bluuebunny/crossref_metadata_2025 huggingface dataset:
Identification of robust and reproducible CT‐texture metrics using a customized 3D‐printed texture phantom
Authors: Varghese Bino A. , Hwang Darryl , Cen Steven Y. , Lei Xiaomeng , Levy Joshua , Desai Bhushan , Goodenough David J. , Duddalwar Vinay A.
Published: January 2021

Objective

The objective of this study was to evaluate the robustness and reproducibility of computed tomography‐based texture analysis (CTTA) metrics extracted from CT images of a customized texture phantom built for assessing the association of texture metrics to three‐dimensional (3D) printed progressively increasing textural heterogeneity.

Materials and Methods

A custom‐built 3D‐printed texture phantom comprising of six texture patterns was used to evaluate the robustness and reproducibility of a radiomics panel under a variety of routine abdominal imaging protocols. The phantom was scanned on four CT scanners (Philips, Canon, GE, and Siemens) to assess reproducibility. The robustness assessment was conducted by imaging the texture phantom across different CT imaging parameters such as slice thickness, field of view (FOV), tube voltage, and tube current for each scanner. The texture panel comprised of 387 features belonging to 15 subgroups of texture extraction methods (e.g., Gray‐level Co‐occurrence Matrix: GLCM). Twelve unique image settings were tested on all the four scanners (e.g., FOV125). Interclass correlation two‐way mixed with absolute agreement (ICC3) was used to assess the robustness and reproducibility of radiomic features. Linear regression was used to test the association between change in radiomic features and increased texture heterogeneity. Results were summarized in heat maps.

Results

A total of 5612 (23.2%) of 24 090 features showed excellent robustness and reproducibility (ICC ≥ 0.9). Intensity, GLCM 3D, and gray‐level run length matrix (GLRLM) 3D features showed best performance. Among imaging variables, changes in slice thickness affected all metrics more intensely compared to other imaging variables in reducing the ICC3. From the analysis of linear trend effect of the CTTA metrics, the top three metrics with high linear correlations across all scanners and scanning settings were from the GLRLM 2D/3D and discrete cosine transform (DCT) texture family.

Conclusion

The choice of scanner and imaging protocols affect texture metrics. Furthermore, not all CTTA metrics have a linear association with linearly varying texture patterns.
Trajectory log analysis and cone‐beam CT‐based daily dose calculation to investigate the dosimetric accuracy of intensity‐modulated radiotherapy for gynecologic cancer
Authors: Utena Yohei , Takatsu Jun , Sugimoto Satoru , Sasai Keisuke
Published: January 2021

This study evaluated unexpected dosimetric errors caused by machine control accuracy, patient setup errors, and patient weight changes/internal organ deformations. Trajectory log files for 13 gynecologic plans with seven‐ or nine‐beam dynamic multileaf collimator (MLC) intensity‐modulated radiation therapy (IMRT), and differences between expected and actual MLC positions and MUs were evaluated. Effects of patient setup errors on dosimetry were estimated by in‐house software. To simulate residual patient setup errors after image‐guided patient repositioning, planned dose distributions were recalculated (blurred dose) after the positions were randomly moved in three dimensions 0–2 mm (translation) and 0°–2° (rotation) 28 times per patient. Differences between planned and blurred doses in the clinical target volume (CTV) D98% and D2% were evaluated. Daily delivered doses were calculated from cone‐beam computed tomography by the Hounsfield unit‐to‐density conversion method. Fractional and accumulated dose differences between original plans and actual delivery were evaluated by CTV D98% and D2%. The significance of accumulated doses was tested by the paired t test. Trajectory log file analysis showed that MLC positional errors were −0.01 ± 0.02 mm and MU delivery errors were 0.10 ± 0.10 MU. Differences in CTV D98% and D2% were <0.5% for simulated patient setup errors. Differences in CTV D98% and D2% were 2.4% or less between the fractional planned and delivered doses, but were 1.7% or less for the accumulated dose. Dosimetric errors were primarily caused by patient weight changes and internal organ deformation in gynecologic radiation therapy.
Gradient of brain mosaic RHEB variants causes a continuum of cortical dysplasia
Authors: Lee Wei Shern , Baldassari Sara , Chipaux Mathilde , Adle‐Biassette Homa , Stephenson Sarah E. M. , Maixner Wirginia , Harvey A. Simon , Lockhart Paul J. , Baulac Stéphanie , Leventer Richard J.
Published: January 2021

Focal cortical dysplasia (FCD) and hemimegalencephaly (HME) are related malformations with shared etiologies. We report three patients with a spectrum of cortical malformations associated with pathogenic brain‐specific somatic Ras homolog enriched in brain (RHEB) variants. The somatic variant load directly correlated with the size of the malformation, with upregulated mTOR activity confirmed in dysplastic tissues. Laser capture microdissection showed enrichment of RHEB variants in dysmorphic neurons and balloon cells. Our findings support the role of RHEB in a spectrum of cortical malformations confirming that FCD and HME represent a disease continuum, with the extent of dysplastic brain directly correlated with the somatic variant load.
Multivariable Modeling of Biomarker Data From the Phase I Foundation for the National Institutes of Health Osteoarthritis Biomarkers Consortium
Authors: Hunter David J. , Deveza Leticia A. , Collins Jamie E. , Losina Elena , Katz Jeffrey N. , Nevitt Michael C. , Lynch John A. , Roemer Frank W. , Guermazi Ali , Bowes Michael A. , Dam Erik B. , Eckstein Felix , Kwoh C. Kent , Hoffmann Steve , Kraus Virginia B.
Published: January 2021

Objective

To determine the optimal combination of imaging and biochemical biomarkers for use in the prediction of knee osteoarthritis (OA) progression.

