bluuebunny/crossref_metadata_2025 huggingface dataset:
Use of Ferritin Capped Mesoporous Silica Nanoparticles for Redox and pH Triggered Drug Release In Vitro and In Vivo
Authors: Cai Yao , Deng Tian , Pan Yongxin , Zink Jeffrey I.
Published: August 2020

Mesoporous silica nanoparticles (MSNs) functionalized with redox‐sensitive or pH‐sensitive nanovalves for doxorubicin delivery and release by using recombinant human H chain ferritin (HFn) as a cap have been designed and fabricated. In both cases, transmission electron microscope observatory, dynamic light scattering change, Fourier transform infrared spectra examination, thermogravimetric analysis show that HFn can be chemically bonded to MSNs while retaining its ability to target transferrin receptor 1 (TfR1). Cargo loading and release studies demonstrate that HFn is an efficient capping agent, blocking the pores of MSN preventing cargo molecules from diffusing out, and is responsive to redox stimuli or pH changes. More importantly, HFn can not only cap the MSNs, but also enables targeted cargo delivery to malignant cells by binding to the TfR1 that has been overexpressed in various tumors, which can be reflected by the cell viability and fluorescence microscope analysis results comparing with cyclodextrin as the capping agent and TfR1 blocking assay. The in vivo study reveals the excellent efficacy of doxorubicin loaded and HFn capped MSNs on suppression of tumor growth. The new developed drug delivery system features mutually benefit and mutually support, providing strategy for achieving specific‐site therapeutics delivery systems.
Improved Quantum Yield and Excellent Luminescence Stability of Europium‐Incorporated Polymeric Hydrogen‐Bonded Heptazine Frameworks Due to an Efficient Hydrogen‐Bonding Effect
Authors: Yang Chaoqing , Folens Karel , Du Laing Gijs , Artizzu Flavia , Van Deun Rik
Published: August 2020

Two of the most persistent challenges for the high‐end application of luminescent lanthanide (Ln) compounds are a low quantum yield and luminescence quenching caused by a liquid medium. In this work, a type of polymeric hydrogen‐bonded heptazine framework is developed incorporating trivalent europium ions (P‐HHF‐Eu) via a low‐cost and facile low‐temperature thermal condensation reaction. Structural characterization clearly reveals that the solid‐phase pyrolyzation reaction results in the formation of P‐HHF‐Eu. Using time‐resolved and steady state photoluminescence (PL) spectroscopies, the photophysics and photochemistry of P‐HHF‐Eu at different hydration degrees are investigated and the role of hydrogen bonding in the significant enhancement of the emission properties is demonstrated. Furthermore, the P‐HHF‐Eu particles suspended in polyvinyl alcohol hydrogel exhibit excellent luminescence stability with a high PL quantum yield of up to ≈46% and wavelength responsive color‐tunable emission, which holds potential for security applications.
Bioresorbable Wireless Sensors as Temporary Implants for In Vivo Measurements of Pressure
Authors: Lu Di , Yan Ying , Deng Yujun , Yang Quansan , Zhao Jie , Seo Min‐Ho , Bai Wubin , MacEwan Matthew R. , Huang Yonggang , Ray Wilson Z. , Rogers John A.
Published: August 2020

Pressures at targeted locations inside the human body serve as critically important diagnostic parameters for monitoring various types of serious or even potentially fatal medical conditions including intracranial, intra‐abdominal, and pulmonary hypertension, as well as compartment syndromes. Implantable commercial sensors provide satisfactory accuracy and stability in measurements of pressure, yet surgical removal is required after recovery of the patient to avoid infections and other risks associated with long‐term implantation. Sensors that dissolve in biofluids (or, equivalently, bioabsorb or bioresorb) avoid the need for such surgeries, yet current designs involve either hard‐wired connections and/or fail to provide quantitative measurements over clinically relevant lifetimes. Here, a bioresorbable, wireless pressure sensor based on passive inductor‐capacitor resonance circuits in layouts and with sets of materials that overcome these drawbacks is reported. Specifically, optimized designs offer sensitivity as high as ≈200 kHz mmHg−1 and resolution as low as 1 mmHg. Encapsulation approaches that use membranes of Si3N4 and edge seals of natural wax support stable operation in vivo for up to 4 days. The bioresorbable pressure sensing technology reported here may serve as an important solution to temporary, real‐time monitoring of internal pressure for various medical conditions.
Self‐Assembly of Mechanoplasmonic Bacterial Cellulose–Metal Nanoparticle Composites
Authors: Eskilson Olof , Lindström Stefan B. , Sepulveda Borja , Shahjamali Mohammad M. , Güell‐Grau Pau , Sivlér Petter , Skog Mårten , Aronsson Christopher , Björk Emma M. , Nyberg Niklas , Khalaf Hazem , Bengtsson Torbjörn , James Jeemol , Ericson Marica B. , Martinsson Erik , Selegård Robert , Aili Daniel
Published: August 2020

