bluuebunny/crossref_metadata_2025 huggingface dataset:
Nematic Ordering of Anisotropic Nanoparticles in Block Copolymers
Authors: Diaz Javier , Pinna Marco , Zvelindovsky Andrei V. , Pagonabarraga Ignacio
Published: December 2021

Block copolymer melts have been previously used to control the position and alignment of anisotropic nanoparticles. In this work, 2D and 3D mesoscopic simulations are used to explore the phase behavior of block copolymer/nanoparticle systems. The method combines a time‐dependent Ginzburg‐Landau for the polymer and Brownian dynamics for the anisotropic nanoparticles. Rhomboidal and spheroidal shaped particles are simulated in two and three dimensions, respectively. It is found that the nanoparticle nematic order aligned by the block copolymer domains enhances the lamellar phase of the block copolymer, due to an anisotropy‐driven phase transition. Additionally, anisotropic nanoparticles within circular‐forming block copolymer leads to a competition between the nematic colloidal ordering and the hexagonally ordered mesophase. At large concentrations, the nematic order dominates, deforming the block copolymer mesophase.
A Versatile Cation Additive Enabled Highly Reversible Zinc Metal Anode
Authors: Yao Rui , Qian Long , Sui Yiming , Zhao Guangyao , Guo Rongsheng , Hu Shengyu , Liu Peng , Zhu Haojie , Wang Fangcheng , Zhi Chunyi , Yang Cheng
Published: December 2021

Aqueous zinc metal batteries are receiving broad attention owing to their promising characteristics of low cost, high safety, and environmental benignity. However, severe side reactions over zinc metal anodes (i.e., dendrite growth and by‐product formation) dramatically limit their further development. Herein, the key problems are tackled by introducing a dual‐function electrolyte additive (ammonium cation‐based salts) to achieve long‐term and highly reversible zinc plating/stripping. Specifically, the cation can homogenize the zinc deposition via the charge shielding effect and inhibit by‐product formation by participating in the constitution of contact ion pairs. In such a way, the Zn||Zn symmetric cell stably cycles over 2145 h at a current density of 1 mA cm−2 with the overpotential of merely 25 mV. In addition, the reversibility of energy storage devices based on manganese dioxide and an activated carbon cathode is effectively enhanced. This strategy provides a promising approach for the future development of advanced aqueous metal batteries.
Unlocking Failure Mechanisms and Improvement of Practical Li–S Pouch Cells through In Operando Pressure Study
Authors: Chinnam Parameswara R. , Xu Leidong , Cai Lu , Cordes Nikolaus L. , Kim Sangwook , Efaw Corey M. , Murray Daniel J. , Dufek Eric J. , Xu Hongyi , Li Bin
Published: December 2021

For lithium–sulfur battery commercialization, research at a pouch cell level is essential, as some problems that can be ignored or deemed minimal at a smaller level can have a greater effect on the performance of the larger pouch cell. Herein, the failure mechanisms of Li–S pouch cells are deeply investigated via in operando pressure analysis. It is found that highly porous structures of cathodes/separators and slow electrolyte diffusion through cathodes/separators can both lead to poor initial wetting. Additionally, the Li‐metal anode dominates the thickness variation of the whole pouch cell, which is verified by in situ measured pressure variation. Consequently, a real‐time approach that combines normalized pressure with differential pressure analysis is proposed and validated to diagnose the morphology evolution of the Li‐metal anode. Moreover, applied pressure and porosity/tortuosity ratio of the cathode are both identified as independent factors that influence anode performance. In addition to stabilizing anodes, high pressure is proven to improve the cathode connectivity and avoid cathode cracking over cycling, which improves the possibility of developing cathodes with high sulfur mass loading. This work provides insights into Li–S pouch cell design (e.g., cathode and separator) and highlights pathways to improve cell capacity and cycling performance with applied and monitored pressure.
Color‐tunable and bright nonconjugated fluorescent polymer dots and fast photodegradation of dyes under visible light
Authors: Han Bingyan , Yan Qifang , Xin Ze , Liu Qingdong , Li Dan , Wang Jiao , He Gaohong
Published: December 2021

Nonconjugated polymer dots (PDs) without largely conjugated structures entitle their advantages such as environment friendliness, nontoxicity, and intrinsic fluorescence. However, color‐tunable PDs remain a challenge. Herein, polyvinyl pyrrolidone (PVP) and ascorbic acid (AA) are used to synthesize nonconjugated PDs, namely, PA PDs with intensive blue emission. The introduction of a third component, m‐phenylenediamine (MPD), redshifted the emission to green. The as‐prepared color‐tunable blue to green emissive PDs exhibit excellent properties, whether in solution or in solid state, originated from the mechanism of clustering‐triggered emission (CTE) induced by the overlap of electron‐rich atoms, the strong inter/intrachain interaction. The quantum yields of blue and green PDs reached up to 15.07% and 28.22%, respectively. Furthermore, PA PDs were successfully applied to the highly efficient photocatalytic degradation for dyes: methylene blue (MB) and methyl orange (MO) were degraded by 89.9% and 93.8% within 20 min under visible light, respectively.
Multistage nonlinear model predictive control for pumping treatment in hydraulic fracturing
Authors: Lin Kuan‐Han , Eason John P. , Biegler Lorenz T.
Published: December 2021

