bluuebunny/crossref_metadata_2025 huggingface dataset:
Exotic alleles contribute to heat tolerance in wheat under field conditions
Authors: Molero Gemma , Coombes Benedict , Joynson Ryan , Pinto Francisco , Piñera-Chávez Francisco J. , Rivera-Amado Carolina , Hall Anthony , Reynolds Matthew P.
Published: January 2023

Global warming poses a major threat to food security and necessitates the development of crop varieties that are resilient to future climatic instability. By evaluating 149 spring wheat lines in the field under yield potential and heat stressed conditions, we demonstrate how strategic integration of exotic material significantly increases yield under heat stress compared to elite lines, with no significant yield penalty under favourable conditions. Genetic analyses reveal three exotic-derived genetic loci underlying this heat tolerance which together increase yield by over 50% and reduce canopy temperature by approximately 2 °C. We identified anAe. tauschiiintrogression underlying the most significant of these associations and extracted the introgressedAe. tauschiigenes, revealing candidates for further dissection. Incorporating these exotic alleles into breeding programmes could serve as a pre-emptive strategy to produce high yielding wheat cultivars that are resilient to the effects of future climatic uncertainty.
Branching mechanism of photoswitching in an Fe(II) polypyridyl complex explained by full singlet-triplet-quintet dynamics
Authors: Rozgonyi Tamás , Vankó György , Pápai Mátyás
Published: January 2023

It has long been known that irradiation with visible light converts Fe(II) polypyridines from their low-spin (singlet) to high-spin (quintet) state, yet mechanistic interpretation of the photorelaxation remains controversial. Herein, we simulate the full singlet-triplet-quintet dynamics of the [Fe(terpy)2]2+ (terpy = 2,2’:6’,2”-terpyridine) complex in full dimension, in order to clarify the complex photodynamics. Importantly, we report a branching mechanism involving two sequential processes: a dominant 3MLCT→3MC(3T2g)→3MC(3T1g)→5MC, and a minor 3MLCT→3MC(3T2g)→5MC component. (MLCT = metal-to-ligand charge transfer, MC = metal-centered). While the direct 3MLCT→5MC mechanism is considered as a relevant alternative, we show that it could only be operative, and thus lead to competing pathways, in the absence of 3MC states. The quintet state is populated on the sub-picosecond timescale involving non-exponential dynamics and coherent Fe-N breathing oscillations. The results are in agreement with the available time-resolved experimental data on Fe(II) polypyridines, and fully describe the photorelaxation dynamics.
Recent advances in fluorescence chemosensors for ammonia sensing in the solution and vapor phases
Authors: Lakshmi Pandi Raja , Mohan Binduja , Kang Preeti , Nanjan Pandurangan , Shanmugaraju Sankarasekaran
Published: January 2023

In this review article, we have highlighted the recent advancements in the design of fluorescence chemosensors for sensing ammonia both in the solution and vapor phases.
Electrochemically driven [4+2] benzannulation: synthesis of polycyclic (hetero)aromatic compounds
Authors: Liu Yunlong , Zhou Pengcheng , Xu Yingli , Yang Zhiqi , Wang Dong
Published: January 2023

A green and economical electrochemical protocol has been developed to synthesize polycyclic (hetero)aromatic compounds by the [4+2] benzannulation of biaryldiazonium salts with alkynes.
Photoinduced boron atom insertion of benzocyclobutene forming an unprecedented fused boron heterocyclic radical
Authors: Xu Jiaping , Xu Xin , Li Danyang , Xie Bin-Bin , Jian Jiwen
Published: January 2023

Spectroscopic evidence of forming a fused boron heterocyclic radical through photoinduced boron atom insertion has been presented. Atom colors: B = pink; C = gray; H = white.
Initial stage of carbonization of iron during hydrocarbons dissociation: a molecular dynamics study
Authors: Liu Yubing , Yuan Xiaoze , Lu Kuan , Chen Wei , Song Yu-Fei , Yang Yong , Li Yong-Wang , Wen Xiao-Dong
Published: January 2023

This work systematically studies the carburization mechanisms of iron nanoparticles by different carbon sources, and clarifies the key influence of carbon sources on the formation of different carbides.
Ultrafast spectroscopy of RuIIpolypyridine complexes in the gas phase and the liquid phase: [Ru(2,2′-bipyridine)2(nicotinamide)2]2+
Authors: Schüssler L. , Israil R. G. E. , Hütchen P. , Thiel W. R. , Diller R. , Riehn C.
Published: January 2023

Ultrafast electronic and ligand dissociation dynamics proceeds on different time scales in the gas phase and solution phase owing to solvent-induced stabilization of charge-transfer states.
Pt38as a promising ethanol catalyst: a first principles study
Authors: Rigo Vagner Alexandre , Baletto Francesca
Published: January 2023

This first-principles study predicts Pt38nanoparticles as a promising catalyst for ethanol reactions.
A plausible investigation of low dimensional magnetism in a 3D spin system PrVO4
Authors: Ranaut Dheeraj , Mukherjee K.
Published: January 2023

Signatures of novel low dimensional magnetic ground state in 3D rare-earth orthovanadate PrVO4. The linear chains formed by Pr atoms give rise to low D quantum state, as established by various experimental probes.
Molecular dynamics study on thermal conductance between a nanotip and a substrate under vertical forces and horizontal sliding
Authors: Sun Qiangsheng , Liu Wenxiang , Huang Dezhao , Huang Xiaona , Xu Shen , Wang Jianmei , Ye Zhijiang , Wang Xiaosun , Wu Shijing , Yue Yanan
Published: January 2023