Nanocomposites of metal nanoparticles (NPs) and bacterial nanocellulose (BC) enable fabrication of soft and biocompatible materials for optical, catalytic, electronic, and biomedical applications. Current BC–NP nanocomposites are typically prepared by in situ synthesis of the NPs or electrostatic adsorption of surface functionalized NPs, which limits possibilities to control and tune NP size, shape, concentration, and surface chemistry and influences the properties and performance of the materials. Here a self‐assembly strategy is described for fabrication of complex and well‐defined BC–NP composites using colloidal gold and silver NPs of different sizes, shapes, and concentrations. The self‐assembly process results in nanocomposites with distinct biophysical and optical properties. In addition to antibacterial materials and materials with excellent senor performance, materials with unique mechanoplasmonic properties are developed. The homogenous incorporation of plasmonic gold NPs in the BC enables extensive modulation of the optical properties by mechanical stimuli. Compression gives rise to near‐field coupling between adsorbed NPs, resulting in tunable spectral variations and enhanced broadband absorption that amplify both nonlinear optical and thermoplasmonic effects and enables novel biosensing strategies.
Evaporated SexTe1‐x Thin Films with Tunable Bandgaps for Short‐Wave Infrared Photodetectors
Authors: Tan Chaoliang , Amani Matin , Zhao Chunsong , Hettick Mark , Song Xiaohui , Lien Der‐Hsien , Li Hao , Yeh Matthew , Shrestha Vivek Raj , Crozier Kenneth B. , Scott Mary C. , Javey Ali
Published: August 2020

Semiconducting absorbers in high‐performance short‐wave infrared (SWIR) photodetectors and imaging sensor arrays are dominated by single‐crystalline germanium and III–V semiconductors. However, these materials require complex growth and device fabrication procedures. Here, thermally evaporated SexTe1‐x alloy thin films with tunable bandgaps for the fabrication of high‐performance SWIR photodetectors are reported. From absorption measurements, it is shown that the bandgaps of SexTe1‐x films can be tuned continuously from 0.31 eV (Te) to 1.87 eV (Se). Owing to their tunable bandgaps, the peak responsivity position and photoresponse edge of SexTe1‐x film‐based photoconductors can be tuned in the SWIR regime. By using an optical cavity substrate consisting of Au/Al2O3 to enhance its absorption near the bandgap edge, the Se0.32Te0.68 film (an optical bandgap of ≈0.8 eV)‐based photoconductor exhibits a cut‐off wavelength at ≈1.7 μm and gives a responsivity of 1.5 AW−1 and implied detectivity of 6.5 × 1010 cm Hz1/2 W−1 at 1.55 μm at room temperature. Importantly, the nature of the thermal evaporation process enables the fabrication of Se0.32Te0.68‐based 42 × 42 focal plane arrays with good pixel uniformity, demonstrating the potential of this unique material system used for infrared imaging sensor systems.
Effect of Porous and Nonporous Nanostructures on the Permeance of Positively Charged Nanofilm Composite Membranes
Authors: Sarkar Pulak , Modak Solagna , Karan Santanu
Published: August 2020

The role of the nanostructured materials incorporated in the separation layer of thin‐film composite membranes is not properly understood yet, as it requires stringent salt rejection values, proper imaging of the separation layer to realize the presence of nanostructured materials, and to know the thickness of the separation layer. Here, the scalable fabrication of high flux positively charged “polyamide composite nanofiltration” membranes with an ultrathin nanofilm separation layer of ≈14 nm produced via interfacial polymerization of polyethyleneimine and trimesoyl chloride is presented. “Polyamide nanocomposite nanofiltration” membranes are fabricated with the incorporation of different porous and nonporous nanostructures (e.g., ZIF‐8, TiO2, and Fe2O3 nanoparticles, graphene oxide, multi‐walled carbon nanotube, etc.) within the nanofilm separation layer. High water permeance of 15.4 L m−2 h−1 bar−1 (an increase of 33.9% compared to the pure nanofilm) is achieved with high rejection of MgCl2 (97.6%). Such membranes with enhanced water permeance surpass the upper bound of the permeance‐rejection of the state‐of‐the‐art positively charged nanofiltration membranes applicable for ionic and molecular separation.
Lipid Droplet‐Targetable Fluorescence Guided Photodynamic Therapy of Cancer Cells with an Activatable AIE‐Active Fluorescent Probe for Hydrogen Peroxide
Authors: Jiang Guoyu , Li Chunbin , Liu Xiang , Chen Qingqing , Li Xiaokang , Gu Xinggui , Zhang Pengfei , Lai Qingfang , Wang Jianguo
Published: August 2020

Fluorescence guided photodynamic therapy (FL‐PDT) offers the great opportunity for realizing personalized medicine in the treatment of cancer. Aggregation‐induced emission luminogens (AIEgens) with efficient emission and reactive oxygen species (ROS) generation even in the aggregated state are the ideal FL‐PDT photosensitizers to overcome the quenched fluorescence and ROS that traditional photosensitizers faced in PDT. Moreover, considering the higher levels of H2O2 in cancer cells than in normal cells and the fact that lipid droplet (LD) accumulation correlates to the enhanced survival rate of cancer cells in hypoxic conditions, it will be very interesting and rewarding to develop a LD‐targeted, H2O2 activatable AIE‐active photosensitizer for FL‐PDT. Thereafter, a LD‐targeted fluorescent probe TPECNPB is fabricated for H2O2‐activatable fluorescence guided PDT of cancer cells. AIE‐active TPECNPB exhibits the unique features of large Stokes shift (175 nm), superior photostability, and excellent selectivity toward H2O2. TPECNPB is able to selectively accumulate in LD and is activated by endogenous H2O2 for light‐up bioimaging in live MCF‐7 cells. In addition, H2O2‐activatable singlet oxygen generation and PDT of cancer cells has also been successfully implemented with TPECNPB. These prominent parameters would make TPECNPB a powerful toolbox for H2O2‐activatable and LD‐targetable fluorescence guided PDT of cancer cells.
Membrane‐Based Olefin/Paraffin Separations
Authors: Ren Yanxiong , Liang Xu , Dou Haozhen , Ye Chumei , Guo Zheyuan , Wang Jianyu , Pan Yichang , Wu Hong , Guiver Michael D. , Jiang Zhongyi
Published: August 2020