Hydraulic fracturing has gained increasing attention as it allows the constrained natural gas and crude oil to flow out of low‐permeability shale formations and significantly increase production. Perilous operating states of extremely high pressure also raise some safety concerns, requiring us to formulate an appropriate dynamic model, and provide a careful engineering control to ensure safe operating conditions. Moreover, uncertainties due to spatially varying rock properties increase the difficulties in control of the fracturing process. In this work, we formulate a first‐principles model by considering the fracture evolution, mass transport of substances in the slurry, changing fluid properties, and the monitored operating pressure on the ground level. Next, we implement nonlinear model predictive control (NMPC) to control the process under a set of final requirements and process constraints. Our results show that the performance of standard NMPC degrades when the rock uncertainty causes the parameter mismatch between the process and the predictive model in the controller. With standard NMPC, designed with a nominal model, the process fails to meet the terminal requirements of fracture geometry, and pressure is violated in one of the parameter mismatch cases. Therefore, we resort to multistage NMPC, which considers uncertainty evolution in a scenario tree with separate control sequences to address constraint violations. We demonstrate that multistage NMPC presents good performance by showing constraint satisfaction whether the uncertain rock parameter realization is time‐invariant or time‐variant. We also simulate the process with multistage NMPC including different numbers of scenarios and compare their control performance. Our investigation demonstrates that multistage NMPC effectively manages parametric uncertainties attributed to non‐homogeneous rock formation, and provides a promising control strategy for the hydraulic fracturing process.
A generalized reduced fluid dynamic model for flow fields and electrodes in redox flow batteries
Authors: Cheng Ziqiang , Tenny Kevin M. , Pizzolato Alberto , Forner‐Cuenca Antoni , Verda Vittorio , Chiang Yet‐Ming , Brushett Fikile R. , Behrou Reza
Published: December 2021

High‐dimensional models typically require a large computational overhead for multiphysics applications, which hamper their use for broad‐sweeping domain interrogation. Herein, we develop a modeling framework to capture the through‐plane fluid dynamic response of electrodes and flow fields in a redox flow cell, generating a computationally inexpensive two‐dimensional (2D) model. We leverage a depth‐averaging approach that also accounts for variations in out‐of‐plane fluid motion and departures from Darcy's law that arise from averaging across three‐dimensions (3D). Our resulting depth‐averaged 2D model successfully predicts the fluid dynamic response of arbitrary in‐plane flow field geometries, with discrepancies of <5% for both maximum velocity and pressure drop. This corresponds to reduced computational expense, as compared to 3D representations (<1% of duration and 10% of RAM usage), providing a platform to screen and optimize a diverse set of cell geometries.
Palladium‐Catalyzed Selective Hydroamination of Aliphatic Alkenes with Hydrazides
Authors: Xia Lanlan , Wu Yundan , Lin Cong , Gao Fei , Shen Liang
Published: December 2021

The first facile and efficient palladium‐catalyzed selective hydroamination of aliphatic alkenes with hydrazides as nitrogen‐based reaction partners has been described. This method provides a divergent and regioselective access to a variety of γ‐ and δ‐hydrazide substituted amide derivatives. The 8‐aminoquinolyl directing group could be readily removed to afford the corresponding γ‐ and δ‐hydrazide substituted carboxylic acid derivatives that are commonly seen in drug molecules and other bioactive compounds.
Spinal Cord Atrophy Predicts Progressive Disease in Relapsing Multiple Sclerosis
Authors: Bischof Antje , Papinutto Nico , Keshavan Anisha , Rajesh Anand , Kirkish Gina , Zhang Xinheng , Mallott Jacob M. , Asteggiano Carlo , Sacco Simone , Gundel Tristan J. , Zhao Chao , Stern William A. , Caverzasi Eduardo , Zhou Yifan , Gomez Refujia , Ragan Nicholas R. , Santaniello Adam , Zhu Alyssa H. , Juwono Jeremy , Bevan Carolyn J. , Bove Riley M. , Crabtree Elizabeth , Gelfand Jeffrey M. , Goodin Douglas S. , Graves Jennifer S. , Green Ari J. , Oksenberg Jorge R. , Waubant Emmanuelle , Wilson Michael R. , Zamvil Scott S. ,   University of California, San Francisco MS‐EPIC Team, Cree Bruce A. C. , Hauser Stephen L. , Henry Roland G.
Published: December 2021

Objective

A major challenge in multiple sclerosis (MS) research is the understanding of silent progression and Progressive MS. Using a novel method to accurately capture upper cervical cord area from legacy brain MRI scans we aimed to study the role of spinal cord and brain atrophy for silent progression and conversion to secondary progressive disease (SPMS).

Methods

From a single‐center observational study, all RRMS (n = 360) and SPMS (n = 47) patients and 80 matched controls were evaluated. RRMS patient subsets who converted to SPMS (n = 54) or silently progressed (n = 159), respectively, during the 12‐year observation period were compared to clinically matched RRMS patients remaining RRMS (n = 54) or stable (n = 147), respectively. From brain MRI, we assessed the value of brain and spinal cord measures to predict silent progression and SPMS conversion.

Results

Patients who developed SPMS showed faster cord atrophy rates (−2.19%/yr) at least 4 years before conversion compared to their RRMS matches (−0.88%/yr, p < 0.001). Spinal cord atrophy rates decelerated after conversion (−1.63%/yr, p = 0.010) towards those of SPMS patients from study entry (−1.04%). Each 1% faster spinal cord atrophy rate was associated with 69% (p < 0.0001) and 53% (p < 0.0001) shorter time to silent progression and SPMS conversion, respectively.

