bluuebunny/crossref_metadata_2025 huggingface dataset:
Smart and Functionalized Development of Nucleic Acid‐Based Hydrogels: Assembly Strategies, Recent Advances, and Challenges
Authors: Zhang Yangzi , Zhu Longjiao , Tian Jingjing , Zhu Liye , Ma Xuan , He Xiaoyun , Huang Kunlun , Ren Fazheng , Xu Wentao
Published: May 2021

Nucleic acid‐based hydrogels that integrate intrinsic biological properties of nucleic acids and mechanical behavior of their advanced assemblies are appealing bioanalysis and biomedical studies for the development of new‐generation smart biomaterials. It is inseparable from development and incorporation of novel structural and functional units. This review highlights different functional units of nucleic acids, polymers, and novel nanomaterials in the order of structures, properties, and functions, and their assembly strategies for the fabrication of nucleic acid‐based hydrogels. Also, recent advances in the design of multifunctional and stimuli‐responsive nucleic acid‐based hydrogels in bioanalysis and biomedical science are discussed, focusing on the applications of customized hydrogels for emerging directions, including 3D cell cultivation and 3D bioprinting. Finally, the key challenge and future perspectives are outlined.
Optical Outcoupling Efficiency in Polymer Light‐Emitting Diodes
Authors: Li Yungui , Van der Zee Bas , Wetzelaer Gert‐Jan A. H. , Blom Paul W. M.
Published: May 2021

The electrical properties of polymer‐based light‐emitting diodes (PLEDs) have been extensively studied, resulting in quantitative device models. However, for a complete description of the optoelectronic properties of a PLED, the obtained recombination profiles need to be integrated with an optical model describing the local outcoupling efficiency of the generated light. In this work, combined electrical and optical model calculations are presented, demonstrating that the light‐outcoupling efficiency in PLEDs is governed by the presence of electron traps and the anisotropy factor of optical dipoles. Electron trapping confines the recombination in a region close to cathode, resulting in strong optical trapping in surface plasmon polariton modes. Trap‐filling leads to a voltage‐dependent recombination profile and optical outcoupling efficiency. For a typical electron trap density of ≈1023 m−3, the calculated outcoupling efficiency raises from 5.5% at 2 V to 10.4% at 5 V in case of isotropic emitters. For conjugated polymers such as super yellow poly(p‐phenylene vinylene) with the chains preferentially aligned in the plane of the film, the outcoupling efficiency can reach ≈18% at 5 V. Elimination of electron trapping would allow for a further enhancement up to 24%.
Extensive Screening of Solvent‐Linked Porous Polymers through Friedel–Crafts Reaction for Gas Adsorption
Authors: Rozyyev Vepa , Hong Yeongran , Yavuz Mustafa S. , Thirion Damien , Yavuz Cafer T.
Published: May 2021

Scalability, cost, and feasibility of porous structures in gas capture are prerequisites for emerging materials to be promising in the industry. Herein, a simpler variant of Friedel−Crafts’ synthesis of highly porous covalent organic polymers (COPs) based on an unprecedented solvent‐mediated crosslinking is presented. Alkyl chlorides behave as both solvents and linkers in the presence of AlCl3. Studies on three classes of 18 different monomers using dichloromethane, chloroform, and 1,2‐dichloroethane lead to producing 29 new COPs (124−152). Polymers are characterized by Fourier‐transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR) spectroscopy, elemental composition analysis, scanning electron microscope (SEM), thermogravimetric analysis (TGA), and porosity analyzer. The synthesized COPs exhibit structures from nonporous to highly porous morphologies with Brunauer–Emmett–Teller (BET) surface areas as high as 1685 m2 g−1. These COPs show high gas uptake toward CO2 (up to 4.71 mmol g−1 at 273 K, 1.1 bar), CH4 (up to 1.31 mmol g−1 at 273 K, 1.1 bar), and H2 (up to 2.02 wt% at 77 K, 1.1 bar). The findings point to significant potential in producing sustainable porous materials through simple and scalable methodology developed here.
Numerical simulation of atomic layer deposition for thin deposit formation in a mesoporous substrate
Authors: Zhuang Liwei , Corkery Peter , Lee Dennis T. , Lee Seungjoon , Kooshkbaghi Mahdi , Xu Zhen‐liang , Dai Gance , Kevrekidis Ioannis G. , Tsapatsis Michael
Published: May 2021