Efficient olefin/paraffin separation is a grand challenge because of their similar molecular sizes and physical properties, and is also a priority in the modern chemical industry. Membrane separation technology has been demonstrated as a promising technology owing to its low energy consumption, mild operation conditions, tunability of membrane materials, as well as the integration of physical and chemical mechanisms. In this work, inspired by the physical mechanism of mass transport in channel proteins and the chemical mechanism of mass transport in carrier proteins, recent progress in channel‐based and carrier‐based membranes toward olefin/paraffin separations is summarized. Further, channel‐based membranes are categorized into membranes with network structures and with framework structures according to the morphology of channels. The separation mechanisms, separation performance, and membrane stability in channel‐based and carrier‐based membranes are elaborated. Future perspectives toward membrane‐based olefin/paraffin separation are proposed.
Water‐Assisted Crystal Growth in Quasi‐2D Perovskites with Enhanced Charge Transport and Photovoltaic Performance
Authors: Li Xing , Wu Guangbao , Wang Mingchao , Yu Buyang , Zhou Jiyu , Wang Boxin , Zhang Xuning , Xia Haoran , Yue Shengli , Wang Kaiyuan , Zhang Chunfeng , Zhang Jianqi , Zhou Huiqiong , Zhang Yuan
Published: August 2020

Organic–inorganic hybrid quasi‐2D perovskites have shown excellent stability for perovskite solar cells (PSCs), while the poor charge transport in quasi‐2D perovskites significantly undermines their power conversion efficiency (PCE). Here, studies on water‐controlled crystal growth of quasi‐2D perovskites are presented to achieve high‐efficiency solar cells. It is demonstrated that the (BA)2MA4Pb5I16‐based PSCs (n = 5) processed with water‐containing precursors display an increased short‐circuit current density (Jsc) of 19.01 mA cm−2 and PCE over 15%. The enhanced performance is attributed to synergetic growths of the 3D and 2D phase components aided by the formed hydration (MAI∙H2O), leading to modulations on the crystal orientation and phase distribution of various n‐value components, which facilitate interphase charge transfer and charge sweepout throughout the device. The water‐assisted crystallization is further applied to triple cation‐based (BA)2(MA0.8FA0.15Cs0.05)4Pb5I16 quasi‐2D perovskites, which generate a remarkable PCE of 18.04%. Despite the presence of water in the precursors, the devices exhibit a satisfactory thermal stability with the PCE degradation <15% under continuous thermal aging at 60 °C for over 500 h.
Do investments in flexibility enhance sustainability? A simulative study considering the German electricity sector
Authors: Schäfer Pascal , Daun Torben M. , Mitsos Alexander
Published: August 2020

Current research concerning industrial demand side management primarily focuses on monetary aspects. Herein, we extend this perspective by assessing whether economically driven measures increasing the flexibility also result in reduced contributions to the residual load. For this purpose, we conduct a simulative study using historic and projected time series for the German electricity sector. First, Fourier analysis are performed to show that the main oscillation in the electricity price time series has a period length of 12 hr, whereas the renewable generation is primarily characterized by an oscillation with a period length of 24 hr. Second, a generic process model with capabilities for load shiftings is used to evaluate how the fluctuation patterns can be exploited via scheduling optimizations. Most importantly, our results demonstrate that prevalent price fluctuations prevent adequate monetary incentives for providing storage capacities for bridging up to 24 hr, which are desired for reducing the residual load.
Survival analysis in treated plasmablastic lymphoma patients: a population‐based study
Authors: Florindez Jorge A. , Alderuccio Juan P. , Reis Isildinha M. , Lossos Izidore S.
Published: August 2020

Herein we analyzed survival outcomes in chemotherapy‐treated patients with plasmablastic lymphoma (PBL) diagnosed between 2010 to 2016 (n = 248). Data was acquired from the Surveillance, Epidemiology, and End Results (SEER) 18 registries database (April 2019 release based on November 2018 submission). The majority of patients were male (81.9%) and younger than 60 years (71.0%). Oral and gastrointestinal (GI) sites were the most frequent primary extranodal locations (23% and 19.4%, respectively). Oral primary location was inversely associated with presence of B symptoms and advanced Ann‐Arbor stage. The 3‐year and 5‐year overall survival (OS) rates of treated PBL patients were 54% (95% CI: 46.5%‐60.8%) and 52.8% (95% CI: 45.2%‐59.8%). Three‐year conditional survival for 2‐year and 3‐year survivors were 90.3% and 97.8%, overlapping the survival of a general population matched by age, sex and calendar year. In a multivariable analysis, oral primary location was associated with not only better OS (HR 0.43; 95% CI: 0.21‐0.88, P = .021) but also better lymphoma‐specific survival (LSS) (SHR 0.36; 95% CI: 0.15‐0.86, P = .022); age ≥60 years was associated with shorter LSS (SHR 1.73; 95% CI: 1.02‐2.96, P = .043). Seven registries granted access to HIV status (n = 93) where HIV infection was detected in 52.7% of cases. The HIV status did not affect survival outcomes in unadjusted and adjusted analyses. We identified clinical characteristics associated with survival and showed that treated PBL patients may achieve long‐term survival.
Cyclic 1‐Azadienes in the Organocatalytic Inverse‐Electron‐Demand Aza‐Diels‐Alder Cycloadditions
Authors: Skrzyńska Anna , Frankowski Sebastian , Albrecht Łukasz
Published: August 2020

