bluuebunny/crossref_metadata_2025 huggingface dataset:
Interfacial Covalent Bonds Regulated Electron‐Deficient 2D Black Phosphorus for Electrocatalytic Oxygen Reactions
Authors: Wang Xia , Raghupathy Ramya Kormath Madam , Querebillo Christine Joy , Liao Zhongquan , Li Dongqi , Lin Kui , Hantusch Martin , Sofer Zdeněk , Li Baohua , Zschech Ehrenfried , Weidinger Inez M. , Kühne Thomas D. , Mirhosseini Hossein , Yu Minghao , Feng Xinliang
Published: May 2021

Developing resource‐abundant and sustainable metal‐free bifunctional oxygen electrocatalysts is essential for the practical application of zinc–air batteries (ZABs). 2D black phosphorus (BP) with fully exposed atoms and active lone pair electrons can be promising for oxygen electrocatalysts, which, however, suffers from low catalytic activity and poor electrochemical stability. Herein, guided by density functional theory (DFT) calculations, an efficient metal‐free electrocatalyst is demonstrated via covalently bonding BP nanosheets with graphitic carbon nitride (denoted BP‐CN‐c). The polarized PN covalent bonds in BP‐CN‐c can efficiently regulate the electron transfer from BP to graphitic carbon nitride and significantly promote the OOH* adsorption on phosphorus atoms. Impressively, the oxygen evolution reaction performance of BP‐CN‐c (overpotential of 350 mV at 10 mA cm−2, 90% retention after 10 h operation) represents the state‐of‐the‐art among the reported BP‐based metal‐free catalysts. Additionally, BP‐CN‐c exhibits a small half‐wave overpotential of 390 mV for oxygen reduction reaction, representing the first bifunctional BP‐based metal‐free oxygen catalyst. Moreover, ZABs are assembled incorporating BP‐CN‐c cathodes, delivering a substantially higher peak power density (168.3 mW cm−2) than the Pt/C+RuO2‐based ZABs (101.3 mW cm−2). The acquired insights into interfacial covalent bonds pave the way for the rational design of new and affordable metal‐free catalysts.
Solution‐Processed Stretchable Ag2S Semiconductor Thin Films for Wearable Self‐Powered Nonvolatile Memory
Authors: Jo Seungki , Cho Soyoung , Yang U Jeong , Hwang Gyeong‐Seok , Baek Seongheon , Kim Si‐Hoon , Heo Seung Hwae , Kim Ju‐Young , Choi Moon Kee , Son Jae Sung
Published: April 2021

Compared with the large plastic deformation observed in ductile metals and organic materials, inorganic semiconductors have limited plasticity (<0.2%) due to their intrinsic bonding characters, restricting their widespread applications in stretchable electronics. Herein, the solution‐processed synthesis of ductile α‐Ag2S thin films and fabrication of all‐inorganic, self‐powered, and stretchable memory devices, is reported. Molecular Ag2S complex solution is synthesized by chemical reduction of Ag2S powder, fabricating wafer‐scale highly crystalline Ag2S thin films. The thin films show stretchability due to the intrinsic ductility, sustaining the structural integrity at a tensile strain of 14.9%. Moreover, the fabricated Ag2S‐based resistive random access memory presents outstanding bipolar switching characteristics (Ion/Ioff ratio of ≈105, operational endurance of 100 cycles, and retention time >106 s) as well as excellent mechanical stretchability (no degradation of properties up to stretchability of 52%). Meanwhile, the device is highly durable under diverse chemical environments and temperatures from −196 to 300 °C, especially maintaining the properties for 168 h in 85% relative humidity and 85 °C. A self‐powered memory combined with motion sensors for use as a wearable healthcare monitoring system is demonstrated, offering the potential for designing high‐performance wearable electronics that are usable in daily life in a real‐world setting.
Reorientation and Flow of Liquid Crystal for a Pressure Sensor Using Carbon Nanotube Sheets
Authors: Murali Meenu , Rahman MD Asiqur , Scalia Giusy
Published: May 2021

The network formation of carbon nanotubes (CNTs) and the viscoelasticity of liquid crystals (LCs) are synergetic properties that enable the formation of composites very sensitive to external pressure. Using a layered structure with nematic LCs and anisotropic networks formed by highly aligned multiwall CNT sheets, the pressure sensor capability of such structure and its piezoresistive response are demonstrated. The application of pressure on the upper substrate is transmitted via LC elastic deformation and flow onto the underlying CNT sheets, improving the electrical conductance. The fabrication process here is relatively facile and versatile as stretched CNT sheets can be easily transferred to any chosen substrate. The sensor response is linear with decrease of 2.42 Ω kPa−1 as the pressure value increases and it is reversible. The sensitivity depends on the thickness of the overlying LC layer and by its relative change, affected by the spacers during force application, but also on the electrical characteristics of the CNTs. The highest sensitivity is obtained with one single CNT sheet and the responsiveness decreases with the increase of number of layers due to the smaller influence of the LC on the contact resistance of the CNT sheets.
Stabilizing Black Phosphorus via Covalent Functionalization of Solvent Formamide
Authors: He Zuoliang , Liu Rui , Shan Wanyu , Zhao Huachao , Lai Yujian , Li Peng , Liu Jingfu
Published: May 2021

