bluuebunny/crossref_metadata_2025 huggingface dataset:
Reproducibility of liver iron concentration estimates in MRI through R2* measurement determined by least‐squares curve fitting
Authors: Headley Andrew M. , Grice Jared V. , Pickens David R.
Published: November 2020

Measuring transverse relaxation rate (R2* = 1/T2*) via MRI allows for noninvasive evaluation of multiple clinical parameters, including liver iron concentration (LIC) and fat fraction. Both fat and iron contribute to diffuse liver disease when stored in excess in the liver. This liver damage leads to fibrosis and cirrhosis with an increased risk of developing hepatocellular carcinoma. Liver iron concentration is linearly related to R2* measurements using MRI. A phantom was constructed to assess R2* quantification variability on 1.5 and 3 T MRI systems. Quantification was executed using least‐squares curve fitting techniques. The phantom was created using readily available, low‐cost materials. It contains four vials with R2* values that cover a clinically relevant range (100 to 420 Hz at 1.5 T). Iron content was achieved using ferric chloride solutions contained in glass vials, each affixed in a three‐dimensional (3D)‐printed polylactide (PLA) structure, surrounded by distilled water, all housed in a sealed acrylic cylinder. Multiple phantom stands were also 3D‐printed using PLA for precise orientation of the phantom with respect to the direction of the static magnetic field. Acquisitions at different phantom angles, across multiple MRI systems, and with different pulse sequence parameters were evaluated. The variability between any two R2* measurements, taken in the same vial under these various acquisition conditions, on a 1.5 T MRI system, was <7% for each of the four vials. For 3 T MRI systems, variability was less than 14% in all cases. Variability was <6% for both 1.5 and 3 T acquisitions when unchanged pulse sequence parameters were used. The phantom can be used to mimic a range of clinically relevant levels of R2* relaxation rates, as measured using MRI. These measurements were found to be reproducible relative to the gold‐standard method, liver biopsy, across several different image acquisition conditions.
Rational Design of Metal Oxide‐Based Heterostructure for Efficient Photocatalytic and Photoelectrochemical Systems
Authors: Xia Chengkai , Wang Heng , Kim Jung Kyu , Wang Jingyu
Published: November 2020

Solar‐driven photo‐to‐chemical conversion is an interesting approach for energy harvesting and storage with high sustainability. To achieve high photo‐to‐chemical conversion efficiency, it is important to develop cost‐effective and stable catalysts with high activity. Metal oxides provide an interesting platform for the development of efficient catalysts owing to their abundance, high stability, and tunable band edges. Their performance highly depends on the rational design of heterostructures with engineered electronic structures, modified charge migration behavior, tailored interfacial properties, and amplified electromagnetic fields. All these enable the achievement of efficient light harvesting, promoted charge separation and transport, and accelerated surface reactions. Herein, a recent study on rationally designed metal oxide heterostructures for enhancing photo‐to‐chemical energy conversion via photocatalytic and photoelectrochemical systems is reviewed. The approaches to enhance their conversion efficiency are as follows: 1) surface modification via loading of plasmonic metals and other photosensitizers; 2) surface regulation, including morphology, defect, and dopants; 3) interfacial assembly with metal oxides, other metal compounds, and metal‐free materials. Moreover, the underlying reaction mechanisms of metal oxide‐based heterostructures and how they affect the energy conversion efficiency are discussed. Finally, the challenges and perspectives on the development of metal oxide‐based heterostructures and associated photo‐to‐chemical devices are presented.
Digitally Fabricated and Naturally Augmented In Vitro Tissues
Authors: Duarte Campos Daniela F. , De Laporte Laura
Published: November 2020

Human in vitro tissues are extracorporeal 3D cultures of human cells embedded in biomaterials, commonly hydrogels, which recapitulate the heterogeneous, multiscale, and architectural environment of the human body. Contemporary strategies used in 3D tissue and organ engineering integrate the use of automated digital manufacturing methods, such as 3D printing, bioprinting, and biofabrication. Human tissues and organs, and their intra‐ and interphysiological interplay, are particularly intricate. For this reason, attentiveness is rising to intersect materials science, medicine, and biology with arts and informatics. This report presents advances in computational modeling of bioink polymerization and its compatibility with bioprinting, the use of digital design and fabrication in the development of fluidic culture devices, and the employment of generative algorithms for modeling the natural and biological augmentation of in vitro tissues. As a future direction, the use of serially linked in vitro tissues as human body‐mimicking systems and their application in drug pharmacokinetics and metabolism, disease modeling, and diagnostics are discussed.
Microbubbles Containing Lysolipid Enhance Ultrasound‐Mediated Blood–Brain Barrier Breakdown In Vivo
Authors: Vince Oliver , Peeters Sarah , Johanssen Vanessa A. , Gray Michael , Smart Sean , Sibson Nicola R. , Stride Eleanor
Published: November 2020

