bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hydrogen‐Bonding Triggered Assembly to Configure Hollow Carbon Nanosheets for Highly Efficient Tri‐Iodide Reduction
Authors: Chang Jiangwei , Song Xuedan , Yu Chang , Yu Jinhe , Ding Yiwang , Yao Chun , Zhao Zongbin , Qiu Jieshan 
Published: September 2020

AbstractCarbon materials have rapidly grown as highly promising candidates to replace noble metal catalysts in energy storage/conversion technologies. In this work, a strategy of hydrogen‐bonding triggered assembly to configure hollow carbon nanosheets by applying Silicalite‐1 as a substrate in the aqueous solution of dopamine is reported. Remarkably, the combined density functional theory modelling and experimental verification present a molecule/nano‐scale insight into the nature of the bonding behavior during the fabrication process. It is demonstrated that the SiOH on the surface of Silicalite‐1 acts as an anchor and that it is energetically favorable to pre‐adsorb the building blocks of polydopamine by hydrogen‐bonding, which triggers the subsequent assembly. As an example, the as‐prepared hollow carbon nanosheets with unique structure can efficiently catalyze tri‐iodide reduction and a power conversion efficiency up to 8.58%.
Truly Electroforming‐Free Memristor Based on TiO2‐CoO Phase‐Separated Oxides with Extremely High Uniformity and Low Power Consumption
Authors: Wan Fuxing , Wang Qianwen , Harumoto Takashi , Gao Tenghua , Ando Kazuya , Nakamura Yoshio , Shi Ji 
Published: September 2020

AbstractOxide‐based memristor devices are being extensively studied as one of the most promising technologies for next generation nonvolatile memory and neuromorphic computing. However, the switching process of such devices relying on the formation and rupture of conductive filaments has not been easily controlled, and thus induces large cycle‐to‐cycle and device‐to‐device variations in resistive switching, which hinders the development of high‐performance memristors. High‐performance memristors that meet the requirements for truly electroforming‐free, highly uniform, and low‐power switching are yet to be developed. Here, a phase‐separated oxide memristor is demonstrated based on a spontaneous phase separation process to form amorphous TiO2 switching medium distributed among the crystalline CoO grains. The confinement of conductive filaments into the intergrain amorphous oxide phase effectively minimizes the stochasticity of filament formation and rupture, resulting in drastically enhanced switching uniformity. The designed microstructure also facilitates filament formation and dissolution during switching processes and leads to truly electroforming‐free switching and low switching power (simultaneous low switching voltage 0.4 V and low current 2.5 µA).
Implantable Nanosensors for Human Steroid Hormone Sensing In Vivo Using a Self‐Templating Corona Phase Molecular Recognition
Authors: Lee Michael A. , Wang Song , Jin Xiaojia , Bakh Naveed Ali , Nguyen Freddy T. , Dong Juyao , Silmore Kevin S. , Gong Xun , Pham Crystal , Jones Kelvin K. , Muthupalani Sureshkumar , Bisker Gili , Son Manki , Strano Michael S. 
Published: September 2020

AbstractDynamic measurements of steroid hormones in vivo are critical, but steroid sensing is currently limited by the availability of specific molecular recognition elements due to the chemical similarity of these hormones. In this work, a new, self‐templating synthetic approach is applied using corona phase molecular recognition (CoPhMoRe) targeting the steroid family of molecules to produce near infrared fluorescent, implantable sensors. A key limitation of CoPhMoRe has been its reliance on library generation for sensor screening. This problem is addressed with a self‐templating strategy of polymer design, using the examples of progesterone and cortisol sensing based on a styrene and acrylic acid copolymer library augmented with an acrylated steroid. The pendant steroid attached to the corona backbone is shown to self‐template the phase, providing a unique CoPhMoRE design strategy with high efficacy. The resulting sensors exhibit excellent stability and reversibility upon repeated analyte cycling. It is shown that molecular recognition using such constructs is viable even in vivo after sensor implantation into a murine model by employing a poly (ethylene glycol) diacrylate (PEGDA) hydrogel and porous cellulose interface to limit nonspecific absorption. The results demonstrate that CoPhMoRe templating is sufficiently robust to enable a new class of continuous, in vivo biosensors.
Highly Stretchable Metal–Polymer Conductor Electrode Array for Electrophysiology
Authors: Dong Ruihua , Liu Xiaoyan , Cheng Shiyu , Tang Lixue , Chen Mian , Zhong Leni , Chen Zhen , Liu Shaoqin , Jiang Xingyu 
Published: September 2020