ZnO deposition in porous γ‐Al2O3 via atomic layer deposition (ALD) is the critical first step for the fabrication of zeolitic imidazolate framework membranes using the ligand‐induced perm‐selectivation process (Science, 361 (2018), 1008–1011). A detailed computational fluid dynamics (CFD) model of the ALD reactor is developed using a finite‐volume‐based code and validated. It accounts for the transport processes within the feeding system and reaction chamber. The simulated precursor spatiotemporal profiles assuming no ALD reaction were used as boundary conditions in modeling diethylzinc reaction/diffusion in porous γ‐Al2O3, the predictions of which agreed with experimental electron microscopy measurements. Further simulations confirmed that the present deposition flux is much less than the upper limit of flux, below which the decoupling of reactor/substrate is an accurate assumption. The modeling approach demonstrated here allows for the design of ALD processes for thin‐film membrane formation including the synthesis of metal–organic framework membranes.
A spatially resolved model for pressure filtration of edible fat slurries
Authors: Van den Akker Harry E. A. , Hazelhoff Heeres Doedo P. , Kloek William
Published: May 2021

A spatially resolved one dimensional pressure filtration model was developed for a slurry of edible fat crystals. The model focuses on the expression step in which a cake is compressed to force the liquid through a filter cloth. The model describes the local oil flow in the shrinking cake modeled as a porous nonlinear elastic medium existing of two phases, viz. porous aggregates and interaggregate liquid. Conservation equations lead to a set of two differential equations (vs. time and vs. a material coordinate ω) for two void ratios, which are solved numerically by exploiting a finite‐difference scheme. A simulation with this model results in a spatially resolved cake composition and in the outflow velocity, both as a function of time, as well as the final solid fat contents of the cake. Simulation results for various filtration conditions are compared with experimental data collected in a pilot‐plant scale filter press.
Copper‐Catalyzed Decarboxylative Synthesis of α‐Ketothioamides Using α,β‐Unsaturated Arylcarboxylic Acids, Alicyclic Secondary Amines and Elemental Sulfur
Authors: Jaiswal Anjali , Sharma Anup Kumar , Preeti  , Singh Krishna Nand
Published: May 2021

An efficient and straightforward synthesis of α‐ketothioamides has been accomplished via in situ decarboxylative oxidative thioamidation using α,β‐unsaturated arylcarboxylic acids, alicyclic secondary amines and elemental sulfur under solvent‐free aerobic conditions.
DBU‐Catalyzed Regioselective α‐Alkylation of Enones Using the Vinylogous Strategy
Authors: Tian Yawei , Shang Yaping , Su Weiping
Published: May 2021

A convenient and atom‐economic transformation of enones with electron‐deficient alkenes under mild conditions has been developed using DBU as a catalyst. This method utilizes vinylogous strategy to form dienolate intermediates, which provides a new approach for the regioselective α‐alkylation of enones. This protocol exhibits a broad range of substrate scope and good functional group compatibility. Moreover, it enabled the formation of unexpected cyclic 1,5‐diketone by employing phenyl acrylate as Michael acceptor to construct all‐carbon quaternary centers at γ‐position of enones. Overall, this synthetic method establishes a new route from readily available enones to valuable 1,5‐dicarbonyl compounds.
Synthese und mehrfache Folgereaktivität von anionischen cyclo‐E3‐Ligandkomplexen (E=P, As)
Authors: Piesch Martin , Reichl Stephan , Seidl Michael , Balázs Gábor , Scheer Manfred
Published: May 2021