Interpretation

Silent progression and conversion to secondary progressive disease are predominantly related to cervical cord atrophy. This atrophy is often present from the earliest disease stages and predicts the speed of silent progression and conversion to Progressive MS. Diagnosis of SPMS is rather a late recognition of this neurodegenerative process than a distinct disease phase. ANN NEUROL 2022;91:268–281
Insular Stimulation Produces Mental Clarity and Bliss
Authors: Nencha Umberto , Spinelli Laurent , Vulliemoz Serge , Seeck Margitta , Picard Fabienne
Published: December 2021

For the first time, an ecstatic aura has been evoked through the electrical stimulation of the dorsal anterior insula during presurgical invasive intracerebral monitoring in a patient who did not suffer from an ecstatic form of epilepsy. This case provides more evidence that the anterior insula is the major generator of such a mystical‐type experience even in individuals with no underlying brain network changes related to a preexisting ecstatic epilepsy. ANN NEUROL 2022;91:289–292
Cathespin B‐Initiated Cypate Nanoparticle Formation for Tumor Photoacoustic Imaging
Authors: Wang Chenchen , Du Wei , Wu Chenfan , Dan Shan , Sun Miao , Zhang Tong , Wang Bin , Yuan Yue , Liang Gaolin
Published: December 2021

Cathepsin B (CTSB) is a lysosomal protease that is overexpressed in the early stage of many cancer types. Precise evaluation of CTSB expression in vivo may provide a promising method for the early diagnosis of cancers. By virtue of the high‐resolution PA imaging modality, a “smart” photoacoustic (PA) probe Cypate‐CBT, which can self‐assemble to cypate‐containing nanoparticles in response to abundant GSH and CTSB inside tumor cells, was developed for the sensitive and specific detection of CTSB activity. Compared with unmodified Cypate, our probe Cypate‐CBT exhibited a 4.9‐fold or 4.7‐fold PA signal enhancement in CTSB‐overexpressing MDA‐MB‐231 cancer cells or tumors, respectively, revealing intracellular accumulation of the probe after CTSB‐initiated self‐assembly. We expect Cypate‐CBT to be employed as an effective PA imaging agent for clinical diagnosis of cancer at early stages.
Electrochemical Desaturative β‐Acylation of Cyclic N‐Aryl Amines
Authors: Feng Tian , Wang Siyi , Liu Yin , Liu Shouzhuo , Qiu Youai
Published: December 2021

Herein, we disclose a straightforward, robust, and simple route to access β‐substituted desaturated cyclic amines via an electrochemically driven desaturative β‐functionalization of cyclic amines. This transformation is based on multiple single‐electron oxidation processes using catalytic amounts of ferrocene. The reaction proceeds in the absence of stoichiometric amounts of electrolyte under mild conditions, affording the desired products with high chemo‐ and regioselectivity. The reaction was tolerant of a broad range of substrates and also enables late‐stage β‐C(sp3)−H acylation of potentially valuable products. Preliminary mechanistic studies using cyclic voltammetry reveal the key role of ferrocene as a redox mediator in the reaction.
Flame retardancy of polyurethane foams prepared from green polyols with flame retardants
Authors: Lee Pyung Soo , Jung Simon MoonGeun
Published: December 2021

Polyurethane foams (PUFs) were synthesized using bis(2‐hydroxyethylene terephthalate) (BHET), 1,4‐cyclohexanedimethanol (CHDM), and polycaprolactone diol (PCLD), and their flame retardancies were investigated. BHET and CHDM are eco‐friendly chemicals derived from waste polyethylene terephthalate, and PCLD is a precursor monomer used for synthesizing biodegradable polymers. Expandable graphite (EG) and tris(1‐chloro‐2‐isopropyl) phosphate (TCPP) were used as flame retardants. For conventional PUFs prepared with an aliphatic polyol, thermal stability was significantly enhanced with EG and TCPP through thermogravimetric analysis (TGA) and micro‐combustion calorimetry (MCC). PUFs prepared with BHET and CHDM exhibited higher thermal stability than conventional PUFs. This is attributed to the alicyclic and aromatic ring structures, which contribute to thermally stable char formation during pyrolysis. PCLD was introduced as an additional polyol, as well as a possible flame retardant, without the addition of EG and TCPP. PUFs were successfully prepared and exhibited improved resilience to burning up to 300°C due to the intrinsic thermal stability of PCLD. The limiting oxygen index (LOI) indicated that PUFs containing BHET moiety exhibited higher LOI values, whereas PUFs prepared with PCLD showed the lowest LOI value. PCLD can be used as a polyol; however, additional flame retardants are needed to obtain high flame retardancy for PUFs.
Preparation and characterization of citric acid crosslinked chitosan‐cellulose nanofibrils composite films for packaging applications
Authors: Ponnusamy Prabaharan Graceraj , Sundaram Jaya , Mani Sudhagar
Published: December 2021

The inferior water vapor permeability and water resistance properties are the major challenges that hindered the development of chitosan‐CNF composites for packaging applications. In this study, the chitosan‐CNF composite films were prepared with in situ crosslinking of citric acid (CA) to reduce the percent water uptake (WU) and water vapor permeability (WVP). The composite films were produced by the solvent casting method with 10%, 15%, and 20% CNF as a reinforcement, 20%, 25%, and 30% CA as a crosslinker, and 20% glycerol as a plasticizer. The Fourier transform infrared (FTIR) spectra of composite films with a peak at 1710 cm−1 confirmed the effective crosslinking of citric acid on the chitosan‐CNF matrix. The crosslinked composite films exhibited the lowest WU of 39% and WVP of 9.99 × 10−7 g/Pa s m2 with reduced light transmittance due to CNF reinforcement. The scanning electron microscopy (SEM) study showed the smooth surface morphology of composite films. The CA crosslinking slightly decreased the tensile strength of composite films. However, the composite film with optimal CNF and CA concentration (25% and 20%, respectively) exhibited comparable tensile strength with other synthetic and biopolymer composites and can be used as a potential biopolymer composite for packaging applications.
Finteching remittances in paradise: A path to sustainable development
Authors: Hahm Hongjoo , Subhanij Tientip , Almeida Rui
Published: December 2021

