bluuebunny/crossref_metadata_2025_split huggingface dataset:
3D Spheroids Versus 3D Tumor‐Like Microcapsules: Confinement and Mechanical Stress May Lead to the Expression of Malignant Responses in Cancer Cells
Authors: Fuentes‐Chandía Miguel , Vierling Andreas , Kappelmann‐Fenzl Melanie , Monavari Mahshid , Letort Gaelle , Höne Lucas , Parma Beatrice , Antara Sharmin Khan , Ertekin Özlem , Palmisano Ralph , Dong Meng , Böpple Kathrin , Boccaccini Aldo R. , Ceppi Paolo , Bosserhoff Anja K. , Leal‐Egaña Aldo 
Published: May 2021

AbstractAs 2D surfaces fail to resemble the tumoral milieu, current discussions are focused on which 3D cell culture strategy may better lead the cells to express in vitro most of the malignant hints described in vivo. In this study, this question is assessed by analyzing the full genetic profile of MCF7 cells cultured either as 3D spheroids‐considered as “gold standard” for in vitro cancer research‐ or immobilized in 3D tumor‐like microcapsules, by RNA‐Seq and transcriptomic methods, allowing to discriminate at big‐data scale, which in vitro strategy can better resemble most of the malignant features described in neoplastic diseases. The results clearly show that mechanical stress, rather than 3D morphology only, stimulates most of the biological processes involved in cancer pathogenicity, such as cytoskeletal organization, migration, and stemness. Furthermore, cells entrapped in hydrogel‐based scaffolds are likely expressing other physiological hints described in malignancy, such as the upregulated expression of metalloproteinases or the resistance to anticancer drugs, among others. According to the knowledge, this study represents the first attempt to answer which 3D experimental system can better mimic the neoplastic architecture in vitro, emphasizing the relevance of confinement in cancer pathogenicity, which can be easily achieved by using hydrogel‐based matrices.
Modulation of Mammalian Cell Behavior by Nanoporous Glass
Authors: Emmert Martin , Somorowsky Ferdinand , Ebert Jutta , Görick Dominik , Heyn Andreas , Rosenberger Eva , Wahl Moritz , Heinrich Doris 
Published: May 2021

AbstractThe introduction of novel bioactive materials to manipulate living cell behavior is a crucial topic for biomedical research and tissue engineering. Biomaterials or surface patterns that boost specific cell functions can enable innovative new products in cell culture and diagnostics. This study investigates the influence of the intrinsically nano‐patterned surface of nanoporous glass membranes on the behavior of mammalian cells. Three different cell lines and primary human mesenchymal stem cells (hMSCs) proliferate readily on nanoporous glass membranes with mean pore sizes between 10 and 124 nm. In both proliferation and mRNA expression experiments, L929 fibroblasts show a distinct trend toward mean pore sizes >80 nm. For primary hMSCs, excellent proliferation is observed on all nanoporous surfaces. hMSCs on samples with 17 nm pore size display increased expression of COL10, COL2A1, and SOX9, especially during the first two weeks of culture. In the upside down culture, SK‐MEL‐28 cells on nanoporous glass resist the gravitational force and proliferate well in contrast to cells on flat references. The effect of paclitaxel treatment of MDA‐MB‐321 breast cancer cells is already visible after 48 h on nanoporous membranes and strongly pronounced in comparison to reference samples, underlining the material's potential for functional drug screening.
Surface Segregation and Self‐Assembly of Block‐Copolymer Separation Layers on Top of Homopolymer Substructures in Asymmetric Ultrafiltration Membranes from a Single Casting Step
Authors: Hibi Yusuke , Wiesner Ulrich 
Published: May 2021

AbstractSurface segregation in blended polymer films has attracted much interest in fundamental research as well as for practical applications. A variety of methodologies have been proposed for controlling surface segregation. They often require long annealing times, however, to achieve thermodynamic equilibrium. Here, a strategy and proof‐of‐principle experiments are described to control surface segregation of thin block‐copolymer (BCP) layers on top of a homopolymer in a single casting step from blended BCP/homopolymer solutions. The surface coverage by the minor constituent BCP (2–10 wt%) is accomplished despite almost identical surface energies of BCP and homopolymer constituents. Immersing this casted solution into water for nonsolvent induced phase separation (NIPS), a nonequilibrium process, affords solidified bilayer ultrafiltration membranes composed of a thin porous surface layer of self‐assembled BCP atop an asymmetric porous homopolymer substructure. Key to successful BCP surface segregation is the choice of a binary solvent system based on careful considerations of solvent surface energies and polymer‐solvent interaction parameters. Furthermore, stabilizing the BCP micellar structure by a divalent metal additive is also essential. The approach provides a cost‐effective method for fabricating bilayer‐type asymmetric ultrafiltration membranes with uniform BCP self‐assembly based selective top surface pore layers in a single casting step.
All‐in‐One Hollow Flower‐Like Covalent Organic Frameworks for Flexible Transparent Devices
Authors: Wang Weikang , Zhao Weiwei , Chen Tiantian , Bai Yan , Xu Haotian , Jiang Mengyue , Liu Shujuan , Huang Wei , Zhao Qiang 
Published: May 2021