AbstractNarrowing the mechanical mismatch between biological tissues (typically soft) and neural interfaces (hard) is essential for maintaining signal quality for the electrical recording of neural activity. However, only a few materials can satisfy all requirements for such electronics, which need to be both biocompatible and sufficiently soft. Here, a highly stretchable electrode array (SEA) is introduced, based on the liquid metal–polymer conductor (MPC), achieving high mechanical flexibility and good cytocompatability for neural interfaces. By utilizing the MPC, the SEA exhibits high stretchability (≈100%) and excellent cycling stability (>400 cycles). The cytocompatability of the SEA can allow for long‐term culturing of primary neurons and enable signal recording of primary hippocampal neurons. In the future, the SEA could serve as a reliable and robust platform for diagnostics in neuronal tissues and greatly advance brain–machine interfaces.
Attachment of Ultralow Amount of Engineered Plant Viral Nanoparticles to Mesenchymal Stem Cells Enhances Osteogenesis and Mineralization
Authors: Lin Ying‐Ying , Schuphan Juliane , Dickmeis Christina , Buhl Eva Miriam , Commandeur Ulrich , Fischer Horst 
Published: September 2020

AbstractHydrogel‐based materials are widely used to mimic the extracellular matrix in bone tissue engineering, although they often lack biofunctional cues. In the authors' previous work, Potato virus X (PVX), a flexible rod‐shaped biocompatible plant virus nanoparticle (VNP) with 1270 coat protein subunits, is genetically modified to present functional peptides for generating a bone substitute. Here, PVX is engineered to present mineralization‐ and osteogenesis‐associated peptides and laden in hydrogels at a concentration lower by two orders of magnitude. Its competence in mineralization is demonstrated both on 2D surfaces and in hydrogels and the superiority of enriched peptides on VNPs is verified and compared with free peptides and VNPs presenting fewer functional peptides. Alkaline phosphatase activity and Alizarin red staining of human mesenchymal stem cells increase 1.2–1.7 times when stimulate by VNPs. Engineered PVX adheres to cells, exhibiting a stimulation of biomimetic peptides in close proximity to the cells. The retention of VNPs in hydrogels is monitored and more than 80% of VNPs remain inside after several washing steps. The mechanical properties of VNP‐laden hydrogels are investigated, including viscosity, gelling temperature, and compressive tangent modulus. This study demonstrates that recombinant PVX nanoparticles are excellent candidates for hydrogel nanocomposites in bone tissue engineering.
High‐Sensitivity Acoustic Molecular Sensors Based on Large‐Area, Spray‐Coated 2D Covalent Organic Frameworks
Authors: Evans Austin M. , Bradshaw Nathan P. , Litchfield Brian , Strauss Michael J. , Seckman Bethany , Ryder Matthew R. , Castano Ioannina , Gilmore Christopher , Gianneschi Nathan C. , Mulzer Catherine R. , Hersam Mark C. , Dichtel William R. 
Published: September 2020

Abstract2D covalent organic frameworks (2D COFs) are a unique materials platform that combines covalent connectivity, structural regularity, and molecularly precise porosity. However, 2D COFs typically form insoluble aggregates, thus limiting their processing via additive manufacturing techniques. In this work, colloidal suspensions of boronate‐ester‐linked 2D COFs are used as a spray‐coating ink to produce large‐area 2D COF thin films. This method is synthetically general, with five different 2D COFs prepared as colloidal inks and subsequently spray‐coated onto a diverse range of substrates. Moreover, this approach enables the deposition of multiple 2D COF materials simultaneously, which is not possible by polymerizing COFs on substrates directly. When combined with stencil masks, spray‐coated 2D COFs are rapidly deposited as thin films larger than 200 cm2 with line resolutions below 50 µm. To demonstrate that this deposition scheme preserves the desirable attributes of 2D COFs, spray‐coated 2D COF thin films are incorporated as the active material in acoustic sensors. These 2D‐COF‐based sensors have a 10 ppb limit‐of‐quantification for trimethylamine, which places them among the most sensitive sensors for meat and seafood spoilage. Overall, this work establishes a scalable additive manufacturing technique that enables the integration of 2D COFs into thin‐film device architectures.
Precise Control of Perovskite Crystallization Kinetics via Sequential A‐Site Doping
Authors: Qin Minchao , Xue Haibo , Zhang Hengkai , Hu Hanlin , Liu Kuan , Li Yuhao , Qin Zhaotong , Ma Junjie , Zhu Hepeng , Yan Keyou , Fang Guojia , Li Gang , Jeng U‐Ser , Brocks Geert , Tao Shuxia , Lu Xinhui 
Published: September 2020