The costs of sending remittances to Pacific small island developing states (SIDS) are among the highest in the world. Tackling this issue is crucial not only for economic and social development, but also for improving financial inclusion. This article analyses fintech adoption in remittance services, namely the adoption of alternative payment methods in transferring money by using the internet or mobile phones, in the Pacific. It introduces an original framework to assess the current landscape of fintech in the remittance sector and draws tailored policy recommendations. The framework is conceptualised through a ladder with five rungs: availability, accessibility, awareness, literacy and trust. Based on the ladder analysis, the authors observe the lack of basic digital infrastructure and digital platforms in many Pacific SIDS. Where the technological landscape is better developed, fintech services have established strong footholds, but there is a need for greater awareness to broaden its appeal and customer base. The benefits of fintech platforms are high, especially in the context of lower remittance costs which constitute an unduly large share of GDP in Pacific SIDS. The basic infrastructure needed to develop fintech services are equally important for the overall sustainable development of Pacific SIDS. The article observes fintech services in the Pacific are a means for financial inclusion of the unbanked, that can accelerate the economic and social development of the SIDS, and countries in the Pacific region are at different stages in their readiness for fintech adoption.
Haemolymph metabolomic differences in silkworms (Bombyx mori L.) under mulberry leaf and two artificial diet rearing methods
Authors: Tao Shanshan , Wang Jie , Liu Minghui , Sun Fan , Li Bing , Ye Chongjun
Published: December 2021

The new technology of silkworm (Bombyx mori L.) artificial feed breeding has many characteristics and advantages. This study assessed silkworm rearing with mulberry leaf at all instars (MF) as the control, and used metabolomics to explore the differences in haemolymph metabolism of fifth instar silkworms under two modes of rearing with an artificial diet at all instars (AF) and rearing with an artificial diet during first to third instars and mulberry leaf during the fourth and fifth instars (AMF). The results show that, compared with silkworms of the MF group, the amount and fold change of various metabolites were higher in the haemolymph of AF group silkworms, and the metabolism of amino acids and uric acid, carbohydrates, lipids, and vitamins were changed. These changes may be the reasons for the poor performance of the AF silkworms. However, the amount and fold change of the various metabolites of silkworms in the AMF group were lower, and some metabolic pathways were more active. The amount of material and energy supply were greater. These changes could explain the high efficiency growth of body weight of silkworms after the conversion from artificial diet rearing to mulberry leaf rearing. These findings provide an important theoretical basis for the optimisation of artificial diet rearing technology for silkworms.
A chalcone‐based fluorescent chemosensor for detecting Mg2+ and Cd2+
Authors: Park Soyoung , Suh Boeon , Kim Cheal
Published: December 2021

SBOD (sodium (E)‐2‐(3‐[5‐bromothiophen‐2‐yl]‐3‐oxoprop‐1‐en‐1‐yl)‐4,6‐dichlorophenolate) was designed and synthesized as a chalcone‐based fluorescent turn‐on chemosensor for Mg2+ and Cd2+. SBOD selectively detected Mg2+ and Cd2+ through the increase in effective fluorescence. Detection limits of SBOD for Mg2+ and Cd2+ were calculated to be 3.8 μM and 2.9 μM, respectively. The binding modes of SBOD for Mg2+ and Cd2+ were determined to be 1:1 by ESI‐MS and Job plot. Association mechanisms for SBOD to Mg2+ and Cd2+ were illustrated by ESI‐MS, UV–vis, fluorescence spectroscopy, and calculations.
Prediction of human cytochromeP450inhibition using bio‐selectivity induced deep neural network
Authors: Park Hyejin , Brahma Rahul , Shin Jae‐Min , Cho Kwang‐Hwi
Published: December 2021

Since the successful debut of AlphaGo, deep learning (DL) techniques have been applied to almost all areas of data sciences and are achieving remarkable milestones. For example, in predicting cytochrome P450 (CYP450) inhibition, DL and other machine learning techniques applied were proven significantly useful. However, currently, most models are focused on how much they can improve compared to previously published methods by using different methodologies and larger data sets without considering bio‐selectivity. This study provides a multitask classification model for five important isoforms of CYP450. Our model uses the most extensive data set of over 150 000 molecules ever used. To consider the stereoisomerism of bio‐selectivity, new descriptors have been developed. We illustrated the discriminating power of the new descriptors with some examples that demonstrated the improvement in the model's performance using three‐dimensional descriptors, which account for the stereoselectivity of drug–protein/enzymes that two‐dimensional models cannot achieve.
Synthesis of catechol‐conjugated chitosan and its application as an additive for cement mortar
Authors: Choi Hoe Young , Bae Sung‐Ho , Choi Se‐Jin , Ko Haye Min
Published: December 2021

We synthesized catechol‐conjugated chitosan (CCC) to study its usefulness as a construction material additive in cement mortar. The degree of catechol conjugation (DOCcat) of the synthesized CCC was determined to be approximately 14% by UV–vis and 1H NMR spectroscopy. Furthermore, the hydroxyl and amine groups in CCC could play a crucial role in hydrogen bonding, metal coordination, and cross‐linking processes via interaction with adducts from cement mortar. In this study, we observed an improvement in the compressive strength and absorption rate, suggesting that CCC is a promising candidate for high‐performance cement mortar.
Utilisation of CO2 as “Structure Modifier” of Inorganic Solids
Authors: Bennett M. J. , Dobson I. , Benoit D. M. , Francesconi M. G.
Published: December 2021

