bluuebunny/crossref_metadata_2025 huggingface dataset:
A Pumpless Microfluidic Neonatal Lung Assist Device for Support of Preterm Neonates in Respiratory Distress
Authors: Dabaghi Mohammadhossein , Rochow Niels , Saraei Neda , Fusch Gerhard , Monkman Shelley , Da Kevin , Shahin‐Shamsabadi Alireza , Brash John L. , Predescu Dragos , Delaney Kathleen , Fusch Christoph , Selvaganapathy P. Ravi
Published: September 2020

Premature neonates suffer from respiratory morbidity as their lungs are immature, and current supportive treatment such as mechanical ventilation or extracorporeal membrane oxygenation causes iatrogenic injuries. A non‐invasive and biomimetic concept known as the “artificial placenta” (AP) would be beneficial to overcome complications associated with the current respiratory support of preterm infants. Here, a pumpless oxygenator connected to the systemic circulation supports the lung function to relieve respiratory distress. In this paper, the first successful operation of a microfluidic, artificial placenta type neonatal lung assist device (LAD) on a newborn piglet model, which is the closest representation of preterm human infants, is demonstrated. This LAD has high oxygenation capability in both pure oxygen and room air as the sweep gas. The respiratory distress that the newborn piglet is put under during experimentation, repeatedly and over a significant duration of time, is able to be relieved. These findings indicate that this LAD has a potential application as a biomimetic artificial placenta to support the respiratory needs of preterm neonates.
Mass concentration and size distribution of particles released from harvesting and biomass burning of sugarcane
Authors: Dattamudi Sanku , Wang Jim J. , Dodla Syam K. , DeLaune Ronald , Hiscox April , Viator Howard , Jeong Changyoon
Published: September 2020

We evaluated size distribution and mass concentrations of fine (particulate matter < 2.5 μm, PM2.5) and coarse (particulate matter = 2.5–10 μm, PM2.5‐10) particles released during sugarcane (Saccharum spp.) harvesting operations, including cutting of green cane (GH), burning of standing cane (SB), cane harvest cutting after SB (BH), and ground burning of harvest residues left in the field (GB). Total number of PM2.5 released from GB was 1.63 times greater than that from SB. Total time of burning (flaming + smoldering) phase during GB was 1.5 to 2.1 times longer than SB. The flaming phase for both GB and SB was shorter than the smoldering phase but emitted 5.2 to 7.5 times more PM2.5. Average particle density of PM2.5 from burning operations was 1.12 g cm−3 for GB and 0.52 g cm−3 for SB. The GH and BH released lower PM2.5 but higher PM2.5‐10 as compared to SB and GB. Overall, biomass burning, regardless GB and SB difference, released significantly higher PM2.5 than harvest‐cutting operations.
Rechargeable Mild Aqueous Zinc Batteries for Grid Storage
Authors: Yan Mengdie , Ni Hailan , Pan Huilin
Published: September 2020

Rechargeable mild aqueous zinc batteries have recently attracted tremendous interest for large‐scale grid storage due to their potentially highest energy density and safety, and lowest cost among available aqueous battery technologies. Herein, a variety of cathode materials, zinc anode structures, and electrolytes are briefly reviewed. A multi‐type of charge carriers such as Zn2+, H+, and anions can be reversibly stored in cathodes in rechargeable mild aqueous zinc batteries. The charge storage behavior in cathodes and strategies to address the reversibility and dendrite growth of zinc anodes are comprehensively summarized. Solutions to the remaining challenges such as long‐term stability and economy of cathodes and zinc anodes are discussed. This review also includes an analysis of mild aqueous zinc battery chemistry with reported cathode materials and anode materials. A perspective for the practical development of rechargeable mild aqueous zinc batteries regarding cathode design, zinc anode utilization, and cell configuration is also included to accelerate the commercialization of zinc batteries. In the future, rechargeable mild aqueous zinc batteries would be a visible energy storage solution for grid storage.
Enhancing Photostability of a Coumarin Dye by Self‐inclusion into a Cyclodextrin Cavity in Aqueous Solution and Living Cells
Authors: Shigemitsu Hajime , Matsuda Keigo , Mori Tadashi , Nakatsuji Hirotaka , Matsusaki Michiya , Kida Toshiyuki
Published: September 2020

Photostable organic dyes are highly demanded for longtime or super‐resolution bioimaging. Herein, we demonstrate effective improvement of photostability of a coumarin dye (Pacific Blue (PB)) by steric protection using a cyclodextrin. The PB conjugated cyclodextrin (PB−CD) showed 2.8 times higher photostability than PB ethyl amide (PB−EA) which is a comparative compound in vitro. The cyclodextrin conjugation to PB not only protect PB unit from reactive chemicals, but also suppress reactive oxygen species (ROS) generation which causes dye degradation. The effects afford significant improvement of photostability of PB dye. Finally, the photostability of PB−CD was evaluated using confocal laser scanning microscopy (CLSM) and the significant improvement effect was proofed even in living cells.
Genetic variability of the sws1 cone opsin gene among New World monkeys
Authors: Mantovani Viviani , Hauzman Einat , Corredor Vitor H. , Goulart Paulo R. K. , Galvão Olavo , Talebi Mauricio , Pessoa Daniel M. A. , Soares Juliana G. M. , Fiorani Mario , Gattass Ricardo , Fix Ventura Dora , Bonci Daniela M. O.
Published: September 2020