AbstractCovalent organic frameworks (COFs) exhibit great potential in the application of functional electronic devices. However, there has been no report of the precise fabrication of 3D all‐in‐one hollow micro/nanostructures based on COFs. Here, for the first time, all‐in‐one hollow dioxin‐based COF‐316 microflowers are synthesized measuring 5–7 µm and with interconnected hollow petals through a self‐template strategy. The growth mechanism involves the collaborative process of self‐assembly of nanoparticles, inside‐out Ostwald ripening, and epitaxial growth. Due to the intrinsic porosity and interconnected hollow structure, COF‐316 can uniformly composite with polypyrrole (PPy) through the “interior” and “exterior” functionalization, in which the hydrogen bond interaction enhances the charge transfer efficiency and structural stability in the charge/discharge process. The COF‐316@PPy flexible transparent supercapacitors exhibit an areal specific capacitance (CA) of 783.6 µF cm–2 at 3 µA cm–2 and long‐term cycling stability. This work will boost research on the valuable design concepts of 3D hollow COF materials for energy storage devices.
Combining Photothermal‐Photodynamic Therapy Mediated by Nanomaterials with Immune Checkpoint Blockade for Metastatic Cancer Treatment and Creation of Immune Memory
Authors: Lima‐Sousa Rita , Melo Bruna L. , Alves Cátia G. , Moreira André F. , Mendonça António G. , Correia Ilídio J. , de Melo‐Diogo Duarte 
Published: May 2021

AbstractThe pursuit of effective treatments for metastatic cancer is still one of the most intensive areas of research in the biomedical field. In a not‐so‐distant past, the scientific community has witnessed the rise of immunotherapy based on immune checkpoint inhibitors (ICIs). This therapeutic modality intends to abolish immunosuppressive interactions, re‐establishing T cell responses against metastasized cancer cells. Despite the initial enthusiasm, the ICIs were later found to be associated with low clinical therapeutic outcomes and immune‐related side effects. To address these limitations, researchers are exploring the combination of ICIs with nanomaterial‐mediated phototherapies. These nanomaterials can accumulate within the tumor and produce, upon interaction with light, a temperature increase (photothermal therapy) and/or reactive oxygen species (photodynamic therapy), causing damage to cancer cells. Importantly, these photothermal‐photodynamic effects can pave the way for an enhanced ICI‐based immunotherapy by inducing the release of tumor‐associated antigens and danger‐associated molecular patterns, as well as by relieving tumor hypoxia and triggering a pro‐inflammatory response. This progress report analyses the potential of nanomaterial‐mediated photothermal‐photodynamic therapy in combination with ICIs, focusing on their ability to modulate T cell populations leading to an anti‐metastatic abscopal effect and on their capacity to generate immune memory that prevents tumor recurrence.
Carbonized Wood Decorated with Cobalt‐Nickel Binary Nanoparticles as a Low‐Cost and Efficient Electrode for Water Splitting
Authors: Gan Wentao , Wu Lianping , Wang Yaoxing , Gao He , Gao Likun , Xiao Shaoliang , Liu Jiuqing , Xie Yanjun , Li Teng , Li Jian 
Published: May 2021