AbstractTwo‐step‐fabricated FAPbI3‐based perovskites have attracted increasing attention because of their excellent film quality and reproducibility. However, the underlying film formation mechanism remains mysterious. Here, the crystallization kinetics of a benchmark FAPbI3‐based perovskite film with sequential A‐site doping of Cs+ and GA+ is revealed by in situ X‐ray scattering and first‐principles calculations. Incorporating Cs+ in the first step induces an alternative pathway from δ‐CsPbI3 to perovskite α‐phase, which is energetically more favorable than the conventional pathways from PbI2. However, pinholes are formed due to the nonuniform nucleation with sparse δ‐CsPbI3 crystals. Fortunately, incorporating GA+ in the second step can not only promote the phase transition from δ‐CsPbI3 to the perovskite α‐phase, but also eliminate pinholes via Ostwald ripening and enhanced grain boundary migration, thus boosting efficiencies of perovskite solar cells over 23%. This work demonstrates the unprecedented advantage of the two‐step process over the one‐step process, allowing a precise control of the perovskite crystallization kinetics by decoupling the crystal nucleation and growth process.
Monolithic Organic/Colloidal Quantum Dot Hybrid Tandem Solar Cells via Buffer Engineering
Authors: Kim Hong Il , Baek Se‐Woong , Choi Min‐Jae , Chen Bin , Ouellette Olivier , Choi Kyoungwon , Scheffel Benjamin , Choi Hyuntae , Biondi Margherita , Hoogland Sjoerd , García de Arquer F. Pelayo , Park Taiho , Sargent Edward H. 
Published: September 2020

AbstractMonolithically integrated hybrid tandem solar cells (TSCs) that combine solution‐processed colloidal quantum dot (CQD) and organic molecules are a promising device architecture, able to complement the absorption across the visible to the infrared. However, the performance of organic/CQD hybrid TSCs has not yet surpassed that of single‐junction CQD solar cells. Here, a strategic optical structure is devised to overcome the prior performance limit of hybrid TSCs by employing a multibuffer layer and a dual near‐infrared (NIR) absorber. In particular, a multibuffer layer is introduced to solve the problem of the CQD solvent penetrating the underlying organic layer. In addition, the matching current of monolithic TSCs is significantly improved to 15.2 mA cm−2 by using a dual NIR organic absorber that complements the absorption of CQD. The hybrid TSCs reach a power conversion efficiency (PCE) of 13.7%, higher than that of the corresponding individual single‐junction cells, representing the highest efficiency reported to date for CQD‐based hybrid TSCs.
Spiropyran‐Functionalized Polymer–Carbon Nanotube Hybrids for Dynamic Optical Memory Devices and UV Sensors
Authors: Balcı Leinen Merve , Klein Patrick , Sebastian Finn L. , Zorn Nicolas F. , Adamczyk Sylwia , Allard Sybille , Scherf Ullrich , Zaumseil Jana 
Published: September 2020

AbstractNanohybrids of purified semiconducting single‐walled carbon nanotubes and conjugated polymers with attached spiropyran moieties are created as photoresponsive materials for optical memory devices and ultraviolet (UV) light sensors. The hybrids respond to UV light exposure in air with photoisomerization of the spiropyran groups to merocyanine, resulting in significant and persistent p‐doping of the nanotubes, as confirmed by photoluminescence quenching and trion emission. The increased carrier concentration after illumination and the inherently high mobility of carbon nanotubes enable an up to two orders of magnitude increased conductivity of the nanotube/polymer hybrid networks in simple two‐terminal devices operated at very low bias. The photodoping decays very slowly in the dark and increases further with every illumination dose. However, it can be completely reversed by heating for a few seconds. Thin film devices based on these photoresponsive polymer/nanotube hybrids show great potential as simple and resettable UV dosimeters and optical memory elements.
Headaches in hypermobility syndromes: A pain in the neck?
Authors: Malhotra Anuj , Pace Anna , Ruiz Maya Tania , Colman Rachel , Gelb Bruce D. , Mehta Lakshmi , Kontorovich Amy R. 
Published: September 2020