Black phosphorus (BP) has been attracting increasing scientific and technological interest for its excellent materials properties, but suffers from the intrinsic easy oxidization due to the high reactivity of lone‐pair electrons in each phosphorus atom. Herein, solvent formamide (FM) is proposed for the covalent modification of BP by a one‐step ultrasonication without any additive. FM is demonstrated to functionalize BP by the formation of single covalent bond PN, thus occupying the active lone‐pair electrons of P atoms and leading to the significant enhancement of the antioxidative capacity of BP. Density functional theory calculations also rationalize the formation of stable PN bond and its contribution to the high solvent‐exfoliated efficiency during the exfoliation of BP. The plausible reaction mechanism of FM with BP and the final 5‐membered ring structure of products are also proposed to explain the formation process of the stable PN bonds.
The Materials Science Foundation Supporting the Microfabrication of Reliable Polyimide–Metal Neuroelectronic Interfaces
Authors: Kuliasha Cary A. , Judy Jack W.
Published: May 2021

Thin‐film polyimide–metal neuroelectronic interfaces hold the potential to alleviate many neurological disorders. However, their long‐term reliability is challenged by an aggressive implant environment that causes delamination and degradation of critical materials, resulting in a degradation or complete loss of implant function. Herein, a rigorous and in‐depth analysis is presented on the fabrication and modification of critical materials in these thin‐film neural interfaces. Special attention is given to improving the interfacial adhesion between thin films and processing modifications to maximize device reliability. Fundamental material analyses are performed on the polyimide substrate and adhesion‐promotion candidates, including amorphous silicon carbide (a‐SiC:H), amorphous carbon, and silane coupling agents. Basic fabrication rules are identified to markedly improve polyimide self‐adhesion, including optimizing the polyimide‐cure profile and maximizing high‐energy surface activation. In general, oxide‐forming materials are identified as poor adhesive aids to polyimide without targeted modifications. Methods are identified to incorporate effective a‐SiC:H interfacial layers to improve metal adherence to polyimide, in addition to examples of alloying between adjacent material layers that can impact the trace resistivity and long‐term reliability of the thin‐film interfaces. The provided rationale and consequences of key decisions made should promote more reproducible science using robust and reliable neuroelectronic technology.
A Highly Programmable Magnetic Micropump
Authors: Peng Xing Yue (Larry) , Peng Linghan , Guo Yaxin
Published: May 2021

A cheap, small, convenient, reliable, and durable lab‐on‐a‐chip is needed for various scenarios in practical applications. The authors hope to use the chip only after plugging in a mobile phone. An ideal micropump design is obtained by simplifying the micropump theory, reducing the micropump to 1 mm (oscillator pump, O‐pump), the external device (actuator) to 5 mm, and the power to 10 mW. This system costs ≈$10 and can work in harsh fluid environments (such as animal cell culture) for an extended period (a few months of testing). An MP3 player drives two O‐pumps by a programmable playlist. The O‐pump is a permanent magnet positive sphere in an open fluid space, which is not easy to block and rolls freely without wear. Only controlled by the magnetic field, the O‐pump avoids interference from the current, electric field, and chemical activity. The fluid is driven by a vibrating motion, in open or sealed channels, with no unique materials and no other equipment. The debris, bubbles, and fibers in the blood viscosity fluid do not affect the pump's function. The system can be applied in different scenarios, such as the automatic cultivation of stem cells or point‐of‐care devices.
Rhodium‐Catalyzed C−H Activation/Annulation Cascade of Aryl Oximes and Propargyl Alcohols to Isoquinoline N‐Oxides
Authors: Li Yuan , Fang Feifei , Zhou Jianhui , Li Jiyuan , Wang Run , Liu Hong , Zhou Yu
Published: April 2021

A β‐hydroxy elimination instead of common oxidization to carbonyl group in secondary propargyl alcohols was successfully developed to form 2‐benzyl substituted isoquinoline N‐oxides by a Rhodium‐catalyzed C−H activation and annulation cascade, in which moderate to excellent yields (up to 92%) could be obtained under mild reaction conditions, along with good regioselectivity, broad generality and applicability.

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Comparison of Adsorption Conformation of Comb‐Shaped Polycarboxylate on Tricalcium Aluminate (100) and Ettringite (100) Surfaces: A Molecular Dynamics Study
Authors: Zhao Hongxia , Yang Yong , Shu Xin , Wang Tao , Ran Qianping
Published: April 2021

The adsorption conformations of three comb‐shaped polycarboxylate (PCE) with different numbers of grafted side‐chains on the tricalcium aluminate (C3A) and ettringite surface is studied by all‐atom molecular dynamics (MD) simulations with INTERFACE‐PCFF forcefield. The similarity of absorbed PCEs on both surfaces is backbones of PCEs absorbed on the surface and the side‐chains extended to liquid phase. The difference is that side‐chains of PCEs keep a tilt angle with the C3A crystal but maintain parallel and closer to ettringite crystals. The absolute value of adsorption energy of PCEs on C3A surface is greater than that on ettringite surface, which indicate the stronger interaction between PCEs and C3A than ettringite. PCE with less side chains is favorable for the adsorption due to stronger electrostatic interaction with surface. Adsorption capacity and water‐reducing ability of PCEs are contradictory. Density of water near the solid–liquid interface is more severely decreased by PCE with more side chains. Correlation of the adsorption conformation of PCEs with the flow behaviors of fresh cement paste is summarized.
Silver Covalently Bound to Cyanographene Overcomes Bacterial Resistance to Silver Nanoparticles and Antibiotics
Authors: Panáček David , Hochvaldová Lucie , Bakandritsos Aristides , Malina Tomáš , Langer Michal , Belza Jan , Martincová Jana , Večeřová Renata , Lazar Petr , Poláková Kateřina , Kolařík Jan , Válková Lucie , Kolář Milan , Otyepka Michal , Panáček Aleš , Zbořil Radek
Published: May 2021