The inverse‐electron‐demand hetero‐Diels‐Alder (IEDHDA) reaction constitutes a useful and highly reliable method for the construction of various heterocycles. In the manuscript, a recent progress in the organocatalytic IEDHDA cycloaddition using cyclic 1‐azadienes as hetero‐dienes has been summarized and discussed. Since 2010 many interesting, new reactions involving these substrates have been identified and developed. They are based on various organocatalytic activation modes providing access to valuable nitrogen‐heterocycles. Excellent stereochemical reliability of asymmetric organocatalysis combined with the importance of the structural motifs obtained as a result of the cycloaddition makes these strategies highly relevant for the contemporary organic synthesis.
Evolution of Strategies in Paraconic Acids Synthesis
Authors: Fernandes Rodney A. , Chaudhari Dipali A. , Jha Amit K.
Published: August 2020

Various syntheses of different paraconic acids over the last seventeen years have been abstracted here. Paraconic acids have either a methylene or methyl group at the 4‐position of the γ‐butyrolactone with a common C‐3 carboxylic acid group and a long alkyl chain. Several possibilities of relative configurations give rise to distinct set of paraconic acids, which are also categorized in this review. Various strategies based on chiral catalytic methods, chiral pool, chiral auxiliary, resolution and other methods were engaged in the synthesis of different paraconic acids. A few members are yet to be synthesized and this compilation might entice future synthetic attempts on them.
Synthetic Organic Transformations of Transition‐Metal Nanoparticles as Propitious Catalysts: A Review
Authors: Ganesh Madhu , Ramakrishna Jayashree
Published: August 2020

Nanotechnology has produced compelling evidences in the field of catalysis, construction, electronics, energy, food, imaging, medical, packaging, pharmaceutical sectors and in water treatment. Nanoparticles of transition metal origin are enticing in catalytic applications due to their low‐lying empty orbitals for bonding and can offer a distinct ability to expand the coordination sphere. This coupled with ease of synthesis, recyclability and occurrence in abundance staples them as unique industrial materials. Transition metals such as Gold, Palladium, Silver, Copper, Iron, Ruthenium, Rhodium and hetero‐bimetallic versions have been in demand for various organic transformations. The sharp rise in number of literature reports justifies the stand in catalytic property. A unique ability to form Covalent and/or Van der Waals interactions with solid supports and activate the substrates through close functional group interactions renders them as effective entities in organic transformations. In this review, we present the new developments in this niche in the past five years with a retreat on the mechanistic aspects along with parameters involved in nanoparticle characterizations through advances in spectroscopy.
Blood neuro‐exosomal synaptic proteins predict Alzheimer's disease at the asymptomatic stage
Authors: Jia Longfei , Zhu Min , Kong Chaojun , Pang Yana , Zhang Heng , Qiu Qiongqiong , Wei Cuibai , Tang Yi , Wang Qi , Li Ying , Li Tingting , Li Fangyu , Wang Qigeng , Li Yan , Wei Yiping , Jia Jianping
Published: August 2020

Introduction

Exosomes are an emerging candidate for biomarkers of Alzheimer's disease (AD). This study investigated whether exosomal synaptic proteins can predict AD at the asymptomatic stage.

Methods

We conducted a two‐stage‐sectional study (discovery stage: AD, 28; amnestic mild cognitive impairment [aMCI], 25; controls, 29; validation stage: AD, 73; aMCI, 71; controls, 72), a study including preclinical AD (160) and controls (160), and a confirmation study in familial AD (mutation carriers: 59; non‐mutation carriers: 62).

Results

The concentrations of growth associated protein 43 (GAP43), neurogranin, synaptosome associated protein 25 (SNAP25), and synaptotagmin 1 were lower in AD than in controls (P < .001). Exosomal biomarker levels were correlated with those in cerebrospinal fluid (R2 = 0.54–0.70). The combination of exosomal biomarkers detected AD 5 to 7 years before cognitive impairment (area under the curve = 0.87–0.89).

Discussion

This study revealed that exosomal GAP43, neurogranin, SNAP25, and synaptotagmin 1 act as effective biomarkers for prediction of AD 5 to 7 years before cognitive impairment.
Direct and Selective Synthesis of Adipic and Other Dicarboxylic Acids by Palladium‐Catalyzed Carbonylation of Allylic Alcohols
Authors: Yang Ji , Liu Jiawang , Ge Yao , Huang Weiheng , Neumann Helfried , Jackstell Ralf , Beller Matthias
Published: August 2020

A general and direct synthesis of dicarboxylic acids including industrially important adipic acid by palladium‐catalyzed dicarbonylation of allylic alcohol is reported. Specifically, the combination of PdCl2 and a bisphosphine ligand (HeMaRaphos) promotes two different carbonylation reactions with high activity and excellent selectivity.
Biosynthesis of Quercetin Palmitate Esters and Evaluation of their Physico‐Chemical Properties and Stability
Authors: Saik Amy Yi Hsan , Lim Yau Yan , Stanslas Johnson , Choo Wee Sim
Published: August 2020