Ein synthetischer Zugang zur Synthese neuartiger anionischer Sandwichkomplexe mit einem cyclo‐E3‐Liganden (E=P, As) als Enddeck wurde entwickelt, der [Cp′′′Co(η3‐E3)]− (Cp′′′=1,2,4‐Tri‐tert‐butylcyclopentadienyl; E=P ([5]), As ([6])) in guten Ausbeuten ergibt und damit diese für weitere Reaktivitätsstudien geeignet macht. In der Reaktion mit den Chlorophosphanen R2PCl (R=Ph, Cy, tBu) wurden neutrale Komplexe mit einem zweifach substituierten cyclo‐E3P‐Liganden (E=P, As) in [Cp′′′Co(η3‐E3PR2)] (E=P (7 a–c), As (9 a–c)) erhalten. Diese Verbindungen können teilweise oder vollständig in Komplexe mit einem cyclo‐E3‐Liganden mit einer exocyclischen {PR2}‐Einheit in [Cp′′′Co(η2:η1‐E3PR2)] (E=P (8 a–c), As (10 a–c)) transferiert werden. Darüber hinaus gelang es, das Chlorosilylen [LSiCl] (L=(tBuN)2CPh) in den cyclo‐E3‐Liganden von [5] und [6] zu insertieren und die neuartigen heteroatomaren Komplexe [Cp′′′Co(η3‐E3SiL)] (E=P (11), As (12)) zu isolieren. Der Reaktionsweg konnte durch DFT‐Rechnungen aufgeklärt werden.
Unprecedented Noncanonical Features of the Nonlinear Nonribosomal Peptide Synthetase Assembly Line for WS9326A Biosynthesis
Authors: Kim Myoun‐Su , Bae Munhyung , Jung Ye‐Eun , Kim Jung Min , Hwang Sunghoon , Song Myoung Chong , Ban Yeon Hee , Bae Eun Seo , Hong Suckchang , Lee Sang Kook , Cha Sun‐Shin , Oh Dong‐Chan , Yoon Yeo Joon
Published: May 2021

Systematic inactivation of nonribosomal peptide synthetase (NRPS) domains and translocation of the thioesterase (TE) domain revealed several unprecedented nonlinear NRPS assembly processes during the biosynthesis of the cyclodepsipeptide WS9326A in Streptomyces sp. SNM55. First, two sets of type ΙΙ TE (TEΙΙ)‐like enzymes mediate the shuttling of activated amino acids between two sets of stand‐alone adenylation (A)‐thiolation (T) didomain modules and an “A‐less” condensation (C)‐T module with distinctive specificities and flexibilities. This was confirmed by the elucidation of the affinities of the A‐T didomains for the TEΙΙs and its structure. Second, the C‐T didomain module operates iteratively and independently from other modules in the same protein to catalyze two chain elongation cycles. Third, this biosynthetic pathway includes the first example of module skipping, where the interpolated C and T domains are required for chain transfer.
Response to “What Shall We Do with Computed Detonation Performance? Comment on ‘1,3,4‐Oxadiazole Bridges: A Strategy to Improve Energetics at the Molecular Level’”
Authors: Ma Jinchao , Chinnam Ajay Kumar , Cheng Guangbin , Yang Hongwei , Zhang Jiaheng , Shreeve Jean'ne M.
Published: May 2021

The values obtained for detonation performance are a function of the computational methods utilized. Since there are many such methods, the literature may contain a range of values for a single compound.
Enhancing Thermocatalytic Activities by Upshifting the d‐Band Center of Exsolved Co‐Ni‐Fe Ternary Alloy Nanoparticles for the Dry Reforming of Methane
Authors: Joo Sangwook , Kim Kyeounghak , Kwon Ohhun , Oh Jinkyung , Kim Hyung Jun , Zhang Linjuan , Zhou Jing , Wang Jian‐Qiang , Jeong Hu Young , Han Jeong Woo , Kim Guntae
Published: May 2021

Dry reforming of methane (DRM) is a feasible solution to address the reduction of greenhouse gases stipulated by the Paris Climate Agreement, given that it adds value by converting trivial gases, CO2 and CH4, simultaneously into useful syngas. However, the conventional Ni catalyst undergoes deactivation due to carbon coking and particle agglomeration. Here we demonstrate a highly efficient and durable DRM catalyst: exsolved Co‐Ni‐Fe ternary alloy nanoparticles on the layered perovskite PrBaMn1.7Co0.1Ni0.2O5+δ produced by topotactic exsolution. This method readily allows the generation of a larger number of exsolved nanoparticles with enhanced catalytic activity above that of Ni monometallic and Co‐Ni bimetallic particles. The enhancement is achieved by the upshift of the d‐band center of Co‐Ni‐Fe relative to those of Co‐Ni and Ni, meaning easier charge donation to the adsorbate. Furthermore, the exsolved catalyst shows exceptional stability, with continuous DRM operation for about 350 hours.
ZIF‐Based Nanoparticles Combine X‐Ray‐Induced Nitrosative Stress with Autophagy Management for Hypoxic Prostate Cancer Therapy
Authors: Li Yanli , Gong Teng , Gao Hongbao , Chen Yang , Li Huiyan , Zhao Peiran , Jiang Yaqin , Wang Kun , Wu Yelin , Zheng Xiangpeng , Bu Wenbo
Published: May 2021