Vision is a major sense for Primates and the ability to perceive colors has great importance for the species ecology and behavior. Visual processing begins with the activation of the visual opsins in the retina, and the spectral absorption peaks are highly variable among species. In most Primates, LWS/MWS opsins are responsible for sensitivity to long/middle wavelengths within the visible light spectrum, and SWS1 opsins provide sensitivity to short wavelengths, in the violet region of the spectrum. In this study, we aimed to investigate the genetic variation on the sws1 opsin gene of New World monkeys (NWM) and search for amino acid substitutions that might be associated with the different color vision phenotypes described for a few species. We sequenced the exon 1 of the sws1 opsin gene of seven species from the families Callitrichidae, Cebidae, and Atelidae, and searched for variation at the spectral tuning sites 46, 49, 52, 86, 90, 93, 114, 116, and 118. Among the known spectral tuning sites, only residue 114 was variable. To investigate whether other residues have a functional role in the SWS1 absorption peak, we performed computational modeling of wild‐type SWS1 and mutants A50I and A50V, found naturally among the species investigated. Although in silico analysis did not show any visible effect caused by these substitutions, it is possible that interactions of residue 50 with other sites might have some effect in the spectral shifts in the order of ~14 nm, found among the NWM. We also performed phylogenetic reconstruction of the sws1 gene, which partially recovered the species phylogeny. Further studies will be important to uncover the mutations responsible for the phenotypic variability of the SWS1 of NWM, and how spectral tuning may be associated with specific ecological features such as preferred food items and habitat use.
Ein gemischtes, schwereres Si=Ge Analogon eines Vinylanions
Authors: Majhi Paresh Kumar , Huch Volker , Scheschkewitz David
Published: September 2020

Die vielseitigen Reaktivitäten von Disileniden und Digermenid, schwereren Analoga von Vinylanionen, haben den Pool an Silicium‐ und Germaniumverbindungen in den letzten zwei Jahrzehnten mit verschiedensten unerwarteten Strukturmotiven erheblich erweitert. Wir berichten nun über die Synthese eines cyclischen, heteronuklearen Vinylanionanalogons mit einer Si=Ge Bindung, dem Kaliumsilagermenid als stabiles THF‐ und 18‐c‐6‐Solvat durch KC8Reduktion von Germylen‐ oder Digermenvorläufern. Seine Eignung als Baustein für die Synthese von funktionellen Silagermenen wird durch die jeweiligen Reaktionen mit Chlorsilan und Chlorphosphan unter Bildung der entsprechenden Silyl‐ und Phosphanylsilagermenen nachgewiesen. Röntgenkristallographische Analyse, UV/Vis Spektroskopie und DFT Berechnungen zeigten einen erheblichen Grad an π‐Konjugation zwischen N=C und Si=Ge Doppelbindungen in der Titelverbindung.
A General Strategy to Control Viscosity Sensitivity of Molecular Rotor‐Based Fluorophores
Authors: Ye Songtao , Zhang Han , Fei Jinyu , Wolstenholme Charles H. , Zhang Xin
Published: September 2020

Molecular rotor‐based fluorophores (RBFs) have been widely used in many fields. However, the lack of control of their viscosity sensitivity limits their application. Herein, this problem is resolved by chemically installing extended π‐rich alternating carbon‐carbon linkages between the rotational electron donors and acceptors of RBFs. The data reveal that the length of the linkage strongly influences the viscosity sensitivity, likely resulting from varying height of the energy barriers between the fluorescent planar and the dark twisted configurations. Three RBF derivatives that span a wide range of viscosity sensitivities were designed. These RBFs demonstrated, through a dual‐color imaging strategy, that they can differentiate misfolded protein oligomers and insoluble aggregates, both in test tubes and live cells. Beyond RBFs, it is envisioned that this chemical mechanism might be generally applicable to a wide range of photoisomerizable and aggregation‐induced emission fluorophores.
Bimetallic, Silylene‐Mediated Multielectron Reductions of Carbon Dioxide and Ethylene
Authors: Whited Matthew T. , Zhang Jia , Conley Anna M. , Ma Senjie , Janzen Daron E. , Kohen Daniela
Published: September 2020

A metal/ligand cooperative approach to the reduction of small molecules by metal silylene complexes (R2Si=M) is demonstrated, whereby silicon activates the incoming substrate and mediates net two‐electron transformations by one‐electron redox processes at two metal centers. An appropriately tuned cationic pincer cobalt(I) complex, featuring a central silylene donor, reacts with CO2 to afford a bimetallic siloxane, featuring two CoII centers, with liberation of CO; reaction of the silylene complex with ethylene yields a similar bimetallic product with an ethylene bridge. Experimental and computational studies suggest a plausible mechanism proceeding by [2+2] cycloaddition to the silylene complex, which is quite sensitive to the steric environment. The CoII/CoII products are reactive to oxidation and reduction. Taken together, these findings demonstrate a strategy for metal/ligand cooperative small‐molecule activation that is well‐suited to 3d metals.
Polyurethanes from Direct Organocatalytic Copolymerization of p‐Tosyl Isocyanate with Epoxides
Authors: Jia Mingchen , Hadjichristidis Nikos , Gnanou Yves , Feng Xiaoshuang
Published: September 2020