AbstractHeadache and neck pain (cervicalgia) are frequently reported among patients with joint hypermobility but the prevalence and scope of these symptoms has not been studied in the era of contemporary Ehlers‐Danlos and hypermobility disorder nosology. We performed a single‐center retrospective study on the incidence of head and neck symptoms in 140 patients with hypermobility disorders over a 2‐year period. Overall, 93 patients (66%) reported either headache or neck pain with 49 of those (53%) reporting both. Migraine (83%) was the most common headache type among those with headache disorders and cervical spondylosis (61%) the most common pathology among those with neck symptoms. Fifty‐nine percent of spondylosis patients who underwent cervical facet procedures reported significant improvement in neck and head symptoms. Of patients with both head and neck complaints, 82% had both migraine and spondylosis, which, when combined with the high response rate to injections raises the possibility of cervicogenic headache. In this large multidisciplinary retrospective study of patients with hypermobility disorders, head and neck symptoms were highly prevalent, with migraine and cervical spondylosis common, often coexisting, and frequently responsive to targeted therapy for the cervical spine suggesting that degenerative spinal pathology may cause or contribute to headache symptoms in some patients with hypermobility disorders.
Investigating genetic correlation and causality between nicotine dependence and ADHD in a broader psychiatric context
Authors: Vink Jacqueline M. , Treur Jorien L. , Pasman Joëlle A. , Schellekens Arnt 
Published: September 2020

AbstractPeople with attention‐deficit/hyperactivity disorder (ADHD) or other psychiatric disorders show high rates of nicotine dependence (ND). This comorbidity might be (partly) explained by shared genetic factors. Genetic correlations between ND and ADHD (or other psychiatric disorders) have not yet been estimated. A significant genetic correlation might indicate genetic overlap, but could also reflect a causal relationship. In the present study we investigated the genetic correlation (with LD score regression analyses) between ND and ADHD, as well as between ND and other major psychiatric conditions (major depressive disorder, schizophrenia, anxiety, bipolar disorder, autism spectrum, anorexia nervosa, and antisocial behavior) based on the summary statistics of large Genome Wide Association studies. We explored the causal nature of the relationship between ND and ADHD using two‐sample Mendelian randomization. We found a high genetic correlation between ND and ADHD (rg = .53, p = 1.85 × 10−13), and to a lesser extent also between ND‐major depressive disorder (rg = .42, p = 3.6 × 10−11) and ND‐schizophrenia (rg = .18, p = 1.1 × 10−3). We did not find evidence for a causal relationship from liability for ADHD to ND (which could be due to a lack of power). The strong genetic correlations might reflect different phenotypic manifestations of (partly) shared underlying genetic vulnerabilities. Combined with the lack of evidence for a causal relationship from liability for ADHD to ND, these findings stress the importance to further investigate the underlying genetic vulnerability explaining co‐morbidity in psychiatric disorders.
A text mining analysis of perceptions of the COVID‐19 pandemic among final‐year medical students
Authors: Komasawa Nobuyasu , Terasaki Fumio , Nakano Takashi , Saura Ryuichi , Kawata Ryo 
Published: September 2020

AimThe coronavirus disease 2019 (COVID‐19) pandemic has presented various challenges to medical schools. We performed a text mining analysis via essay task to clarify perceptions among final‐year medical students toward the COVID‐19 pandemic.MethodsWe posed the following essay question to 124 final‐year medical students: “What should medical staff do during the COVID‐19 pandemic; what should you do?” Responses were subjected to quantitative analysis using a text mining approach. Frequently occurring key words were extracted, followed by multidimensional scaling and co‐occurrence network calculations.ResultsOf the 124 students, 123 (99.2%) responded to the essay question. The following seven key words were identified as high‐frequency words: medical, infection, patient, human, myself, doctor, and information. Co‐occurrence network calculations revealed that the word “medical” had a high degree of correlation with most key words, except for “doctor.” The word “myself” was correlated with not only “medical” but also “infection,” “human,” and “doctor.”ConclusionOur analysis of perceptions among final‐year medical students toward the COVID‐19 pandemic revealed that most medical students are strongly affected by the COVID‐19 pandemic and are motivated to work as physicians among health care professionals.
Mechanische Verstärkung von Coiled Coils mit Lactam und Histidin‐Metall‐Klammern
Authors: López‐García Patricia , de Araujo Aline D. , Bergues‐Pupo Ana E. , Tunn Isabell , Fairlie David P. , Blank Kerstin G. 
Published: September 2020

