bluuebunny/crossref_metadata_2025_split huggingface dataset:
Catalytic SNAr Hydroxylation and Alkoxylation of Aryl Fluorides
Authors: Kang Qi‐Kai , Lin Yunzhi , Li Yuntong , Xu Lun , Li Ke , Shi Hang 
Published: July 2021

AbstractNucleophilic aromatic substitution (SNAr) is a powerful strategy for incorporating a heteroatom into an aromatic ring by displacement of a leaving group with a nucleophile, but this method is limited to electron‐deficient arenes. We have now established a reliable method for accessing phenols and phenyl alkyl ethers via catalytic SNAr reactions. The method is applicable to a broad array of electron‐rich and neutral aryl fluorides, which are inert under classical SNAr conditions. Although the mechanism of SNAr reactions involving metal arene complexes is hypothesized to involve a stepwise pathway (addition followed by elimination), experimental data that support this hypothesis is still under exploration. Mechanistic studies and DFT calculations suggest either a stepwise or stepwise‐like energy profile. Notably, we isolated a rhodium η5‐cyclohexadienyl complex intermediate with an sp3‐hybridized carbon bearing both a nucleophile and a leaving group.
Hemicyanine‐Based Near‐Infrared Activatable Probes for Imaging and Diagnosis of Diseases
Authors: Zeng Ziling , Liew Si Si , Wei Xin , Pu Kanyi 
Published: July 2021

AbstractMolecular activatable probes with near‐infrared (NIR) fluorescence play a critical role in in vivo imaging of biomarkers for drug screening and disease diagnosis. With structural diversity and high fluorescence quantum yields, hemicyanine dyes have emerged as a versatile scaffold for the construction of activatable optical probes. This Review presents a survey of hemicyanine‐based NIR activatable probes (HNAPs) for in vivo imaging and early diagnosis of diseases. The molecular design principles of HNAPs towards activatable optical signaling against various biomarkers are discussed with a focus on their broad applications in the detection of diseases including inflammation, acute organ failure, skin diseases, intestinal diseases, and cancer. This progress not only proves the unique value of HNAPs in preclinical research but also highlights their high translational potential in clinical diagnosis.
A Neutral Beryllium(I) Radical
Authors: Czernetzki Corinna , Arrowsmith Merle , Fantuzzi Felipe , Gärtner Annalena , Tröster Tobias , Krummenacher Ivo , Schorr Fabian , Braunschweig Holger 
Published: July 2021

AbstractThe reduction of a cyclic alkyl(amino)carbene (CAAC)‐stabilized organoberyllium chloride yields the first neutral beryllium radical, which was characterized by EPR, IR, and UV/Vis spectroscopy, X‐ray crystallography, and DFT calculations.
Antibacterial properties of polyaniline derivatives
Authors: Andriianova Anastasiia N. , Latypova Lyaysan R. , Vasilova Liliya Ya. , Kiseleva Sofia V. , Zorin Vladimir V. , Abdrakhmanov Ildus B. , Mustafin Akhat G. 
Published: July 2021

AbstractThis work presents a detailed study on the effect of various functional groups both at the ortho position of the aromatic ring and in the amino group of PANI on the antibacterial properties of polymers against gram‐positive (Bacillus subtilis) and gram‐negative (Pseudomonas aureofaciens) microorganisms. It was found that incorporation of methyl, methoxy, or pentyl groups into the ortho‐position of PANI did not increase the antibacterial activity but in most cases causes a significant decrease in the antibacterial properties of functionally substituted polyanilines. At the same time, PANI derivatives modified by incorporation of pentyl groups into the amino group were found to be more efficient antibacterial compounds against both gram‐positive and gram‐negative microorganisms than the original polymer. It was also found that N‐substituted PANI derivatives manifest not only bactericidal but also bacteriostatic properties toward the test microorganisms. Varying the nature and position of the substituent allowed us to conclude that the synthesis of various N‐substituted PANI derivatives with a high degree of doping is the most promising approach to PANI modification for application in bacterial growth inhibition.
FDEM and ERT measurements for archaeological prospections at Nuraghe S'Urachi (West‐Central Sardinia)
Authors: Deiana Rita , Deidda Gian Piero , Cusí Enrique Díes , van Dommelen Peter , Stiglitz Alfonso 
Published: July 2021