The direct copolymerization of p‐tosyl isocyanate (TSI) with epoxides, initiated by onium salts in the presence of trialkylborane, to produce polyurethanes is reported. The rate of copolymerization and the (regio)selectivity were investigated in relation to the trialkylborane and the initiator used. Under optimized conditions such copolymerizations have been successfully performed for a wide range of epoxides, including ethylene oxide, propylene oxide, 1‐octene oxide, cyclohexene oxide, and allyl glycidyl ether. These copolymerizations afford a new category of polyurethanes, clear of side products such as cyclic oxazolidinone, isocyanurate, and poly(isocyanate) linkages. The experimental conditions used in this work are compatible with those for the organocatalytic (co)polymerization of other oxygenated monomers and CO2, holding the potential for their terpolymerization with p‐tosyl isocyanate and the development of new materials with unprecedented properties.
Elektrochemische B‐H‐Nitrogenierung: Zugang zu Aminosäure‐ und BODIPY‐markierten nido‐Carboranen
Authors: Yang Long , Bongsuiru Jei Becky , Scheremetjew Alexej , Kuniyil Rositha , Ackermann Lutz
Published: September 2020

Es wurden elektrokatalysierte oxidative B‐H‐Nitrogenierungen von nido‐Carboran (nido‐7,8‐C2B9H12−) mit N‐Heterocyclen etabliert, welche die Herstellung verschiedener N‐substituierter nido‐Carborane ohne chemische Oxidationsmittel oder Metallkatalysator unter Umgebungsbedingungen ermöglichen. Die vielfältigen Elektrolysen erfolgten mit hoher Effizienz sowie Chemo‐ und Positionsselektivität, wobei Elektrizität als nachhaltiges und einziges Oxidationsmittel verwendet wurde. Diese Strategie schuf die Voraussetzungen für einen benutzerfreundlichen Zugang zu neuartigen, mit Aminosäuren und fluorogenem Bordipyrromethen (BODIPY) markierten nido‐Carboran‐Hybriden.
Strong Fermi Resonance Associated with Proton Motions Revealed by Vibrational Spectra of Asymmetric Proton‐Bound Dimers
Authors: Huang Qian‐Rui , Shishido Ryunosuke , Lin Chih‐Kai , Tsai Chen‐Wei , Tan Jake A. , Fujii Asuka , Kuo Jer‐Lai
Published: September 2020

Infrared spectra for a series of asymmetric proton‐bound dimers with protonated trimethylamine (TMA‐H+) as the proton donor were recorded and analyzed. The frequency of the N–H+ stretching mode is expected to red shift as the proton affinity of proton acceptors increases. The observed band, however, shows a peculiar splitting of approximately 300 cm−1 with the intensity shifting pattern resembling a two‐level system. Theoretical investigation reveals that the observed band splitting and its extraordinarily large gap of around 300 cm−1 is a result of strong coupling between the fundamental of the proton stretching mode and overtone states of the two proton bending modes, that is commonly known as Fermi resonance (FR). We also provide a general theoretical model to link the strong FR coupling to the quasi‐two‐level system. Since the model does not depend on the molecular specification of TMA‐H+, the strong coupling we observed is an intrinsic property associated with proton motions.
An original experimental approach showing that most nonlinearities expressed by filled elastomers relate to microscopic friction and cavitation
Authors: Picquart Marion , Poirey Gilles , Puel Guillaume , Aubry Denis
Published: September 2020

Filled elastomers present a highly nonlinear behavior when submitted to cyclic mechanical loads. Origins of these nonlinearities are still uncertain, but many models rely on micromechanisms such as friction or cavitation at the filler/binder interface. To substantiate these hypotheses, an experimental approach is proposed to assess the real effects of friction and cavitation on the macroscopic response of filled elastomers. A linear, viscoelastic, transparent material is used to create macroscopic samples in which mechanisms are activated, separately or jointly. The response of these samples to cyclic mechanical loads shows that each mechanism generates some typical nonlinearities. A deeper analysis of the resulting curves allows a correlation between the nonlinearities characteristics (shapes and amplitudes) and the ones expressed by filled elastomers, providing clues for the development of future models.
Shining Light on C−S Bonds: Recent Advances in C−C Bond Formation Reactions via C−S Bond Cleavage under Photoredox Catalysis
Authors: Gao Jian , Feng Jie , Du Ding
Published: September 2020

In recent years, photoredox catalysis has been proved to be a significant and powerful strategy for the activation and the formation of different chemical bonds. In a general sense, these approaches rely on the generation of different active radical species enabled by light from various radical precursors via the cleavage of the corresponding chemical bonds, like C−H bond, C−N bond, C−O bond, C−C bond, C‐halo bond, C−S bond and other C‐heteroatom bonds. At the same time, these generated active radical intermediates can be used for the construction of various new chemical bonds. In this review, we highlight the generation of variousC‐centered radicals through the cleavage of C−S bonds enabled by light and their application in the construction of C−C bonds via generally radical pathways. A range of different substrates containing C−S bonds are discussed in this overview to expedite the progress of C−S bond activation and its subsequent functionalization under photoredox catalysis.
H258R mutation in KCNAB3 gene in a family with genetic epilepsy and febrile seizures plus
Authors: Ding Jian , Miao Qin‐Fei , Zhang Jing‐Wen , Guo Yu‐Xiong , Zhang Yu‐Xin , Zhai Qiong‐Xiang , Chen Zhi‐Hong
Published: September 2020

Purpose

The aim of this was to discover disease‐causing gene mutations linked to genetic epilepsy with febrile seizures plus (GEFS+) in a family in the Southern Chinese Han population. Of a three‐generation pedigree of 18 members in this family, 4 were affected with GEFS+.

Method

Blood samples of 7 family members—3 affected and 4 unaffected individuals—were collected. Whole‐exome sequencing was performed to assess for genetic mutations in two of the affected individuals and two of the unaffected individuals.