Heat transfer from a nanotip to its substrate during sliding is investigated. Larger contact forces between the probe and substrate result in enhanced interfacial thermal transport.
On the accuracy of orbital based multi-level approaches for closed-shell transition metal chemistry
Authors: Amanollahi Zohreh , Lampe Lukas , Bensberg Moritz , Neugebauer Johannes , Feldt Milica
Published: January 2023

We studied the accuracy of projection-based WFT-in-DFT embedding and LCCSD(T0):LMP2 embedding for predicting reaction energies and barriers of typical, closed-shell transition-metal-based reactions.
Interplay of molecular dynamics and radiative decay of a TADF emitter in a glass-forming liquid
Authors: Swartzfager John R. , Chen Gary , Francese Tommaso , Galli Giulia , Asbury John B.
Published: January 2023

The emissive properties of a thermally activated delayed fluorescence emitter, NAI-DMAC, are influenced by the molecular dynamics of the solvent indicating that emission involves transient access to conformations with higher radiative probabilities.
On enhancing the Li-ion conductivity of quasi-solid-state electrolytes by suppressing the flexibility of zeolitic imidazolate framework-8 via a mixed ligand strategy
Authors: Utpalla P. , Mor J. , Sharma S. K.
Published: January 2023

Li ionic conduction is decoupled from polymer segmental relaxations in PEO-ZIF QSSEs. Li ion conductivity is enhanced by tuning the pore architecture of the fillers.
Band gap and defect engineering of bismuth vanadate using La, Ce, Zr dopants to obtain a photoelectrochemical system for ultra-sensitive detection of glucose in blood serum
Authors: Prakash Jyoti , Nechiyil Divya , Ali Kawsar , Sharma Sandeep K. , Dey Anusree , Uppal Sheetal , Arya Ashok
Published: January 2023

Bismuth vanadate (BiVO4) is a promising photoactive material for the design of photoelectrochemical (PEC) analytical devices for the non-enzymatic detection of glucose.
Boosting the activity of Mizoroki–Heck cross-coupling reactions with a supramolecular palladium catalyst favouring remote Zn⋯pyridine interactions
Authors: Abuhafez Naba , Gramage-Doria Rafael
Published: January 2023

Kinetically labile Zn⋯N interactions between substrate and catalyst are responsible for the enhanced reactivity as well as substrate selectivity disclosed in a supramolecular palladium-catalyzed Mizoroki–Heck reaction between bromopyridines and olefins.
Image-based cell sorting using focused travelling surface acoustic waves
Authors: Nawaz Ahmad Ahsan , Soteriou Despina , Xu Catherine K. , Goswami Ruchi , Herbig Maik , Guck Jochen , Girardo Salvatore
Published: January 2023

Real-time morpho-rheological analysis of cells by RT-DC, combined with the improved sorting performance of an on chip FTSAW-based microactuator enables efficient label-free image-based sorting of various cell types with distinct physical properties.
Integrative analysis of small non-coding RNAs predicts a piRNA/miRNA-CCND1/BRAF/HRH1/ATXN3 regulatory circuit that drives oncogenesis in glioblastoma
Authors: Nayak Rojalin , Chattopadhyay Trisha , Gupta Pooja , Mallick Bibekanand
Published: January 2023

A model depicting activation of GPCR and Akt signalling driving oncogenesis in glioblastoma due to activation of genes - CCND1/ATXN3/BRAF/HRH1, possibly due to downregulation of the corresponding targeting miRNAs and piRNAs.
Advances in high-voltage supercapacitors for energy storage systems: materials and electrolyte tailoring to implementation
Authors: Lim Jae Muk , Jang Young Seok , Van T. Nguyen Hoai , Kim Jun Sub , Yoon Yeoheung , Park Byung Jun , Seo Dong Han , Lee Kyung-Koo , Han Zhaojun , Ostrikov Kostya (Ken) , Doo Seok Gwang
Published: January 2023

Supercapacitor is a promising energy storage device for short term energy storage system (ESSs). This review, covers materials and electrolyte tailoring needed to achieve high V supercapacitor, essential for designing an efficient short term ESSs.
Effects of relativity on the superheavy dimers M2, M = Nh–Og
Authors: Atsumi Michiko
Published: January 2023

Nh2, Fl2, Mc2, Lv2, Ts2, and Og2 are used to investigate the effects of relativity on the 7th row in the periodic table.
Computer-aided structure-based optimization of 4,5,6,7-tetrahydrobenzo[d]thiazole-2,6-diamine derivatives as DNA gyrase B inhibitors
Authors: Gutierrez Lucas J. , Vettorazzi Marcela , Dernovšek Jaka , Durcik Martina , Mašič Lucija Peterlin , Tomašič Tihomir , Enriz Ricardo D.
Published: January 2023

Here we report a theoretical-experimental study of 4,5,6,7-tetrahydrobenzo[d]thiazole-2,6-diamine derivatives that act as inhibitors of bacterial DNA gyrase B (GyrB).
1,3-Dipolar cycloaddition of cycloimmonium salts and 4-(trimethylsilyl)-3-butyn-2-one to access new functionalized indolizines with potential cytostatic activity
Authors: Zubaş Andreea , Ghinet Alina , Shova Sergiu , Bîcu Elena
Published: January 2023

4-(Trimethylsilyl)-3-butyn-2-one is an effective dipolarophile in the [3+2] cycloaddition reaction with cycloimmonium salts to obtain bioactive non-silicon adducts, namely 1-acetylindolizines, but also trimethylsilyl-containing adducts.
Nitrogen-doped fullerenes for CO2 capture: a DFT study
Authors: Anila Sebastian , Suresh Cherumuttathu H.
Published: January 2023

Molecular electrostatic potential (MESP) topology analysis reveals that nitrogen-doping improves the electron density of the carbon cage and suggests N-fullerenes and N-cyanofullerides as potent CO2 capturing agents.
Nonlinear properties of benzothiadiazole-based intramolecular charge-transfer compounds
Authors: Zhu Xiang-Zhao , Hu Hong-Dan , Chen Song-Hua , Li Yuan-Ming , Yan Jian-Feng , Yuan Yao-Feng
Published: January 2023