AbstractNuraghe S'Urachi is a monumental architectural complex in West Central Sardinia that was probably first built in the Bronze Age and remained occupied continuously into the early Roman Imperial period. It has been the object of systematic and large‐scale archaeological investigations in three different phases since 1948 when the first excavations revealed a complex building within a massive defensive wall and multiple towers. Intermittent fieldwork between the 1980s and 2005 subsequently showed that the central nuraghe might comprise up to five principal towers. In 2013, a new collaborative research project, sponsored by Brown University and the Municipality of San Vero Milis, brought together a multidisciplinary research project to investigate this important archaeological site. In this framework, multi‐frequency and multi‐coil electromagnetic measurements (FDEM) and Electrical resistivity tomography (ERT) were carried out in 2018, 2019, and 2020, over and close to the nuraghe towers, to gain a better understanding of the inner part of the main structure and to investigate the surrounding area that was intensively settled in Phoenician and Punic times. The preliminary results of the geophysical measurements provide new and interesting evidence that supports new hypotheses and suggests possible future archaeological and geophysical strategies to investigate the unexcavated part of the archaeological site of S'Urachi.
Recent Progress in High‐Performance Lithium Sulfur Batteries: The Emerging Strategies for Advanced Separators/Electrolytes Based on Nanomaterials and Corresponding Interfaces
Authors: Wang Xiaoxiao , Deng Nanping , Wei Liying , Yang Qi , Xiang Hengying , Wang Meng , Cheng Bowen , Kang Weimin 
Published: July 2021

AbstractLithium‐sulfur (Li−S) batteries, possessing excellent theoretical capacities, low cost and nontoxicity, are one of the most promising energy storage battery systems. However, poor conductivity of elemental S and the “shuttle effect” of lithium polysulfides hinder the commercialization of Li−S batteries. These problems are closely related to the interface problems between the cathodes, separators/electrolytes and anodes. The review focuses on interface issues for advanced separators/electrolytes based on nanomaterials in Li−S batteries. In the liquid electrolyte systems, electrolytes/separators and electrodes system can be decorated by nano materials coating for separators and electrospinning nanofiber separators. And, interface of anodes and electrolytes/separators can be modified by nano surface coating, nano composite metal lithium and lithium nano alloy, while the interface between cathodes and electrolytes/separators is designed by nano metal sulfide, nanocarbon‐based and other nano materials. In all solid‐state electrolyte systems, the focus is to increase the ionic conductivity of the solid electrolytes and reduce the resistance in the cathode/polymer electrolyte and Li/electrolyte interfaces through using nanomaterials. The basic mechanism of these interface problems and the corresponding electrochemical performance are discussed. Based on the most critical factors of the interfaces, we provide some insights on nanomaterials in high‐performance liquid or state Li−S batteries in the future.
Novel switching signal selection for robust passive sampled‐data control of uncertain continuous switched time‐delay systems
Authors: Lien Chang‐Hua , Hou Yi‐You , Yu Ker‐Wei , Chang Hao‐Chin 
Published: July 2021

AbstractIn this paper, the robust passive sampled‐data controls of uncertain continuous switched time‐delay systems with linear fractional perturbations and aperiodic sampling are considered. By the proposed delay‐dependent linear matrix inequality (LMI)‐based criteria, the switching domains can be selected to design the switching signal and sampled‐data control. If switching signal is known, the feedback control can be designed by using the sampled state at each sampling instant. Some simulations are provided to verify the efficiency of the proposed results. Finally, some numerical examples are illustrated to show the main contribution of the proposed results.
Rapid and cost‐effective process based on insect larvae for scale‐up production of SARS‐COV‐2 spike protein for serological COVID‐19 testing
Authors: Smith Ignacio , Mc Callum Gregorio Juan , Sabljic Adriana Victoria , Marfia Juan Ignacio , Bombicino Silvina Sonia , Trabucchi Aldana , Iacono Ruben Francisco , Birenbaum Joaquín Manuel , Vazquez Susana Claudia , Minoia Juan Mauricio , Cascone Osvaldo , López María Gabriela , Taboga Oscar , Targovnik Alexandra Marisa , Wolman Federico Javier , Fingermann Matías , Alonso Leonardo Gabriel , Valdez Silvina Noemí , Miranda María Victoria 
Published: July 2021