Although reactive oxygen species (ROS)‐mediated tumor treatments are predominant in clinical applications, ROS‐induced protective autophagy promotes cell survival, especially in hypoxic tumors. Herein, X‐ray triggered nitrite (NO2−) is used for hypoxic prostate cancer therapy by inhibiting autophagy and inducing nitrosative stress based on an electrophilic zeolitic imidazole framework (ZIF‐82‐PVP). After internalization of pH‐responsive ZIF‐82‐PVP nanoparticles, electrophilic ligands and Zn2+ are delivered into cancer cells. Electrophilic ligands can not only consume GSH under hypoxia but also capture low‐energy electrons derived from X‐rays to generate NO2−, which inhibits autophagy and further elevates lethal nitrosative stress levels. In addition, dissociated Zn2+ specifically limits the migration and invasion of prostate cancer cells through ion interference. In vitro and in vivo results indicate that ZIF‐82‐PVP nanoparticles under X‐ray irradiation can effectively promote the apoptosis of hypoxic prostate cancer cells. Overall, this nitrosative stress‐mediated tumor therapy strategy provides a novel approach targeting hypoxic tumors.
Altering Hydrogenation Pathways in Photocatalytic Nitrogen Fixation by Tuning Local Electronic Structure of Oxygen Vacancy with Dopant
Authors: Bo Yanan , Wang Haiyun , Lin Yunxiang , Yang Tian , Ye Run , Li Yu , Hu Canyu , Du Pengye , Hu Yangguang , Liu Zhi , Long Ran , Gao Chao , Ye Bangjiao , Song Li , Wu Xiaojun , Xiong Yujie
Published: May 2021

To avoid the energy‐consuming step of direct N≡N bond cleavage, photocatalytic N2 fixation undergoing the associative pathways has been developed for mild‐condition operation. However, it is a fundamental yet challenging task to gain comprehensive understanding on how the associative pathways (i.e., alternating vs. distal) are influenced and altered by the fine structure of catalysts, which eventually holds the key to significantly promote the practical implementation. Herein, we introduce Fe dopants into TiO2 nanofibers to stabilize oxygen vacancies and simultaneously tune their local electronic structure. The combination of in situ characterizations with first‐principles simulations reveals that the modulation of local electronic structure by Fe dopants turns the hydrogenation of N2 from associative alternating pathway to associative distal pathway. This work provides fresh hints for rationally controlling the reaction pathways toward efficient photocatalytic nitrogen fixation.
A Synthetic Galectin Mimic
Authors: Timmer Brian J. J. , Kooijman Arjaan , Schaapkens Xander , Mooibroek Tiddo J.
Published: May 2021

Galectins are a galactoside specific subclass of carbohydrate binding proteins (lectins) involved in various cellular activities, certain cancers, infections, inflammations, and many other biological processes. The molecular basis for the selectivity of galectins is well‐documented and revolves around appropriate interaction complementarity: an aromatic residue for C−H⋅⋅⋅π interactions and polar residues for (charge assisted) hydrogen bonds with the axial hydroxyl group of a galactoside. However, no synthetic mimics are currently available. We now report on the design and synthesis of the first galectin mimic (6), and show that it has a higher than 65‐fold preference for n‐octyl‐β‐galactoside (8) over n‐octyl‐β‐glucoside (7) in CD2Cl2 containing 5 % [D6]DMSO (with Ka≥4500 M−1 for 6:8). Molecular modeling informed by nOe studies reveal a high degree of interaction complementarity between 6 and galactoside 8, which is very similar to the interaction complementarity found in natural galectins.
1,3‐Bis(tricyanoborane)imidazoline‐2‐ylidenate Anion—A Ditopic Dianionic N‐Heterocyclic Carbene Ligand
Authors: Zapf Ludwig , Radius Udo , Finze Maik
Published: May 2021