A benzothiadiazole-based chromophore using the molecular design strategy of engineering multipolar charge distributions was synthesized and obtained a large nonlinear response.
Introduction to engineering the biosynthesis of fungal natural products
Authors: Cox Russell J. , Gulder Tobias A. M.
Published: January 2023

Guest editors Russell Cox and Tobias Gulder introduce this Natural Products Reports themed issue summarizing recent progress in engineering the biosynthesis of fungal natural products.
Enhancing the catalytic performance of Co–N–C derived from ZIF-67 by mesoporous silica encapsulation for chemoselective hydrogenation of furfural
Authors: Zhao Jianbo , Li Xiaomeng , Zhang Meng , Xu Zhuo , Qin Xiaomei , Liu Yingfan , Han Lifeng , Li Gao
Published: January 2023

Hollow mesoporous Co–N–C@mSiO2 catalysts derived from ZIF-67 via the encapsulation–pyrolysis strategy exhibit excellent performance and good stability for furfural hydrogenation.
Pathway of transient electronics towards connected biomedical applications
Authors: Dutta Ankan , Cheng Huanyu
Published: January 2023

The review discusses triggering strategies for transient electronics. Connected biomedical applications with diagnostic and therapeutic capabilities of transient electronics have been summarized.
Towards site-specific emission enhancement of gold nanoclusters using plasmonic systems: advantages and limitations
Authors: Pavelka Ondrej , Dyakov Sergey , Kvakova Klaudia , Vesely Jozef , Cigler Petr , Valenta Jan
Published: January 2023

Enhancement of the luminescence of gold nanoclusters using gold nanorods is determined both experimentally and theoretically as a function of spacer thickness, spectral overlap, dimensions of nanorods and the specific position of nanoclusters on a nanorod.
Hybrid 2D perovskite and red emitting carbon dot composite for improved stability and efficiency of LEDs
Authors: Pannu Amandeep Singh , Sen Suvankar , Wang Xiaodong (Tony) , Jones Robert , Ostrikov Kostya (Ken) , Sonar Prashant
Published: January 2023

To improve operational stability of perovskite (PSK) LEDs, we used red-emitting hydrophobic carbon dots to impart structural stability to 2D PSK and reduce band offset, improving the operational stability of device to 8 hours from less than 2 hours.
Correction: A study on the conformation-dependent colorimetric response of polydiacetylene supramolecules to external triggers
Authors: Cingil Hande E. , Beliktay Gizem , Tan Eric M. M.
Published: January 2023

Correction for ‘A study on the conformation-dependent colorimetric response of polydiacetylene supramolecules to external triggers’ by Hande E. Cingil et al., Mater. Chem. Front., 2023, https://doi.org/10.1039/d2qm01006b.
The endophyticFusariumstrains: a treasure trove of natural products
Authors: Ahmed Arwa Mortada , Mahmoud Basma Khalaf , Millán-Aguiñaga Natalie , Abdelmohsen Usama Ramadan , Fouad Mostafa Ahmed
Published: January 2023

The complexity and structural diversity of the secondary metabolites produced by endophytes make them an attractive source of natural products with novel structures that can help in treating life-changing diseases.
Fluorescent detection of brown spot of tobacco caused by Alternaria alternata based on lambda exonuclease-induced DNAzyme amplification
Authors: Lian Kai , Chen Guangyan , Wang Xiaoqiang , Zhang Wenna , Hu Xihao , Wang Hui , Li Yusen , Xi Dongmei , Wang Ying
Published: January 2023

A rapid, simple, and sensitive fluorescent detection method for brown spot of tobacco is established by lambda exonuclease-induced Mg2+-dependent DNAzyme amplification.
Ceria-based coatings on magnesium alloys for biomedical applications: a literature review
Authors: Hernández-Montes V. , Buitrago-Sierra R. , Echeverry-Rendón Mónica , Santa-Marín J. F.
Published: January 2023

Current research trends in Mg alloys are focused on the development of smart coatings with self-healing properties that improve corrosion resistance of these alloys. Ceria based materials have recently emerged as materials that can be used as smart coatings on Mg alloys.
High capacity and fast removal of Cr(vi) by alkali lignin-based poly(tetraethylene pentamine-pyrogallol) sorbent
Authors: Xing Rufei , Song Yanxin , Gao Tingting , Cai Xiaoxia , Yao Jinshui , Liu Qinze , Zhang Changbin
Published: January 2023

The alkali lignin-based poly(tetraethylene pentamine-pyrogallol) (AL-PTAP) was prepared with an adsorption capacity of 769.2 mg g−1 and a removal percentage of almost 100% within 1 min at an initial concentration of less than 90 mg L−1.
Navigating the interlanguage space: Chinese international students’ perceptions of a virtual chemistry laboratory course
Authors: Lee Eshani N. , Nealy Schetema , Cruz Laura
Published: January 2023

The unforeseen shift to virtual learning during the COVID-19 pandemic required instructors and students to face unprecedented learning challenges. Under these circumstances, Chinese international students who intended to come to the U.S. to begin their studies were required to remotely access their courses while still residing in China, which included a general chemistry laboratory course. Research suggests that English language learners (ELL) face a substantial language barrier in science-based courses as they must simultaneously be proficient in English as well as in the discipline-specific academic language; however, little is understood about how ELLs navigate these challenges in the context of a virtual chemistry laboratory course. This study examined the perceptions of Chinese international students about their learning as well as the tools/strategies they used to navigate the language barrier in the virtual laboratory course. Results suggest that although the participants perceived the virtual laboratory space as a safe and low-pressured environment to run experiments, they experienced difficulties in comprehending procedures adequately which potentially hindered them from developing a deeper understanding of the experiments. The types of strategies and tools that students used to navigate between their first language, the English language, and the academic language associated with chemistry mainly supported surface level learning. These findings underscore the need to identify and develop more sophisticated instructional strategies that help students navigate interlanguage spaces and reach higher levels of learning.
Revealing the development of interaction among components of pedagogical content knowledge in teaching chemical equilibrium
Authors: Oztay Elif Selcan , Ekiz-Kiran Betul , Boz Yezdan
Published: January 2023