Methods

The present study was a nested case–control trial from the Foundation of the National Institutes of Health OA Biomarkers Consortium that assessed study participants with a Kellgren/Lawrence grade of 1–3 who had complete biomarker data available (n = 539 to 550). Cases were participants’ knees that had radiographic and pain progression between 24 and 48 months compared to baseline. Radiographic progression only was assessed in secondary analyses. Biomarkers (baseline and 24‐month changes) that had a P value of <0.10 in univariate analysis were selected, including quantitative cartilage thickness and volume on magnetic resonance imaging (MRI), semiquantitative MRI markers, bone shape and area, quantitative meniscal volume, radiographic progression (trabecular bone texture [TBT]), and serum and/or urine biochemical markers. Multivariable logistic regression models were built using 3 different stepwise selection methods (complex models versus parsimonious models).

Results

Among baseline biomarkers, the number of locations affected by osteophytes (semiquantitative), quantitative central medial femoral and central lateral femoral cartilage thickness, patellar bone shape, and semiquantitative Hoffa‐synovitis predicted OA progression in most models (C statistic 0.641–0.671). In most models, 24‐month changes in semiquantitative MRI markers (effusion‐synovitis, meniscal morphologic changes, and cartilage damage), quantitative central medial femoral cartilage thickness, quantitative medial tibial cartilage volume, quantitative lateral patellofemoral bone area, horizontal TBT (intercept term), and urine N‐telopeptide of type I collagen predicted OA progression (C statistic 0.680–0.724). A different combination of imaging and biochemical biomarkers (baseline and 24‐month change) predicted radiographic progression only, which had a higher C statistic of 0.716–0.832.

Conclusion

The present study highlights the combination of biomarkers with potential prognostic utility in OA disease‐modifying trials. Properly qualified, these biomarkers could be used to enrich future trials with participants likely to experience progression of knee OA.
Differential Impact of Fluid Shear Stress and YAP/TAZ on BMP/TGF‐β Induced Osteogenic Target Genes
Authors: Reichenbach Maria , Mendez Paul‐Lennard , da Silva Madaleno Carolina , Ugorets Vladimir , Rikeit Paul , Boerno Stefan , Jatzlau Jerome , Knaus Petra
Published: January 2021

Bone is a remarkable dynamic structure, which integrates mechanical and biochemical signaling inputs. Interstitial fluid in the intramedullary space transmits signals derived from compression‐induced fluid shear stress (FSS) to stimulate osteoblasts for bone formation. Using a flow system and human osteoblasts, this study demonstrates how BMP/TGF‐β  signaling integrates stimuli derived from FSS and YAP/TAZ and confirms these findings by transcriptome analyses. Here, FSS positively affects the phosphorylation of both SMAD1/5 and SMAD2/3, the respective BMP‐ and TGFβ‐R‐SMADs. Increase in phosphorylated SMAD1/5 levels affects distinct target genes, which are susceptible to low levels of phosphorylated SMADs (such as ID1–3) or dependent on high levels of phosphorylated SMAD1/5 (NOG, noggin). Thus, FSS lowers the threshold for genes dependent on high levels of phosphorylated SMAD1/5 when less BMP is available. While the impact of FSS on direct BMP target genes is independent of YAP/TAZ, FSS acts cooperatively with YAP/TAZ on TGF‐β  target genes, which are shared by both pathways (such as CTGF). As mechanical stimuli are key in bone regeneration, their crosstalk to biochemical signaling pathways such as BMP and TGF‐β and YAP/TAZ acts on different levels, which allows now to think about new and more specified intervention strategies for age‐related bone loss.
Regulation of Electronic Properties of Metal Oxide Nanoparticles to Reveal Their Toxicity Mechanism and Safe‐by‐Design Approach
Authors: Zheng Runxiao , Zhang Haiyuan
Published: January 2021

Metal oxide (MO) nanoparticles (NPs) are widely applied to medicine, agriculture, industry, and other fields, however, their potential toxicity is often concerned. Various toxicological studies are carried out to investigate the toxicity and underlying mechanism of MO NPs. A series of physicochemical properties of MO NPs, such as primary size, charge, solubility, crystal structure, crystalline phase, etc., are correlated with their induced toxicity. Recently, electronic properties of MO NPs have exhibited intense correlation with the oxidative injury in cells and mice. The overlap between the conduction band energy (Ec) of MO NPs and the biological redox potential range (−4.12 to −4.84 eV) of biological systems shows increasing evidence in causing the oxidative injury. Charge carrier types (hole or electron) of MO NPs are further found to potentiate or alleviate these injuries. Based on this knowledge, safer MO NPs can be prepared through regulation of energy edges of MO NPs. Herein, the relationship between the electronic properties of MO NPs and their induced oxidative injury is summarized, and the new safe‐by‐design approach for preparing safer MO NPs is introduced.
A Wearable Optical Microfibrous Biomaterial with Encapsulated Nanosensors Enables Wireless Monitoring of Oxidative Stress
Authors: Safaee Mohammad Moein , Gravely Mitchell , Roxbury Daniel
Published: January 2021