Results

Fourteen potentially consequential mutations were found in the two affected individuals and were validated with the Sanger sequencing method. Blood DNA tested in polymerase chain reaction with KCNAB3 primers revealed that one novel missense mutation, c.773A>G (p.H258R) in the KCNAB3 gene, which encoded the potassium voltage‐gated channel subfamily A regulatory β subunit 3 (KCNAB3), was shared by all three affected and one unaffected family member. However, this mutation did not appear in 300 unrelated control subjects. According to the bioinformatics tools SIFT and PROVEAN, p.H258R was thought to affect protein function. Functional verification showed that the KCNAB3 mutation could accelerate the inactivation of potassium channels, thus inhibiting potassium current, increasing neuronal excitability, and promoting epileptic convulsion.

Conclusions

These results reveal that mutations in the KCNAB3 gene may be associated with GEFS+.
Clinical utility of Epstein‐Barr virus DNA and other liquid biopsy markers in nasopharyngeal carcinoma
Authors: Tan Rong , Phua Sean Kean Ann , Soong Yoke Lim , Oon Lynette Lin Ean , Chan Kian Sing , Lucky Sasidharan Swarnalatha , Mong Jamie , Tan Min Han , Lim Chwee Ming
Published: September 2020

Nasopharyngeal carcinoma (NPC) is a malignant epithelial tumor ubiquitously associated with the Epstein‐Barr virus (EBV), which is highly prevalent in South China, Southeast Asia, and North Africa. Despite being a highly radio‐sensitive and treatable cancer, a majority of NPC patients are diagnosed in their advanced stage, and locoregional and distant relapses following definitive treatment contribute largely to cancer‐specific mortality among these patients. Given that EBV‐driven NPC is the predominant variant seen in endemic regions, various EBV detection methods have been developed and are utilized in screening, prognostication, and post‐treatment surveillance of NPC patients. While the Immunoglobulin A (IgA) serology assay is the most extensively studied EBV detection method, the detection of plasma EBV DNA released during replication or cellular apoptosis has shown superior outcomes in endemic population screening, prognostication, and detection of distant relapse. Furthermore, there is emerging evidence on the use of circulating tumor cells, microRNAs, DNA hypermethylation, and combination assays in various clinical scenarios. Herein, this paper provides a comprehensive overview of the relevant studies using various EBV detection techniques in the management of NPC. Specifically, the recent advances, clinical evidence, and challenges associated with the clinical application of EBV liquid biopsies in population screening, prognostication, and surveillance of NPC are presented.
Development of a remote laboratory for an electronic circuit design and analysis course with increased accessibility by using speech recognition technology
Authors: Yayla Ayse , Korkmaz Hayriye , Buldu Ali , Sarikas Ali
Published: September 2020

When the curricula of engineering undergraduate programs are examined, it can be seen that experimentation plays a very important role and the learning outcomes of the courses are mostly dependent on practical abilities. However, there may be a few who cannot use their hands permanently or temporarily among the students who are attending these courses. Therefore, the participation of disabled students in this part of the course has always been a problem. In this paper, a remote laboratory application that aims to increase the accessibility of electronic circuit design and analysis courses by using speech recognition technology is introduced. This laboratory is designed for hands‐free operation and enables students to analyze the electronic circuits by speaking. Google Web Speech API was used for speech recognition and the user interface was designed using Adobe Flash Professional. The parameters are sent to the ASP.NET page by using ActionScript 2.0 programming language. The application developed by using C# programming language enables programming the experimental hardware that includes a signal generator, a Raspberry Pi 2 with a camera, an oscilloscope, and a new test card. In the Raspberry Pi 2, Python programming language was used to select the desired experiment from those present on the board and to control digitally programmable circuit components such as digital potentiometers or parameters such as the DC reference voltage level. When the student successfully completes the predefined experimental procedures, an automatically generated e‐mail is sent to the instructor including the student's username, log‐in time, the oscilloscope screenshots, and ideal experimental results.
Chemoenzymatic Buta‐1,3‐diene Synthesis from Syngas Using Biological Decarboxylative Claisen Condensation and Zeolite‐Based Dehydration
Authors: Balasubramaniam Sivaraman , Badle Sneh , Badgujar Swati , Veetil Vinod P. , Rangaswamy Vidhya
Published: September 2020

A method for producing buta‐1,3‐diene (1,3‐BD) by an amalgamation of chemical and biological approaches with syngas as the carbon source is proposed. Syngas is converted to the central intermediate, acetyl‐CoA, by microorganisms through a tetrahydrofolate metabolism pathway. Acetyl‐CoA is subsequently converted to malonyl‐CoA using a carbonyl donor in the presence of a carboxylase enzyme. A decarboxylative Claisen condensation of malonyl‐CoA and acetaldehyde ensues in the presence of acyltransferases to form 3‐hydroxybutyryl‐CoA, which is subsequently reduced by aldehyde reductase to give butane‐1,3‐diol (1,3‐BDO). An ensuing dehydration step converts 1,3‐BDO to 1,3‐BD in the presence of a chemical dehydrating reagent.
Zeolite Heat Storage: Key Parameters from Experimental Results with Binder‐Free NaY
Authors: Rönsch Stefan , Auer Bernhard , Kinateder Matthias , Gleichmann Kristin
Published: September 2020

The application of heat storage systems in households or the industry is one possibility to optimize the degree of heat utilization and to reduce greenhouse gas emissions. In contrast to established heat storage systems based on water, zeolitic systems reach energy densities of 150–200 kWh m−3 and allow for seasonal storage with almost no heat loss. However, a commercial breakthrough was not yet successful. Given this background, it is the aim of the present study to identify appropriate operational parameters for a zeolite heat storage system in the laboratory and to prepare an upscaling to demonstration scale. To this end, the pressure drop of the zeolite bed, the cycle time, and the optimal process parameters during thermal loading and deloading were determined.
Recent Progress of Ruthenium‐based Nanomaterials for Electrochemical Hydrogen Evolution
Authors: Zhang Shan , Li Jing , Wang Erkang
Published: September 2020