AbstractUsing an inexpensive and eco‐friendly wood substrate, herein, a one‐step calcination method is developed to deposit Co‐Ni binary nanoparticles into aligned wood channels and an effective carbonized wood (CW) electrode (termed as Co/Ni‐CW) is fabricated. Well distributed Co‐Ni nanoparticles are achieved by the coordination bonds between the hydroxyl groups on wood matrix and soaked metal cations. Subsequently, high‐temperature calcination promotes the nucleation of Co‐Ni nanoparticles and the formation of CW. With the uniform distribution of Co‐Ni nanoparticles and porous wood structure, not only is a high active surface area, but also the electron and mass diffusion pathways are enhanced. Thus, the as‐prepared Co/Ni‐CW affords the current density of 10 mA cm–2 at low overpotentials of 330 and 157 mV for oxygen and hydrogen evolution, respectively. Remarkably, when the wood‐based bifunctional electrocatalyst is used as both the anode and cathode, a low cell voltage of 1.64 V is required to reach the current density of 10 mA cm–2. Compared with most substrates used in bifunctional electrocatalysts, the abundance, low cost, eco‐friendliness, and easy operation of wood‐based catalysts allow for an active and scalable electrode for water splitting and many other energy storage devices.
Enlarging the Reservoir: High Absorption Coefficient Dyes Enable Synergetic Near Infrared‐II Fluorescence Imaging and Near Infrared‐I Photothermal Therapy
Authors: Li Yuanyuan , Zhang Jianquan , Liu Shunjie , Zhang Chen , Chuah Clarence , Tang Youhong , Kwok Ryan T. K. , Lam Jacky W. Y. , Ou Hanlin , Ding Dan , Tang Ben Zhong 
Published: May 2021

AbstractAlthough organic materials with near infrared (NIR)‐II fluorescence and a photothermal effect have been widely investigated for the accurate diagnosis and treatment of tumors, optimizing the output signals of both remain challenging. Here, a strategy by “enlarging absorption reservoir” to address this issue, since an increase in photon absorption can naturally enhance output signals, is proposed. As a proof‐of‐concept, a large π‐conjugated diketopyrrolopyrrole (DPP) unit is selected to fabricate strong light‐absorbing systems. To enhance solid‐state fluorescence, highly twisted alkylthiophene–benzobisthiadiazole–alkylthiophene and triphenylamine rotor are introduced to restrict the strong intermolecular π–π interactions. Moreover, the number of DPP units in molecules is engineered to optimize photophysical properties. Results show that TDADT with two DPP units possesses an exceptionally high molar absorptivity of 2.1 × 105 L mol−1 cm−1 at 808 nm, an acceptable NIR‐II quantum yield of 0.1% (emission peak at 1270 nm), and a sizeable photothermal conversion efficiency of 60.4%. The excellent photophysical properties of the TDADT nanoparticles are particularly suitable for in vivo NIR‐II imaging‐guided cancer surgery and NIR‐I photothermal therapy. The presented strategy provides a new approach of designing highly efficient NIR‐II phototheranostic agents.
Metal‐Bridged Graphene–Protein Supraparticles for Analog and Digital Nitric Oxide Sensing
Authors: Qu Zhi‐Bei , Zhou Xinguang , Zhang Min , Shen Jianlei , Li Qian , Xu Feng , Kotov Nicholas , Fan Chunhai 
Published: May 2021

AbstractSelf‐limited nanoassemblies, such as supraparticles (SPs), can be made from virtually any nanoscale components, but SPs from nanocarbons including graphene quantum dots (GQDs), are hardly known because of the weak van der Waals attraction between them. Here it is shown that highly uniform SPs from GQDs can be successfully assembled when the components are bridged by Tb3+ ions supplementing van der Waals interactions. Furthermore, they can be coassembled with superoxide dismutase, which also has weak attraction to GQDs. Tight structural integration of multilevel components into SPs enables efficient transfer of excitonic energy from GQDs and protein to Tb3+. This mechanism is activated when Cu2+ is reduced to Cu1+ by nitric oxide (NO)—an important biomarker for viral pulmonary infections and Alzheimer's disease. Due to multipronged fluorescence enhancement, the limit of NO detection improves 200 times reaching 10 × 10–12 m. Furthermore, the uniform size of SPs enables digitization of the NO detection using the single particle detection format resulting in confident registration of as few as 600 molecules mL−1. The practicality of the SP‐based assay is demonstrated by the successful monitoring of NO in human breath. The biocompatible SPs combining proteins, carbonaceous nanostructures, and ionic components provide a general path for engineering uniquely sensitive assays for noninvasive tracking of infections and other diseases.
A Floating Mold Technique for the Programmed Assembly of Protocells into Protocellular Materials Capable of Non‐Equilibrium Biochemical Sensing
Authors: Galanti Agostino , Moreno‐Tortolero Rafael O. , Azad Raihan , Cross Stephen , Davis Sean , Gobbo Pierangelo 
Published: May 2021