The ability of bacteria to develop resistance to antibiotics is threatening one of the pillars of modern medicine. It was recently understood that bacteria can develop resistance even to silver nanoparticles by starting to produce flagellin, a protein which induces their aggregation and deactivation. This study shows that silver covalently bound to cyanographene (GCN/Ag) kills silver‐nanoparticle‐resistant bacteria at concentrations 30 times lower than silver nanoparticles, a challenge which has been so far unmet. Tested also against multidrug resistant strains, the antibacterial activity of GCN/Ag is systematically found as potent as that of free ionic silver or 10 nm colloidal silver nanoparticles. Owing to the strong and multiple dative bonds between the nitrile groups of cyanographene and silver, as theory and experiments confirm, there is marginal silver ion leaching, even after six months of storage, and thus very high cytocompatibility to human cells. Molecular dynamics simulations suggest strong interaction of GCN/Ag with the bacterial membrane, and as corroborated by experiments, the antibacterial activity does not rely on the release of silver nanoparticles or ions. Endowed with these properties, GCN/Ag shows that rigid supports selectively and densely functionalized with potent silver‐binding ligands, such as cyanographene, may open new avenues against microbial resistance.
The m6A Reader IGF2BP2 Regulates Macrophage Phenotypic Activation and Inflammatory Diseases by Stabilizing TSC1 and PPARγ
Authors: Wang Xia , Ji Yuge , Feng Panpan , Liu Rucheng , Li Guosheng , Zheng Junjie , Xue Yaqiang , Wei Yaxun , Ji Chunyan , Chen Dawei , Li Jingxin
Published: May 2021

Phenotypic polarization of macrophages is regulated by a milieu of cues in the local tissue microenvironment. Currently, little is known about how the intrinsic regulators modulate proinflammatory (M1) versus prohealing (M2) macrophages activation. Here, it is observed that insulin‐like growth factor 2 messenger RNA (mRNA)‐binding protein 2 (IGF2BP2)‐deleted macrophages exhibit enhanced M1 phenotype and promote dextran sulfate sodium induced colitis development. However, the IGF2BP2−/− macrophages are refractory to interleukin‐4 (IL‐4) induced activation and alleviate cockroach extract induced pulmonary allergic inflammation. Molecular studies indicate that IGF2BP2 switches M1 macrophages to M2 activation by targeting tuberous sclerosis 1 via an N6‐methyladenosine (m6A)‐dependent manner. Additionally, it is also shown a signal transducer and activators of transcription 6 (STAT6)‐high mobility group AT‐hook 2‐IGF2BP2‐peroxisome proliferator activated receptor‐γ axis involves in M2 macrophages differentiation. These findings highlight a key role of IGF2BP2 in regulation of macrophages activation and imply a potential therapeutic target of macrophages in the inflammatory diseases.
Cyclic Arginine–Glycine–Aspartate‐Decorated Lipid Nanoparticle Targeting toward Inflammatory Lesions Involves Hitchhiking with Phagocytes
Authors: Sofias Alexandros Marios , Bjørkøy Geir , Ochando Jordi , Sønstevold Linda , Hegvik Maria , Davies Catharina de Lange , Haraldseth Olav , Lammers Twan , Mulder Willem J. M. , Hak Sjoerd
Published: May 2021

Active‐targeting nanomedicine formulations have an intricate in vivo behavior. Nanomedicines developed to target endothelial αvβ3‐integrin are recently demonstrated to display extensive uptake by circulating phagocytes. These phagocytes show inherent tumor‐homing capacities and therefore are capable of actively delivering the endocytosed nanomaterial in lesions. Here, the targeting kinetics and mechanisms of cyclic arginine–glycine–aspartate (cRGD)‐decorated lipid nanoparticles (NPs) toward activated vasculature in inflamed lesions during wound healing are studied. The cRGD‐NP targeting toward inflamed lesions is identified to be mechanistically similar to the NP accumulation in cancerous lesions. Through a complementary experimental approach, it is observed that circulating phagocytes engage cRGD‐NPs and are subsequently homed to the inflamed endothelium. The inflammation‐associated phagocytes remain static among endothelial cells upon targeting, resulting in the extensive presence of cRGD‐NP‐positive phagocytes in the angiogenic vessels. Hence, phagocytic immune cells contribute to cRGD‐NP targeting toward angiogenesis. This mechanistic study underlines the need for detailed investigations of NP in vivo behavior. This is critically important for the realization of NPs potential as advanced (immunological) therapeutic agents.
Cooperative organizations of small molecular surfactants and amphiphilic block copolymers: Roles of surfactants in the formation of binary co‐assemblies
Authors: Cao Yuanyuan , Yang Shaobo , Li Yongsheng , Shi Jianlin
Published: May 2021

The construction of highly ordered organizations through self‐assembly is one of the most popular phenomena both in natural and artificial environments. Amphiphilic molecules are the most commonly used building blocks for the self‐assembly, which are conventionally known as amphiphilic low molecular weight surfactants with polar heads and nonpolar tails, or amphiphilic block copolymers (BCPs) consisting of covalently bonded hydrophilic and hydrophobic block chains. Compared with single surfactant self‐assembly system, binary amphiphiles co‐assembly systems composing of both small mass surfactants and amphiphilic BCPs feature high flexibilities and versatilities in materials designing and structure regulation, ascribing to the vast possibilities of intermolecular interactions within the systems and facile component modulations during the assembly processes. The amphiphilic features of the two kinds of molecules endow them with similar self‐assembly behaviors, while the unique and distinct characters of each kind of amphiphiles lead to various complex but highly diversified co‐assembly systems. According to the roles of the surfactant played in the co‐assembly system, in this review, we summarize the binary co‐assembly systems from three distinct types: 1) the co‐micellization system in which the surfactants are added into the BCPs assemblies as a self‐assembly assistant; 2) the co‐emulsification system in which the surfactants work as an emulsion stabilizer to assist and confine the assembly of BCPs in 3D geometries; 3) the co‐templating system where the individual micelles of both surfactant and BCPs are hierarchically arranged and distributed to guide the formation of hierarchical nanomaterials. Following this, the major potential applications of the nanomaterials synthesized from the binary amphiphiles in biological field are described. Finally, we shortly discuss the current challenges and future perspectives of the binary amphiphiles self‐assembly systems.
Diagnostic value of D‐dimers for limb deep vein thrombosis in children: A prospective study
Authors: Avila Laura , Amiri Nour , Pullenayegum Eleanor , Sealey Victoria Abigail , De Riddhita , Williams Suzan , Vincelli Jennifer , Brandão Leonardo R.
Published: April 2021