In an effort to facilitate personalized medical approaches, the continuous and noninvasive monitoring of biochemical information using wearable technologies can enable a detailed understanding of an individual's physiology. Reactive oxygen species (ROS) are a class of oxygen‐containing free radicals that function in a wide range of biological processes. In wound healing applications, the continuous monitoring of ROS through a wearable diagnostics platform is essential for the prevention of chronicity and pathogenic infection. Here, a versatile one‐step procedure is utilized to fabricate optical core‐shell microfibrous textiles incorporating single‐walled carbon nanotubes (SWCNTs) for the real‐time optical monitoring of hydrogen peroxide concentrations in in vitro wounds. The environmentally sensitive and non‐photobleachable fluorescence of SWCNTs enables continuous analyte monitoring without decay in signal over time. The existence of multiple chiralities of SWCNTs emitting near‐infrared fluorescence with narrow bandwidths allows a ratiometric signal readout invariant to the excitation source distance and exposure time. The individual fibers encapsulate the SWCNT nanosensors for at least 21 days without apparent loss in structural integrity. Moreover, the microfibrous textiles are utilized to spatially resolve peroxide concentrations using a camera and further integrated into commercial wound bandages without significant degradation in their optical properties.
Strain‐Controlled Spin Wave Excitation and Gilbert Damping in Flexible Co2FeSi Films Activated by Femtosecond Laser Pulse
Authors: Zhang Zhi , Liu Er , Lu Xianyang , Zhang Wen , You Yurong , Xu Guizhou , Xu Zhan , Wong Ping Kwan Johnny , Wang Yichuan , Liu Bo , Yu Xiaojiang , Wu Jing , Xu Yongbing , Wee Andrew Thye Shen , Xu Feng
Published: January 2021

The dynamic response of magnetic order to optical excitation at sub‐picosecond scale has offered an intriguing alternative for magnetism manipulation. Such ultrafast optical manipulation of magnetism has become a fundamental challenging topic with high implications for future spintronics. Here, this study demonstrates such manipulation in Co2FeSi films grown on flexible polyimide substrate, and demonstrates how the magneto‐optical interaction can be modified by using strain engineering which in turn triggers the excitation of both dipolar and exchange spin waves modes. Furthermore, Gilbert damping and spin‐orbit coupling in Co2FeSi can both be tuned significantly by altering the magnitude and type of applied strain, suggesting an appealing way to manipulate spin wave propagation. These results develop the optical manipulation magnetism into the field of spin wave dynamics, and open a new direction in the application of spin orbitronics and magnonics devices using strain engineering.
In Situ Observation of Point‐Defect‐Induced Unit‐Cell‐Wise Energy Storage Pathway in Antiferroelectric PbZrO3
Authors: Wei Xian‐Kui , Jia Chun‐Lin , Roleder Krystian , Dunin‐Borkowski Rafal E. , Mayer Joachim
Published: January 2021

Phase transition is established to govern electrostatic energy storage for antiferroelectric (AFE)‐type dielectric capacitors. However, the source of inducing the phase transition and the pathway of storing the energy remains elusive so far given the ultrafast charging/discharging process under normal working conditions. Here, by slowing down the phase‐transition speed using electron‐beam irradiation as an external stimulus, the in situ dynamic energy‐storage process in AFE PbZrO3 is captured by using atomic‐resolution transmission electron microscopy. Specifically, it is found that oxygen‐lead‐vacancy‐induced defect core acts as a seed to initiate the antiferrodistortive‐to‐ferrodistortive transition in antiparallel‐Pb‐based structural frames. Associated with polarity evolution of the compressively strained defect core, the ferroelectric (FE)–ferrodistortive state expands bilaterally along the b‐axis direction and then develops into charged domain configurations during the energy‐storage process, which is further evidenced by observations at the ordinary FE states. With filling the gap of perception, the findings here provide a straightforward approach of unveiling the unit‐cell‐wise energy storage pathway in chemical defect‐engineered dielectric ceramics.
Ultraflexible and Malleable Fe/BaTiO3 Multiferroic Heterostructures for Functional Devices
Authors: Zhao Yanan , Peng Renci , Guo Yunting , Liu Zhijie , Dong Yongqi , Zhao Shishun , Li Yaojin , Dong Guohua , Hu Yue , Zhang Junwei , Peng Yong , Yang Tiannan , Tian Bian , Zhao Yifan , Zhou Ziyao , Jiang Zhuangde , Luo Zhenlin , Liu Ming
Published: January 2021

The high demand for flexible spintronics based on multiferroic heterostructures makes growing high‐quality flexible, functional oxides urgently, in which needs to be deposited on lattice‐matched substrates. In this paper, ultraflexible and malleable iron (Fe)/BaTiO3 (BTO) multiferroic heterostructures are demonstrated, showing a perfect crystallinity and hetero‐epitaxial growth. In terms of performance, they indicate good multiferroic properties and excellent bending tunability, as well as obvious magnetoelectric (ME) coupling effect. During the phase transformation from the rhombohedral phase to the orthorhombic phase of BTO layers in the heating process, a large ME coupling coefficient of 120 Oe °C−1 along the out‐of‐plane direction is obtained. This value keeps consistent in the phase‐field simulation of magnetic domain evolution, in which the biaxial compressive strain induced‐magnetoelastic anisotropy facilitates the magnetic easy axis of Fe layers to the [110] or [–1–10] direction. Besides, ultraflexible Fe/BTO heterostructures are found to have a 690 Oe ferromagnetic resonance (FMR) field shift along the out‐of‐plane direction under the flexible tuning (R = 5 mm). This work should pave a way toward flexible spintronic and functional devices with fast speed, portability, and low energy consumption.
Defective Graphitic Carbon Nitride Modified Separators with Efficient Polysulfide Traps and Catalytic Sites for Fast and Reliable Sulfur Electrochemistry
Authors: Tong Zhaoming , Huang Liang , Liu Haipeng , Lei Wen , Zhang Haijun , Zhang Shaowei , Jia Quanli
Published: January 2021