AbstractDespite important breakthroughs in bottom‐up synthetic biology, a major challenge still remains the construction of free‐standing, macroscopic, and robust materials from protocell building blocks that are stable in water and capable of emergent behaviors. Herein, a new floating mold technique for the fabrication of millimeter‐ to centimeter‐sized protocellular materials (PCMs) of any shape that overcomes most of the current challenges in prototissue engineering is reported. Significantly, this technique also allows for the generation of 2D periodic arrays of PCMs that display an emergent non‐equilibrium spatiotemporal sensing behavior. These arrays are capable of collectively translating the information provided by the external environment and are encoded in the form of propagating reaction–diffusion fronts into a readable dynamic signal output. Overall, the methodology opens up a route to the fabrication of macroscopic and robust tissue‐like materials with emergent behaviors, providing a new paradigm of bottom‐up synthetic biology and biomimetic materials science.
Surfactant‐Free, One‐Step Synthesis of Lead‐Free Perovskite Hollow Nanospheres for Trace CO Detection
Authors: Ye Wen , He Jing‐Hui , Cao Qiang , Sun Wu‐Ji , Wang Jia , Chen Ze‐Kun , Cheng Xue‐Feng , Yu Chuang , Lu Jian‐Mei 
Published: May 2021

AbstractOwing to their special photoelectric properties, halide perovskites have always attracted research attention. Hollow‐structured halide perovskites have many practical applications but are challenging to prepare as most template methods violate their poor chemical and thermal stability. In this study, novel halide perovskite Cs2PdBr6 hollow nanospheres are prepared using a template‐free method; specifically, large quantities of highly pure lead‐free halide perovskite Cs2PdBr6 hollow nanospheres are produced at 30 °C without a surfactant. These ultrapure nanospheres exhibit superiority in chemresistive detection of CO with a detection limit of 50 ppb, which is the lowest among all the reported CO sensing materials. Moreover, in situ sum‐frequency‐generation spectra and density functional theory calculations reveal that the high sensitivity is attributable to the large specific surface area and surfactant‐free surface of rich Br− vacancies that favor CO binding. Overall, this work provides insight on regulation of the halide perovskite structure and the use of hollow spheres in gas‐sensing applications.
Mixed‐Anion Compounds: An Unexplored Playground for ALD Fabrication
Authors: Tripathi Tripurari Sharan , Karppinen Maarit 
Published: May 2021

AbstractFor decades the most successful approach towards new inorganic material innovations for next‐generation devices has been to manipulate the cation composition. As this cation‐centric material development is inevitably approaching its saturation, new chemistries are needed to maintain the pace of technological progress. One of the new chemistry approaches is to play with the anions instead of the cations. Moreover, advances in fabrication techniques are needed to address the endeavors to shrink the device and component dimensions. Here, the combination of mixed‐anion chemistries, such as oxychalcogenides or carbopnictides, and the state‐of‐the‐art atomic layer deposition (ALD) thin‐film technology are highlighted. The unique bottom‐up material building mode of ALD can lead to scientifically exciting but at the same time industry‐feasible material innovations. In this brief review, the present status and prospects, and the challenges of this emerging field are discussed.
Improved Performances of CVD‐Grown MoS2 Based Phototransistors Enabled by Encapsulation
Authors: Yang Yujue , Liu Zihao , Shu Kaixiang , Li Ling , Li Jingbo 
Published: May 2021

AbstractMoS2 as a semiconducting 2D material has been a promising candidate for the next generation of optoelectronics due to its atomic thickness, mechanical flexibility, complementary metal‐oxide‐semiconductor compatibility, and large‐scale manufacturing. However, the poor quality such as low mobility and numerous defects has much affected the corresponding device performances, which has limited their wide applications. Here, an effective strategy is proposed to significantly improve the quality of the chemical vapor deposition (CVD)‐grown monolayer MoS2 by the encapsulation technique with atomic layer deposition Al2O3. Benefiting from the passivation of defects and suppression of charge Coulomb scattering, the mobility can be improved by more than one order of magnitude, reaching up to 62.5 cm2 Vs−1. As a result, the photodetection performances in terms of response time, responsivity, and detectivity are also improved up to 20 ms, 1.1 × 104 A W−1, and 3.1 × 1012 Jones, respectively. The developed encapsulation technique here for the improvement of film quality and device performance can further enable the practical application of large‐scale 2D materials‐based electronics and photodetectors.
Enhanced Electromechanical Response and Thermal Stability of 0.93(Na1/2Bi1/2)TiO3‐0.07BaTiO3 Through Aerosol Deposition of Base Metal Electrodes
Authors: Khansur Neamul H. , Eckstein Udo , Ursic Hana , Sadl Matej , Brehl Martin , Martin Alexander , Riess Kevin , de Ligny Dominique , Webber Kyle G. 
Published: May 2021