Ultrasound and microbubbles (MBs) offer a noninvasive method of temporarily enhancing blood–brain barrier (BBB) permeability to therapeutics. To reduce off‐target effects, it is desirable to minimize the ultrasound pressures required. It has been shown that a new formulation of MBs containing lysolipids (Lyso‐MBs) can increase the cellular uptake of a model drug in vitro. The aim of this study is to investigate whether Lyso‐MBs can also enhance BBB permeability in vivo. Female BALB/c mice are injected with either Lyso‐MBs or control MBs and gadolinium‐DTPA (Gd‐DTPA) and exposed to ultrasound (500 kHz, 1 Hz pulse repetition frequency, 1 ms pulse length, peak‐negative pressures 160–480 kPa) for 2 min. BBB permeabilization is measured via magnetic resonance imaging (7.0 T) of Gd‐DTPA extravasation and subsequent histological examination of brain tissue to assess serum immunoglobulin G (IgG) extravasation (n = 8 per group). An approximately twofold enhancement in BBB permeability is produced by the Lyso‐MBs at the highest ultrasound pressure compared with the control. These findings indicate that modifying the composition of phospholipid‐shelled MBs has the potential to improve the efficiency of BBB opening, without increasing the ultrasound pressure amplitude required. This is particularly relevant for delivery of therapeutics deep within the brain.
Rational Design of Ni‐Based Electrocatalysts by Modulation of Iron Ions and Carbon Nanotubes for Enhanced Oxygen Evolution Reaction
Authors: Song Daqi , Wang Liang , Yao Mengyao , Sun Weiwei , Vajtai Robert , Ajayan Pulickel M. , Wang Yong
Published: November 2020

Although Ni‐based compounds perform well as oxygen evolution reaction (OER) catalysts, several challenges hinder their potential applications, namely, complicated synthesis and pyrolysis, poor conductivity, and poor stability. Herein, a facile large‐scale synthesis strategy is designed for unique Fe‐doped Ni‐based metal‐organic polymer@carbon nanotubes (CNTs) composites that may be used as OER electrocatalysts without further treatment. The Ni1.95Fe‐MOP@CNTs deliver a small overpotential of 256 mV to achieve a current density of 10 mA cm−2, and their Tafel slope is low to 58 mV dec−1. In addition, the catalyst displays high durability after a long‐term test of 60 000 s. Introducing Fe ions and CNTs into Ni‐based compounds increases the surface area and enhances the degree of graphitization and the composite conductivity, contributing to the excellent catalytic performance. The charge transfer reaction dynamics are explored using in situ differential electrochemical mass spectrometry. Surprisingly, the Ni1.95Fe‐MOP@CNTs demonstrate a Faraday efficiency of (≈92.7%) for O2 production. These findings pave a new way for synthesizing catalysts without post‐processing for water oxidation.
Seamlessly Splicing Metallic SnxMo1−xS2 at MoS2 Edge for Enhanced Photoelectrocatalytic Performance in Microreactor
Authors: Shao Gonglei , Lu Yizhen , Hong Jinhua , Xue Xiong‐Xiong , Huang Jinqiang , Xu Zheyuan , Lu Xiangchao , Jin Yuanyuan , Liu Xiao , Li Huimin , Hu Sheng , Suenaga Kazu , Han Zheng , Jiang Ying , Li Shisheng , Feng Yexin , Pan Anlian , Lin Yung‐Chang , Cao Yang , Liu Song
Published: November 2020

Accurate design of the 2D metal–semiconductor (M–S) heterostructure via the covalent combination of appropriate metallic and semiconducting materials is urgently needed for fabricating high‐performance nanodevices and enhancing catalytic performance. Hence, the lateral epitaxial growth of M–S SnxMo1−xS2/MoS2 heterostructure is precisely prepared with in situ growth of metallic SnxMo1−xS2 by doping Sn atoms at semiconductor MoS2 edge via one‐step chemical vapor deposition. The atomically sharp interface of this heterostructure exhibits clearly distinguished performance based on a series of characterizations. The oxygen evolution photoelectrocatalytic performance of the epitaxial M–S heterostructure is 2.5 times higher than that of pure MoS2 in microreactor, attributed to the efficient electron–hole separation and rapid charge transfer. This growth method provides a general strategy for fabricating seamless M–S lateral heterostructures by controllable doping heteroatoms. The M–S heterostructures show increased carrier migration rate and eliminated Fermi level pinning effect, contributing to their potential in devices and catalytic system.
London Dispersion Interactions Rather than Steric Hindrance Determine the Enantioselectivity of the Corey–Bakshi–Shibata Reduction
Authors: Eschmann Christian , Song Lijuan , Schreiner Peter R.
Published: November 2020

The well‐known Corey–Bakshi–Shibata (CBS) reduction is a powerful method for the asymmetric synthesis of alcohols from prochiral ketones, often featuring high yields and excellent selectivities. While steric repulsion has been regarded as the key director of the observed high enantioselectivity for many years, we show that London dispersion (LD) interactions are at least as important for enantiodiscrimination. We exemplify this through a combination of detailed computational and experimental studies for a series of modified CBS catalysts equipped with dispersion energy donors (DEDs) in the catalysts and the substrates. Our results demonstrate that attractive LD interactions between the catalyst and the substrate, rather than steric repulsion, determine the selectivity. As a key outcome of our study, we were able to improve the catalyst design for some challenging CBS reductions.
Functional expression of eukaryotic cytochrome P450s in yeast
Authors: Jiang Lihong , Huang Lei , Cai Jin , Xu Zhinan , Lian Jiazhang
Published: November 2020

Cytochrome P450 enzymes (P450s) are a superfamily of heme‐thiolate proteins widely existing in various organisms. Due to their key roles in secondary metabolism, degradation of xenobiotics, and carcinogenesis, there is a great demand to heterologously express and obtain a sufficient amount of active eukaryotic P450s. However, most eukaryotic P450s are endoplasmic reticulum‐localized membrane proteins, which is the biggest challenge for functional expression to high levels. Furthermore, the functions of P450s require the cooperation of cytochrome P450 reductases for electron transfer. Great efforts have been devoted to the heterologous expression of eukaryotic P450s, and yeasts, particularly Saccharomyces cerevisiae are frequently considered as the first expression systems to be tested for this challenging purpose. This review discusses the strategies for improving the expression and activity of eukaryotic P450s in yeasts, followed by examples of P450s involved in biosynthetic pathway engineering.
Ten‐year‐old boy with atypical COVID‐19 symptom presentation: A case report
Authors: Houshmand Hamidreza , Abounoori Mahdi , Ghaemi Reza , Bayat Sara , Houshmand Gholamreza
Published: November 2020