The serious shuttle effect of lithium‐sulfur batteries limits the efficient realization of high rate charging and discharging under high sulfur loading in practical applications. Herein, this work reports a strong mitigation toward lithium polysulfide (LiPSs) adsorption/catalysis by introducing defective graphite phase carbon nitride (g‐C3N4) as an effective additive. Without significant weight increase, the nitrogen deficient g‐C3N4, in the form of ultrafine spindle‐like nitrogen deficient g‐C3N4−x (sCN), can be easily combined with commercial poly‐propylene (PP) separators after hydrophilic modification of polydopamine, which corresponds to an ultralow overall weightiness contribution of 0.17 mg cm−2. Physical/electrochemical characterizations and theoretical studies reveal that sCN exhibits strong electrostatic attraction with LiPSs by nitrogen defects and new formation of cyano groups near edges, thereby maintaining rapid and reliable LiS electrochemistry. Of particular importance is the chainmail catalyst design with separators that enable magic polysulfides adsorption effect and desirable thermostability/wettability, which guarantees the sCNPP‐assembled cells with long and stable durability over 500 cycles at 5.0 C (capacity fading rate: 0.05% per cycle), and a high capability of 476 mAh g−1 is obtained.
Effects of Mesenchymal Stem Cell‐Derived Paracrine Signals and Their Delivery Strategies
Authors: Chang Calvin , Yan Jerry , Yao Zhicheng , Zhang Chi , Li Xiaowei , Mao Hai‐Quan
Published: January 2021

Mesenchymal stem cells (MSCs) have been widely studied as a versatile cell source for tissue regeneration and remodeling due to their potent bioactivity, which includes modulation of inflammation response, macrophage polarization toward proregenerative lineage, promotion of angiogenesis, and reduction in fibrosis. This review focuses on profiling the effects of paracrine signals of MSCs, commonly referred to as the secretome, and highlighting the various engineering approaches to tune the MSC secretome. Recent advances in biomaterials‐based therapeutic strategies for delivery of MSCs and MSC‐derived secretome in the form of extracellular vesicles are discussed, along with their advantages and challenges.
3D‐Printable Fluoropolymer Gas Diffusion Layers for CO2 Electroreduction
Authors: Wicks Joshua , Jue Melinda L. , Beck Victor A. , Oakdale James S. , Dudukovic Nikola A. , Clemens Auston L. , Liang Siwei , Ellis Megan E. , Lee Geonhui , Baker Sarah E. , Duoss Eric B. , Sargent Edward H.
Published: January 2021

The electrosynthesis of value‐added multicarbon products from CO2 is a promising strategy to shift chemical production away from fossil fuels. Particularly important is the rational design of gas diffusion electrode (GDE) assemblies to react selectively, at scale, and at high rates. However, the understanding of the gas diffusion layer (GDL) in these assemblies is limited for the CO2 reduction reaction (CO2RR): particularly important, but incompletely understood, is how the GDL modulates product distributions of catalysts operating in high current density regimes > 300 mA cm−2. Here, 3D‐printable fluoropolymer GDLs with tunable microporosity and structure are reported and probe the effects of permeance, microstructural porosity, macrostructure, and surface morphology. Under a given choice of applied electrochemical potential and electrolyte, a 100× increase in the C2H4:CO ratio due to GDL surface morphology design over a homogeneously porous equivalent and a 1.8× increase in the C2H4 partial current density due to a pyramidal macrostructure are observed. These findings offer routes to improve CO2RR GDEs as a platform for 3D catalyst design.
MnO2‐Based Materials for Environmental Applications
Authors: Yang Ruijie , Fan Yingying , Ye Ruquan , Tang Yuxin , Cao Xiehong , Yin Zongyou , Zeng Zhiyuan
Published: January 2021

Manganese dioxide (MnO2) is a promising photo–thermo–electric‐responsive semiconductor material for environmental applications, owing to its various favorable properties. However, the unsatisfactory environmental purification efficiency of this material has limited its further applications. Fortunately, in the last few years, significant efforts have been undertaken for improving the environmental purification efficiency of this material and understanding its underlying mechanism. Here, the aim is to summarize the recent experimental and computational research progress in the modification of MnO2 single species by morphology control, structure construction, facet engineering, and element doping. Moreover, the design and fabrication of MnO2‐based composites via the construction of homojunctions and MnO2/semiconductor/conductor binary/ternary heterojunctions is discussed. Their applications in environmental purification systems, either as an adsorbent material for removing heavy metals, dyes, and microwave (MW) pollution, or as a thermal catalyst, photocatalyst, and electrocatalyst for the degradation of pollutants (water and gas, organic and inorganic) are also highlighted. Finally, the research gaps are summarized and a perspective on the challenges and the direction of future research in nanostructured MnO2‐based materials in the field of environmental applications is presented. Therefore, basic guidance for rational design and fabrication of high‐efficiency MnO2‐based materials for comprehensive environmental applications is provided.
Simultaneous Incorporation of Two Types of Azo‐Groups in the Side Chains of a Conjugated D–A Polymer for Logic Control of the Semiconducting Performance by Light Irradiation
Authors: Tian Jianwu , Liu Zitong , Wu Changchun , Jiang Wenlin , Chen Liangliang , Shi Dandan , Zhang Xisha , Zhang Guanxin , Zhang Deqing
Published: January 2021

A new design strategy for photoresponsive semiconducting polymer with tri‐stable semiconducting states is reported by simultaneous incorporation of tetra‐ortho‐methoxy‐substituted azobenzene (mAzo) and arylazopyrazole (pAzo) in the side chains. The trans‐to‐cis transformations for mAzo and pAzo groups can sequentially occur within the polymer thin film after sequential 560 and 365 nm light irradiation. Remarkably, the trans–cis isomerization of mAzo and pAzo groups can modulate the thin film crystallinity. Accordingly, the performances of the resulting field‐effect transistors (FETs) can be reversibly modulated, leading to tri‐stable semiconducting states after sequential 560, 365, and 470 nm light irradiation. Therefore, the device performance can be logically controlled by light irradiation at three different wavelengths. In addition, with light irradiation and device current as the input and output signals, the three‐value logic gate by using single FET device can be successfully mimicked.
Supramolecular Assembled Programmable Nanomedicine As In Situ Cancer Vaccine for Cancer Immunotherapy
Authors: Zhang Yu , Ma Sheng , Liu Xinming , Xu Yudi , Zhao Jiayu , Si Xinghui , Li Hongxiang , Huang Zichao , Wang Zhenxin , Tang Zhaohui , Song Wantong , Chen Xuesi
Published: January 2021

