acting on the metasurface. The metasurface is composed of tapered silver cells embedded on top of the graphene layer with 20 layers of graphene sheets. Hence, the transferred momentum to the metasurface can be controlled by tuning the Fermi level of graphene sheets. Our results can provide a suitable platform for optical force control desired in tunable radiation pressure harvesting, micro vehicles, solar sailing, and optical tweezers.
Coexisting attractors and multi-stability within a Lorenz model with periodic heating function
Authors: Ahmadi Atefeh , Parthasarathy Sriram , Natiq Hayder , Rajagopal Karthikeyan , Huerta-Cuellar Guillermo , Jafari Sajad
Published: April 2023

In this paper, the classical Lorenz model is under investigation, in which a periodic heating term replaces the constant one. Applying the variable heating term causes time-dependent behaviors in the Lorenz model. The time series produced by this model are chaotic; however, they have fixed point or periodic-like qualities in some time intervals. The energy dissipation and equilibrium points are examined comprehensively. This modified Lorenz system can demonstrate multiple kinds of coexisting attractors by changing its initial conditions and, thus, is a multi-stable system. Because of multi-stability, the bifurcation diagrams are plotted with three different methods, and the dynamical analysis is completed by studying the Lyapunov exponents and Kaplan-Yorke dimension diagrams. Also, the attraction basin of the modified system is investigated, which approves the appearance of coexisting attractors in this system.
Exact solutions of the Schrödinger equation for another class of hyperbolic potential wells
Authors: Wang Xiao-Hua , Chen Chang-Yuan , You Yuan , Sun Dong-Sheng , Lu Fa-Lin , Dong Shi-Hai
Published: April 2023

In this work a new scheme is proposed to study the exact solutions of another class of hyperbolic potentials U

p
. We first obtain two linearly dependent eigenfunctions corresponding to the same even-parity state or odd-parity state by taking different variable substitutions and function transformations and then find that their solutions can be expressed analytically as the confluent Heun functions (CHFs). The Wronskian determinant which can be constructed by two linearly dependent eigenfunctions is used to get the corresponding energy spectrum equations with respect to even- and odd-parity states. According to energy spectrum equation, we can first study the intersection distribution between F(ε) which is defined by the Wronskian determinant and energy levels ε, and then determine the total number of bound states as well as the exact energy levels. Substitution of the obtained energy levels into the eigenfunction allows us to obtain the normalized eigenfunction, which can be illustrated easily in graphics. Finally, we notice that only the potential well U
2 exists a polynomial solution for some special potential well depths u.
Anti-Stokes/Stokes temperature calibration and its application in laser-heating diamond anvil cells
Authors: Zhao 赵 Minmin 旻旻 , Wu 吴 Binbin 彬彬 , Liu 刘 Jingyi 静仪 , Lei 雷 Li 力
Published: April 2023

Anti-Stokes/Stokes Raman peak intensity ratio was used to infer sample temperatures, but the influence factors of system correction factors were not clear. Non-contact in-situ anti-Stokes/Stokes temperature calibration was carried out for up to 1500 K based on six different samples under two excitation light sources (±50 K within 1000 K, ±100 K above 1000 K), and the system correction factor γ was systematically investigated. The results show that the correction factor γ of anti-Stokes/Stokes thermometry is affected by the wavelength of the excitation light source, Raman mode peak position, temperature measurement region and other factors. The anti-Stokes/Stokes thermometry was applied to the laser-heating diamond anvil cell (LHDAC) experiment to investigate the anharmonic effect of hBN under high temperature and high pressure. It is concluded that the strong anharmonic effect caused by phonon scattering at low pressure gradually changes into the predominance of localized molecular lattice thermal expansion at high pressure.