Since reactive arthritis (ReA) and urticaria could be seen in this age group along with atypical COVID‐19 symptom presentation, pediatrics should be familiar with urticarial rashes and ReA in COVID‐19 to enable early diagnoses of infected individuals.
Interfacial Engineering in a Cathode Composite Based on Garnet‐Type Solid‐State Li‐Ion Battery with High Voltage Cycling
Authors: Balasubramaniam Ramkumar , Nam Chan‐Woo , Aravindan Vanchiappan , Eum Donggun , Kang Kisuk , Lee Yun‐Sung
Published: November 2020

Garnet‐type solid electrolyte is a promising candidate for the fabrication of high energy all‐solid‐state Li‐ion batteries (ASSLIBs), but its use is hampered by a large interfacial resistance. Herein, we propose a surface modification and subsequent sintering to enhance the interfacial connection between the cathode and the solid electrolyte. The ASSLIB prepared by this method delivered an initial discharge capacity of ∼66 mAh g−1 (80 °C) at a rate of 0.1 C. However, the poor contact between the cathode and electrolyte triggered the increase of the interfacial resistance, which caused severe capacity decay upon cycling. The encapsulation of LiCoO2 particles with LiBO2 using a single‐step sintering process dramatically increased the interfacial contact, resulting in a higher discharge capacity of 116 mAh g−1 with good cycling behavior. Therefore, surface modification of the cathode offers a reduction of resistance and promotes efficient Li‐ion transfer pathways across the cathode/solid‐electrolyte interface.
Carbon Nanodots in Electrochemical Sensors and Biosensors: A Review
Authors: Hassanvand Zahra , Jalali Fahimeh , Nazari Maryam , Parnianchi Fatemeh , Santoro Carlo
Published: November 2020

This Review presents the latest advances in designing electrochemical sensors by using carbon nanodots (CNDs), carbon dots (CDs), and graphene quantum dots (GQDs), as a new class of photoluminescent nanomaterials, which can be employed in a vast number applications, such as biomedicine, biosensing, optical sensing, catalysis, solar cells, imaging, and electrochemical sensing. Recently, the application of CDs and GQDs in electrochemical sensing has increased significantly because of their unique features such as quantum size, excellent biocompatibility, enzyme‐like activity, high active area, and abundance of hydrophilic groups, such as hydroxyl, carboxyl, or amine functionalities. The applications of CDs and GQDs for the electrochemical sensing of hydrogen peroxide, glucose, other organic molecules, as well as metal ions are presented. The utilization of CDs and GQDs for immunosensing and aptasensing is also reported.
Facile Synthesis of Size‐Controlled Nitrogen‐Doped Mesoporous Carbon Nanosphere Supported Ultrafine Ru Nanoparticles for Selective Hydrogenation of Quinolines
Authors: Tian Zhengbin , Jiang Haibin , Huang Minghua , Wang Guang‐Hui
Published: November 2020

Nitrogen‐doped mesoporous carbon nanosphere (NMCS) with tunable sizes and uniform mesoporosity was synthesized by a facile soft‐templating method. During the synthesis, F127 (PEO–PPO–PEO triblock copolymer) could be used not only as a soft template to generate the mesostructure but also as a size‐control agent to tailor the size of NMCS in a relatively wide range of 100 to 700 nm. In addition, the synthesis process was simple and suitable for large‐scale production. Moreover, the NMCS was used as support of ultrafine Ru nanoparticles (Ru/NMCS), which exhibited good catalytic performances for selective hydrogenation of quinolones. It is expected that the simple synthetic strategy for the NMCS can generate extensive interest in many catalysis and sorption applications.
Aromatic Aza‐Claisen Rearrangement of Arylpropargylammonium Salts Generated in situ from Arynes and Tertiary Propargylamines
Authors: Han Lu , Li Sheng‐Jun , Zhang Xue‐Ting , Tian Shi‐Kai
Published: November 2020

The charge‐accelerated aza‐Claisen rearrangement of ammonium salts serves as a key step in the construction of complex nitrogen‐containing molecules. However, much less attention has been paid to the aromatic aza‐Claisen rearrangement than to the aliphatic one. Herein, we report an unprecedented aromatic aza‐Claisen rearrangement of arylpropargylammonium salts, generated in situ from arynes and tertiary propargylamines, delivering structurally diverse 2‐propargylanilines in moderate to good yields with high regioselectivity. This rearrangement proceeds in the absence of strong bases or transition metals, is compatible with moisture and air, tolerates a wide variety of functional groups, and is amenable to forming 11‐ to 13‐membered heterocycles with a triple bond. The 2‐propargylaniline products were treated with aluminum chloride in ethanol to afford multisubstituted indoles in moderate to excellent yields. Finally, a series of deuterium‐labeling experiments was performed to elucidate the reaction mechanism.
The Aggregation Pattern of Aβ1–40 is Altered by the Presence of N‐Truncated Aβ4–40 and/or CuII in a Similar Way through Ionic Interactions
Authors: Stefaniak Ewelina , Atrian‐Blasco Elena , Goch Wojciech , Sabater Laurent , Hureau Christelle , Bal Wojciech
Published: November 2020