Large‐scale hydrogen production through electrocatalytic water splitting holds great promise to alleviate the energy crisis and environmental issue. For cathodic hydrogen evolution reaction (HER), developing efficient and low‐cost electrocatalysts is highly desired to accelerate the reactive process and reduce energy consumption. In past few years, ruthenium and ruthenium‐based compounds electrocatalysts emerge as alternatives for the benchmark platinum for HER. Herein, the recent advances for the preparation of ruthenium‐based electrocatalysts towards HER is summarized, then we also discuss the prospect and challenge for the development of effective electrocatalysts based on ruthenium.
Confined Synthesis of N, P Co–Doped 3D Hierarchical Carbons as High‐Efficiency Oxygen Reduction Reaction Catalysts for Zn–Air Battery
Authors: Chen Siru , Cui Ming , Yin Zehao , Zeng Qi , Cao Zhenyu , Xiong Jiabin , Mi Liwei , Li Yanqiang
Published: September 2020

Oxygen reduction reaction (ORR) catalysts with hierarchical pore structures, high specific surface area and multiple heteroatoms doping is very attractive due to the rapid mass transport and abundant active sites. In this work, we reported a facile confined strategy to prepare N, P co‐doped hierarchical porous carbon (NPHC) and investigated their catalytic performance for ORR. The strategy greatly simplifies the synthesis procedure of 3D hierarchical carbon templated by SiO2, which can utilize small organic molecules as carbon sources and avoids the pre‐polymerization and post‐washing process. Moreover, this strategy can be readily extended to synthesis other carbons by simply changing the carbon sources and heteroatom sources, or to synthesize metal compounds/carbon composites by adding metal sources during the synthesis process for energy conversion and storage.
Synthetic Tigliane Intermediates Engage Thiols to Induce Potent Cell Line Selective Anti‐Cancer Activity
Authors: Chow Sharon , Krainz Tanja , Bettencourt Christian J. , Broit Natasa , Ferguson Blake , Zhu Mingzhao , Hull Kenneth G. , Pierens Gregory K. , Bernhardt Paul V. , Parsons Peter G. , Romo Daniel , Boyle Glen M. , Williams Craig M.
Published: September 2020

The tigliane ring system, which encompasses iconic members such as phorbol and TPA, is widely renowned due to numerous observations of displaying potent biological activity, and subsequent use as mainstream biochemical tools. Traditionally, naturally occurring phorboids are regarded as tumor promotors through PKC activation, although in recent times more highly oxidized natural derivatives have been identified as anti‐tumor agents. In the view that only limited synthetic investigations toward skeletal stereochemical modification have been undertaken, non‐natural systems could be useful for a better understanding of the tigliane pharmacophore via interrogation of cellular sensitivity. In this context the concise construction of a number of highly functionalized non‐natural D‐ring inverted phorbol esters were synthesized, via a rhodium‐catalyzed [4+3] cycloaddition, and biologically evaluated using a range of cancer cell lines. The biological results highlight the notion that subtle changes in structure have dramatic effects on potency. Furthermore, although the non‐natural derivatives did not outcompete the natural systems in the PKC‐activation sensitive MCF7 cancer cell line, they outperformed in other cancer cell lines (MM96L and CAL27). This observation strongly suggested an alternate mode of action not involving activation of PKC, but instead involves thiol addition as indicated by glutathione addition and NF‐κB reporter activity.
Transition Metal‐Promoted Reactions in Aqueous Media and Biological Settings
Authors: Destito Paolo , Vidal Cristian , López Fernando , Mascareñas José L.
Published: September 2020

During the last decade, there has been a tremendous interest for developing non‐natural biocompatible transformations in biologically relevant media. Among the different encountered strategies, the use of transition metal complexes offers unique possibilities due to their high transformative power. However, translating the potential of metal catalysts to biological settings, including living cells or small‐animal models such as mice or zebrafish, poses numerous challenges associated to their biocompatibility, and their stability and reactivity in crowded aqueous environments. Herein, we describe the most relevant advances in this direction, with a particular emphasis on the systems’ structure, their mode of action and the mechanistic bases of each transformation. Thus, the key challenges from an organometallic perspective might be more easily identified.
CO‐Induced Dinitrogen Fixation and Cleavage Mediated by Boron
Authors: Deng Guohai , Pan Sudip , Dong Xuelin , Wang Guanjun , Zhao Lili , Zhou Mingfei , Frenking Gernot
Published: September 2020

The boron atoms react with carbon monoxide and dinitrogen forming the end‐on bonded NNBCO complex in solid neon or in nitrogen matrices. The NNBCO complex rearranges to the (η2‐N2)BCO isomer with a more activated side‐on bonded dinitrogen ligand upon visible light excitation. (η2‐N2)BCO and its weakly CO‐coordinated complexes further isomerize to the NBNCO and B(NCO)2molecules with N−N bond being completely cleaved under UV light irradiation. The geometries, energies and vibrational spectra of the molecules are calculated with quantum chemical methods and the electronic structures are analyzed with charge‐ and energy‐partitioning methods.
Insights into the prognosis of lipidomic dysregulation for death risk in patients with coronary artery disease
Authors: Qin Min , Zhu Qian , Lai Weihua , Ma Qilin , Liu Chen , Chen Xiaoping , Zhang Yuelin , Wang Zixian , Chen Hui , Yan Hong , Lei Heping , Zhang Shuyao , Dong Xuekui , Wang Hong , Huang Min , Lian Qizhou , Zhong Shilong
Published: September 2020

Background

Dyslipidaemia contributes to the progression of coronary artery disease (CAD) toward adverse outcomes. Plasma lipidomic measure may improve the prognostic performances of clinical endpoints of CAD. Our research is designed to identify the correlations between plasma lipid species and the risks of death, major adverse cardiovascular event (MACE) and left ventricular (LV) remodeling in patients with CAD.