Quercetin was acylated with palmitic acid, catalyzed by either Candida antarctica lipase B (CAL‐B) or Pseudomonas cepacia lipase C (PCL‐C) to produce quercetin palmitate esters. The effects of various operating factors including incubation temperature, reaction duration, and molar ratio of substrates on the bioconversion yield, initial rate of reaction, and regioselectivity of the reactions were investigated. Three new esters were identified: quercetin 4′‐palmitate (C31H40O8, 540 g mol−1), quercetin 3′,4′‐dipalmitate (C47H70O9, 778 g mol−1), and quercetin 7,3′,4′‐tripalmitate (C63H100O10, 1016 g mol−1). The effects of incubation temperature, reaction duration, and molar ratio of substrates on bioconversion yields varied across the conditions. However, the highest bioconversion yield of 27.72 ± 1.64% was obtained with PCL‐C, at day 7, incubation temperature of 60 °C, quercetin:palmitic acid molar ratio of 1:20. The initial rate of reaction was significantly higher with PCL‐C. However, regioselectivity was similar for both PCL‐C‐ and CAL‐B‐catalyzed reactions with acylation occurred successively at 4´‐OH, 3´‐OH, and 7‐OH. Thin‐layer chromatography analysis showed that the three quercetin palmitate esters possessed enhanced lipophilicity (134% higher than quercetin). Besides, in silico investigation showed that quercetin 4′‐palmitate had a higher partition coefficient (log P) value than the parent compounds, indicating improved solubility. During gastrointestinal tract simulation, quercetin palmitate esters were recovered in the range of 71.03% to 79.36% after digestion, which were significantly higher than quercetin at 40.43 ± 8.71%. Quercetin 4′‐palmitate was also found stable over 28 days of storage. Due to improved lipophilicity, solubility, and stability, quercetin 4′‐palmitate has the potential to be used in topical applications.
Turning a Drug Target into a Drug Candidate: A New Paradigm for Neurological Drug Discovery?
Authors: Buckingham Steven D. , Mann Harry‐Jack , Hearnden Olivia K. , Sattelle David B.
Published: August 2020

The conventional paradigm for developing new treatments for disease mainly involves either the discovery of new drug targets, or finding new, improved drugs for old targets. However, an ion channel found only in invertebrates offers the potential of a completely new paradigm in which an established drug target can be re‐engineered to serve as a new candidate therapeutic agent. The L‐glutamate‐gated chloride channels (GluCls) of invertebrates are absent from vertebrate genomes, offering the opportunity to introduce this exogenous, inhibitory, L‐glutamate receptor into vertebrate neuronal circuits either as a tool with which to study neural networks, or a candidate therapy. Epileptic seizures can involve L‐glutamate‐induced hyper‐excitation and toxicity. Variant GluCls, with their inhibitory responses to L‐glutamate, when engineered into human neurons, might counter the excitotoxic effects of excess L‐glutamate. In reviewing recent studies on model organisms, it appears that this approach might offer a new paradigm for the development of candidate therapeutics for epilepsy.
Discovery and Characterization of a Novel Thermostable β‐Amino Acid Transaminase from a Meiothermus Strain Isolated in an Icelandic Hot Spring
Authors: Ferrandi Erica E. , Bassanini Ivan , Sechi Barbara , Vanoni Marta , Tessaro Davide , Guðbergsdóttir Sóley Ruth , Riva Sergio , Peng Xu , Monti Daniela
Published: August 2020

A Meiothermus strain capable of using β‐phenylalanine for growth is isolated by culture enrichment of samples collected in hot environments and the genome is sequenced showing the presence of 22 putative transaminase (TA) sequences. On the basis of phylogenetic and sequence analysis, a TA termed Ms‐TA2 is selected for further studies. The enzyme is successfully produced in Escherichia coli Rosetta(DE3) cells, with 70 mg of pure protein obtained from 1 L culture after purification by affinity chromatography. Ms‐TA2 shows high activity toward (S)‐β‐phenylalanine and other (S)‐β‐amino acids, as well as a preference for α‐ketoglutarate and aromatic aldehydes as amino acceptors. Moreover, Ms‐TA2 is shown to be a thermostable enzyme by maintaining about 60% of the starting activity after 3 h incubation at 50 °C and showing a melting temperature of about 73 °C. Finally, a homology‐based structural model of Ms‐TA2 is built and key active site interactions for substrate and cofactor binding are analyzed.
Online/at‐line measurement, analysis and control of product titer and critical product quality attributes (CQAs) during process development
Authors: Chemmalil Letha , Prabhakar Tanushree , Kuang June , West Jay , Tan Zhijun , Ehamparanathan Vivekh , Song Yuanli , Xu Jianlin , Ding Julia , Li Zhengjian
Published: August 2020

Process analytical technology (PAT) has been defined by the Food and Drug Administration as a system for designing, analyzing, and controlling manufacturing through timely measurements to ensure final product quality. Based on quality‐by‐design (QbD) principles, real‐time or near‐real‐time data monitoring is essential for timely control of critical quality attributes (CQAs) to keep the process in a state of control. To facilitate next‐generation continuous bioprocessing, deployment of PAT tools for real‐time monitoring is integral for process understanding and control. Real‐time monitoring and control of CQAs are essential to keep the process within the design space and align with the guiding principles of QbD. The contents of this manuscript are pertinent to the online/at‐line monitoring of upstream titer and downstream product quality with timely process control. We demonstrated that an ultra‐performance liquid chromatography (UPLC) system interfaced with a UPLC‐process sample manager (UPLC‐PSM) can be utilized to measure titer and CQAs directly from bioreactors and downstream unit operations, respectively. We established online titer measurements from fed‐batch and perfusion‐based alternating tangential flow bioreactors as well as product quality assessments of downstream operations for real‐time peak collection. This integrated, fully automated system for online data monitoring with feedback control is designed to achieve desired product quality.
Binding of Glutathione and ppGpp to Stringent Starvation Protein A (SspA)
Authors: Duysak Taner , Nguyen Le Phuong , Jung Che‐Hun
Published: August 2020