Utilisation of CO2 as a chemical reagent is challenging, due to the molecule's inherent chemical stability. However, CO2 reacts promptly at high temperature (∼1000 °C) with alkaline‐earth oxides to form carbonates and such reactions are used towards capture and re‐utilisation. In this work, this concept is extended and CO2 is utilised as a reagent to modify the crystal structure of mixed‐metal inorganic solids. Modification of the crystal structure is a “tool” used by materials scientists to tailor the physical property of solids. CO2 gas was reacted with several isostructural mixed‐metal oxides Sr2CuO3, Sr1.8Ba0.2CuO3 and Ba2PdO3. These oxides are carefully selected to show anion vacancies in their crystal structure, to act as host sites for CO2 molecules, leading to the formation of carbonate anions, (CO3)2−. The corresponding oxide carbonates were formed successfully and the favourable formation of SrCO3 as secondary phase was minimised via an innovative, yet simple synthetic procedure involving alternating of CO2 and air. We also derived a simple model to predict the kinetics of the reactions for the cuprates, using first‐principles density functional theory and assimilating the reaction to a gas‐surface process.
Alkaline Stability of Low Oxophilicity Metallopolymer Anion‐Exchange Membranes
Authors: Aggarwal Kanika , Bsoul Saja , Douglin John C. , Li Songlin , Dekel Dario R. , Diesendruck Charles E.
Published: December 2021

Anion‐exchange membrane fuel cells (AEMFCs) are promising energy conversion devices due to their high efficiency. Nonetheless, AEMFC operation time is currently limited by the low chemical stability of their polymeric anion‐exchange membranes. In recent years, metallopolymers, where the metal centers assume the ion transport function, have been proposed as a chemically stable alternative. Here we present a systematic study using a polymer backbone with side‐chain N‐heterocyclic carbene (NHC) ligands complexed to various metals with low oxophilicity, such as copper, zinc, nickel, and gold. The golden metallopolymer, using the metal with the lowest oxophilicity, demonstrates exceptional alkaline stability, far superior to state‐of‐the‐art quaternary ammonium cations, as well as good in situ AEMFC results. These results demonstrate that judiciously designed metallopolymers may be superior to purely organic membranes and provides a scientific base for further developments in the field.
Promoter‐Driven Overexpression in Chromobacterium vaccinii Facilitates Access to FR900359 and Yields Novel Low Abundance Analogs
Authors: Pistorius Dominik , Buntin Kathrin , Weber Eric , Richard Etienne , Bouquet Caroline , Wollbrett Séverine , Regenass Hugo , Peón Victor , Böhm Marcel , Kessler Régis , Gempeler Thomas , Haberkorn Anne , Wimmer Laurin , Lanshoeft Christian , Davis John , Hainzl Dominik , D'Alessio Joseph Anthony , Manchado Eusebio , Petersen Frank
Published: December 2021

Access to the cyclic depsipeptide FR900359 (FR), a selective Gq/11 protein inhibitor of high pharmacological interest and a potential lead molecule for targeted therapy of cancers with oncogenic GNAQ or GNA11 mutations (encoding Gq and G11 respectively), has been challenging ever since its initial discovery more than three decades ago. The recent discovery of Chromobacterium vaccinii as a cultivable FR producer enables the development of approaches leading to a high‐yielding, scalable and sustainable biotechnological process for production of FR, thereby removing this bottleneck. Here we characterize different promoters in exchange of the native promoter of the FR assembly line, resulting in an overexpression mutant with significantly increased production of FR. Thereby, the isolation and structure elucidation of novel FR analogs of low abundance is enabled. Further, we explore the antiproliferative activities of fifteen chromodepsins against uveal melanoma cell lines harboring Gq/11 mutations and characterize the major metabolite of FR formed in plasma.
BBr3‐Mediated P(III)‐Directed C−H Borylation of Phosphines
Authors: Lv Jiahang , Zhang Xue‐Jun , Wang Minyan , Zhao Yue , Shi Zhuangzhi
Published: December 2021

Transition‐metal‐catalyzed C−H borylation has been widely used in the preparation of organoboron compounds. Here, we developed a general protocol on metal‐free P(III)‐directed C−H borylation of phosphines mediated by BBr3, resulting in the formation of products bearing both phosphorus and boron. The development of the metal‐free strategy to mimic previous metallic processes has shown low cost, superior practicality, and environmental friendliness. Density functional theory (DFT) calculations demonstrate the preferred pathway for this metal‐free directed C−H borylation process.
Rhodium and Iridium Complexes of Anionic Thione and Selone Ligands Derived from Anionic N‐Heterocyclic Carbenes
Authors: Ho Luong Phong , Neitzel Angelika , Bannenberg Thomas , Tamm Matthias
Published: December 2021

The lithium salts of anionic N‐heterocyclic thiones and selones [{(WCA‐IDipp)E}Li(toluene)] (1: E=S; 2: E=Se; WCA=B(C6F5)3, IDipp=1,3‐bis(2,6‐diisopropylphenyl)imidazolin‐2‐ylidene), which contain a weakly coordinating anionic (WCA) borate moiety in the imidazole backbone were reacted with Me3SiCl, to furnish the silylated adducts (WCA‐IDipp)ESiMe3 (3: E=S; 4: E=Se). The reaction of the latter with [(η5‐C5Me5)MCl2]2 (M=Rh, Ir) afforded the rhodium(III) and iridium(III) half‐sandwich complexes [{(WCA‐IDipp)E}MCl(η5‐C5Me5)] (5–8). The direct reaction of the lithium salts 1 and 2 with a half or a full equivalent of [M(COD)Cl]2 (M=Rh, Ir) afforded the monometallic complexes [{(WCA‐IDipp)E}M(COD)] (9–12) or the bimetallic complexes [μ2‐{(WCA‐IDipp)E}M2(COD)2(μ2‐Cl)] (13–16), respectively. The bonding situation in these complexes has been investigated by means of density functional theory (DFT) calculations, revealing thiolate or selenolate ligand character with negligible metal‐chalcogen π‐interaction.
Proton Conductivity of Porous Zirconium‐Organic Frameworks Filled with Protic Ionic Liquid
Authors: Seidler Christopher F. , Wark Michael
Published: December 2021