This study aimed to capture the development of interaction among the components of pre-service chemistry teachers’ enacted PCK throughout the school experience course. Data were collected from four pre-service teachers using content representation (CoRe), observations, field notes, and semi-structured interviews. Secondary analysis was conducted by re-analyzing the pre-existing data for the previous study (Ekiz-Kiran B., Boz Y. and Oztay E. S., (2021), Development of pre-service teachers’ pedagogical content knowledge through a PCK-based school experience course, Chem. Educ. Res. Pract., 22(2), 415–430.) from a different perspective to find out the interaction among the components of pre-service chemistry teachers’ enacted PCK. In order to analyze data, we used three approaches: an in-depth analysis of explicit PCK, an enumerative approach, and the constant comparative method. Results were presented as PCK maps, and results indicated that the development of the integration of the PCK components was idiosyncratic. Moreover, the most significant development was seen in the connections between knowledge of curriculum and other components, especially knowledge of assessment. Additionally, knowledge of instructional strategy (KoIS) was the most frequently integrated component with the other PCK components. Implications for research and science teacher education are included.
Metal–organic framework-derived Co single atoms anchored on N-doped hierarchically porous carbon as a pH-universal ORR electrocatalyst for Zn–air batteries
Authors: Li Le , Li Na , Xia Jiawei , Zhou Shilong , Qian Xingyue , Yin Fengxiang , He Guangyu , Chen Haiqun
Published: January 2023

Co-SAs/N-C/rGO catalyst with atomic CoN4 moiety manifests exceptional ORR activity in pH-universal media.
State of the art in the photochemical degradation of (micro)plastics: from fundamental principles to catalysts and applications
Authors: Li Wenxi , Zhao Wenxuan , Zhu Haoyu , Li Zhi-Jun , Wang Wanglei
Published: January 2023

Plastics and microplastics are major environmental pollutants due to wide applications and difficult degradations. Herein, we summarize several studies on degradations of (micro)plastics to value-added products and intermediatesviaphotocatalysis.
Highly stretchable porous regenerated silk fibroin film for enhanced wound healing
Authors: Sun Fengchao , Xiao Dongdong , Su Hui , Chen Zhiliang , Wang Bijia , Feng Xueling , Mao Zhiping , Sui Xiaofeng
Published: January 2023

Silk fibroin (SF) has caught interest in tissue engineering owing to their biocompatibility and biodegradability.
3D printed reduced graphene oxide-GelMA hybrid hydrogel scaffolds for potential neuralized bone regeneration
Authors: Zhang Xinwei , Zhang Hao , Zhang Yi , Huangfu Huimin , Yang Yixin , Qin Qiuyue , Zhang Yidi , Zhou Yanmin
Published: January 2023

A biomaterial scaffold capable of simultaneously loading multiple stem cells for potential neuralized bone regeneration.
A multi-site recognition molecularly imprinted solid-phase microextraction fiber for selective enrichment of three cross-class environmental endocrine disruptors
Authors: Duan Yunli , Xu Zhigang , Liu Zhimin
Published: January 2023

A multi-site recognition MIP fiber for cross-class EED enrichment.
Enhanced energy transfer by Sb ion doping for efficient CsPbCl3:Mn2+perovskite nanocrystals and light emitting diodes
Authors: Wang Nan , Sun Rui , Xu Wen , Bai Xue , Hu Junhua , Lu Siyu , Zhou Donglei , Song Hongwei
Published: January 2023

In CsPbCl3:Mn2+, Sb3+NCs, Sb3+acts as an intermediate energy level between the CsPbCl3NC matrix and Mn2+, which greatly improves the PLQY of Mn2+.
Regulating the photoluminescence and energy transfer process of Sr5(PO4)3Cl:Eu2+, Mn2+ via pressure-induced phase transition
Authors: Liu Ke , Wen Ting , Li Chen , Ma Yingying , Jiang Dequan , Yue Binbin , Wang Yonggang
Published: January 2023

Regulation of the energy transfer between Eu2+ and Mn2+ ions, and the photoluminescence properties with pressure.
Color-tunable and ultralong organic room temperature phosphorescence from poly(acrylic acid)-based materials through hydrogen bond engineering
Authors: Kong Liuqi , Zhu Yan , Sun Shaochen , Li Hongye , Tao Farong , Li Fei , Wang Liping , Li Guang
Published: January 2023

A series of poly(acrylic acid) (PAA)-based RTP materials with ultralong lifetimes were prepared by a facile binary doping strategy, and two PAA-based RTP materials displayed amazing color-tunability through a variety of stimuli.
Constructing a desired nanofibril network morphology for stretchable polymer films by weakening the intermolecular interaction of a conjugated polymer in an elastomer matrix and extending the film-forming time
Authors: Zhang Tao , Liu Yadi , Zhang Lu , Wang Sichun , Li Junhang , Zuo Jiaming , Yu Xinhong , Zhang Qiang , Han Yanchun
Published: January 2023