Alzheimer's disease (AD) is one of the most common of the multifactorial diseases and is characterized by a range of abnormal molecular processes, such as the accumulation of extracellular plaques containing the amyloid‐β (Aβ) peptides and dyshomeostasis of copper in the brain. In this study, we have investigated the effect of CuII on the aggregation of Aβ1–40 and Aβ4–40, representing the two most prevalent families of Aβ peptides, that is, the full length and N‐truncated peptides. Both families are similarly abundant in healthy and AD brains. For either of the studied peptides, substoichiometric CuII concentrations accelerated aggregation, whereas superstoichiometric CuII inhibited fibril formation, likely by stabilizing the oligomers. The addition of either Aβ4–40 or substoichiometric CuII affected the aggregation profile of Aβ1–40, by yielding shorter and thicker fibrils; amorphous aggregates were formed in the presence of a molar excess of CuII. The similarity of these two effects can be attributed to the increase in the positive charge on the Aβ N terminus, caused both by CuII complexation and N truncation at position 4. Our findings provide a better understanding of the biological Aβ aggregation process as these two Aβ species and CuII coexist and interact under physiological conditions.
Construction of Helical Structures with Multiple Fused Anthracenes: Structures and Properties of Long Expanded Helicenes
Authors: Fujise Kei , Tsurumaki Eiji , Wakamatsu Kan , Toyota Shinji
Published: November 2020

Polycyclic aromatic compounds consisting of four or five fused anthracene units were synthesized by PtCl2‐catalyzed cycloisomerization as novel long expanded helicenes. These compounds have helical structures with significant stacking of the terminal anthracene moieties at 0.33 nm interlayer distance. In the UV‐vis and fluorescence spectra, the absorption and emission bands were red‐shifted as the number of fused anthracene units was increased. The characteristic broad and long‐lived emission bands of the long analogues are explained by the excimer‐like stabilization of the excited state. These photophysical data as well as their cyclic voltammetric data are discussed on the basis of the π‐conjugation and interlayer π⋅⋅⋅π interactions in the molecular structures and the molecular orbitals. The barrier and mechanism of helical inversion are also reported.
Enantioseparation of ketoconazole and miconazole by capillary electrophoresis and a study on their inclusion interactions with β‐cyclodextrin and derivatives
Authors: Azhari Nurul Raihana , Yahaya Noorfatimah , Mohd Suah Faiz Bukhari M. , Prabu Samikannu , Yih Hui Boon , Shahriman Mohamad Shariff , Mohamad Zain Nur Nadhirah , Raoov Muggundha
Published: November 2020

A chiral separation method coupled with capillary electrophoresis (CE) analysis for ketoconazole and miconazole enantiomers using chiral selectors such as β‐cyclodextrin (β‐CD) and hydroxypropyl‐β‐CD (HP‐β‐CD) was developed in this study, which included the optimisation, validation and application of the method on the antifungal cream samples. The formation of inclusion complex between the hosts (β‐CD and HP‐β‐CD) and guests (ketoconazole and miconazole) were compared and analysed using ultraviolet–visible spectrophotometry, nuclear magnetic resonance (NMR) spectroscopy and molecular docking methods. Results from the study showed that in a concentration that ranged between 0.25 and 50 mg L−1, the linear calibration curves of each enantiomer had a high coefficient of regression (R2 > 0.999), low limit of detection (0.075 mg L−1) and low limit of quantification (0.25 mg L−1). The relative standard deviation (RSD) of the intraday and interday analyses ranged from 0.79% to 8.01% and 3.30% to 11.43%, respectively, while the recoveries ranged from 82.0% to 105.7% (RSD < 7%, n = 3). The most probable structure of the inclusion complexes was proposed based on the findings from the molecular docking studies conducted using the PatchDock server.
Overview of Innovative Technologies in Liquid‐Liquid Extraction Regarding Flexibility
Authors: Polyakova Maria , Diekmann Anna‐Lena , Grünewald Marcus
Published: November 2020

As a result of increasing market volatility and product diversification the technology requirements will change in the future. Flexibility needs to be increased, enabling a large operating window while maintaining intensive mass and energy transfer and resource‐efficiency. A promising approach is using innovative small‐scale technologies. To assess flexibility, the technologies must be characterized in a wide range of operating parameters and physical properties. Therefore, research work on innovative technologies for liquid‐liquid extraction is presented.
In Vivo Albumin‐Binding of a C‐Functionalized Cyclam Platform for 64Cu‐PET/CT Imaging in Breast Cancer Model
Authors: Le Bihan Thomas , Driver Cathryn H. S. , Ebenhan Thomas , Le Bris Nathalie , Zeevaart Jan Rijn , Tripier Raphaël
Published: November 2020

An improved glucose‐chelator‐albumin bioconjugate (GluCAB) derivative, GluCAB‐2Mal, has been synthesized and studied for in vivo 64Cu‐PET/CT imaging in breast cancer mice models together with its first‐generation analogue GluCAB‐1Mal. The radioligand works on the principle of tumor targeting through the enhanced permeability and retention (EPR) effect with a supportive role played by glucose metabolism. [64Cu]Cu‐GluCAB‐2Mal (99 % RCP) exhibited high serum stability with immediate binding to serum proteins. In vivo experiments for comparison between tumor targeting of [64Cu]Cu‐GluCAB‐2Mal and previous‐generation [64Cu]Cu‐GluCAB‐1Mal encompassed microPET/CT imaging and biodistribution analysis in an allograft E0771 breast cancer mouse model. Tumor uptake of [64Cu]Cu‐GluCAB‐2Mal was clearly evident with twice as much accumulation as compared to its predecessor and a tumor/muscle ratio of up to 5 after 24 h. Further comparison indicated a decrease in liver accumulation for [64Cu]Cu‐Glu‐CAB‐2Mal.
Pediatric hepatic cancer incidence and survival: 30‐year trends in Ontario, Canada; the United States; and Australia
Authors: Di Giuseppe Giancarlo , Youlden Danny R. , Aitken Joanne F. , Pole Jason D.
Published: November 2020