AbstractCoiled Coils (CCs) sind vielversprechende Proteinbausteine für biomimetische Materialien, die aufgrund ihrer mechanischen Eigenschaften vermehrt genutzt werden. In dieser Arbeit wurden Helix‐induzierende makrozyklische Klammern in ein CC‐Heterodimer eingefügt, um die thermodynamische und mechanische Stabilität dieses CCs zu erhöhen. Die thermodynamische Stabilisierung des CCs wird durch die Anzahl der Klammern bestimmt, während die mechanische Stabilisierung gegen Helixentfaltung primär von der Position der Klammer abhängt. Wird an einem Kraftangriffspunkt eine kovalente Lactam‐Klammer eingefügt, erhöht dies die Energiebarriere der Entfaltung und führt zu einer verringerten Deformierbarkeit der Helix. Eine reversible His‐Ni2+‐His Koordinationsklammer hingegen erhöht zwar die Energiebarriere, bricht jedoch bei hoher mechanischer Belastung und erlaubt so die Entfaltung der Helix vom Kraftangriffspunkt aus. Dies verdeutlicht, dass sowohl die Art der Klammer als auch ihre Position und Anzahl wichtige Schlüsselfaktoren für die Entwicklung von mechanisch stabilen CC‐Bausteinen für biomimetische Materialen darstellen.
Synthesis and characterization of dicyclic silicon‐/phosphorus‐grafted alumina and its application in improving flame retardancy of epoxy resin
Authors: Luo Xia , Hu Huan , Ma Jiajun , Huang Yawen , Yang Junxiao 
Published: September 2020

AbstractA new phosphorous/silicon/aluminum hybrid flame retardant (SAlu) was prepared by a surface grafting modification of alumina with a polymer (SDPS). The polymer was prepared by a condensation reaction between 3,9‐dichloro‐2,4,8,10‐tetrahydroxy‐3,9‐diphosphate heterocyclic‐3,9‐dioxide [5.5] undecane (SPDPC) and diphenyldisiloxol. The structure of the SAlu was further characterized by Fourier transform infrared spectroscopy, X‐ray diffraction, UV–Vis absorption, and particle size analysis. Thermogravimetric analysis showed that SPDS was grafted over 40% of the alumina surface. When introduced into epoxy resin, SAlu effectively improved the thermal stability and carbonization rate of the epoxy composites at high temperature. Carbonization studies showed that SAlu promoted formation of a ceramic‐carbon coking structure with a porous morphology of aggregates, which isolate combustible materials, heat, and oxygen. These features improved the flame retardant performance of the composite. The solidified materials were evenly dispersed in the network structure to improve the elastic deformation ability and glass transition temperature of the solidified resin.
Motion control for uniaxial rotational molding
Authors: Adams Jonathan , Jin Yan , Barnes David , Butterfield Joseph , Kearnes Mark 
Published: September 2020

AbstractMotion control parameters of rotational molding can affect process efficiency and product quality. Different motion control schemes will lead to varied powder flow regimes exhibiting different levels of mixing and temperature uniformity. The change in nature of powder flow during a molding cycle suggests that varying the rotational speed could improve the powder mixing and temperature uniformity, therefore potentially reducing processing time and energy consumption. Experiments completed investigating powder flow under uniaxial rotation show that savings of up to 2.5% of the heating cycle time can be achieved. This validates the hypothesis that altering the rotational speed to maintain the ideal powder flow throughout the heating cycle can be utilized to reduce the time taken for all the polymer powder to adhere to the mold wall. The effect of rotational speed on wall thickness uniformity and impact strength were investigated and discussed. Results show a strong influence of rotational speed (and powder flow) on the wall thickness uniformity of the moldings with wall thickness uniformity deviations of up to 50% found (within the 2–35 RPM speed range tested).