The present study sought to evaluate the discriminative and predictive ability of D‐dimer for pediatric limb DVT. Children aged 28 days–18 years requiring imaging to rule out limb DVT, as per the treating clinical team, were enrolled in the study. The outcome was ultrasound proven DVT. The D‐dimer levels were obtained around the time of imaging. Receiver operating characteristic (ROC) curves and logistic regression models were used for data analyses. In total, 296 patients were enrolled between 2017–2020; 204 patients were diagnosed with DVT (DVT[+]). Median D‐dimer levels were 2.3 μg/ml FEU (25th–75th percentile 0.9–3.9) among DVT(+) and 1.9 μg/ml FEU (25th–75th percentile 0.8–4.0) among DVT(−) patients (p = 0.60). The area under the ROC curve (AUC) was 0.52 (95% confidence interval [CI] 0.45–0.59). The odds ratio for D‐dimer levels was 1.00 (95% CI 0.99–1.01), holding confounders constant. In a sub‐group exploratory analysis including 23 patients with no underlying conditions or co‐morbidities, the AUC curve was 0.90 (95% CI 0.76–1.00). In conclusion, in this prospective cohort study of consecutive children with suspected limb DVT, D‐dimer levels had poor discriminative and predictive ability for DVT. However, D‐dimer levels showed better discriminative and predictive ability for DVT in an exploratory sample of patients with no underlying conditions or co‐morbidities at the time of diagnosis.
Sex differences in anxiety and depression in children with attention deficit hyperactivity disorder: Investigating genetic liability and comorbidity
Authors: Martin Joanna , Shameem Agha Sharifah , Eyre Olga , Riglin Lucy , Langley Kate , Hubbard Leon , Stergiakouli Evie ,   Psychiatric Genomics Consortium ADHD Working Group, O'Donovan Michael , Thapar Anita
Published: May 2021

It is unknown why attention deficit hyperactivity disorder (ADHD) is more common in males, whereas anxiety and depression show a female population excess. We tested the hypothesis that anxiety and depression risk alleles manifest as ADHD in males. We also tested whether anxiety and depression in children with ADHD show a different etiology to typical anxiety and depression and whether this differs by sex. The primary clinical ADHD sample consisted of 885 (14% female) children. Psychiatric symptoms were assessed using standardized interviews. Polygenic risk scores (PRS) were derived using large genetic studies. Replication samples included independent clinical ADHD samples (N = 3,794; 25.7% female) and broadly defined population ADHD samples (N = 995; 33.4% female). We did not identify sex differences in anxiety or depression PRS in children with ADHD. In the primary sample, anxiety PRS were associated with social and generalized anxiety in males, with evidence of a sex‐by‐PRS interaction for social anxiety. These results did not replicate in the broadly defined ADHD sample. Depression PRS were not associated with comorbid depression symptoms. The results suggest that anxiety and depression genetic risks are not more likely to lead to ADHD in males. Also, the evidence for shared etiology between anxiety symptoms in those with ADHD and typical anxiety was weak and needs replication.
Enabling Lithium Metal Anode in Nonflammable Phosphate Electrolyte with Electrochemically Induced Chemical Reactions
Authors: Zhang Haochuan , Luo Jingru , Qi Miao , Lin Shiru , Dong Qi , Li Haoyi , Dulock Nicholas , Povinelli Christopher , Wong Nicholas , Fan Wei , Bao Junwei Lucas , Wang Dunwei
Published: April 2021

Lithium metal anode holds great promises for next‐generation battery technologies but is notoriously difficult to work with. The key to solving this challenge is believed to lie in the ability of forming stable solid‐electrolyte interphase (SEI) layers. To further address potential safety issues, it is critical to achieve this goal in nonflammable electrolytes. Building upon previous successes in forming stable SEI in conventional carbonate‐based electrolytes, here we report that reversible Li stripping/plating could be realized in triethyl phosphate (TEP), a known flame retardant. The critical enabling factor of our approach was the introduction of oxygen, which upon electrochemical reduction induces the initial decomposition of TEP and produces Li3PO4 and poly‐phosphates. Importantly, the reaction was self‐limiting, and the resulting material regulated Li plating by limiting dendrite formation. In effect, we obtained a functional SEI on Li metal in a nonflammable electrolyte. When tested in a symmetric Li∥Li cell, more than 300 cycles of stripping/plating were measured at a current density of 0.5 mA cm−2. Prototypical Li‐O2 and Li‐ion batteries were also fabricated and tested to further support the effectiveness of this strategy. The mechanism by which the SEI forms was studied by density functional theory (DFT), and the predictions were corroborated by the successful detection of the intermediates and products.
High‐Energy‐Density Magnesium‐Air Battery Based on Dual‐Layer Gel Electrolyte
Authors: Li Luhe , Chen Hao , He Er , Wang Lie , Ye Tingting , Lu Jiang , Jiao Yiding , Wang Jiacheng , Gao Rui , Peng Huisheng , Zhang Ye
Published: April 2021