AbstractSerology testing for COVID‐19 is important in evaluating active immune response against SARS‐CoV‐2, studying the antibody kinetics, and monitoring reinfections with genetic variants and new virus strains, in particular, the duration of antibodies in virus‐exposed individuals and vaccine‐mediated immunity. In this study, recombinant S protein of SARS‐CoV‐2 was expressed in Rachiplusia nu, an important agronomic plague. One gram of insect larvae produces an amount of S protein sufficient for 150 determinations in the ELISA method herein developed. We established a rapid production process for SARS‐CoV‐2 S protein that showed immunoreactivity for anti‐SARS‐CoV‐2 antibodies and was used as a single antigen for developing the ELISA method with high sensitivity (96.2%) and specificity (98.8%). Our findings provide an efficient and cost‐effective platform for large‐scale S protein production, and the scale‐up is linear, thus avoiding the use of complex equipment like bioreactors.
Biodegradable and biocompatible graphene‐based scaffolds for functional neural tissue engineering: A strategy approach using dental pulp stem cells and biomaterials
Authors: Mansouri Negar , Al‐Sarawi Said , Losic Dusan , Mazumdar Jagan , Clark Jillian , Gronthos Stan , O'Hare Doig Ryan 
Published: July 2021

AbstractNeural tissue engineering aims to restore the function of nervous system tissues using biocompatible cell‐seeded scaffolds. Graphene‐based scaffolds combined with stem cells deserve special attention to enhance tissue regeneration in a controlled manner. However, it is believed that minor changes in scaffold biomaterial composition, internal porous structure, and physicochemical properties can impact cellular growth and adhesion. The current work aims to investigate in vitro biological effects of three‐dimensional (3D) graphene oxide (GO)/sodium alginate (GOSA) and reduced GOSA (RGOSA) scaffolds on dental pulp stem cells (DPSCs) in terms of cell viability and cytotoxicity. Herein, the effects of the 3D scaffolds, coating conditions, and serum supplementation on DPSCs functions are explored extensively. Biodegradation analysis revealed that the addition of GO enhanced the degradation rate of composite scaffolds. Compared to the 2D surface, the cell viability of 3D scaffolds was higher (p < 0.0001), highlighting the optimal initial cell adhesion to the scaffold surface and cell migration through pores. Moreover, the cytotoxicity study indicated that the incorporation of graphene supported higher DPSCs viability. It is also shown that when the mean pore size of the scaffold increases, DPSCs activity decreases. In terms of coating conditions, poly‐
l‐lysine was the most robust coating reagent that improved cell‐scaffold adherence and DPSCs metabolism activity. The cytotoxicity of GO‐based scaffolds showed that DPSCs can be seeded in serum‐free media without cytotoxic effects. This is critical for human translation as cellular transplants are typically serum‐free. These findings suggest that proposed 3D GO‐based scaffolds have favorable effects on the biological responses of DPSCs.
Cellular and molecular mechanisms of perineural invasion of pancreatic ductal adenocarcinoma
Authors: Li Jingbo , Kang Rui , Tang Daolin 
Published: July 2021

AbstractPancreatic ductal adenocarcinoma (PDAC) is an aggressive malignant disease with a unique tumor microenvironment surrounded by an interlaced network of cancer and noncancerous cells. Recent works have revealed that the dynamic interaction between cancer cells and neuronal cells leads to perineural invasion (PNI), a clinical pathological feature of PDAC. The formation and function of PNI are dually regulated by molecular (e.g., involving neurotrophins, cytokines, chemokines, and neurotransmitters), metabolic (e.g., serine metabolism), and cellular mechanisms (e.g., involving Schwann cells, stromal cells, T cells, and macrophages). Such integrated mechanisms of PNI not only support tumor development, growth, invasion, and metastasis but also mediate the formation of pain, all of which are closely related to poor disease prognosis in PDAC. This review details the modulation, signaling pathways, detection, and clinical relevance of PNI and highlights the opportunities for further exploration that may benefit PDAC patients.
Rational Design of Programmable Monodisperse Semi‐Synthetic Protein Nanomaterials Containing Engineered Disulfide Functionality**
Authors: Bhandari Pavankumar Janardhan , Sandanaraj Britto S. 
Published: July 2021