Background

Pediatric hepatic cancer is a rare malignancy, comprising only approximately 2% of all cancers diagnosed in children aged <15 years. The authors sought to describe trends in pediatric hepatic cancer incidence and survival in Ontario, Canada; the United States; and Australia.

Methods

Children aged <15 years who were diagnosed with hepatic cancer from 1985 through 2013 were ascertained through population‐based registries and followed from the time of diagnosis until December 31, 2015. Age‐standardized incidence and 5‐year relative survival were calculated for each jurisdiction. Multivariable flexible parametric survival models were used to explore predictors of hepatic cancer mortality.

Results

A total of 794 children were identified in Ontario (148 children), the United States (400 children), and Australia (246 children). The average annual incidence increased by 2.2% (95% CI, 0.5%‐4.0%) in Australia, 2.1% (95% CI, 0.9%‐3.3%) in the United States, and 1.3% (95% CI, ‐0.4% to 3.0%) in Ontario. The 5‐year relative survival rate improved from 60% to 82% (P = .08) in Ontario and 62% to 78% (P = .02) in the United States between the diagnostic periods 1985 through 1994 and 2005 through 2013, whereas in Australia the rate remained constant (between 74% and 77%) during the study period. On multivariable analysis, there was no significant difference noted with regard to the hazard of death between jurisdictions (P = .06). Older age, the presence of metastatic disease, and being diagnosed with hepatocellular carcinoma were found to be associated with mortality.

Conclusions

The incidence of hepatic cancer in children appears to have increased over the last 30 years in Australia and North America. Survival differences between Australia; Ontario, Canada; and the United States observed in the 1980s and 1990s were no longer apparent and only marginal geographical differences in the hazard of mortality were observed.
DNA‐Origami‐Based Assembly of Au@Ag Nanostar Dimer Nanoantennas for Label‐Free Sensing of Pyocyanin
Authors: Kaur Vishaldeep , Tanwar Swati , Kaur Gagandeep , Sen Tapasi
Published: November 2020

Early‐stage detection of diseases caused by pathogens is a prerequisite for expedient patient care. Due to the limited signal‐to‐noise ratio, molecular diagnostics needs molecular signal amplification after recognition of the target molecule. In this present study, we demonstrate the design of plasmonically coupled bimetallic Ag coated Au nanostar dimers with controlled nanogap using rectangular DNA origami. We further report the utility of the designed nanostar dimer structures as efficient SERS substrate for the ultrasensitive and label‐free detection of the pyocyanin molecule, which is a biomarker of the opportunistic pathogenic bacteria, Pseudomonas aeruginosa. The experimental results showed that the detection limit of pyocyanin with such nanoantenna based biosensor was 335 pM, which is much lower than the clinical range of detection. Thus, fast, sensitive and label‐free detection of pyocyanin at ultralow concentration in an infected human body can pave a facile route for early stage warning for severe bacterial infections.
Structural and Photophysical Properties of Various Polypyridyl Ligands: A Combined Experimental and Computational Study
Authors: De Bruecker Liesbeth , Everaert Jonas , Van Der Voort Pascal , Stevens Christian V. , Waroquier Michel , Van Speybroeck Veronique
Published: November 2020

The front cover artwork is provided by the groups of Prof. Veronique Van Speybroeck, Prof. Pascal Van Der Voort and Prof. Christian V. Stevens (Ghent University, Belgium). The image shows the interaction between visible light and the building blocks of covalent triazine frameworks, which are promising heterogeneous catalysts. Read the full text of the Article at 10.1002/cphc.202000592.
Assessment of corporate social responsibility by addressing sustainable development goals
Authors: Lu Jintao , Liang Mengshang , Zhang Chong , Rong Dan , Guan Hailing , Mazeikaite Kristina , Streimikis Justas
Published: November 2020

The aim of this study is to discuss the issues relevant to the CSR evaluation and to develop a model of CSR assessment by taking into account SDGs. Based on a critical literature review, the advantages and limits of CSR assessment models were analyzed with the SDGs addressed, and the framework of a novel model of CSR assessment was proposed in this study. The main limitations of CSR in addressing SDGs were defined as follows: the selective implementation of SDGs, greenwashing, the lack of the integration of the stakeholders, the lack of incorporation of SMEs, and the difference in CSR practices among countries. The created model includes all SDGs involved. Moreover, the positive and negative effects of CSR on SDGs were addressed. This proposed CSR assessment model can help to solve the major problems described above: selective implementation of SDGs, greenwashing, and the inability to compare CSR among industries or countries.
Metabolic dysfunction in pregnancy: Fingerprinting the maternal metabolome using proton nuclear magnetic resonance spectroscopy
Authors: Scott Hannah D. , Buchan Marrissa , Chadwick Caylin , Field Catherine J. , Letourneau Nicole , Montina Tony , Leung Brenda M. Y. , Metz Gerlinde A. S.
Published: November 2020

Aims

Maternal metabolic disorders place the mother at risk for negative pregnancy outcomes with potentially long‐term health impacts for the child. Metabolic syndrome, a cluster of features associated with increased risk of metabolic disorders, such as cardiovascular disease, diabetes and stroke, affects roughly one in five Canadians. Metabolomics is a relatively new technique that may be a useful tool to identify women at risk of metabolic disorders. This study set out to characterize urinary metabolic biomarkers of pregnant women with obesity and of pregnant women who later developed gestational diabetes mellitus (pre‐GDM), compared to controls.