Mg‐air batteries are explored as the next‐generation power systems for wearable and implantable electronics as they could work stably in neutral electrolytes and are also biocompatible. However, high corrosion rate and low utilization of Mg anode largely impair the performance of Mg‐air battery with low discharge voltage, poor specific capacity and low energy density. Here, to the best of our knowledge, we first report a dual‐layer gel electrolyte to simultaneously solve the above two problems by preventing the corrosion of Mg anode and the production of dense passive layer, respectively. The resulting Mg‐air batteries produced an average specific capacity of 2190 mAh g−1 based on the total Mg anode (99.3 % utilization rate of Mg anode) and energy density of 2282 Wh kg−1 based on the total anode and air electrode, both of which are the highest among the reported Mg‐air batteries. Besides, our Mg‐air batteries could be made into a fiber shape, and they were flexible to work stably under various deformations such as bending and twisting.
Liquid‐Phase Synthesis of Highly Reactive Rare‐Earth Metal Nanoparticles
Authors: Bartenbach Daniel , Wenzel Olivia , Popescu Radian , Faden Lara‐Pauline , Reiß Andreas , Kaiser Michelle , Zimina Anna , Grunwaldt Jan‐Dierk , Gerthsen Dagmar , Feldmann Claus
Published: April 2021

The first liquid‐phase synthesis of high‐quality, small‐sized rare‐earth metal nanoparticles (1–3 nm)—ranging from lanthanum as one of the largest (187 pm) to scandium as the smallest (161 pm) rare‐earth metal—is shown. Size, oxidation state, and reactivity of the nanoparticles are examined (e.g., electron microscopy, electron spectroscopy, X‐ray absorption spectroscopy, selected reactions). Whereas the nanoparticles are highly reactive (e.g. in contact to air and water), they are chemically stable as THF suspensions and powders under inert conditions. The reactivity can be controlled to obtain inorganic and metal–organic compounds at room temperature.
Spectroscopic, thermodynamic and ultrasonic properties of pseudo‐binary mixtures of organic extractants and vegetable oil at 25–60°C under atmospheric pressure
Authors: Sarkar Soumi , Mondal Supriyo Kumar , Beriya Manoj Kumar , Saha Prabirkumar
Published: May 2021

This work is intended to investigate the molecular interactions and transport properties of five pseudo‐binary mixtures of various combinations of vegetable oils (sesame oil and sunflower oil) and organic extractants (Aliquat 336, TBP, D2EHPA and TOA) by determining their surface tension, density and viscosity over a temperature range of 25–60°C at atmospheric pressure. The experimental data are fitted into various literature models. Information on excess molar volume and viscosity deviation leads to an understanding of solute–solvent interactions. Further, the ultrasonic velocity, isentropic compressibility, intermolecular free length, specific impedance, apparent molar volume, volumetric thermal expansion coefficient, excess Gibbs' free energy, change in enthalpy of mixing and entropy of activation of the liquids have been calculated. A model relating the surface tension, density and viscosity of the pseudo‐binary mixtures has been proposed in this paper. Analysis of Fourier transform infrared (FTIR) studies has further illustrated the intermolecular interactions in the pseudo‐binary mixtures.
3D printing of shape memory polymers
Authors: Ehrmann Guido , Ehrmann Andrea
Published: May 2021

Shape memory polymers (SMPs) are polymers which ''remember'' their original shape and can return to it after deformation, if an external stimulus—often an increased temperature – is applied. Some SMPs can be 3D printed, typically by fused deposition modeling (FDM). The most well‐known SMP is poly(lactic acid), which belongs to the most often used materials in FDM 3D printing. There are; however, many more SMPs which can be 3D printed to combine the possibilities to prepare new, sophisticated shapes with the opportunity to restore these shapes after undesirable or intentional deformation. This review gives an overview of several 3D printable SMPs, their mechanical characteristics and their possible applications.
Estimating herbarium specimen digitization rates: Accounting for human experience
Authors: Powell Caleb , Krakowiak Alaina , Fuller Rachel , Rylander Erica , Gillespie Emily , Krosnick Shawn , Ruhfel Brad , Morris Ashley B. , Shaw Joey
Published: April 2021

Premise

Herbaria are invaluable sources for understanding the natural world, and in recent years there has been a concerted effort to digitize these collections. To organize such efforts, a method for estimating the necessary labor is desired. This work analyzes digitization productivity reports of 105 participants from eight herbaria, deriving generalized labor estimates that account for human experience.

Methods and Results

Individuals’ rates of digitization were grouped based on cumulative time performing each task and then used to estimate a series of generalized labor projection models. In most cases, productivity was shown to improve with experience, suggesting longer technician retention can reduce labor requirements by 20%.