AbstractThe reversible nature of disulfide functionality has been exploited to design intelligent materials such as nanocapsules, micelles, vesicles, inorganic nanoparticles, peptide and nucleic acid nanodevices. Herein, we report a new chemical methodology for the construction redox‐sensitive protein assemblies using monodisperse facially amphiphilic protein‐dendron bioconjugates. The disulfide functionality is strategically placed between the dendron and protein domains. The custom designed bioconjugates self‐assembled into nanoscopic objects of a defined size dictated by the nature of dendron domain. The stimuli‐responsive behavior of the protein assemblies is demonstrated using a suitable redox trigger.
An Autophagy‐Disrupting Small Molecule Promotes Cancer Cell Death via Caspase Activation
Authors: Park Sang‐Hyun , Shin Insu , Kim Gun‐Hee , Ko Sung‐Kyun , Shin Injae 
Published: July 2021

AbstractA novel autophagy inhibitor, autophazole (Atz), which promoted cancer cell death via caspase activation, is described. This compound was identified from cell‐based high‐content screening of an imidazole library. The results showed that Atz was internalized into lysosomes of cells where it induced lysosomal membrane permeabilization (LMP). This process generated nonfunctional autolysosomes, thereby inhibiting autophagy. In addition, Atz was found to promote LMP‐mediated apoptosis. Specifically, LMP induced by Atz caused release of cathepsins from lysosomes into the cytosol. Cathepsins in the cytosol cleaved Bid to generate tBid, which subsequently activated Bax to induce mitochondrial outer membrane permeabilization (MOMP). This event led to cancer cell death via caspase activation. Overall, the findings suggest that Atz will serve as a new chemical probe in efforts aimed at gaining a better understanding of the autophagic process.
Less‐invasive diagnosis of disseminated epithelioid glioblastoma harboring BRAF V600E mutation by cerebrospinal fluid analysis—A case report
Authors: Natsumeda Manabu , Kanemaru Yu , Kawaguchi Yukie , Umezu Hajime , Kakita Akiyoshi , Fujii Yukihiko 
Published: July 2021

AbstractSpinal dissemination in epithelioid glioblastoma can be diagnosed by cerebrospinal fluid cytology and liquid biopsy to detect BRAF V600E mutation.
Improved Operation of Continuous Ozone Hydrate Production
Authors: Hatsugai Tomomi , Kiyokawa Hitoshi , Takeya Satoshi , Ohmura Ryo 
Published: July 2021

AbstractIn a previous study, we have experimentally demonstrated the continuous formation of O3+O2+CO2 hydrate. Here, improved results for the O3+O2+CO2 hydrate formation are reported. By forming O3+O2+CO2 hydrate at a low temperature and higher O3 gas concentration in the gas phase, the O3 concentration in the hydrates was increased to be 0.41 mass %, which was 1.6 times higher than our past record. One‐quarter reduction of the induction time for O3+O2+CO2 hydrate formation was also achieved by raising the initial volume ratio of CO2 in the feed gas in the range of 2–2.9 times that of our previous study. Also, the overall heat transfer coefficient during O3+O2+CO2 hydrate continuous formation was experimentally determined.
Yolk–shell nanoarchitecture for stabilizing a Ce2S3 anode
Authors: Hui Kanglong , Fu Jipeng , Liu Jie , Chen Yongjin , Gao Xiang , Gao Tian , Wei Qi , Li Chengyu , Zhang Hongjie , Tang Mingxue 
Published: July 2021

AbstractRare‐earth sulfides are of research interest for lithium‐ion batteries (LIBs) due to their abundant lithium intercalation sites and low redox voltage. However, their electrochemical performances are not satisfactory because of poor conductivity and volume change upon electrochemical cycling. Herein, nanoarchitectures of γ‐Ce2S3 encapsulated in a hollow mesoporous carbon nanosphere (Ce2S3@HMCS) are fabricated using the self‐template strategy combined with the in‐sphere sulfuration method and tested as an LIB anode. The void space between the Ce2S3 core and the outer layer of the carbon nanosphere has been properly designed and modulated to achieve excellent electrochemical performance in terms of electronic conductivity, reversibility, and rate capability. The reversible capacity of Ce2S3@HMCS is 2.6 times that of the pure Ce2S3 anode, which can gradually increase and maintain a capacity of 282 mAh·g−1 at a current density of 1 A·g–1, and a high Coulombic efficiency (~100%) can be achieved even after 1000 cycles. This good performance is attributed to the unique yolk–shell nanostructure with a highly crystallized and stable Ce3S2 core and volume expansion buffer space upon lithiation/delithiation. Ex situ X‐ray diffraction and nuclear magnetic resonance results indicate that the lithiation of Ce2S3@HMCS is an intercalation process. This study represents an important advancement in precise structural design with in‐sphere sulfuration and sheds light on a potential direction for high‐performance lithium storage.
DNA‐Triggered Enhancement of Singlet Oxygen Production by Pyridinium Alkynylanthracenes
Authors: Fudickar Werner , Bauch Marcel , Ihmels Heiko , Linker Torsten 
Published: July 2021