Using nanotechnology for improving the immunotherapy efficiency represents a major research interest in recent years. However, there are paradoxes and obstacles in using a single nanoparticle to fulfill all the requirements in the complicated immune activation processes. Herein, a supramolecular assembled programmable immune activation nanomedicine (PIAN) for sequentially finishing multiple steps after intravenous injection and eliciting robust antitumor immunity in situ is reported. The programmable nanomedicine is constructed by supramolecular assembly via host–guest interactions between poly‐[(N‐2‐hydroxyethyl)‐aspartamide]‐Pt(IV)/β‐cyclodextrin (PPCD), CpG/polyamidoamine‐thioketal‐adamantane (CpG/PAMAM‐TK‐Ad), and methoxy poly(ethylene glycol)‐thioketal‐adamantane (mPEG‐TK‐Ad). After intravenous injection and accumulation at the tumor site, the high level of reactive oxygen species in the tumor microenvironment promotes PIAN dissociation and the release of PPCD (mediating tumor cell killing and antigen release) and CpG/PAMAM (mediating antigen capturing and transferring to the tumor‐draining lymph nodes). This results in antigen‐presenting cell activation, antigen presentation, and robust antitumor immune responses. In combination with anti‐PD‐L1 antibody, the PIAN cures 40% of mice in a colorectal cancer model. This PIAN provides a new framework for designing programmable nanomedicine as in situ cancer vaccine for cancer immunotherapy.
Solution Processing of Lithium‐Rich Amorphous Li‐La‐Zr‐O Ion Conductor and Its Application for Cycling Durability Improvement of LiCoO2 Cathode as Coating Layer
Authors: Bui Tan Tan , Yun Boseon , Darko Kwabena , Shin Seung Beom , Kim Jaehyun , Hong Jongin , Lee Minah , Park Sung Kyu , Kim Myung‐Gil
Published: January 2021

Lithium‐rich amorphous Li‐La‐Zr‐O (a‐Li‐La‐Zr‐O) electrolyte is successfully synthesized using sol–gel processing method. With unlimited compositions of the amorphous structure, lithium‐rich compositions are systematically investigated to determine optimal composition and optimized processing conditions of a‐Li‐La‐Zr‐O coatings. There is an improvement in ionic conductivity of a‐Li‐La‐Zr‐O with Li content increasing, specifically from 3.0 × 10−8 S cm−1 (Li8La2Zr2O11) to 1.18 × 10−6 S cm−1 (Li18La2Zr2O16), thereby resulting in low activation energy. The high‐ionic‐conductivity a‐Li‐La‐Zr‐O is implemented as an artificial solid electrolyte interface coating layer on cathode materials. The a‐Li‐La‐Zr‐O‐coated LiCoO2 (LCO) and LiNi0.8Mn0.1Co0.1O2 (NMC 811) coin cells exhibit better cycling performance than the bare coin cell at the optimum compositional ratio of a‐Li‐La‐Zr‐O. A‐Li‐La‐Zr‐O can be a promising material for solid electrolyte battery and a potential coating layer for the modification of cathode surface.
Multimodal Spectroscopic Study of Surface Termination Evolution in Cr2TiC2Tx MXene
Authors: Hart James L. , Hantanasirisakul Kanit , Lang Andrew C. , Li Yuanyuan , Mehmood Faisal , Pachter Ruth , Frenkel Anatoly I. , Gogotsi Yury , Taheri Mitra L.
Published: January 2021

Control of surface functionalization of MXenes holds great potential, and in particular, may lead to tuning of magnetic and electronic order in the recently reported magnetic Cr2TiC2Tx. Here, vacuum annealing experiments of Cr2TiC2Tx are reported with in situ electron energy loss spectroscopy and novel in situ Cr K‐edge extended energy loss fine structure analysis, which directly tracks the evolution of the MXene surface coordination environment. These in situ probes are accompanied by benchmarking synchrotron X‐ray absorption fine structure measurements and density functional theory calculations. With the etching method used here, the MXene has an initial termination chemistry of Cr2TiC2O1.3F0.8. Annealing to 600 °C results in the complete loss of F, but O termination is thermally stable up to (at least) 700 °C. These findings demonstrate thermal control of F termination in Cr2TiC2Tx and offer a first step toward termination engineering this MXene for magnetic applications. Moreover, this work demonstrates high energy electron spectroscopy as a powerful approach for surface characterization in 2D materials.
Non‐Local Reconfigurable Sparse Metasurface: Efficient Near‐Field and Far‐Field Wavefront Manipulations
Authors: Popov Vladislav , Ratni Badreddine , Burokur Shah Nawaz , Boust Fabrice
Published: January 2021

In recent years, metasurfaces have shown extremely powerful abilities for manipulation of electromagnetic waves. However, the local electromagnetic response of conventional metasurfaces yields an intrinsic performance limitation in terms of efficiency, minimizing their implementation in real‐life applications. The efficiency of reconfigurable metasurfaces further decreases because of the high density of meta‐atoms, reaching 74 meta‐atoms per λ2 area, incorporating lossy tunable elements. To address these problems, strong electromagnetic non‐local features are implemented in a sparse metasurface composed of electronically reconfigurable meta‐atoms. As a proof‐of‐concept demonstration, a dynamic sparse metasurface having as few as 8 meta‐atoms per λ2 area is experimentally realized in the microwave domain to control 2D wavefronts in both near‐field and far‐field regions for focusing and beam‐forming, respectively. The proposed metasurface with its sparsity not only facilitates design and fabrication, but also opens the door to high‐efficiency real‐time reprogrammable functionalities in beam manipulations, wireless power transfer, and imaging holography.
Recent Advances on Molecular Crystalline Luminescent Materials for Optical Waveguides
Authors: Wu Siqin , Zhou Bo , Yan Dongpeng
Published: January 2021