Low Ra(b) solvent o-DCB weakens intermolecular interactions of N2200 in the SEBS matrix, leading to the formation of a nanofibril network morphology with a small fibril size (<45 nm), which greatly improves the stretchability of the blend film.
In situphotogenerated hydroxyl radicals in the reaction atmosphere for the accelerated crystallization of solution-processed functional metal oxide thin films
Authors: Gómez-Lopez Alicia , Rivas Y. Andrea , López-Fajardo Sergio , Jiménez Ricardo , Ricote Jesús , Pecharromán Carlos , Montero Isabel , Bretos Iñigo , Calzada M. Lourdes
Published: January 2023

We propose a disruptive method to accelerate the crystallization at low temperatures of functional metal oxide films whereby hydroxyl radicals (•OH) are photogeneratedin situfrom the atmosphere where solution-deposited layers are UV-irradiated.
Sulfonated polythiophene-interfaced graphene for water-redispersible graphene powder with high conductivity and electrocatalytic activity
Authors: Tran Tuan Sang , Balu Rajkamal , de Campo Liliana , Dutta Naba Kumar , Choudhury Namita Roy
Published: January 2023

The surface of pristine graphene is engineered toward hydrophilicity by interfacing with amphiphilic PTEBS molecules, creating a new class of water-redispersible graphene with high conductivity and electrocatalytic activity for energy applications.
Free-standing graphene oxide/oxidized carbon nanotube films with mixed proton and electron conductor properties
Authors: Rabin Nurun Nahar , Islam Md. Saidul , Rahman Mohammad Atiqur , Tagawa Ryuta , Shudo Yuta , Sekine Yoshihiro , Hayami Shinya
Published: January 2023

A free-standing film of graphene oxide and oxidized single-wall carbon nanotubes showing efficient mixed proton and electron conduction at room temperature is demonstrated.
Multiple extended target tracking based on distributed multi‐sensor fusion and shape estimation
Authors: Yang Jinlong , Xu Mengfan , Liu Jianjun , Li Fangdi
Published: January 2023

Distributed multi‐sensor fusion based on the generalised covariance intersection (GCI) fusion has been widely integrated into the Random Finite Set theory, which is promising for multi‐target tracking with an unknown number of targets. However, it has not been widely investigated in the multiple extend target tracking (METT) field, and there is still an open problem on how to solve the inconsistency of label space among the sensors. For these problems, we first introduce the GCI fusion into the METT and proposed an association algorithm by considering the estimated shapes and the target positions to avoid the phenomenon of the label inconsistency as well as to reduce the computational burden. Simulation results show that the proposed algorithm has a better tracking performance than the traditional METT algorithms.
Robust direct acoustic impedance control using two microphones for mixed feedforward-feedback controller
Authors: Volery Maxime , Guo Xinxin , Lissek Hervé
Published: January 2023

This paper presents an acoustic impedance control architecture for an electroacoustic absorber combining both feedforward and feedback microphone-based strategies on a current-driven loudspeaker. Feedforward systems enable good performance for direct impedance control. However, inaccuracies in the required actuator model can lead to a loss of passivity, which can cause unstable behaviour. The feedback contribution allows the absorber to better handle model errors and still achieve an accurate impedance, preserving passivity. Numerical and experimental studies were conducted to compare this new architecture against a state-of-the-art feedforward control method.
A method of controlling the imprint effect in hafnia ferroelectric device
Authors: Shin Hunbeom , Gaddam Venkateswarlu , Goh Youngin , Jeong Yeongseok , Kim Giuk , Qin Yixin , Jeon Sanghun
Published: January 2023

Recently, hafnia-based ferroelectrics are currently being investigated as next-generation memory devices due to their excellent CMOS process compatibility and functionality. However, some of the ferroelectric devices commonly exhibit an imprint effect due to charged defects around the interfacial layer, which has negative impacts on the ferroelectric memory devices. However, it can be applied to various applications as long as the imprint field is carefully adjusted. In this work, we introduced a strategy to control the imprint field in bilayer capacitors by utilizing tantalum oxide (TaO) interfacial layers and various Zr contents in Hf0.83Zr0.17O2 (HZO) films. The TaO layer (1 nm) was inserted into the bilayer capacitors to alter the imprint field's (positive or negative) direction. Whereas to control the imprint fields, we adjusted the Zr doping content (17%–83%) in the ferroelectric HZO films (8 nm). As the Zr content increased, reduced imprint fields were observed in those bilayer capacitors. In addition, it was found that a high imprint field (+2.43 MV/cm) was observed in Hf-rich films (Hf0.83Zr0.17O2) due to the higher amount of oxygen vacancies. In addition, we examined those oxygen vacancies through x-ray photoelectron spectroscopy depth profile analysis by considering sub-oxide fractions in the tantalum, which further confirms the root cause of the imprint field variations in the bilayer capacitors. Our study will contribute to a deeper understanding of imprinted hafnia-based ferroelectrics and will provide an insight into devices that utilize the imprint effect.
Weak antilocalization and ferromagnetism in magnetic Weyl semimetal Co3Sn2S2
Authors: Kumar Kapil , Sharma M. M. , Awana V. P. S.
Published: January 2023

Here, we report the synthesis of single crystalline magnetic Weyl semimetal Co3Sn2S2. The synthesized crystal is characterized through various tools, viz. x-ray diffraction, field emission electron microscopy, and x-ray photoelectron spectroscopy. A clear ferromagnetic transition is observed in magnetization and heat capacity at around 175 K, which is further verified through electrical transport measurements. Hysteresis is observed in ρ–T measurements in a cooling and a warming cycle, showing the presence of the first order phase transition and charge ordering in the synthesized sample. Synthesized Co3Sn2S2 exhibits a high magnetoresistance of around 230% at 2 K. The transport phenomenon in synthesized Co3Sn2S2 appears to have contributions from topological surface states at low temperature below, say, 70 K, and above that, the same is found to be strongly dependent on its bulk magnetic state. Magnetoconductivity data at low fields of up to ±1 T (Tesla) are fitted with the Hikami Larkin Nagaoka model, which shows the presence of a weak antilocalization (WAL) effect in the synthesized Co3Sn2S2 crystal at low temperatures below 30 K. Angle dependent magnetotransport measurements confirm that the observed WAL is the topological surface state dominated phenomenon.
Coherent structures, turbulence intermittency, and anisotropy of gravity currents propagating on a rough and porous bed
Authors: Han Dongrui , Guo Yakun , Jiao Pengcheng , Yuan Yeping , Lin Ying-Tien , He Zhiguo
Published: January 2023