AbstractThere is an ongoing interest in 1O2 sensitizers, whose activity is selectively controlled by their interaction with DNA. To this end, we synthesized three isomeric pyridinium alkynylanthracenes 2 o–p and a water‐soluble trapping reagent for 1O2. In water and in the absence of DNA, these dyes show a poor efficiency to sensitize the photooxygenation of the trapping reagent as they decompose due to electron transfer processes. In contrast, in the presence of DNA 1O2 is generated from the excited DNA‐bound ligand. The interactions of 2 o–p with DNA were investigated by thermal DNA melting studies, UV/vis and fluorescence spectroscopy, and linear and circular dichroism spectroscopy. Our studies revealed an intercalative binding with an orientation of the long pyridyl‐alkynyl axis parallel to the main axis of the DNA base pairs. In the presence of poly(dA : dT), all three isomers show an enhanced formation of singlet oxygen, as indicated by the reaction of the latter with the trapping reagent. With green light irradiation of isomer 2 o in poly(dA : dT), the conversion rate of the trapping reagent is enhanced by a factor >10. The formation of 1O2 was confirmed by control experiments under anaerobic conditions, in deuterated solvents, or by addition of 1O2 quenchers. When bound to poly(dG : dC), the opposite effect was observed only for isomers 2 o and 2 m, namely the trapping reagent reacted significantly slower. Overall, we showed that pyridinium alkynylanthracenes are very useful intercalators, that exhibit an enhanced photochemical 1O2 generation in the DNA‐bound state.
Construction of a Single‐Atom Nanozyme for Enhanced Chemodynamic Therapy and Chemotherapy
Authors: Liu Yong , Yao Mei , Han Wenxiu , Zhang Huairong , Zhang Shusheng 
Published: July 2021

AbstractTo fulfill the demand of precision and personalized medicine, single‐atom catalysts (SACs) have emerged as a frontier in biomedical fields due to enzyme‐mimic catalysis. Herein, we present a biocompatible and versatile nanoagent consisting of single‐atom iron‐containing nanoparticles (SAF NPs), DOX and A549 cell membrane (CM). The designed porous iron‐based SACs originally served as a drug‐carrying nanoplatform to release DOX selectively in a tumor microenvironment (TME) for chemotherapy (CT) due to their high loading capacity (155 %) for DOX; this signifies that SACs are promising candidates for universal cargo delivery. Besides, the designed single‐atom nanoagent can perform like peroxidase, which effectively triggers an in situ tumor‐specific Fenton reaction to generate abundant toxic hydroxyl radicals (⋅OH) selectively in the acidic TME for chemodynamic therapy (CDT). With the combination of CDT and CT, the constructed SAF NPs@DOX@CM nanoagent demonstrates better in vivo therapeutic performance than single‐pathway therapy. In the meantime, after modification with CM, SAF NPs@DOX@CM can achieve homologous binding to target tumor tissues and avoid early clearance. This study presents a type of multifunctional SACs for enhanced cancer treatment via the capacity of a drug carrier combined with the enzymatic therapies of single‐atom catalytic sites.
In Situ Synchrotron X‐ray Diffraction Studies of the Mechanochemical Synthesis of ZnS from its Elements
Authors: Petersen Hilke , Reichle Steffen , Leiting Sebastian , Losch Pit , Kersten Wolfgang , Rathmann Tobias , Tseng Jochi , Etter Martin , Schmidt Wolfgang , Weidenthaler Claudia 
Published: July 2021

AbstractInvited for the cover of this issue is Claudia Weidenthaler and co‐workers at the Max‐Planck‐Institut für Kohlenforschung, Shenzhen University and Deutsches Elektronen Synchrotron. The image depicts the X‐ray diffraction results showing the formation of ZnS and the subsequent phase transition from the hexagonal to the cubic modification. Read the full text of the article at 10.1002/chem.202101260.