Molecule‐based fluorescent materials with optical waveguides (MFOWs) have attracted great research interest in the optoelectronic and photonic fields due to their unique photoluminescence properties. Theoretically, the waveband of propagated light within the MFOWs can cover the entire visible light region, which has been one of the important branches in micro/nanophotonics. In this review, the research progress of MFOWs during the last few years, including the basic emission parameters, waveguiding mechanisms, and design methods including adjustments of size, dimension, and shape at the micro/nano‐scales is systematically summarized. New emerging materials (such as flexible nanostructures, molecular cocrystals, and organic–inorganic hybrids) are described towards the high‐performance MFOWs applications. Although tremendous researches for developing MFOWs have been conducted, there remain several dilemmas, such as the deep understanding on elucidated mechanisms and the difficulty for commercialization. Thus, this work also presents the existing challenges and insightful trends, which offer potential guidance for the design and development of MFOWs in future.
Enhanced Energy Transfer from Nitrogen‐Vacancy Centers to Three‐Dimensional Graphene Heterostructures by Laser Nanoshaping
Authors: Liu Jing , Hu Yaowu , Kumar Prashant , Liu Xingtao , Irudayaraj Joseph M. K. , Cheng Gary J.
Published: January 2021

Graphene, a well‐studied 2D material, is used to tailor the emission behavior of proximal light emitters by controlling the energy flow to modulate the related relaxation rates, with potentials in fields of biosensing and photovoltaics. Good interface between emitters and 2D materials are important to efficiently modulate the photon emission behavior. However, seamless integration of quantum light emitters and atomically thin materials is challenging due to fabrication limitation. In this paper, the utilization of laser nanoshaping approaches to “wrap” the atomically thin graphene on nanodiamond particles is reported. Compared with 2D layout, the 3D integration enhances the energy transfer by 45%. Furthermore, it is found that the energy transfer efficiency of nitrogen‐vacancy (NV) centers to the 3D graphene can reach a maximum value of 80% over a long distance (≈25 nm), under intense laser excitation. The authors’ analysis indicates that the photon‐generated carrier density of graphene enhances the nonradiative decay rate of NV centers. Besides contributing new insight on the fundamentals of interactions between graphene and quantum emitters, the effort undertaken furthermore holds tremendous promise in developing the graphene‐based nano‐cavities for various applications ranging from sensing, to photovoltaics, to lasing, and to quantum communications.
Realizing Near‐Infrared Laser Dyes through a Shift in Excited‐State Absorption
Authors: Aoki Reiko , Komatsu Ryutaro , Goushi Kenichi , Mamada Masashi , Ko Soo Young , Wu Jeong Weon , Placide Virginie , D'Aléo Anthony , Adachi Chihaya
Published: January 2021

The development of near‐infrared (NIR) light sources has attracted much interest due to their attractive applications, such as biosensing and light detection and ranging (LiDAR). In particular, organic semiconductor laser diodes with NIR emission are emerging as a next generation technology. However, organic NIR emitters have generally suffered from a low quantum yield, which has resulted in only a few examples of organic solid‐state NIR lasers. In this study, the authors demonstrate a highly efficient NIR emitter based on a boron difluoride curcuminoid structure, which shows a high photoluminescence (PL) quantum yield (ΦPL) at >700 nm and a high fluorescence radiative rate constant in a solid‐state film. Amplified spontaneous emission and lasing occurs at >800 nm with very low thresholds. The large redshift of the stimulated emission is attributed to the transition from the lowest excited state to the different vibrational levels of the ground state owing to the overlap between the emission and the singlet–singlet excited‐state absorption.
Formal [3+2] Cycloaddition Between in situ Formed 1,4‐Benzodiazepin‐2‐One‐Based Azomethine Ylides and Azodicarboxylic Acid Derivatives: Diastereoselective Synthesis of Spiro‐1,4‐Benzodiazepin‐2‐Ones
Authors: Fan Xiao‐Zu , Wu Hui‐Hui , Tang Zhe , Zhang Heng , Cai Lu‐Yu , Bi Xiao‐Fan , Zhao Hong‐Wu
Published: January 2021

In the presence of PhCO2H (20 mol%), the formal [3+2] cycloaddition between in situ formed 1,4‐benzodiazepin‐2‐one‐based azomethine ylides and azodicarboxylic acid derivatives proceeded readily, thus leading to the formation of trans‐configured spiro‐1,4‐benzodiazepin‐2‐ones in up to 98% chemical yield with >20:1 dr. The relative configuration of the title compounds was unambiguously determined by means of X‐ray single crystal structure analysis. The reaction mechanism was hypothesized to account for the diastereoselective formation of the isolated spiro‐1,4‐benzodiazepin‐2‐ones.

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Monolithic‐Integrated Multiplexed Devices Based on Metasurface‐Driven Guided Waves
Authors: Ha Yingli , Guo Yinghui , Pu Mingbo , Li Xiong , Ma Xiaoliang , Zhang Zuojun , Luo Xiangang
Published: January 2021