Stringent starvation protein A (SspA) is a glutathione S‐transferase homolog. In this study, his6‐tagged SspA from Escherischia coli has been cloned and over‐expressed. SspA binds glutathione and 1‐chloro‐2,4‐dinitrobenzene, the substrates for glutathione S‐transferases, with the dissociation constants as 225.0 ± 34.4 μM and 75.3 ± 4.3 μM, respectively. This observation is contradictory to the previous report that SspA, lacking glutathione S‐transferase activity, does not bind glutathione. It has been reported that SspA is an RNA polymerase‐associated transcription factor and that a functional relA gene is required for SspA to affect gene expression. A function of relA is to synthesize ppGpp, a global regulator in replication, transcription, and translation. This study shows for the first time that SspA binds ppGpp with the dissociation of constants of 109.1 ± 7.2 μM. This study may provide an insight why relA is required for regulating gene expression by SspA.
Board interlocks and greenhouse gas emissions
Authors: Lu Jing , Yu Dongning , Mahmoudian Fereshteh , Nazari Jamal A. , Herremans Irene M.
Published: August 2020

Using resource dependence theory, we analyze board interlocks, their industry origin, and their relationship to firms' greenhouse gas (GHG) emissions. Interlocks create connections by having board members from one firm sit on other firms' boards, providing an avenue for sharing information and resources to aid in knowledge transfer and capability development. As firms face challenges for improved GHG emissions performance, they may look to their board members' connections to other firms to acquire needed resources. Using a sample of US Standard & Poor's (S&P) 1500 firms for years 2009 to 2018, we find that firms with a greater number of board interlocks achieve lower GHG emissions intensity. We also find that boards for the best performing companies have interlocks in the same industry, in other industries, and with firms leading in GHG emissions intensity, especially for firms in higher environmentally impacting industries, as they face greater emissions challenges.
How others respond to non‐suicidal self‐injury disclosure: A systematic review
Authors: Park Yeonsoo , Mahdy Jasmine C. , Ammerman Brooke A.
Published: August 2020

Non‐suicidal self‐injury (NSSI) is an increasing health concern. Despite the potential benefits of disclosing the behaviour, many decide not to do so because of the fear of negative social reactions. In this review, we examined the existing research on reported and perceived reactions to NSSI disclosure with the aim of identifying how an individual who discloses their NSSI perceives others' responses to this disclosure, with the ultimate goal of understanding how these reactions may impact those who disclose their NSSI. Among the initial 275 studies, 10 fit the inclusion criteria. Three studies reported perceived responses by individuals who had disclosed their NSSI; six studies examined self‐reported responses by others; one study focused on disclosures online. Individuals who disclosed their NSSI often received negative responses, which caused them to withdraw from seeking further help. On the other hand, recipients' reactions to NSSI disclosure varied based on NSSI characteristics such as its perceived cause and/or underlying motivation. Results highlight the importance of providing support rather than searching for the underlying drives of NSSI.
What COVID‐19 could mean for security operations during fall athletics
Authors: Rahn Josh
Published: August 2020

Fall and winter collegiate sports are in uncertain territory this year, thanks to the COVID‐19 pandemic. As of this writing, administrators are still digesting the numbers and listening to their respective public health experts as to whether fall sports will move forward at all, much less whether such events will have spectators.
Competency‐based education in undergraduate clinical prosthodontics: A paradigm shift in training
Authors: Alkhodary Mohamed A. , Farah Ra'fat I. , Ghobashy Atef I.
Published: August 2020

Introduction

Competency‐based education (CBE) is thought to improve the quality of dental graduates than traditional education (TE). This study compared the students' final scores in clinical training of prosthodontics using CBE versus TE.

Materials and Methods

This study enrolled 459 fourth‐ and fifth‐year undergraduate students. Of the participants, 231 students (143 males and 88 females) attended TE and 228 (128 males and 100 females) attended CBE. This study considered the final scores that the students achieved for their competency cases and compared it with the scores achieved during the TE process. Statistical analysis of results used the Mann–Whitney U test for nonparametric numbers.

Results

The mean score of the clinical examination for all students in clinical prosthodontics courses was 81.4 (maximum and minimum scores: 95.0 and 41.3, respectively). The mean scores in the traditional and competency‐based education groups were 79.9 ± 6.48 and 82.9 ± 6.87, respectively. Scores in the competency education group (mean rank = 265.08) were statistically significantly higher than in the conventional education group (mean rank = 195.38) with U = 18,336, z = −5.631, and p < .001.

Conclusions

The application of CBE allowed the students to achieve higher scores in prosthodontics than the TE.
An Enzyme Containing the Conserved Domain of Unknown Function DUF62 Acts as a Stereoselective (Rs,Sc)‐S‐Adenosylmethionine Hydrolase
Authors: Kornfuehrer Taylor , Romanowski Sean , de Crécy‐Lagard Valérie , Hanson Andrew D. , Eustáquio Alessandra S.
Published: August 2020