Conclusions

Using student labor is a common tactic for digitization efforts, and the resulting outreach exposes future professionals to natural history collections. However, overcoming the learning curve should be considered when estimating the labor necessary to digitize a collection.
Predicting Dinitrogen Activation via Transition‐Metal‐Involved [4+2] Cycloaddition Reaction
Authors: Dong Shicheng , Zhu Jun
Published: May 2021

As the strongest triple bond in nature, the N≡N triple bond activation has always been a challenging project in chemistry. On the other hand, since the award of the Nobel Prize in Chemistry in 1950, the Diels‐Alder reaction has served as a powerful and widely applied tool in the synthesis of natural products and new materials. However, the application of the Diels‐Alder reaction to dinitrogen activation remains less developed. Here we first demonstrate that a transition‐metal‐involved [4+2] Diels‐Alder cycloaddition reaction could be used to activate dinitrogen without an additional reductant by density functional theory calculations. Further study reveals that such a dinitrogen activation by 1‐metalla‐1,3‐dienes screened out from a series of transition metal complexes (38 species) according to the effects of metal center, ligand, and substituents can become favorable both thermodynamically (with an exergonicity of 28.2 kcal mol−1) and kinetically (with an activation energy as low as 13.8 kcal mol−1). Our findings highlight an important application of the Diels‐Alder reaction in dinitrogen activation, inviting experimental chemists’ verification.
Pharmacokinetic comparisons of six steroid saponins in rat plasma following oral administration of crude and stir‐fried Fructus Tribuli extracts by UHPLC–MS/MS
Authors: Song Xiao , Yuan Yaohui , Wang Shuyue , Sun Xiaochen , Zhang Chao , Gao Peng , Shi Lei
Published: May 2021

Modern pharmacological studies have shown that Fructus Tribuli can improve sexual function and treat cardiovascular diseases. In this study, we focused on comparing the pharmacokinetics of crude Fructus Tribuli (CFT) and stir‐fried Fructus Tribuli (SFT) to further clarify the changes in chemical composition in vivo. The quantitation of six analytes was performed in a triple quadrupole mass spectrometer using the multiple reaction monitoring mode. Separation was performed on a Halo® C18 column using 0.05% formic acid and 5 μmol/L sodium formate in water, and 0.05% formic acid and 5 μmol/L sodium formate in acetonitrile as the mobile phase. The selectivity, precision, accuracy, extraction recovery, matrix effect and stability of the method were fully validated. Compared with the crude group, the parameters Cmax and AUC0–t of terrestroside B and terrestrosin K increased significantly (P < 0.05), but the Cmax and AUC0–t of polianthoside D, terrestrinin D, tribuluside A and terrestrosin D were decreased, terrestrosin D being especially decreased (P < 0.05), after oral administration of SFT extract. These results showed that the developed method was suitable for pharmacokinetic analysis of the six steroid saponins of CFT and SFT in rat plasma, and can be used to facilitate future clinical studies.
Embryonic ethanol exposure on zebrafish early development
Authors: Pinheiro‐da‐Silva Jaquelinne , Luchiari Ana Carolina
Published: May 2021

Introduction

Embryonic exposure to ethanol leads to a condition of physical, behavioral, and cognitive deficiencies named fetal alcohol spectrum disorders (FASD). The most severe variations are in fetal alcohol syndrome (FAS), which is easier to diagnose and not studied in animal models. On the other side, the pFAS (partial fetal alcohol syndrome) includes cases of alcohol‐related congenital disabilities and neurodevelopmental disorder with an inconclusive diagnosis. In recent years, the zebrafish has become a valuable model to study FASD and its variations.

Methods

This study characterizes the zebrafish embryonic and larval development after low and moderate ethanol concentration exposure. Fish eggs were exposed to 0.0%, 0.25%, 0.5%, and 1.0% ethanol at 24 hr postfertilization, and embryonic development was observed every 8 hr up to 120 hpf. It evaluated movements, phenotypic abnormalities, hatching, cardiac function and heartbeat frequency, larvae length at 120 hpf, and the apoptotic cells' fluorescence stained with acridine orange.

Results

Embryonic exposure to 0.5% and 1% ethanol presented reduced body size, decreased heartbeat rate, higher numbers of apoptotic cells, and hatching time differences.

Conclusions

Our results suggest any ethanol exposure during embryogenesis can be harmful and reinforces zebrafish as a suitable model for fetal alcohol spectrum disorders (FASD).
Data mining of an acoustic biomarker in tongue cancers and its clinical validation
Authors: Xiao Yudong , Wang Tao , Deng Wei , Yang Le , Zeng Bin , Lao Xiaomei , Zhang Sien , Liu Xiangqi , Ouyang Daiqiao , Liao Guiqing , Liang Yujie
Published: May 2021

The promise of speech disorders as biomarkers in clinical examination has been identified in a broad spectrum of neurodegenerative diseases. However, to the best of our knowledge, a validated acoustic marker with established discriminative and evaluative properties has not yet been developed for oral tongue cancers. Here we cross‐sectionally collected a screening dataset that included acoustic parameters extracted from 3 sustained vowels /ɑ/, /i/, /u/ and binary perceptual outcomes from 12 consonant‐vowel syllables. We used a support vector machine with linear kernel function within this dataset to identify the formant centralization ratio (FCR) as a dominant predictor of different perceptual outcomes across gender and syllable. The Acoustic analysis, Perceptual evaluation and Quality of Life assessment (APeQoL) was used to validate the FCR in 33 patients with primary resectable oral tongue cancers. Measurements were taken before (pre‐op) and four to six weeks after (post‐op) surgery. The speech handicap index (SHI), a speech‐specific questionnaire, was also administrated at these time points. Pre‐op correlation analysis within the APeQoL revealed overall consistency and a strong correlation between FCR and SHI scores. FCRs also increased significantly with increasing T classification pre‐operatively, especially for women. Longitudinally, the main effects of T classification, the extent of resection, and their interaction effects with time (pre‐op vs. post‐op) on FCRs were all significant. For pre‐operative FCR, after merging the two datasets, a cut‐off value of 0.970 produced an AUC of 0.861 (95% confidence interval: 0.785–0.938) for T3‐4 patients. In sum, this study determined that FCR is an acoustic marker with the potential to detect disease and related speech function in oral tongue cancers. These are preliminary findings that need to be replicated in longitudinal studies and/or larger cohorts.
First‐line therapy of bevacizumab plus chemotherapy versus cetuximab plus chemotherapy for metastatic colorectal cancer patients with mucinous adenocarcinoma or mucinous component
Authors: Zhou Yu‐Wen , Long Yi‐Xiu , Chen Ye , Liu Ji‐Yan , Pu Dan , Huang Jia‐Yan , Bi Feng , Li Qiu , Gou Hong‐Feng , Qiu Meng
Published: May 2021

Background

To compare the efficacy of first‐line bevacizumab plus chemotherapy with cetuximab plus chemotherapy based on the stratification of metastatic colorectal cancer (mCRC) patients with mucinous adenocarcinoma (MA) or mucinous component (MC).