This study experimentally investigated the impacts of rough and porous (RP) bed and sedimentation processes on the coherent structures, turbulence intermittency, and anisotropy of saline and turbidity currents. The results reveal that the local current concentration responds immediately (saline current) or languidly (turbidity current) to turbulence bursting events. Inside the dense current, the turbulent momentum fluxes in the streamwise (u′u′¯) and vertical (w′w′¯) directions transfer downstream and downward, which favor the sweep events. Inside the ambient water, u′u′¯ and w′w′¯ transfer upstream and upward, contributing to the formation of ejection events. At the current–ambient water interface, u′u′¯ and w′w′¯ do not tend to transfer in particular directions resulting in almost equal quantities of sweep and ejection events. The Gram–Charlier series expansion is strictly applicable to probability density functions (PDFs) of the sweep and ejection events but not suitable ideally for PDFs of the outward and inward interaction events. The primary anisotropy invariant map (AIM) of gravity currents starts from the two-component plain strain limit (near the bed). It is followed by the three-dimensional isotropy (inside the dense current and ambient water) and the axisymmetric contraction limit (current–ambient water interface). Finally, it ends in two-dimensional isotropy (near the free surface). This AIM is sensitive to the RP boundary and the sedimentation processes. Along the streamwise direction, the RP boundary causes alternations between the anisotropic and isotropic turbulence, but the arranged pattern of the rough units determines the period of this alternation.
Rarefied gas effects on hypersonic flow over a transpiration-cooled flat plate
Authors: Appar Ahilan , Bajpai Aasheesh , Sivakumar Udhaya K. , Naspoori Srujan K. , Kumar Rakesh
Published: January 2023

This paper presents the effect of blowing (transpiration flow) on hypersonic flow over a flat plate at different flow regimes. The investigation involves the study of the interaction between the free stream flow of argon gas at Mach 5 and transpiring gas introduced at the fluid–solid interface. The freestream Knudsen number considered for the present analysis are 0.002, 0.01, 0.05, and 0.25, extending from continuum to rarefied through transitional flow conditions. Flow simulations are performed using the open source particle-based direct simulation Monte Carlo (DSMC) solver called Stochastic PArallel Rarefied-gas Time-accurate Analyzer (SPARTA). In the DSMC framework, the transpiring gases are introduced as jets with specified velocity, number density, and temperature uniformly throughout the surface in the direction normal to the surface. The variation in flow field properties, such as density, temperature, and velocity with and without transpiration, is studied. The influence of rarefaction on surface heat flux distribution is studied at different flow Knudsen numbers. Furthermore, the effect of introducing the transpiring gas at different densities into the flow field is investigated and its impact on the surface heat flux is discussed. It is interesting to note that in certain cases, the heat flux actually increases locally as a result of the interaction between transpiring gas and freestream flow.
Observation of localized acoustic skyrmions
Authors: Hu Ping , Wu Hong-Wei , Sun Wen-Jun , Zhou Nong , Chen Xue , Yang Yong-Qiang , Sheng Zong-Qiang
Published: January 2023

Recently, acoustic skyrmions have been explored by tailoring velocity vectorial near-field distributions based on the interference of multiple spoof surface acoustic waves, providing new dimensions for advanced sound information processing, transport, and data storage. Here, we theoretically investigate and experimentally demonstrate that a deep-subwavelength spiral metastructure can also generate the acoustic skyrmion configuration. Analyzing the resonant response of the metastructure and observing the spatial profile of the velocity field, we find that the localized skyrmionic modes correspond to eigenmodes of the spiral structure. Thus, the skyrmionic modes do not require carefully tailored external excitation condition and they have multiple resonating frequencies unlike the single skyrmionic mode realized by the interference of multiple waves. We also demonstrate that the topological protected skyrmions supported by the subwavelength metastructure is robust against structure deformations and existence of structure defects. The real-space acoustic skyrmion topology may open new avenues for designing ultra-compact and robust acoustic devices, such as acoustic sensors, acoustic tweezers, and acoustic antennas.
Chemical and electronic properties of interfaces between RuO2 and Hf0.5Zr0.5O2 studied by x-ray photoelectron spectroscopy
Authors: Chernikova Anna G. , Lebedinskii Yury Yu. , Khakimov Roman R. , Markeev A. M.
Published: January 2023

Recently, the extensive study of the platinum group metal oxide electrodes for TiN replacement in Hf0.5Zr0.5O2 (HZO)-based ferroelectric memory stacks began. In this work, we use high sensitivity of x-ray photoelectron spectroscopy to the interface chemical and electronic states to investigate the chemistry and band alignment between HZO and RuO2, which is one of the most suitable noble metal oxide electrodes. We report that RuO2 is easily reduced to metallic Ru during the atomic layer deposition (ALD) of HZO because of the chemical reaction between the oxygen stored in RuO2 and metallic precursors used for HZO deposition. This process makes it impossible to use RuO2 as a bottom electrode, when HZO is grown by the conventional thermal ALD process (with H2O as a reactant). At the same time, RuO2 may be effectively conserved if one uses more active oxygen reactants for the HZO growth because of the re-oxidation of the newly formed Ru. RuO2 is also effectively conserved at the top interface, at least within the thermal budget of the growth of all functional layers. We also report the detailed investigation of the band alignment between RuO2 and HZO in both type of stacks (with reduced and conserved RuO2) and both interfaces with HZO (top and bottom), which may be useful for the understanding of the ferroelectric properties of the related stacks in the future. In addition, the potential of RuO2 utilization for the reliability improvement of HZO-based stacks is discussed.
Revealing spin-valve-like and exchange bias effect in Co3Sn1.9In0.1S2 crystal
Authors: Roychowdhury A. , Ghose P. K. , Dalui T. K. , Majumdar S. , Giri S.
Published: January 2023