Infiltration of the protic ionic liquid (PIL) triethylammmonium trifluoromethanesulfonate (TEA‐TFA) into the pores of zirconium metal organic‐frameworks (Zr‐MOFs) featuring interpenetrated networks, so‐called PIZOFs, leads to highly proton conducting dry solids. In case of PIZOFs their modular synthesis allows tailoring the environment in the pores via the chemical nature of the side chains at the organic linkers. By infiltration of different PIZOFs with 50 wt % of the PIL, nanocomposites exhibiting high proton conductivity under anhydrous conditions were obtained. The proton conductivity strongly depends on the chemical nature of the PIZOF pores, i.e., the kind of side chains at the linkers. Gas adsorption studies show that the side chains strongly influence the porosity and the hydrophilicity of the PIZOF materials.
Facile Preparation of Chitosan‐modified Mesoporous Titanium Dioxide Film on Fused‐silica Capillary for Selective Enrichment of Phosphopeptides
Authors: Lv Xinyan , Jiao Shihui , Cui Lili , Wei Zhonglin , Wang Boran , Wang Wenwen , Zhang Qi , Tan Yumei , Pang Guangsheng , Feng Shouhua
Published: December 2021

Chitosan (Cts), a positively charged natural polysaccharide, is employed to functionalize mesoporous titanium dioxide (mTiO2) nanoparticles. The prepared Cts/mTiO2 composite was used as a stationary phase to coat the inner wall of fused‐silica capillary and obtain uniform Cts/mTiO2 film. The Cts/mTiO2 film is applied to detect and enrich phosphopeptides in complex biological samples based on typical in‐tube solid phase microextraction (IT‐SPME) system. This unique Cts/mTiO2 film exhibits excellent enrichment performances of high selectivity (β‐casein and BSA in molar ratio of 1 : 1000), sensitivity (detection limit as low as 40 fmol of β‐casein tryptic digest solution) and high adsorption capacity (124.5 μg mg−1). Meanwhile, the Cts/mTiO2 film possesses preferable reusability and can be reused more than 10 times. These results confirm that the Cts/mTiO2 film possesses potential and satisfactory prospects in phosphoproteomics analysis.
Synthesis of 6‐Aza‐2‐Hydroxyimino‐5‐Methylpyrimidine Nucleosides for Antiviral Evaluation
Authors: Abou‐Elkhair Reham A. I , Du Jinxi , Wasfy Abdalla A. , Khaill Nisrin A. , Maaroof Hend M. , Hassan Marwa H. , Ahmed Ayman S. , Hassan Abdalla E. A. , Sheng Jia
Published: December 2021

The syntheses of a series of novel 6‐aza‐2‐hydroxyimino‐5‐methylpyrimidine and related nucleosides are described. A suitably protected 2‐methylthiopyrimidine nucleoside was selected as the precursor for installing a hydroxyimino moiety at the C‐2 position. The starting nucleobase 6‐aza‐5‐methyl‐2‐thiouracil is prepared in two steps from thiosemicarbazone and ethyl pyruvate. This is subjected to coupling with 1‐O‐acetyl‐2,3,5‐tri‐O‐benzoyl‐β‐D‐ribofuranose under Vorbrüggen glycosylation conditions to provide the corresponding nucleoside in high yield. Activation of the nucleoside to the corresponding 2‐methylthio derivative followed by treatment with hydroxylamine hydrochloride in pyridine provides the corresponding 2‐hydroxyimino derivative in high yield. Finally, the synthesis of five free modified nucleoside analogs is described. The newly synthesized nucleosides have been evaluated against an RNA viral panel and moderate activity was observed against hepatitis C virus, Zika virus, and human respiratory syncytial virus. © 2021 Wiley Periodicals LLC.

Basic Protocol 1: Preparation of 6‐aza‐5‐methyl‐2‐thiouracil

Basic Protocol 2: Preparation of 6‐aza‐5‐methyl‐2‐thiouridine and 6‐aza‐5‐methyluridine

Basic Protocol 3: Preparation of 6‐aza‐2‐hydroxyimino‐5‐methyluridine

Basic Protocol 4: Preparation of 6‐aza‐2‐hydroxyimino‐5‐methyl‐4‐thiouridine and 6‐aza‐2‐hydroxyimino‐5‐methylcytosine
Hybrid islanding detection technique for distribution network considering the dynamic behavior of power and load
Authors: Jhuma Umme Kulsum , Mekhilef Saad , Mubin Marizan , Ahmad Shameem , Rawa Muhyaddin , Alturki Yusuf
Published: December 2021

Nowadays, distributed generation (DG) has become an indispensable part for meeting the growing power demand in electrical power generation and distribution. However, one of the drawbacks of DG is unintentional islanding phenomena, which has become a safety issue for both human and equipment connected to the system. To prevent this hazardous condition, according to IEEE 1547 standards, this islanding condition must be detected within 2 s. This paper proposed an approach to develop a hybrid islanding detection method (IDM) to prevent the damages caused by this islanding condition. The proposed hybrid IDM is a combination of three different IDMs, two passive and one active; that is, rate of change of active power (ROCOAP) and rate of change of reactive power (ROCORP) are passive IDMs where load connecting strategy (LCS) is active. To differentiate islanding conditions with similar occurrences, different case studies are taken into account with photovoltaic (PV) and synchronous generator (SG) working as distributed generators on PSCAD/EMTDC platform. The simulation results confirm that proposed IDM is more favorable compared to other IDMs due to simplicity and fast islanding detection time when its performance is tested on the 11‐kV Malaysian distribution system for various cases.
Negative affect and binge eating: Assessing the unique trajectories of negative affect before and after binge‐eating episodes across eating disorder diagnostic classifications
Authors: Wonderlich Joseph A. , Crosby Ross D. , Engel Scott G. , Crow Scott J. , Peterson Carol B. , Le Grange Daniel , Wonderlich Stephen A. , Fischer Sarah
Published: December 2021

Objective

Ecological momentary assessment (EMA) studies suggest that among individuals who binge eat, emotional states and binge eating are functionally related. However, it is unclear whether the trajectory of negative affect (NA) is the same across diagnostic groups or if specific changes in affect are unique to each diagnostic category. This study examined the moderating effect of diagnosis on the trajectory of negative affect before and after binge eating.