Methods and Materials

Second trimester urine samples were collected through the Alberta Pregnancy Outcomes and Nutrition (APrON) cohort and examined with 1H nuclear magnetic resonance (NMR) spectroscopy. Multivariate analysis was used to examine group differences, and machine learning feature selection tools identified the metabolites contributing to separation.

Results

Obesity and pre‐GDM metabolomes were distinct from controls and from each other. In each comparison, the glycine, serine and threonine pathways were the most impacted. Pantothenate, formic acid and glycine were downregulated by obesity, while formic acid, dimethylamine and galactose were downregulated in pre‐GDM. The three most impacted metabolites for the comparison of obesity versus pre‐GDM groups were upregulated creatine/caffeine, downregulated sarcosine/dimethylamine and upregulated maltose/sucrose in individuals who later developed GDM.

Conclusion

These findings suggest a role for urinary metabolomics in the prediction of GDM and metabolic marker identification for potential diagnostics and prognostics in women at risk.
A compact inverted Y‐shaped circularly polarized wideband monopole antenna with open loop
Authors: Dhara Reshmi , Kundu Taraknath
Published: November 2020

This article presents a novel, compact, single feed circularly polarized (CP) microstrip antenna. Proposed design involve an inverted Y‐shaped radiating patch fed by an L‐shaped microstrip line feed and a rectangular open‐loop placed near its right corner. A semi‐rectangular ground plane is used on the opposite side of the substrate. Coupling between the rectangular open‐loop and the inverted Y‐shaped patch plays a vital role in attaining wideband CP, while the semi‐rectangular ground plane is crucial for enhancing impedance bandwidth (IBW). The optimized design achieved measured wide IBW of 5.164 GHz (65.53%, spanning over 5.297‐10.461 GHz) having its center frequency (frc) at 7.878 GHz. The corresponding measured axial ratio bandwidth (ARBW) obtained inside the measured IBW curve is 2.25 GHz (having its center CP resonating frequency fcp 7.52 GHz, spanning over 6.40‐8.65 GHz, 29.92%). Measurement results are validated in both Ansys Electronics Desktop 2020 R1 and CST Microwave Studio 2018. Proposed antenna is fabricated on FR‐4 epoxy substrate of 1.6 mm thickness and exhibits a very small footprint of just 400 mm2 (20 × 20 mm2) (size 0.58λmgL × 0.58λmgL × 0.046λmgL, where λmgL is the measured guided wavelength at lower resonating frequency fmrL = 5.297 GHz) with 51.31% reduction in size. Measured maximum peak gain for the impedance band is 2.04 dBi at 8.8 GHz and 1.96 dBi at fcp 7.52 GHz. The structure of the proposed antenna is extremely simple, quite small in size and its CP bands can be suitable for some C‐band and ITU (International Telecommunication Union)—8 GHz application.
AHNS endocrine surgery section consensus statement on nasopharyngolaryngoscopy and clinic reopening during COVID‐19: How to get back to optimal safe care
Authors: Bleier Benjamin , Workman Alan , Burks Ciersten , Maxfield Alice , Stack Brendan C. , Nathan Cherie‐Ann , McCammon Susan , Varvares Mark , Schmalbach Cecelia , Wang Steven , Califano Joseph , Shnayder Yelizaveta , Gillespie Marion B. , Enepekides Danny , Witterick Ian , El‐Sayed Ivan , Lin Derrick , Patel Urjeet , Kraus Dennis , Randolph Gregory
Published: November 2020

This article provides best practice guidelines regarding nasopharyngolaryngoscopy and OHNS clinic reopening during the COVID‐19 pandemic. The aim is to provide evidence‐based recommendations defining the risks of COVID‐19 in clinic, the importance of pre‐visit screening in addition to testing, along with ways to adhere to CDC guidelines for environmental, source, and engineering controls.
Epigenetic regulation of cancer stem cell formation and maintenance
Authors: French Rhiannon , Pauklin Siim
Published: November 2020

Cancerous tumours contain a rare subset of cells with stem‐like properties that are termed cancer stem cells (CSCs). CSCs are defined by their ability to divide both symmetrically and asymmetrically, to initiate new tumour growth and to tolerate the foreign niches required for metastatic dissemination. Accumulating evidence suggests that tumours arise from cells with stem‐like properties, the generation of CSCs is therefore likely to be an initiatory event in carcinogenesis. Furthermore, CSCs in established tumours exist in a dynamic and plastic state, with nonstem tumour cells thought to be capable of de‐differentiation to CSCs. The regulation of the CSC state both during tumour initiation and within established tumours is a desirable therapeutic target and is mediated by epigenetic factors. In this review, we will explore the epigenetic parallels between induced pluripotency and the generation of CSCs, and discuss how the epigenetic regulation of CSCs opens up novel opportunities for therapeutic intervention.
Program organization rather than choice of test determines success of cervical cancer screening: Case studies from Bangladesh and India
Authors: Bhatla Neerja , Nessa Ashrafun , Oswal Kunal , Vashist Shachi , Sebastian Paul , Basu Partha
Published: November 2020