AbstractNa1/2Bi1/2TiO3‐based relaxor ferroelectrics are extensively investigated for use in transduction applications because of their relatively large electromechanical properties. Integration of these materials into devices, however, requires better temperature stability in addition to electromechanical properties. This work demonstrates a novel approach to enhance the temperature stability of the long‐range ferroelectric order as well as to enhance electromechanical properties in a non‐ergodic relaxor 0.93(Na1/2Bi1/2)TiO3‐0.07BaTiO3 (NBT‐7BT) without changing the chemical composition through, for example, chemical substitutions or second phase particles. The approach involves the room temperature deposition of copper electrodes directly on the relaxor ceramic substrate using the aerosol deposition (AD) method. The collision of solid‐state particles with the substrate surface during AD results in large impact and residual stresses, inherent to the AD process, which are shown with piezo‐response force microscopy to induce long‐range ferroelectric domain ordering in non‐ergodic relaxor NBT‐7BT. Using Raman spectroscopy, the magnitude and depth profile of the stress‐induced transformation are determined. It is demonstrated that deposition‐induced stresses significantly increase the temperature stability of the electromechanical properties, where long‐range ferroelectric ordering is observed up to 150 °C, which is approximately 41 °C higher than NBT‐7BT samples without the AD processed electrode. Moreover, the AD treatment also facilitates ferroelectric domain switching at a lower electric field, enabling maximum polarization at a relatively lower field and an enhancement in the piezoelectric response. It is shown that the deposition‐induced stress is responsible for such an enhancement. Importantly, this impact‐stress‐driven tailoring of electromechanical properties can potentially be utilized for other functional ceramic materials as well, where internal residual stress can result in enhanced functional properties.
Design Artificial Stem Cell Nests for Stem Cell Niche in a Microfluidic Petri Dish Programmed by a Cell Phone
Authors: Peng Xing Yue (Larry) , Guo Yaxin , Peng Linghan , Liu Juan 
Published: May 2021

AbstractThis article describes a technology to transform a petri dish into a microfluidic chip with a stem cell nest for stem cell niche engineering. A permanent magnet sphere is put in a 30 mm petri dish as an oscillator pump (O‐pump). An earphone‐sized actuator outside the petri dish receives the programmed audio signal from an MP3 player or a mobile phone to drive the in‐dish O‐pump for a microflow. There are guiding walls to form a wake area for the cell nest at the dish's center. The cell nest uses the wake to create a stable, ultraslow internal microcirculation flow. The retention half‐life of nanoparticles in the cell nest is 1419.8 ± 1.3 s. By setting the microfluidic program and supplementing five drops of the culture medium outside the cell nest every 2 d, the growth rate of embryonic stem cells in the cell nest during the 8 d automatic culture appears significantly optimized. The single clone area of embryonic stem cells increases from (3.57 ± 0.52) × 105 to (11.67 ± 1.33) × 105 µm2 after 2 d of the automatic culture and advances to (53.34 ± 8.37) × 105 µm2 after 4 d.
High‐Performance Hybrid White OLEDs with Ultra‐Stable Emission Color and Small Efficiency Roll‐Off Achieved by Incorporating a Deep‐Blue Fluorescent Neat Film
Authors: Wu Zilong , Zhu Xiangyu , Li Yinghao , Chen Hao , Zhuang Zeyan , Shen Pingchuan , Zeng Jiajie , Chi Jiajin , Ma Dongge , Zhao Zujin , Tang Ben Zhong 
Published: May 2021

AbstractOrganic blue luminescent materials play a vital role in the fabrication of full‐color displays and white lighting devices, but high‐efficiency blue emitters that meet commercial demands are still quite insufficient. Herein, the authors wish to report the design and synthesis of four bipolar deep‐blue luminogens consisting of an anthracene core and various functional groups. Their photophysical properties, electronic structures, electrochemical behavior, thermal stability, carrier transport ability, and electroluminescence performance are systematically studied. The nondoped organic light‐emitting diode (OLED) based on DPAC‐TAn‐BI radiates stable deep‐blue light [Commission Internationale de l'Eclairage (CIEx,y) = 0.15, 0.15] with a high external quantum efficiency (ηext) of 5.81%. Moreover, efficient two‐color hybrid warm white OLEDs are achieved using DPAC‐TAn‐BI neat film as a blue‐emitting layer, providing an excellent ηext of 27.6%, a small efficiency roll‐off of 2.9% at 1000 cd m−2, and ultra‐stable emission spectra with tiny CIEx,y variation of (0.01, 0.01) from 100 to 10 000 cd m−2. These results demonstrate that the deep‐blue luminogens are strong candidates for applications in blue and white OLEDs.