Method

Adults with eating disorder diagnoses (anorexia nervosa [AN] = 118, bulimia nervosa [BN] = 133, binge‐eating disorder [BED] = 112) completed an EMA where they reported binge eating and negative affect throughout the day. Generalized estimating equation analyses were used to model the trajectories of NA before and after binge eating.

Results

For all individuals, the linear trajectory of NA significantly increased before (B = 0.044, p < .001) and decreased following the binge‐eating episode (B = −0.054, p < .001). However, diagnosis moderated this trajectory. Specifically, individuals with BN had a greater change in linear trajectories of NA before (B = 2.305, p < .001) and after (B = −4.149, p < .001) binge eating compared to those with BED, but not those with AN. There were no differences in the trajectory of NA between individuals with BED or AN.

Discussion

These findings suggest that binge‐eating episodes in BN may be more strongly associated with NA than in BED, but similar to binge‐eating episodes in AN.
Dancing on the platform: Lability of floral organs of Beilschmiedia appendiculata (Lauraceae)
Authors: Zeng Gang , Liu Bing , Ferguson David K. , Yang Yong
Published: December 2021

Floral characters are important for the systematics of the Lauraceae. However, structure and development of the flowers remain poorly known in the family. In this study, we observed the variation and early development of flowers of Beilschmiedia appendiculata, which belongs to the Cryptocarya clade of the family. The results indicate that the shoot apical meristems (SAMs) of the floral buds are enlarged and become a platform for the programmed initiation of the floral organs; floral organs develop basically in an acropetal pattern; phyllotaxis is whorled, initiation of floral primordia within a whorl is asynchronous; floral merosity is extremely variable, for example, dimerous, trimerous, tetramerous, dimerous plus trimerous, and trimerous plus tetramerous. In addition, this species has lost the innermost staminal whorl and glands are not closely associated with stamens of the third staminal whorl, which is unusual in the family Lauraceae. Our new observations broaden our knowledge of the variation of floral structure in Beilschmiedia and pose a fundamental question regarding the ecology underlying the lability of floral organs in B. appendiculata.
Molten Salt‐Shielded Synthesis (MS3) of MXenes in Air
Authors: Chen Jinjin , Jin Qianqian , Li Youbing , Shao Hui , Liu Pengcheng , Liu Ying , Taberna Pierre‐Louis , Huang Qing , Lin Zifeng , Simon Patrice
Published: December 2021

MXenes are two‐dimensional transition metal carbides and/or nitrides with unique physiochemical properties and have attracted extensive interest in numerous fields. However, current MXene synthesis methods are limited by hazardous synthesis conditions, high production costs, or difficulty in large‐scale production. Therefore, a general, safe, cost‐effective, and scalable synthesis method for MXenes is crucial. Here, we report the fast synthesis of MXenes in the open air using a molten salt‐shielded synthesis (MS3) method, which uses Lewis‐acid salts as etchants and a low‐melting‐point eutectic salt mixture as the reaction medium and shield to prevent MXene oxidation at high temperatures. Carbide and nitride MXenes, including Ti3C2Tx, Ti2CTx, Ti3CNTx, and Ti4N3Tx, were successfully synthesized using the MS3 method. We also present the flexibility of the MS3 method by scaling the etching process to large batches of 20 and 60 g of Ti3AlC2 MAX precursor in one pot. When used as negative electrodes, the prepared MS3‐MXenes delivered excellent electrochemical properties for high‐rate Li‐ion storage.
Highly Semitransparent Indoor Nonfullerene Organic Solar Cells Based on Benzodithiophene‐Bridged Porphyrin Dimers
Authors: Piradi Venkatesh , Xu Xiaopeng , Yin Hang , Ho Johnny Ka Wai , Yan Feng , Peng Qiang , So Shu Kong , Zhu Xunjin
Published: December 2021

Two acceptor‐donor‐acceptor‐based porphyrin dimers, C8TEBDT‐2P and C8TBDT‐2P, are presented as donors for high‐performance semitransparent indoor organic photovoltaics. Both compounds vary in that benzodithiophene (BDT) bridged the two porphyrins at the meso‐carbon directly for the latter with a less planar structure, and via ethynylene for the former with a more planar structure. As a result, the C8TEBDT‐2P exhibits a more red‐shifted absorption profile from 400 to 800 nm than the C8TBDT‐2P from 400 to 700 nm due to stronger π‐conjugation. Using indaceno‐dithiophene‐indene‐dimalononitrile (IDIC) as a nonfullerene acceptor, the blend film C8TEBDT‐2P:IDIC shows a promising power conversion efficiency (PCE) of 12.3% under indoor (300 lux light‐emitting diode) and a PCE of 7.46% under one sun illuminations. The improved efficiency of the device C8TEBDT‐2P: IDIC is mainly due to highly ordered surface morphology, that leads in efficient charge separation, faster charge transport, and less charge recombination. Furthermore, the photopic properties indicate that both devices have good transparency and chromaticity, with an average visible transmittance value of 70% for C8TEBDT‐2P:IDIC and 73% for C8TBDT‐2P:IDIC. This study enriches the pool of porphyrin donors for highly semi‐transparent indoor nonfullerene organic solar.
Maturity selection but not sowing date enhances soybean productivity and land use in a winter camelina–soybean relay system
Authors: Mohammed Yesuf Assen , Gesch Russ W. , Matthees Heather L. , Wells Samantha S.
Published: December 2021