Methods

A total of 1569 Chinese patients with CAD, 1011 single‐centre patients as internal training cohort, and 558 multicentre patients as external validation cohort, were enrolled. The concentration of plasma lipids in both cohorts was determined through widely targeted lipidomic profiling. Least absolute shrinkage and selection operator Cox and multivariate Cox regressions were used to develop prognostic models for death and MACE, respectively.

Results

Ten (Cer(d18:1/20:1), Cer(d18:1/24:1), PE(30:2), PE(32:0), PE(32:2), PC(O‐38:2), PC(O‐36:4), PC(16:1/22:2), LPC(18:2/0:0) and LPE(0:0/24:6)) and two (Cer(d18:1/20:1) and LPC(20:0/0:0)) lipid species were independently related to death and MACE, respectively. Cer(d18:1/20:1) and Cer(d18:1/24:1) were correlated with LV remodeling (P < .05). The lipidic panel incorporating 10 lipid species and two traditional biomarkers for predicting 5‐year death risk represented a remarkable higher discrimination than traditional model with increased area under the curve from 76.56 to 83.65%, continuous NRI of 0.634 and IDI of 0.131. Furthermore, the panel was successfully used in differentiating multicentre patients with low, middle, or high risks (P < .0001). Further analysis indicated that the number of double bonds of phosphatidyl choline and the content of carbon atoms of phosphatidyl ethanolamines were negatively associated with death risk.

Conclusions

Improvement in the prediction of death confirms the effectiveness of plasma lipids as predictors to risk classification in patients with CAD. The association between the structural characteristics of long‐chain polyunsaturated fatty acids and death risk highlights the need for mechanistic research that characterizes the role of individual lipid species in disease pathogenesis.
Redesign your in‐person course for online: Creating connections and promoting engagement for better learning
Authors: Theodosiou Nicole A. , Corbin Jeffrey D.
Published: September 2020

This spring, instructors moved their courses online in an emergency fashion as campuses were closed due to the pandemic. As colleges prepare for the next academic year, there is a need to provide flexible instruction that is more intentional for quality online learning. We taught two undergraduate courses online for the first time this spring and surveyed our students’ reactions to the course experiences. From our experiences and student feedback, we identified design elements and activities that were beneficial in promoting student engagement, sense of connectivity, and learning. We describe four qualities for a successful transition to online learning: (a) big questions and core concepts; (b) peer groups including reflective writing; (c) outreach to broader scientific community; and (d) instructor's social presence in the class. Our experience gives us confidence that courses can be redesigned for online without compromising rigor or essential learning goals.
Signaler–receiver–eavesdropper: Risks and rewards of variation in the dominant frequency of male cricket calls
Authors: Dobbs Olivia L. , Talavera Janelle B. , Rossi Sarina M. , Menjivar Stephanie , Gray David A.
Published: September 2020

Signals are important for communication and mating, and while they can benefit an individual, they can also be costly and dangerous. Male field crickets call in order to attract female crickets, but gravid females of a parasitoid fly species, Ormia ochracea, are also attracted to the call and use it to pinpoint male cricket hosts. Conspicuousness of the call can vary with frequency, amplitude, and temporal features. Previous work with this system has only considered temporal variation in cricket calls, both large scale, that is, amount of calling and at what time of evening, and small scale, that is, aspects of chirp rate, pulse rate, and numbers of pulses per chirp. Because auditory perception in both crickets and flies relies on the matching of the peak frequency of the call with the peripheral sensory system, peak frequency may be subject to selection both from female crickets and from female flies. Here, we used field playbacks of four different versions of the same male Gryllus lineaticeps calling song that only differed in peak frequency (3.3, 4.3, 5.3, and 6.3 kHz) to test the relative attractiveness of the calls to female crickets and female flies. Our results clearly show that lower frequency calls enhance male safety from fly parasitism, but that the enhanced safety would come at a cost of reduced attraction of female crickets as potential mates. The results imply that eavesdropper pressure can disrupt the matched coevolution of signalers and receivers such that the common concept of matched male–female signaler–receiver coevolution may actually be better described as male–female–predator signaler–receiver–eavesdropper coevolution.
Seismic performance assessment of a multispan continuous isolated highway bridge with superelastic shape memory alloy reinforced piers and restraining devices
Authors: Li Shuai , Wang Jing‐quan , Alam M. Shahria
Published: September 2020