Methods

A retrospective study involving all mCRC patients receiving first‐line bevacizumab‐based or cetuximab‐based chemotherapy at our hospital from September 2013 to January 2020 was conducted. Overall survival (OS), progression‐free survival (PFS), and objective response rate (ORR) were compared between the cetuximab‐chemotherapy group and the bevacizumab‐chemotherapy group on the basis of the conventional pathological classification of MA or MC.

Results

A total of 620 patients with mCRC were included in our study, consisting of 141 (22.7%) patients with MA/MC and 479 (77.3%) patients with non‐mucinous adenocarcinoma (NMA). In the MA/MC cohort, patients who were treated with bevacizumab‐based chemotherapy were associated with significantly better OS than those treated with cetuximab‐base chemotherapy (30.0 vs. 26.3 months, p = 0.002), irrespective of tumor sites. The efficacy of bevacizumab‐based chemotherapy was higher in nearly all subgroups as shown in the subgroup analysis. In the NMA cohort, median OS was better in the cetuximab plus chemotherapy group than that in the bevacizumab plus chemotherapy group (32.2 vs. 27.0 months, p = 0.005) for left‐side mCRC patients, whereas OS was significantly longer in the bevacizumab plus chemotherapy group for right‐side mCRC patients (26.0 vs. 20.9 months, p = 0.013).

Conclusion

Conventional pathological classification (e.g. MA/MC) should be considered when tailoring the individualized optimal treatment for mCRC. Bevacizumab plus chemotherapy as first‐line therapy may be the optimal option for patients with MA/MC.
A rare cause of lumbar nerve root compression: Extramedullary hematopoiesis in a patient with thalassemia major
Authors: Boussaa Hiba , Kaffel Dhia , Maatallah Kaouther , Lassoued Ferjani Hanene , Hamdi Wafa
Published: May 2021

Extramedullary hematopoiesis (EMH) can rarely involve the epidural space, leading to spinal cord compression syndrome. No treatment guidelines have been established yet.
Two‐Dimensional Guanidine‐Based Hybrid Perovskites with Strong Dichroism for Multiwavelength Polarization‐Sensitive Detection
Authors: Lu Lei , Ma Yu , Wang Jiaqi , Liu Yi , Han Shiguo , Liu Xitao , Guo Wuqian , Xu Haojie , Luo Junhua , Sun Zhihua
Published: April 2021

Two‐dimensional (2D) organic–inorganic hybrid perovskites, benefiting from their natural anisotropy of quantum‐well motifs and optical properties, have shown remarkable polarization‐dependent responses superior to the 3D counterparts. Here, for the first time, multiwavelength polarization‐sensitive detectors were fabricated by using single crystals of a guanidine‐based 2D hybrid perovskite, (BA)2(GA)Pb2I7 (where BA+ is n‐butylammonium and GA+ is guanidium). Its unique 2D quantum‐well structure results in strong crystallographic‐dependence of optical absorption. Strikingly, our crystal‐based photodetector exhibits a prominent photocurrent dichroic ratio (Imax/Imin) of ∼2.2 at 520 nm, higher than the typical 2D inorganic materials (GeSe, ∼1.09, PdSe2, ∼1.8). In addition, notable dichroic ratios of 1.29 and 1.23 at 405 nm and 637 nm are also created for the multiwavelength polarized‐light detection. The prominent detecting performances, including low dark current (1.6×10−11 A), considerable on/off ratio (∼2×103), high photodetectivity (∼3.3×1011 Jones) and responsivity (∼12.01 mA W−1), make (BA)2(GA)Pb2I7 a promising candidate for polarized‐light detection. This work sheds light on the rational engineering of new 2D hybrid perovskites for the high‐performance optoelectronic device applications.
CeO2/TiO2/SiO2 nanocatalyst for the photocatalytic and sonophotocatalytic degradation of chlorpyrifos
Authors: Mansourian Reza , Mousavi Seyedeh Maryam , Alizadeh Shahin , Sabbaghi Samad
Published: May 2021

A new nanohybrid photocatalyst named cerium (IV) oxide (CeO2)/TiO2 (titania)/silicon dioxide (SiO2) was firstly synthesized employing the co‐precipitation technique to elaborate the degradation efficiency of chlorpyrifos (CPS) as a relatively indelible organophosphorus pesticide in deionized water in photocatalytic and sonophotocatalytic processes. The influence of various parameters, including photocatalyst dosage, the CPS pesticide concentration, pH, and irradiation time, was investigated, and the optimal parameters for photodegradation and sonophotodegradation were determined. The activity and the electrical energy of this photocatalyst in the photodegradation and sonophotodegradation processes were compared, and it was revealed that the sonophotocatalytic process was superior to the photocatalytic one (about 15%). Results depicted that it can be employed four times for the photocatalytic reactions with the same yield of CPS degradation. Besides, the CPS degradation efficiency at the optimum conditions was found to be 81.1% and 90.8% for the photo‐degradation and sonophotodegradation, respectively. Pursuant to the kinetic studies, the kinetics models that govern these processes are leaner with acceptable accuracy.
Conformational Space Sampled by Domain Reorientation of Linear Diubiquitin Reflected in Its Binding Mode for Target Proteins
Authors: Hou Xue‐Ni , Sekiyama Naotaka , Ohtani Yasuko , Yang Feng , Miyanoiri Yohei , Akagi Ken‐ichi , Su Xun‐Cheng , Tochio Hidehito
Published: April 2021