Enhancing crop diversification is needed to ensure sustainable food and energy production in the soybean [Glycine max (L.) Merr.] and maize (Zea mays L.) dominated cropping systems of the US Midwest. Relay‐cropping soybean with winter camelina [Camelina sativa (L.) Crantz] is a means to sustainably intensify food and energy production while adding cropping system diversity. However, soybean yields in relay systems tend to be less than a full‐season monocrop. We hypothesized that improved soybean selection and seeding date for relay cropping could minimize this yield gap, thus increasing agricultural land use productivity. A 2‐year field study was conducted to determine the effects of soybean maturity and seeding date (SD) on winter camelina and soybean yields and land use productivity. Three soybean genotypes differing in maturity (MG) were relayed into winter camelina at rosette (SD1), bolting (SD2), and first flowering (SD3) growth stages. The soybean MGs were MG0.2, MG1.1, and MG1.7 representing early, standard, and late maturity, respectively, for the study region. The MG1.1 sown at SD2 was grown as sole crop check using conventional practices (CP). Results demonstrated that SD3 decreased camelina seed yield compared with SD1 and SD2. Soybean yield in the relay system was greatest for the MG1.7 genotype, and averaged across SD1 and SD2, was just 11.6% less than the sole crop CP check. Relaying soybean MG1.7 at SD2 produced 43% greater total (camelina +soybean) oil yield and greatly improved land use efficiency compared with CP. Appropriate soybean genotype selection can enhance winter camelina–soybean relay system productivity and land use efficiency.
Financially constrained index futures arbitrage
Authors: Glover Kristoffer , Hulley Hardy
Published: December 2021

We develop two models for index futures arbitrage that take the financing constraints faced by real‐world arbitrageurs into account. Our models predict that the price of an index futures contract and the value of its underlying index should deviate further from their theoretical cost‐of‐carry relationship when (a) the contract has a long time to go before expiry, and (b) volatility is high. The fact that these predictions enjoy considerable empirical support highlights the importance of financing constraints for explaining index futures mispricing.
Volatility model applications in China's SSE50 options market
Authors: Chi Yeguang , Hao Wenyan , Zhang Yifei
Published: December 2021

We investigate the effectiveness of various volatility models using China's Shanghai Stock Exchange‐50 (SSE50) Index. Regarding in‐sample fit, the generalized autoregressive conditional heteroscedasticity (GARCH) and the variants of the GARCH model perform much better than the autoregressive conditional heteroscedasticity model. However, we do not observe any significant asymmetric volatility response to past returns in the GJR–GARCH model. For out‐of‐sample forecasting of the future realized volatility, in five of the seven options we investigate, the GARCH volatility forecast outperforms the option implied volatility. We formulate a trading strategy by exploiting the spread between the GARCH volatility forecast and the option implied volatility, and show robust profits when applied to the SSE50 options.
Role of Co species on Co/KIT‐6 catalyst surface in CO2 hydrogenation
Authors: Zhou Guilin , Ai Xing , Tian Yunqi , Huang Rui , Feng Yongcheng , Ren Jianmin
Published: December 2021

Supported Co/KIT‐6 catalyst, which has high specific surface area and well‐developed ordered mesoporous structure, was prepared by wet impregnation method. Its physicochemical properties were characterized by transmission electron microscopy (TEM), Brunner–Emmet–Teller (BET), Low‐angle XRD, in situ X‐ray photoelectron spectroscopy (in situ XPS) and H2‐temperature program reduction (H2‐TPR), and its catalytic properties were investigated by CO2 hydrogenation. The in situ XPS and H2‐TPR results indicated that Co oxide species could be reduced by H2 to highly dispersed active metal Co species. The highly dispersed active metal Co species are the main CO2 hydrogenation active centers. CO2 molecules could be reduced by active metal Co species to generate CO molecules and promote CO2 methanation. The prepared Co catalyst presented high CO2 catalytic hydrogenation activities and stability. The CO2 conversion exceeds 47%, and CO and CH4 selectivity reaches 25.6% and 74.4% at 400°C within the range of reaction time of 500 min, respectively. © 2021 Society of Chemical Industry and John Wiley & Sons, Ltd.
A hybrid method combining membrane separation and chemical absorption for flexible CH4refinement and CO2separation in natural gas
Authors: Liu Jian , Kong Chengdong , Zhang Zhongxiao , Yang Liu
Published: December 2021

CO2removal is imperative in the sweetening of natural gas. In this work, a hybrid method combining membrane separation and chemical absorption is proposed and applied to test its performances in CH4refinement and CO2separation from natural gas. Specifically, the permeate stream from the membrane separation part was fed into the chemical absorption column. The retentate stream and the chemically scrubbed permeate stream were mixed to produce the final sweetened CH4. Parametric analysis indicates that the enriched CH4volume fraction increases with the growth of feed pressure, but it decreases as the gas flow rate increases. The CO2removal efficiency gets enhanced with the increment of feed pressure, gas temperature and monoethanolamine (MEA) concentration. Under an optimized condition with a feed pressure of 0.9 MPa, a gas flow rate of 40 L/min, a gas temperature of 45°C, a MEA concentration of 15%, and a MEA flow rate of 20 L/h, the high CH4volume fraction of 96.8%, 100% CH4recovery efficiency, and 80.4% CO2removal efficiency can be simultaneously achieved using the hybrid method. Compared with the membrane separation method, the hybrid method has higher CH4recovery efficiency and higher CH4volume fraction, which can meet the requirements of carbon capture utilization and storage (CCUS). Compared with the chemical absorption, the hybrid method consumes less MEA since a part of CO2can be separated by membrane separation. Therefore, the hybrid method is a promising technique for flexible CH4refinement and CO2separation in natural gas. © 2021 Society of Chemical Industry and John Wiley & Sons, Ltd.