We report on sharp spin-valve-like magnetoresistance (MR) below ferromagnetic order (TC), which has not been discussed in the pristine as well as doped crystals. In addition, typical manifestation of exchange bias (EB) effect is also observed by systematic shifts of the loop observed in MR driven by the cooling field. The EB effect appears below a characteristic temperature (TA), below which ferromagnetic and antiferromagnetic phases have been suggested to coexist. As a result of In doping, the sharp spin-valve-like evidence and EB effect over a wide temperature range, which are observed even at much higher temperatures than the liquid nitrogen temperature, suggest the system as a potential candidate for application in topological spintronics.
Generation of the small tin-droplet streams with a manipulable droplet spacing via the forced velocity perturbation
Authors: Jun Luo , Shengnan Lyu , Lehua Qi , Ni Li
Published: January 2023

In extreme ultraviolet (EUV) sources, small tin droplets are scattered into the tin mist/disk under the irradiation of the pulsed laser to produce the EUV light. Small droplet size and large droplet spacing are required to suppress debris production to protect expensive collector mirrors. To this end, a tin-droplet generator with a capillary glass nozzle was designed and built to produce uniform tin-droplet streams with the droplet diameter less than 50 μm. Meanwhile, a forced perturbation, generated by a sandwich piezoelectric transducer, was loaded into a liquid tin jet to manipulate the droplet spacing through a stepped rod. The mono-sized tin-droplet streams with an average diameter of 42 μm were successfully produced in both the Rayleigh and the forced jet breakup regimes. A two-dimensional (2D) axisymmetric model was proposed to reveal the influence of the velocity perturbation amplitude on jet breakup patterns at different wavelengths. An F*–λ* (The dimensionless perturbation velocity amplitude F*–The dimensionless wavenumber l*) map was built, and five different droplet breakup patterns were identified based on simulations. Numerical simulations indicated that the droplet spacing could be increased by providing extra momentum to droplets from the forced velocity perturbation. Finally, by increasing the velocity perturbation amplitude, the droplet spacing was increased from ∼9Dd (droplet diameter) to ∼19Dd without significantly increasing the droplet size. This work provides a novel approach to obtaining small mono-sized tin-droplet streams with manipulable droplet spacing.
Laser-induced deep-subwavelength periodic nanostructures with large-scale uniformity
Authors: Geng Jiao , Shi Liping , Liu Jukun , Xu Liye , Yan Wei , Qiu Min
Published: January 2023

Femtosecond lasers are capable of fabricating uniform periodic nanostructures with a near-wavelength periodicity; however, it is challenging to produce subwavelength nanostructures with large-scale uniformity. Here, we investigate femtosecond laser-induced self-assembly of periodic nanostructures on Si-on-Pt hybrid ultrathin films via photothermal-induced oxidation. The coexistence of scattering light and surface plasmon polaritons on the hybrid films gives rise to a diversity of surface morphologies. Depending on the laser power and sample scanning velocity, beyond the traditional one-dimensional nanogratings that exhibit a near-wavelength periodicity, two types of nanostructures with subdiffraction-limit periodicity while large-scale uniformity are also observed. The first type, occurring at high laser energy and low scanning velocity, is generated by the spatial frequency doubling of the traditional laser-plasmon-interfering nanogratings. It exhibits a periodicity of <λ2. The second type, deep-subwavelength nanostructures, takes place at low pulse energy or low scanning velocity. It is in the form of two-dimensional nanoparticles and has a periodicity of <λ4. The far-field laser-plasmon interference associated with near-field scattering is attributed to the formation of such deep-subwavelength nanostructures, as confirmed by finite-difference time-domain numerical simulations. Our work provides a route toward high-throughput laser fabrication of large-scale deep-subwavelength periodic nanostructures.
Social stress-induced serotonin dysfunction activates spexin in male Nile tilapia (
Oreochromis Niloticus
)
Authors: Lim Chor Hong , Soga Tomoko , Parhar Ishwar S.
Published: January 2023

Social disturbance in interpersonal relationships is the primary source of stress in humans. Spexin (SPX, SPX1a in cichlid), an evolutionarily conserved neuropeptide with diverse physiological functions, is up-regulated in the brain during chronic social defeat stress in teleost. On the other hand, repeated exposure to social stress can lead to dysregulation of the monoaminergic system and increase the vulnerability of developing depression. Since dysfunction of the serotonin (5-hydroxytryptamine, 5-HT) system is associated with social stress and the pathophysiology of depression, the present study investigated the regulatory relationship between the central 5-HT system and SPX1a in the male teleost, Nile tilapia (
Oreochromis niloticus
). To identify stress factors that regulate SPX1a gene expression, cortisol, dexamethasone (DEX), and 5-HT were used to treat tilapia brain primary cultures. Our study shows cortisol and DEX treatment had no effect on SPX1a gene expression, but SPX1a gene expression was down-regulated following 5-HT treatment. Anatomical localization showed a close association between 5-HT immunoreactive projections and SPX1a neurons in the semicircular torus. In addition, 5-HT receptors (5-HT2B) were expressed in SPX1a neurons. SPX1a immunoreactive neurons and SPX1a gene expression were significantly increased in socially defeated tilapia. On the other hand, citalopram (antidepressant, 5-HT antagonist) treatment to socially defeated tilapia normalized SPX1a gene expression to control levels. Taken together, the present study shows that 5-HT is an upstream regulator of SPX1a and that the inhibited 5-HT activates SPX1a during social defeat.
Community-engaged ancient DNA project reveals diverse origins of 18th-century African descendants in Charleston, South Carolina
Authors: Fleskes Raquel E. , Cabana Graciela S. , Gilmore Joanna K. , Juarez Chelsey , Karcher Emilee , Oubré La’Sheia , Mishoe Grant , Ofunniyin Ade A. , Schurr Theodore G.
Published: January 2023