The objective of this study is to analytically determine the effectiveness of a novel bridge system with superelastic (SE) shape memory alloy (SMA) reinforced concrete piers. The bridge is also equipped with SE SMA cable restrainers to prevent the bridge spans from a large displacement that can potentially cause span unseating. In the concrete bridge piers, the conventional steel reinforcements in the plastic hinge regions are replaced with SE SMA rebar to avoid large plastic deformation and improve its self‐centering capacity. A typical three‐span continuous highway bridge is modeled with SMA‐reinforced piers and SMA restrainers. Numerical simulations of the bridge are conducted under destructive near‐fault ground motions. The seismic responses and fragility curves of the novel bridge (Bridge IV) are assessed and compared with the reference bridge (Bridge I), the bridge with only SMA‐reinforced piers (Bridge II), and the bridge with only SMA restrainers (Bridge III). The results revealed that the SMA‐reinforced pier can successfully reduce the residual deformation and damage probability of the bridge; however, the bridge with only SMA‐reinforced piers is less efficient in preventing a large displacement. The use of SMA restrainers can efficiently limit the displacement of the bridge spans but increase the damage probability of the bridge piers. The proposed novel bridge having SMA‐reinforced piers equipped with SMA restrainers (Bridge IV) is more efficient than the bridge with only SMA‐reinforced piers (Bridge II)) or the bridge with only SMA restrainers (Bridge III).
TWO‐SIGMA: A novel two‐component single cell model‐based association method for single‐cell RNA‐seq data
Authors: Van Buren Eric , Hu Ming , Weng Chen , Jin Fulai , Li Yan , Wu Di , Li Yun
Published: September 2020

In this paper, we develop TWO‐SIGMA, a TWO‐component SInGle cell Model‐based Association method for differential expression (DE) analyses in single‐cell RNA‐seq (scRNA‐seq) data. The first component models the probability of “drop‐out” with a mixed‐effects logistic regression model and the second component models the (conditional) mean expression with a mixed‐effects negative binomial regression model. TWO‐SIGMA is extremely flexible in that it: (i) does not require a log‐transformation of the outcome, (ii) allows for overdispersed and zero‐inflated counts, (iii) accommodates a correlation structure between cells from the same individual via random effect terms, (iv) can analyze unbalanced designs (in which the number of cells does not need to be identical for all samples), (v) can control for additional sample‐level and cell‐level covariates including batch effects, (vi) provides interpretable effect size estimates, and (vii) enables general tests of DE beyond two‐group comparisons. To our knowledge, TWO‐SIGMA is the only method for analyzing scRNA‐seq data that can simultaneously accomplish each of these features. Simulations studies show that TWO‐SIGMA outperforms alternative regression‐based approaches in both type‐I error control and power enhancement when the data contains even moderate within‐sample correlation. A real data analysis using pancreas islet single‐cells exhibits the flexibility of TWO‐SIGMA and demonstrates that incorrectly failing to include random effect terms can have dramatic impacts on scientific conclusions. TWO‐SIGMA is implemented in the R package twosigma available at https://github.com/edvanburen/twosigma.
Epidemiologic factors in patients with advanced head and neck cancer treated with radiation therapy
Authors: Brennan Michael T. , Treister Nathaniel S. , Sollecito Thomas P. , Schmidt Brian L. , Patton Lauren L. , Yang Yi , Lin Alexander , Elting Linda S. , Hodges James S. , Lalla Rajesh V.
Published: September 2020

Background

Approximately 50% of patients with head and neck cancer (HNC) initially were seen with advanced disease. We aimed to evaluate the association of epidemiologic factors with advanced HNC at diagnosis.

Methods

The OraRad multicenter prospective cohort study enrolled HNC patients receiving curative‐intent radiation therapy. Factors assessed for association with advanced HNC presentation at diagnosis included demographics, social and medical history, cancer characteristics, human papilloma virus (HPV) status, and dental disease measures.

Results

We enrolled 572 participants; 77% male and mean (SD) age of 61.7 (11.2) years. Oropharyngeal squamous cell carcinomas (88% HPV‐related) were seen with smaller tumors, but more frequent nodal involvement. Private medical insurance and no Medicaid were associated with smaller tumors. A higher dental disease burden was associated with larger tumors.

Conclusions

Insurance status, cancer type/location, and dental disease are associated with advanced HNC and may represent potentially modifiable factors or factors to be considered in the screening process of new lesions.
Rapid recurrence in head and neck cancer: Underappreciated problem with poor outcome
Authors: Lee Douglas Y. , Abraham Jesty , Ross Eric , Ridge John A. , Lango Miriam N. , Liu Jeffrey C. , Bauman Jessica R. , Avkshtol Vladimir , Galloway Thomas J.
Published: September 2020

Background

Rapid recurrence, defined as gross tumor recurrence after primary operation but prior to initiating postoperative radiation therapy (PORT), is underappreciated in head and neck cancer (HNC).

Methods

CT simulation images in patients with HNC managed surgically with adjuvant therapy at a single center between 2010 and 2017 were retrospectively reviewed.

Results

A total of 194 patients with HNC were included. Rapid recurrence occurred in 39 patients (20%) with a median time from operation to CT simulation of 37 days. On multivariable analysis (MVA), extranodal extension (ENE) was the only predictor of rapid recurrence (P = .03). While rapid recurrence, ENE, and perineural invasion were all associated with poor overall survival (OS) on MVA, rapid recurrence was the strongest predictor (hazard ratio [HR] 5.47).