The call for elimination of cervical cancer as a public health problem by the World Health Organization has led to intense focus on the burden of disease, available resources, and the possibility of introducing efficient systems for screening and treatment that allow effective cancer control in limited‐resource settings. Presently, the focus is on the introduction of rapid, technologically less‐demanding, affordable HPV testing. However, until such tests become widely available, the momentum that has been gained using visual inspection with acetic acid (VIA) should not be lost. Countries with limited resources and a heavy burden of cervical cancer, such as Bangladesh and India, introduced and scaled up VIA‐based programs with varying degrees of programmatic organization and performance. Despite its limitations, VIA’s simplicity and affordability has allowed these countries to build infrastructure, increase numbers of trained healthcare personnel, and develop a system of multilevel coordination within the health system. Such efforts will have long‐term advantages provided that countries have access to an appropriate HPV test and build on their efforts to improve program organization through a strengthened health system, translating lessons learned in program implementation, logistics, and compliance with the new paradigm.
Anti‐VEGF‐R2 Aptamer and RGD Peptide Synergize in a Bifunctional Hydrogel for Enhanced Angiogenic Potential
Authors: Roy Tanaya , James Bryan D. , Allen Josephine B.
Published: November 2020

Hydrogels have gained interest for use in tissue regeneration and wound healing because of their absorbing and swelling properties as well as their ability to mimic the natural extracellular matrix. Their use in wound healing specifically may be in the form of a patch or wound dressing or they may be administered within the wound bed as a filler, gel in situ, to promote healing. Thiolated hyaluronic acid‐polyethylene diacrylate (tHA‐PEGDA) hydrogels are ideal for this purpose due to their short gelation times at physiological temperature and pH. But these hydrogels alone are not enough and require added components to gain bioactivity. In this work, RGD adhesion peptides and an antivascular endothelial growth factor receptor‐2 (VEGF‐R2) DNA aptamer are incorporated into a tHA‐PEGDA hydrogel to make a bifunctional hyaluronic acid hydrogel. RGD peptides promote attachment and growth of cells while the anti‐VEGF‐R2 DNA aptamer seems to improve cell viability, induce cell migration, and spur the onset of angiogenesis by tube formation by endothelial cells. This bifunctional hydrogel supports cell culture and has improved biological properties. The data suggest that these hydrogels can be used for advanced tissue regeneration applications such as in wound healing.
A Flexible Polymer Nanofiber‐Gold Nanoparticle Composite Film for Solar‐Thermal Seawater Desalination
Authors: Mu Shilin , Nan Jingjie , Shi Chenyu , Tang Xiaoduo , Liu Shuwei , Chen Hongxu , Zhang Junhu , Yang Bai
Published: November 2020

Interfacial solar‐thermal conversion has broad application prospects in solar driven steam generation, seawater desalination, sewage purification, and other fields. For a wide range of applications, high‐efficiency interfacial solar‐thermal conversion materials with the feature of being lightweight, flexible, and easy to scale up at the same time are significantly valued. Herein, a strategy for the preparation of solar‐thermal poly (4‐vinylpyridine) (P4VP) nanofiber‐gold nanoparticle (Au NP) composite film (PGCF) is reported. Combining with the flexible and lightweight P4VP nanofibers, these absorbed Au NPs enable better solar‐thermal conversion efficiency. Accordingly, the PGCF provides high‐performance interfacial solar‐driven steam generation, with 77% solar‐heat conversion efficiency under the power density of 3.4 kW m−2, which shows stable output (3.4 kg m−2 h−1) in the application of solar‐driven seawater desalination. In addition, PGCF is light in weight, flexible, and suitable for scalable commercial production, enabling PGCF broad application prospects in the field of light‐to‐heat conversion.
A diffusion model for backfill grout behind shield tunnel lining
Authors: Liu Xiao‐Xue , Shen Shui‐Long , Xu Ye‐Shuang , Zhou Annan
Published: November 2020

This paper presents an analytical model to investigate backfill grout diffusion behind tunnel segmental lining, in which the backfill grout is taken as a Bingham fluid. The analytical model of grout diffusion is derived based on force–equilibrium principle, Darcy's law, and the law of momentum conservation of the grout. Time‐dependent grout diffusion pressure and distance are highlighted in the model. The proposed grout diffusion model is applied in two field cases: Metro Lines No. 9 and No. 4 in Shanghai City. The results show that the proposed model agrees well with the measured grout diffusion distance in the field. Parametric studies are then conducted, implying that grout diffusion distance along the radial direction of tunnel lining is proportional to either hydraulic conductivity or initial grout pressure, whereas it is in inverse proportion to the yield stress of backfill grout. The distributions of initial grout pressure exert key influences on the grout diffusion distance and grout diffusion pressure behind tunnel segment lining.
Ultra‐high‐field MRI using composite RF (STEP) pulses
Authors: Ordidge Roger , Cleary Jon , Glarin Rebecca , Blunck Yasmin , Farquharson Shawna , Moffat Bradford
Published: November 2020

Ultra‐high field MRI offers many opportunities to expand the applications of MRI. In order for this to be realized, the technical problems associated with MRI at field strengths of 7 T and greater need to be solved or mitigated. This paper explores the use of new variations of composite RF pulses, named serial transmit excitation pulses (STEP), in contrast to parallel pulse techniques, in order to remove and/or mitigate the effects of non‐uniform B1 excitation fields associated with the subject (eg the human brain). Several techniques based on STEP sequences are introduced and their application to human brain imaging is presented and evaluated.
Robust topology optimization based on finite strain considering uncertain loading conditions
Authors: Nishino Takayuki , Kato Junji
Published: November 2020