The appearance of metasurfaces has solved the difficult problems of bulkiness, the complexity of traditional optics, and arbitrary optical response controlling. However, most free‐space metasurfaces and existing integrated metadevices do not meet the criteria of full on‐chip integration toward low loss and high information transmission capacity. Here, by decorating silicon‐on‐insulator waveguides with metasurfaces, one can realize the arbitrary phase and intensity manipulation of guided waves. Four‐channel multiplexer is demonstrated with inherent advantages of low loss and independent transmission of electromagnetic waves in x and y directions. As proof‐of‐concept demonstrations, monolithic‐integrated multiplexed orbital angular momentum (OAM) and holographic generators are developed at 1550 nm to realize high information transmission capacity, low loss, and low crosstalk. Specifically, when the electromagnetic wave is incident from x, −x, y, and −y directions, four kinds of OAM mode with different topological charge values (−1, +1, +2, and −2), and four different holographic images of the letter “U,” “C,” “A,” and “S” can be obtained with the four‐channel multiplexed OAM generator and holographic display device, respectively. The design methods proposed here are expected to open a new perspective for future versatile utilization of driven guided waves to achieve numerous functionalities.
Bilayer Tellurene: A Potential p‐Type Channel Material for Sub‐10 nm Transistors
Authors: Li Qiuhui , Xu Lin , Liu Shiqi , Yang Jie , Fang Shibo , Li Ying , Ma Jiachen , Zhang Zhiyong , Quhe Ruge , Yang Jinbo , Lu Jing
Published: January 2021

The emerging two‐dimensional (2D) tellurium (tellurene) has attracted much attention due to its high carrier transportability and prominent air stability. Micrometer‐scale bilayer (BL) tellurene field‐effect transistors (FETs) are successfully fabricated with a large on/off current ratio of about 105. Here, the transport properties of both the n‐ and p‐type double‐gated sub‐10 nm BL tellurene metal‐oxide‐semiconductor FETs (MOSFETs) are systematically explored by using ab initio quantum transport simulation. The optimized 5, 7, and 9 nm gate‐length p‐type x‐ and y‐directed BL tellurene MOSFETs with a proper underlap and negative capacitance dielectric can meet or nearly meet the on‐state current, delay time, power dissipation, and energy‐delay product requirements of the International Technology Roadmap for Semiconductors for the 2022–2028 horizons for high‐performance applications. This renders BL tellurene to join the air‐stable channel candidate for the p‐type sub‐10 nm transistors.
Water Invoking Interface Corrosion: An Energy Density Booster for Ni//Zn Battery
Authors: He Weidong , Wang Shouzhi , Shao Yongliang , Kong Zhen , Tu Huayao , Wu Yongzhong , Hao Xiaopeng
Published: January 2021

Advanced Ni//Zn batteries possess great promise that combines battery‐level energy density and capacitor‐level power density. However, the surface chemical reactivity of the cathode is generally restricted by active material utilization, leading to an insensitive edge site and unsatisfactory capacity. Herein, a simple and energy‐saving strategy is reported for manipulating the bimetallic sulfide nanointerfaces via water invoking interface corrosion to achieve a 200% increase in the capacity of electrodes. The combined action of water and oxygen causes secondary in situ growth of NiCo–OH nanosheet coating layers on the CoxNi3‐xS2 nanowalls with surface enrichment of low‐valence mixed states, which deliver remarkable reactive activity and structural stability. As a result, the 3D cathode yields an ultrahigh capacity of 2.45 mAh cm−2, higher than that of the pristine nanomaterial (1.20 mAh cm−2). The resulting Ni//Zn battery with excellent reversibility and long‐life, achieves a remarkable energy density of 4.29 mWh cm−2 (728 Wh kg−1), which is superior to most recently reported aqueous Zn‐based batteries and is even comparable to Li‐ion batteries. This work explores the interface corrosion mechanism and corrosion‐surface activity relationship, which is a powerful strategy to construct high surface electrochemical activity of metallic sulfides/phosphides for renewable energy storage devices.
Revealing Morphology Evolution in Highly Efficient Bulk Heterojunction and Pseudo‐Planar Heterojunction Solar Cells by Additives Treatment
Authors: He Qiannan , Sheng Wangping , Zhang Ming , Xu Guodong , Zhu Peipei , Zhang Huotian , Yao Zhaoyang , Gao Feng , Liu Feng , Liao Xunfan , Chen Yiwang
Published: January 2021

Additives treatment is as a very effective strategy to optimize bulk heterojunction (BHJ) morphology. However, the inherent working mechanism of this strategy still lacks systematical investigations in non‐fullerene‐acceptors‐based organic solar cells (OSCs). Herein, a series of BHJ and pseudo‐planar heterojunction (PPHJ) OSCs using PM6 and IT‐4F as the electron donor/acceptor pair, are developed to unveil the promoting effect of solvent additive 1, 8‐diiodooctane (DIO) on active layer morphologies and device performance. The study clearly demonstrates that DIO can increase the crystallinity of IT‐4F significantly, while it has less impact on PM6. It is notable that a new efficiency‐determining crystalline balanced factor (CCLpolymer/CCLacceptor) is put forward, indicating that the more balanced CCLpolymer/CCLacceptor results in more balanced charge mobility and much better short‐circuit current densities (Jsc) and fill factors (FF) of OSCs. The PPHJ blend film of PM6/IT‐4F(DIO) exhibits enhanced crystallinity with more balanced CCL and favorable hierarchical distribution morphology, contributing to a champion efficiency of 13.70% with a record Jsc of 20.98 mA cm−2 and a remarkable FF of 75.9%. This work not only reveals the underlying mechanism of DIO caused morphology evolution, but also achieves highly efficient PPHJ OSCs with superior thermal stability by elaborately controlling the morphology of PPHJ film.
Insights from Transient Absorption Spectroscopy into Electron Dynamics Along the Ga‐Gradient in Cu(In,Ga)Se2 Solar Cells
Authors: Chang Yu‐Han , Carron Romain , Ochoa Mario , Bozal‐Ginesta Carlota , Tiwari Ayodhya N. , Durrant James R. , Steier Ludmilla
Published: January 2021