Conclusion

Rapid recurrence occurs at an underappreciated rate and is associated with poor survival outcomes. Patients with ENE are at highest risk and may benefit from diagnostic imaging evaluations immediately prior to PORT.
Cervical cancer in low‐income countries: A Bangladeshi perspective
Authors: Hoque Mohammad Razuanul , Haque Effi , Karim M. Rezaul
Published: September 2020

Cervical cancer is the fourth most common cancer among women worldwide, with approximately 70% of cases involving infection with human papillomavirus (HPV) genotypes 16 and 18. According to International Agency for Research on Cancer, more than 50 million Bangladeshi women are at risk of developing cervical cancer, and 17 686 new cases and 10 362 deaths occur annually. If diagnosed at the precursor stage, however, cervical cancer is a condition that can be successfully treated. As a result, screening programs are necessary to identify the disease before it progresses to invasive cancer. In the present review, we discuss the overall situation of cervical cancer in Bangladesh, summarizing the sociodemographic status of affected women, associated risk factors, screening approaches, and treatment options. We emphasize the potential of visual inspection with acetic acid (VIA) as a cost‐effective screening approach for detecting cervical lesions among poor women in the community. In a resource‐limited country such as Bangladesh, VIA may represent an ideal model to build an effective awareness campaign through urban and rural hospitals, community‐based clinics, and other health facilities available in industry.
A comparison of intervention for problematic speech using reinforcement with and without preferred topics
Authors: Stocco Corey S. , Saavedra Ingrid , Fakharzadeh Sadaf , Patel Meg R. , Thompson Rachel H.
Published: September 2020

Previous research has shown that responding to the appropriate and problematic speech of individuals diagnosed with developmental disabilities with interested and uninterested listener responses, respectively, can promote more appropriate conversational engagement. However, Fisher et al. (2013) also responded to appropriate speech with access to preferred conversational topics. This study examined the influence of listener interest on the problematic speech of 8 participants and tested the additive effects of (Study 1) and participant preference for (Study 2) delivering preferred topics as reinforcement for appropriate speech. Interventions were equally effective with or without arranging access to preferred topics, but a majority of participants demonstrated a preference for intervention with contingent access to preferred topics. Caregivers and speech‐language pathologists rated the intervention procedures as acceptable and changes in participants' speech satisfactory.
Teriparatide Did Not Increase Adult Osteosarcoma Incidence in a 15-Year US Postmarketing Surveillance Study
Authors: Gilsenan Alicia , Midkiff Kirk , Harris David , Kellier-Steele Nicole , McSorley David , Andrews Elizabeth B
Published: September 2020

The Osteosarcoma Surveillance Study was initiated in the United States in 2003 to monitor for a potential association between the osteoporosis treatment teriparatide and osteosarcoma. Osteosarcoma occurs at a background incidence rate of approximately 2.5 cases per million per year in US adults aged 40 years or older. For this study, incident cases of osteosarcoma diagnosed between January 1, 2003, and December 31, 2016, were identified through participating cancer registries in the United States. Information on prior exposure to medications and possible risk factors was obtained by self-report (or proxy report) in telephone interviews. Exposure information was verified through medical record abstraction for a sample of patients. A standardized incidence ratio was estimated to compare the observed and expected numbers of osteosarcoma patients with a prior history of teriparatide treatment. Interviews were completed for 24% (1173) of patients diagnosed with osteosarcoma between 2003 and 2016; three reports of teriparatide use before diagnosis were identified. Based on the background incidence rate, the expected number of osteosarcoma cases among patients treated with teriparatide was 4.17. Given the three observed cases, the standardized incidence ratio was 0.72 (90% confidence interval [CI], 0.20 to 1.86). Demographic characteristics were similar for interviewed and noninterviewed patients. Agreement was >90% between self-reported and chart-recorded exposure to osteoporosis medications. Mean age of interviewed patients was 61 years; 53% of patients were male, 84% were white, and 5% were Hispanic. The prevalence of suspected risk factors for development of osteosarcoma among the osteosarcoma cohort was 19% for history of radiation and 4% for history of Paget's disease of bone. These findings showed that the incidence of osteosarcoma associated with teriparatide use during the 15-year surveillance period was no different than would be expected based on the background incidence rate of osteosarcoma. © 2020 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).
Neuroprotective role of chrysin‐loaded poly(lactic‐co‐glycolic acid) nanoparticle against kindling‐induced epilepsy through Nrf2/ARE/HO‐1 pathway
Authors: Zhang Ying , Zhao Jing , Afzal Obaid , Kazmi Imran , Al‐Abbasi Fahad A. , Altamimi Abdulmalik S. A. , Yang Zhen
Published: September 2020

Chrysin is the major bioactive compound of blue passionflower, an important medicinal plant used in traditional herbal formulations since ancient times. In the present study, we report that chrysin nanoparticles (chrysin NPs) protect Wistar rats against kindling‐induced epilepsy. Nanoparticles of sizes less than 150 nm with a spherical shape were prepared using poly(d,l‐lactic‐co‐glycolic acid) and polyvinyl alcohol, respectively, as polymer and stabilizer. Rats were injected with subconvulsive doses of pentylenetetrazole (PTZ) (35 mg/kg, intraperitoneal) every second day, with 22 injections in total, and on the same days, they received protective doses of the chrysin NPs (5 and 10 µg/mL, PO), respectively, 45 min before each PTZ injection. After the last PTZ injection, an average of thirteen seizure scores was recorded. Animals were killed by decapitation 24 h after a seizure. The cortex and hippocampus were removed and stored in liquid nitrogen for determining oxidative stress terminal deoxynucleotidyl transferase dUTP nick‐end labeling assay, histopathology, and reverse transcription‐polymerase chain reaction for messenger RNA expression. The result showed chrysin NPs treatment has counteracted oxidative stress, reduced neuronal apoptosis, and upregulated nuclear factor erythroid 2‐related factor 2 (Nrf2), heme oxygenase‐1 (HO‐1), and NAD(P)H quinone oxidoreductase 1. In conclusion, our findings demonstrate that the neuroprotective effect of chrysin NPs against kindling‐induced epilepsy might be escorted by the alleviation of oxidative stress through the Nrf2/antioxidant response element/HO‐1 pathway signal pathway.