The present study proposes a method of robust topology optimization assuming uncertainties in the magnitude and direction of loads applied to a geometrically nonlinear structure. The objective function is the sum of the expected value and the standard deviation of end‐compliance of a structure with a compressible Neo‐Hookean hyperelasticity. In this study, quadratic approximation of the end‐compliance with respect to random variables is employed to reduce computational cost. To ensure its accuracy, a complete analytical formulation is derived, and the performance and limitation of the proposed method are deeply discussed. The performance of the proposed method is verified and its numerical examples emphasize the importance of considering geometrical nonlinearity to obtain robust structures with respect to uncertainties of loading conditions. Finally, we have obtained a finding that the optimized network system consisting of thin members plays a significant role in the improvement of robustness of structures.
More Insights on the Use of γ-Secretase Inhibitors in Cancer Treatment
Authors: López-Nieva Pilar , González-Sánchez Laura , Cobos-Fernández María Ángeles , Córdoba Raúl , Santos Javier , Fernández-Piqueras José
Published: November 2020

The NOTCH1 gene encodes a transmembrane receptor protein with activating mutations observed in many T-cell acute lymphoblastic leukemias (T-ALLs) and lymphomas, as well as in other tumor types, which has led to interest in inhibiting NOTCH1 signaling as a therapeutic target in cancer. Several classes of Notch inhibitors have been developed, including monoclonal antibodies against NOTCH receptors or ligands, decoys, blocking peptides, and γ-secretase inhibitors (GSIs). GSIs block a critical proteolytic step in NOTCH activation and are the most widely studied. Current treatments with GSIs have not successfully passed clinical trials because of side effects that limit the maximum tolerable dose. Multiple γ-secretase–cleavage substrates may be involved in carcinogenesis, indicating that there may be other targets for GSIs. Resistance mechanisms may include PTEN inactivation, mutations involving FBXW7, or constitutive MYC expression conferring independence from NOTCH1 inactivation. Recent studies have suggested that selective targeting γ-secretase may offer an improved efficacy and toxicity profile over the effects caused by broad-spectrum GSIs. Understanding the mechanism of GSI-induced cell death and the ability to accurately identify patients based on the activity of the pathway will improve the response to GSI and support further investigation of such compounds for the rational design of anti-NOTCH1 therapies for the treatment of T-ALL.

Implications for Practice

γ-secretase has been proposed as a therapeutic target in numerous human conditions, including cancer. A better understanding of the structure and function of the γ-secretase inhibitor (GSI) would help to develop safe and effective γ-secretase–based therapies. The ability to accurately identify patients based on the activity of the pathway could improve the response to GSI therapy for the treatment of cancer. Toward these ends, this study focused on γ-secretase inhibitors as a potential therapeutic target for the design of anti-NOTCH1 therapies for the treatment of T-cell acute lymphoblastic leukemias and lymphomas.
The emergence of new knowledge: The case of zero‐reference patents
Authors: Chen Tian , Kim Changhyun , Miceli Kevin A.
Published: November 2020

Research Summary

Knowledge‐based theories have posited that new technologies are recombinations of prior technologies. To bring about new innovations, inventors usually use past known knowledge as a key ingredient. However, there exists a particular type of new technology that does not have any explicit prior technology predecessors. These pioneering technologies, also referred to as “zero‐reference patents,” not only reflect new knowledge but can also serve as the initial seed from which recombination can subsequently create more knowledge and technologies. We seek to understand the characteristics of the inventors who create these pioneering technologies. We find that having focused, specific expertise is more important than a broad knowledge base in the development of these pioneering technologies, and that prior inventive success can hinder their creation.

Managerial Summary

We highlight a type of patents which have zero backward references, representing a form of pioneering knowledge. Unlike other types of knowledge, pioneering knowledge comes from inventors who have less successful but more focused experience. Although the zero‐reference patents generally fail to show usefulness on their own, the patents which build upon zero‐reference patents are more likely to become breakthrough patents and to generate a high number of forward citations. Zero‐reference patents are the seeds for future breakthroughs. Given the importance of breakthroughs, we offer an alternative path toward creating such knowledge. Our analysis at the level of inventors also gives guidance on the type of talent who are more likely to generate pioneering knowledge.
Gel Polymer Electrolyte with Enhanced Performance Based on Lignocellulose Modified by NaOH/Urea for Lithium‐Sulfur Batteries
Authors: Huang W. , Li Y. , Gu H. , Wang J. , Zhong Q.
Published: November 2020

An environmentally friendly gel polymer electrolyte (GPE) applied in lithium‐sulfur (Li−S) batteries is based on the modified lignocellulose (LC), which is made from raw LC material with NaOH/urea aqueous solution through a simple partial dissolution method. Surfaces of fibers dissolve during the dissolution process and form a matrix among the fibers during the regeneration stage, which significantly improves the mechanical properties by up to five times. Meanwhile, the GPE (G3) shows enough liquid electrolyte absorption (144 %) and good thermal stability when the dissolution time is 20 min. It has high lithium ion transference number of 0.74 and good ion conductivity of 2.42 mS cm−1, which is an order higher than that of the commercial separator. Besides, sufficient electrochemical stability and interface compatibility can meet requirements of Li−S batteries. Compared with the battery with the commercial separator, Li/G3/S battery exhibits enhanced rate and cycling performance, which shows that G3 can effectively suppress the “shuttle effect”.