Cu(In,Ga)Se2 solar cells have markedly increased their efficiency over the last decades currently reaching a record power conversion efficiency of 23.3%. Key aspects to this efficiency progress are the engineered bandgap gradient profile across the absorber depth, along with controlled incorporation of alkali atoms via post‐deposition treatments. Whereas the impact of these treatments on the carrier lifetime has been extensively studied in ungraded Cu(In,Ga)Se2 films, the role of the Ga‐gradient on carrier mobility has been less explored. Here, transient absorption spectroscopy (TAS) is utilized to investigate the impact of the Ga‐gradient profile on charge carrier dynamics. Minority carriers excited in large Cu(In,Ga)Se2 grains with a [Ga]/([Ga]+[In]) ratio between 0.2–0.5 are found to drift‐diffuse across ≈1/3 of the absorber layer to the engineered bandgap minimum within 2 ns, which corresponds to a mobility range of 8.7–58.9 cm2 V−1 s−1. In addition, the recombination times strongly depend on the Ga‐content, ranging from 19.1 ns in the energy minimum to 85 ps in the high Ga‐content region near the Mo‐back contact. An analytical model, as well as drift‐diffusion numerical simulations, fully decouple carrier transport and recombination behaviour in this complex composition‐graded absorber structure, demonstrating the potential of TAS.
A History and Perspective of Non‐Fullerene Electron Acceptors for Organic Solar Cells
Authors: Armin Ardalan , Li Wei , Sandberg Oskar J. , Xiao Zuo , Ding Liming , Nelson Jenny , Neher Dieter , Vandewal Koen , Shoaee Safa , Wang Tao , Ade Harald , Heumüller Thomas , Brabec Christoph , Meredith Paul
Published: January 2021

Organic solar cells are composed of electron donating and accepting organic semiconductors. Whilst a significant palette of donors has been developed over three decades, until recently only a small number of acceptors have proven capable of delivering high power conversion efficiencies. In particular the fullerenes have dominated the landscape. In this perspective, the emergence of a family of materials–the non‐fullerene acceptors (NFAs) is described. These have delivered a discontinuous advance in cell efficiencies, with the significant milestone of 20% now in sight. Intensive international efforts in synthetic chemistry have established clear design rules for molecular engineering enabling an ever‐expanding number of high efficiency candidates. However, these materials challenge the accepted wisdom of how organic solar cells work and force new thinking in areas such as morphology, charge generation and recombination. This perspective provides a historical context for the development of NFAs, and also addresses current thinking in these areas plus considers important manufacturability criteria. There is no doubt that the NFAs have propelled organic solar cell technology to the efficiencies necessary for a viable commercial technology–but how far can they be pushed, and will they also deliver on equally important metrics such as stability?
Electrochemo‐Mechanical Effects on Structural Integrity of Ni‐Rich Cathodes with Different Microstructures in All Solid‐State Batteries
Authors: Liu Xiangsi , Zheng Bizhu , Zhao Jun , Zhao Weimin , Liang Ziteng , Su Yu , Xie Chenpeng , Zhou Ke , Xiang Yuxuan , Zhu Jianping , Wang Hongchun , Zhong Guiming , Gong Zhengliang , Huang Jianyu , Yang Yong
Published: January 2021

The electrochemo‐mechanical effects on the structural integrity of electrode materials during cycling is a non‐negligible factor that affects the cyclability and rate performance of all solid‐state batteries (ASSBs). Herein, combined with in situ electrochemical impedance spectroscopy (EIS), focused ion beam (FIB)–scanning electron microscope (SEM), and solid state nuclear magnetic resonance (ssNMR) techniques, the electrochemical performance and electrochemo‐mechanical behavior are compared of conventional polycrystalline NCM811 (LiNi0.8Co0.1Mn0.1O2), small‐size polycrystalline NCM811 and single‐crystal (S‐) NCM811 in Li10SnP2S12 based ASSBs during long charge–discharge cycles. The results show that the deteriorating performance of both large and small polycrystalline NCM811 originates from their inherent structural instability at >4.15 V, induced by the visible voids between the randomly oriented grains and microcracks due to the electrode pressing process and severe anisotropic volume change during cycling, rather than lithium ion transport in the primary particle. In contrast, S‐NCM811 with good microstructural integrity show remarkably high capacity (187 mAh g−1, 18 mA g−1), stable cyclability (100 cycles, retention of 64.5%), and exceptional rate capability (102 mAh g−1 at 180 mA g−1) in ASSBs even without surface modification. Moreover, 1 wt% LiNbO3@S‐NCM811 further demonstrates excellent initial discharge capacity and capacity retention. This work highlights the critical role of electrochemo‐mechanical integrity and offers an promising path towards mechanically‐reliable cathode materials for ASSBs.
Epitaxial Induced Plating Current‐Collector Lasting Lifespan of Anode‐Free Lithium Metal Battery
Authors: Lin Liangdong , Suo Liumin , Hu Yong‐sheng , Li Hong , Huang Xuejie , Chen Liquan
Published: January 2021

Anode‐free designs can obtain the ultimate energy density of lithium metal batteries. However, without a continuous Li supply from the anode side, it is much more challenging to achieve high capacity retention with a competitive energy density. Here, the lifespan of an anode‐free Li metal battery is prolonged by applying an epitaxial induced plating current‐collector (E‐Cu). The functional layer on E‐Cu initiates Li storage by an alloying approach, forming an epitaxial induce layer, which exhibits speedy surface diffusion for of Li‐ions, resulting in the block like epitaxial growth of Li. Moreover, this alloying process also promotes the formation of a LiF‐rich solid electrolyte interphase (SEI), which is very useful for uniform Li plating. Due to the benefits of epitaxial Li plating and LiF‐rich SEI, the initial coulombic efficiency of the E‐Cu/Li asymmetric cell increases from 93.24 to 98.24%, and the capacity retention of anode‐free NCM811/E‐Cu pouch cell increases from 66 to 84% with a remarkable energy density of 420 Wh kg−1 in the condition of limited electrolyte addition (E/C ratio of 2 g Ah−1). This strategy is promising in the development of high energy batteries in extending their lifespans.