Linear polyubiquitin chains regulate diverse signaling proteins, in which the chains adopt various conformations to recognize different target proteins. Thus, the structural plasticity of the chains plays an important role in controlling the binding events. Herein, paramagnetic NMR spectroscopy is employed to explore the conformational space sampled by linear diubiquitin, a minimal unit of linear polyubiquitin, in its free state. Rigorous analysis of the data suggests that, regarding the relative positions of the ubiquitin units, particular regions of conformational space are preferentially sampled by the molecule. By combining these results with further data collected for charge‐reversal derivatives of linear diubiquitin, structural insights into the factors underlying the binding events of linear diubiquitin are obtained.
A Machine Learning Approach for Metal Oxide Based Polymer Composites as Charge Selective Layers in Perovskite Solar Cells
Authors: Yildirim Murat Onur , Gok Elif Ceren , Hemasiri Naveen Harindu , Eren Esin , Kazim Samrana , Oksuz Aysegul Uygun , Ahmad Shahzada
Published: May 2021

A library of metal oxide‐conjugated polymer composites was prepared, encompassing WO3‐polyaniline (PANI), WO3‐poly(N‐methylaniline) (PMANI), WO3‐poly(2‐fluoroaniline) (PFANI), WO3‐polythiophene (PTh), WO3‐polyfuran (PFu) and WO3‐poly(3,4‐ethylenedioxythiophene) (PEDOT) which were used as hole selective layers for perovskite solar cells (PSCs) fabrication. We adopted machine learning approaches to predict and compare PSCs performances with the developed WO3and its composites. For the evaluation of PSCs performance, a decision tree model that returns 0.9656 R2score is ideal for the WO3‐PEDOT composite, while a random forest model was found to be suitable for WO3‐PMANI, WO3‐PFANI, and WO3‐PFu with R2scores of 0.9976, 0.9968, and 0.9772 respectively. In the case of WO3, WO3‐PANI, and WO3‐PTh, a K‐Nearest Neighbors model was found suitable with R2scores of 0.9975, 0.9916, and 0.9969 respectively. Machine learning can be a pioneering prediction model for the PSCs performance and its validation.
Comprehensive Allele Genotyping in Critical Pharmacogenes Reduces Residual Clinical Risk in Diverse Populations
Authors: Luo Shishi , Jiang Ruomu , Grzymski Joseph J. , Lee William , Lu James T. , Washington Nicole L.
Published: April 2021

Genomic‐guided pharmaceutical prescribing is increasingly recognized as an important clinical application of genetics. Accurate genotyping of pharmacogenomic (PGx) genes can be difficult, owing to their complex genetic architecture involving combinations of single‐nucleotide polymorphisms and structural variation. Here, we introduce the Helix PGx database, an open‐source star allele, genotype, and resulting metabolic phenotype frequency database for CYP2C9, CYP2C19, CYP2D6, and CYP4F2, based on short‐read sequencing of >86,000 unrelated individuals enrolled in the Helix DNA Discovery Project. The database is annotated using a pipeline that is clinically validated against a broad range of alleles and designed to call CYP2D6 structural variants with high (98%) accuracy. We find that CYP2D6 has greater allelic diversity than the other genes, manifest in both a long tail of low‐frequency star alleles, as well as a disproportionate fraction (36%) of all novel predicted loss‐of‐function variants identified. Across genes, we observe that many rare alleles (<0.1% frequency) in the overall cohort have 10 times higher frequency in one or more subgroups with non‐European genetic ancestry. Extending these PGx genotypes to predicted metabolic phenotypes, we demonstrate that >90% of the cohort harbors a high‐risk variant in one of the four pharmacogenes. Based on the recorded prescriptions for >30,000 individuals in the Healthy Nevada Project, combined with predicted PGx metabolic phenotypes, we anticipate that standard‐of‐care screening of these 4 pharmacogenes could impact nearly half of the general population.
OH− Conductive Properties and Water Uptake of Anion Exchange Thin Films
Authors: Wang Fangfang , Wang Dongjin , Nagao Yuki
Published: April 2021

Several investigations have indicated that proton conduction and hydration properties of acidic ionomers differ from those of membranes. However, relations between the OH− conductivity and water uptake in thin film forms of anion exchange membranes have not been reported yet. For this study, new in situ measurements were established to elucidate the OH− conductivity and water uptake without allowing any influence of CO2 from the air. Poly[(9,9‐bis(6′‐(N,N,N‐trimethylammonium)‐hexyl)‐9H‐fluorene)‐alt‐(1,4‐benzene)], denoted as PFB+, was synthesized as a model ionomer. The highest OH− conductivity of 273 nm‐thick PFB+ film was 5.3×10−2 S cm−1 at 25 °C under 95 % relative humidity (RH), which is comparable to the reported OH− conductivity of PFB+ membrane. Reduced OH− conductivity was found in the thinner film at 95 % RH. The decreased OH− conductivity is explainable by the reduced number of water molecules contained in the thinner film. The OH− conductivity was reduced only slightly under the same water uptake.