In this study, we present the results of community-engaged ancient DNA research initiated after the remains of 36 African-descended individuals dating to the late 18th century were unearthed in the port city of Charleston, South Carolina. The Gullah Society of Charleston, along with other Charleston community members, initiated a collaborative genomic study of these ancestors of presumed enslaved status, in an effort to visibilize their histories. We generated 18 low-coverage genomes and 31 uniparental haplotypes to assess their genetic origins and interrelatedness. Our results indicate that they have predominantly West and West-Central African genomic ancestry, with one individual exhibiting some genomic affiliation with populations in the Americas. Most were assessed as genetic males, and no autosomal kin were identified among them. Overall, this study expands our understanding of the colonial histories of African descendant populations in the US South.
Disentangling the causes of mumps reemergence in the United States
Authors: Gokhale Deven V. , Brett Tobias S. , He Biao , King Aaron A. , Rohani Pejman
Published: January 2023

Over the past two decades, multiple countries with high vaccine coverage have experienced resurgent outbreaks of mumps. Worryingly, in these countries, a high proportion of cases have been among those who have completed the recommended vaccination schedule, raising alarm about the effectiveness of existing vaccines. Two putative mechanisms of vaccine failure have been proposed as driving observed trends: 1) gradual waning of vaccine-derived immunity (necessitating additional booster doses) and 2) the introduction of novel viral genotypes capable of evading vaccinal immunity. Focusing on the United States, we conduct statistical likelihood-based hypothesis testing using a mechanistic transmission model on age-structured epidemiological, demographic, and vaccine uptake time series data. We find that the data are most consistent with the waning hypothesis and estimate that 32.8% (32%, 33.5%) of individuals lose vaccine-derived immunity by age 18 y. Furthermore, we show using our transmission model how waning vaccine immunity reproduces qualitative and quantitatively consistent features of epidemiological data, namely 1) the shift in mumps incidence toward older individuals, 2) the recent recurrence of mumps outbreaks, and 3) the high proportion of mumps cases among previously vaccinated individuals.
Sensitive bacterial V
m
sensors revealed the excitability of bacterial V
m
and its role in antibiotic tolerance
Authors: Jin Xin , Zhang Xiaowei , Ding Xuejing , Tian Tian , Tseng Chao-Kai , Luo Xinwei , Chen Xiao , Lo Chien-Jung , Leake Mark C. , Bai Fan
Published: January 2023

As an important free energy source, the membrane voltage (V
m
) regulates many essential physiological processes in bacteria. However, in comparison with eukaryotic cells, knowledge of bacterial electrophysiology is very limited. Here, we developed a set of novel genetically encoded bacterial V
m
sensors which allow single-cell recording of bacterial V
m
dynamics in live cells with high temporal resolution. Using these new sensors, we reveal the electrically “excitable” and “resting” states of bacterial cells dependent on their metabolic status. In the electrically excitable state, frequent hyperpolarization spikes in bacterial V
m
are observed, which are regulated by Na
+
/K
+
ratio of the medium and facilitate increased antibiotic tolerance. In the electrically resting state, bacterial V
m
displays significant cell-to-cell heterogeneity and is linked to the cell fate after antibiotic treatment. Our findings demonstrate the potential of our newly developed voltage sensors to reveal the underpinning connections between bacterial V
m
and antibiotic tolerance.
Tropical forests post-logging are a persistent net carbon source to the atmosphere
Authors: Mills Maria B. , Malhi Yadvinder , Ewers Robert M. , Kho Lip Khoon , Teh Yit Arn , Both Sabine , Burslem David F. R. P. , Majalap Noreen , Nilus Reuben , Huaraca Huasco Walter , Cruz Rudi , Pillco Milenka M. , Turner Edgar C. , Reynolds Glen , Riutta Terhi
Published: January 2023

Logged and structurally degraded tropical forests are fast becoming one of the most prevalent land-use types throughout the tropics and are routinely assumed to be a net carbon sink because they experience rapid rates of tree regrowth. Yet this assumption is based on forest biomass inventories that record carbon stock recovery but fail to account for the simultaneous losses of carbon from soil and necromass. Here, we used forest plots and an eddy covariance tower to quantify and partition net ecosystem CO
2
exchange in Malaysian Borneo, a region that is a hot spot for deforestation and forest degradation. Our data represent the complete carbon budget for tropical forests measured throughout a logging event and subsequent recovery and found that they constitute a substantial and persistent net carbon source. Consistent with existing literature, our study showed a significantly greater woody biomass gain across moderately and heavily logged forests compared with unlogged forests, but this was counteracted by much larger carbon losses from soil organic matter and deadwood in logged forests. We estimate an average carbon source of 1.75 ± 0.94 Mg C ha
−1
yr
−1
within moderately logged plots and 5.23 ± 1.23 Mg C ha
−
1
yr
−
1
in unsustainably logged and severely degraded plots, with emissions continuing at these rates for at least one-decade post-logging. Our data directly contradict the default assumption that recovering logged and degraded tropical forests are net carbon sinks, implying the amount of carbon being sequestered across the world’s tropical forests may be considerably lower than currently estimated.