Homochirality is a signature of biological systems. The essential and ubiquitous cofactor S‐adenosyl‐l‐methionine (SAM) is synthesized in cells from adenosine triphosphate and l‐methionine to yield exclusively the (S,S)‐SAM diastereomer. (S,S)‐SAM plays a crucial role as the primary methyl donor in transmethylation reactions important to the development and homeostasis of all organisms from bacteria to humans. However, (S,S)‐SAM slowly racemizes at the sulfonium center to yield the inactive (R,S)‐SAM, which can inhibit methyltransferases. Control of SAM homochirality has been shown to involve homocysteine S‐methyltransferases in plants, insects, worms, yeast, and in ∼18 % of bacteria. Herein, we show that a recombinant protein containing a domain of unknown function (DUF62) from the actinomycete bacterium Salinispora tropica functions as a stereoselective (R,S)‐SAM hydrolase (adenosine‐forming). DUF62 proteins are encoded in the genomes of 21 % of bacteria and 42 % of archaea and potentially represent a novel mechanism to remediate SAM damage.
Management of calcified coronary artery bifurcation lesions
Authors: Patel Nileshkumar J. , Okamoto Naotaka , Murphy Jonathan , Vengrenyuk Yuliya , Sharma Samin K. , Kini Annapoorna S.
Published: August 2020

Calcified coronary artery bifurcation lesions (CBL) remain a challenge for the interventional cardiologist. Evidence regarding treatment of CBL is minimal. Optimal plaque modification is the most important step prior to stent deployment. Provisional stenting is the preferred strategy for most bifurcation lesions. However, two‐stent strategy should be considered for BL with compromised large SB (>2.5 mm) supplying a large territory, >70% SB stenosis and lesions more than 5 mm long. In this contemporary review article, we present a simplified approach to treating CBL and demonstrate the approach to specific case examples using our newly developed mobile application, BifurcAID.
Dramatic motor recovery following recanalization in bilateral pontine infarct with restricted diffusion
Authors: Mahajan Arnav , Komonchan Surasak , Na Songkhla Krida , Boontaworn Anchulee , Nosai Supalak
Published: August 2020

On findings of restricted diffusion in a bilateral pontine infarct, imaging solely may not predict a poor clinical outcome as a full motor recovery is possible. Hence, recanalization of an acutely occluded basilar artery should be carefully considered on a case by case basis.
Covalent Organic Frameworks for Next‐Generation Batteries
Authors: Chen Xiudong , Sun Weiwei , Wang Yong
Published: August 2020

The demand for energy storage is increasing with the development of an electronic society. A key to improving the electrochemical performance of advanced batteries is to develop advanced electrode materials. Currently, electrode studies mainly focus on the development of materials with a high energy density and high power density by regulating the morphological structure, but most of the electrodes are inorganic materials, which may bring serious problems, such as high recycling costs and environmental pollution. Covalent organic frameworks (COFs) that are environmentally friendly and possess adjustable structures have become a series of promising organic electrode materials for rechargeable advanced batteries and have attracted great attention in recent years. Precisely customized COFs can be achieved by adjusting the pore size and pore configuration and introducing functional groups into the framework through pre‐synthesis and post‐synthesis strategies, and these methods provide the possibility of obtaining high‐performance organic electrode materials. In this review, the latest research progress and perspective on using COFs as electrode materials for next‐generation batteries, including sodium‐ion batteries, potassium‐ion batteries, lithium‐sulfur batteries, lithium‐metal batteries, zinc‐ion batteries, magnesium‐ion batteries, and aluminum‐ion batteries, are summarized. The relative energy‐storage mechanism, advantages and challenges of COF electrodes, as well as the corresponding strategies used to achieve better electrochemical performances, are also presented.
Experimental methods in chemical engineering: Process simulation
Authors: De Tommaso Jacopo , Rossi Francesco , Moradi Nooshin , Pirola Carlo , Patience Gregory S. , Galli Federico
Published: August 2020

Process simulation software designs equipment, simulates operations, optimizes a plant's configuration (heat exchangers network, for example), estimates operating and capital expenses, and serves as an educational tool. However, mastering the theoretical background minimizes common mistakes such as applying an incorrect thermodynamic method, selecting improper algorithms in the case of tear systems, and setting irrational system specifications. Engineers and researchers will exploit this tool more often in the future as constant advancements in simulation science as well as new models are released continually. Process simulators make it easier to build digital twins and thus will facilitate the implementation of the industry 4.0 guidelines. We highlight the mathematical and technical features of process simulators, as well as the capabilities and the fields of application. A bibliometric map of keywords from articles citing Aspen+, Aspen plus, Hysys, and Pro/II indexed by Web of Science between 2017 and 2020 identified the main research clusters, such as design, optimization, energy or exergy, biomass; H2 and CO2 capture, thermodynamics; and separations and techno‐economic analysis.
Synthesis of Self‐Ordered Tantalum‐Niobium Mixed Oxide Nanotubes and Their Use for Clean Hydrogen Production
Authors: Ahmed Nashaat , Hafez Ahmed M. , Salama Mohamed , Allam Nageh K.
Published: August 2020

We report on the first fabrication of vertically‐oriented tantalum‐niobium mixed oxide nanotube arrays (Ta−Nb−O NTs) via one‐step anodization of Ta−Nb alloy sheet in NH4F‐containing electrolytes. The synthesized Ta−Nb−O NTs were fully characterized via X‐ray diffraction (XRD), field‐emission scanning electron microscopy (FESEM), high‐resolution transmission electron microscopy (HRTEM), and X‐ray photoelectron spectroscopy (XPS). The prepared nanotubes have an average diameter of ∼35 nm with a wall thickness ∼15 nm and a length ∼1.0 μm. The photoactivity of the fabricated Ta−Nb−O NTs was tested toward the photocatalytic hydrogen production, revealing a steady rate with no indication of activity poisoning. The amount of hydrogen produced can be as high as 150 μL/cm2 after 5 h of illumination, which is much higher than that reported for most metal oxides. Therefore, the demonstrated platform of Ta−Nb−O nanotube arrays holds promise for a variety of solar energy applications.
Whale optimization algorithm based on nonlinear convergence factor and chaotic inertial weight
Authors: Ding Hangqi , Wu Zhiyong , Zhao Luchen
Published: August 2020

The whale optimization algorithm (WOA) is a new biological meta‐heuristic algorithm based on the social hunting behaviors of humpback whales. However, it can easily fall into a local optimum when solving complex problems and exhibits slow convergence speed and poor exploration. This study proposed three improved versions of the WOA based on the concepts of chaos initialization, nonlinear convergence factor, and chaotic inertial weight to enhance its exploration abilities. These properties were employed to improve the population diversity and maintain the balance between exploration and exploitation. The performance of the best version was compared with those of moth‐flame optimization, firefly algorithm, particle swarm optimization, gray wolf optimizer, flower pollination algorithm, original WOA, and two recently proposed hybrid WOA through 19 benchmark functions. Experimental results indicated that the proposed algorithms exhibit better performance in terms of complexity and convergence speed.
Corporate social responsibility intensity, management earnings forecast accuracy, and investor trust: Evidence from Japan
Authors: Suto Megumi , Takehara Hitoshi
Published: August 2020

This study examines whether and how corporate social responsibility (CSR) intensity affects investment performance directly, as a signal of investor trust, and indirectly, by impacting management earnings forecasts accuracy. We find that investors benefit from high CSR firms as they avoid unexpected stock volatility while paying the cost of CSR by lowering returns. The results suggest that CSR intensity stabilizes stock returns for high CSR firms in the long run and moderates management disclosure bias in the short run. Our findings imply that CSR activities based on stakeholder relationships would help signal firm‐level trust and restrain myopic investment in the capital market. Stakeholder engagement in order to build investor trust is not only essential for corporate sustainability and long‐term success but also a key determinant in well‐functioning capital markets with unstable public trust in business and finance.
Comparative analysis on Hopf bifurcation of integer‐order and fractional‐order two‐neuron neural networks with delay
Authors: Xu Changjin , Aouiti Chaouki
Published: August 2020

This article mainly focuses on the stability and the existence of Hopf bifurcation of integer‐order and fractional‐order two‐neuron neural networks with delay. First of all, we obtain the sufficient criterion to ensure the stability and the existence of Hopf bifurcation of integer‐order two‐neuron neural networks with delay. Next, we establish the sufficient condition guaranteeing the stability and the existence of Hopf bifurcation of fractional‐order two‐neuron neural networks with delay. The study reveals that the time delay has a vital effect on the stability and Hopf bifurcation of integer‐order and fractional‐order two‐neuron neural networks with delay. By comparative analysis on Hopf bifurcation for integer‐order and fractional‐order two‐neuron neural networks with delay, we find that under an appropriate parameter conditions, the stability region can be enlarged, and the time of appearance of Hopf bifurcation of the involved two‐neuron neural networks can be postponed by using fractional‐order case. Finally, computer simulation results are presented to illustrate the theoretical findings. The established results of this article play an important role in designing and controlling networks.
Break Binge Eating: Reach, engagement, and user profile of an Internet‐based psychoeducational and self‐help platform for eating disorders
Authors: Linardon Jake , Rosato John , Messer Mariel
Published: August 2020

Objectives

Internet‐based psychoeducational and self‐help platforms hold promise for alleviating existing help‐seeking barriers and addressing the unmet needs of people with eating disorders (EDs). In this paper, we report data related to the reach, engagement, and visitor profile of Break Binge Eating, an online platform designed to provide evidence‐based information and self‐help strategies for people at all stages of an ED.

Method

Two sources of data were presented: (a) usage data from platform visitors generated through Google Analytics; and (b) characteristics of a sample of platform visitors (n = 786).

Results

In 13 months, approximately 46,311 unique users worldwide have accessed this platform, with usage rates rapidly increasing each month. Most visitors came from organic searches (when ED‐related information is directly searched in a browser). Self‐help content was the most accessed material, and 81% of the sample stated that their reason for accessing the platform was to get help. Sample visitors were highly symptomatic; 52% met criteria resembling a threshold ED and 87% engaged in at least one ED behavior in the past month. Across different symptomatic subgroups, ∼50% were unsure whether they needed help, ∼80% were not receiving any help, and ∼75% were highly concerned with their symptoms.

Conclusion

This online platform has broad reach and is engaging its intended audience. It is an aim of this platform to improve mental health literacy, facilitate symptom recognition and improvement, and alleviate help‐seeking barriers. Evaluating whether this platform is achieving its intended aims in a randomized controlled trial is the next step.
A Novel Electrochemical Sensor for Simultaneous Determination of Hydroquinone, Catechol, and Resorcinol Using a Carbon Paste Electrode Modified by Zn‐MOF, Nitrogen‐doped Graphite, and AuNPs
Authors: Mashhadizadeh Mohammad Hossain , Kalantarian S. Marzieh , Azhdeh Afsaneh
Published: August 2020

In this work, the carbon paste electrode was modified with a composite of a metal‐organic framework, nitrogen‐doped graphite, and gold nanoparticles and used as an electrochemical sensor for dihydroxybenzene isomers. The morphology and characteristics of the modifiers were found by SEM and FT‐IR. Electrochemical techniques showed the specific surface of the electrode to be significantly enhanced. The outcome achieved shows that this novel sensor displays an excellent electro‐catalytic activity towards the oxidation of these isomers. The sensor was applied to the simultaneous determination of each three isomers using DPV with a linear response in the concentration range of 5–105 nM.