The 1,3‐bis(tricyanoborane)imidazolate anion 1 was obtained in high yield from lithium imidazolate and B(CN)3−pyridine adduct. Anion 1 is chemically very robust and thus allowed the isolation of the corresponding H5O2+ salt. Furthermore, monoanion 1 served as starting species for the novel dianionic N‐heterocyclic carbene (NHC), 1,3‐bis(tricyanoborane)imidazoline‐2‐ylidenate anion 3 that acts as ditopic ligand via the carbene center and the cyano groups at boron. First reactions of this new NHC 3 with methyl iodide, elemental selenium, and [Ni(CO)4] led to the methylated imidazolate ion 4, the dianionic selenium adduct 5, and the dianionic nickel tricarbonyl complex 6. These NHC derivatives provide a first insight into the electronic and steric properties of the dianionic NHC 3. Especially the combination of properties, such as double negative charge, different coordination sites, large buried volume and good σ‐donor and π‐acceptor ability, make NHC 3 a unique and promising ligand and building block.
Evaluation of micropillar array columns for chromatographic separation of phosphorothioated oligonucleotides and their diastereomers
Authors: Dillen Lieve , Deschrijver Tiny , Van Mol Kurt , Op de Beeck Jeff , Jacobs Paul , Cuyckens Filip
Published: May 2021

Chromatographic analysis of therapeutic oligonucleotides is challenging due to the presence of closely related impurities, degradants or metabolites and due to the presence of phosphorothioate bonds, which introduce chiral centers. In the present study, ion pair reversed phase chromatography of oligonucleotides on micropillar array columns was investigated. Two commonly used mobile phase conditions were included. With 16.3 mM triethylamine and 400 mM hexafluoroisopropanol, the separation of 16‐mer oligonucleotides differing in the number and positions of phosphorothioate linkages as well as some n‐1 and n‐2 truncations demonstrated complete suppression of diastereoselectivity. Although the positional phosphorothioate isomers evaluated could not be resolved, an increase in phosphorothioate bonds resulted in more retention. A therapeutic 19‐mer RNA sequence with 2′‐fluor and 2′‐O‐methyl modifications showed partial separation of some very close impurities. When using 15 mM triethyl ammonium acetate in the mobile phase, diastereomer selectivity was clearly observed for all analytes. The best result was obtained for the 19‐mer RNA therapeutic mimic with four phosphorothioate bonds, since all 16 theoretical diastereomers were clearly observed under the conditions tested. A limited benchmark exercise demonstrated the improved capability of the new micropillar array columns. Therefore, these columns can be positioned as a valuable alternative when challenging oligonucleotide separations are expected.
Polymer melting temperatures and crystallinity at different pressure applied
Authors: Chen Kailin , Zhang Wenshuo , Yarin Alexander L. , Pourdeyhimi Behnam
Published: May 2021

The present work aims at the experimental investigation of the effect of an increased thermal bonding pressure on the melting point (the so‐called Clapeyron effect) of three polymers employed in nonwovens. Namely, this work quantifies the dependence of melting temperature on pressure in these polymers. The following three polymers were used in the present experiments: polybutylene terephthalate (PBT), polyethylene terephthalate (PET), and polypropylene (PP) (all three already received in the form of nonwovens). A simple novel method of measurements of melting points of such polymers under different pressures was proposed and developed. The results revealed: (i) the melting point of PBT nonwovens increased by about 12°C when the applied pressure was increased up to 277.79 atm; (ii) the melting point of the PET nonwovens increased by about 7°C when the applied pressure increased up to 104.86 atm; (iii) the melting point of PP nonwovens increased by about 6°C when the applied pressure was increased up to 104.86 atm. The melting temperature measurements by the present method were also validated through differential scanning calorimetry measurements with the above‐mentioned three polymers without applied pressure.
Synthesis and characterization of biobased polyester PVC plasticizers to industrial manufacturing of tubes
Authors: Fernandes Mónica C. S. , Pereira Vanessa A. , Fonseca Ana C. , Ramalho Amílcar , Coelho Jorge F. J. , Barros Rodrigo , Pereira Paula , Pereira João , Serra Arménio C.
Published: May 2021

The search for the substitution of phthalate derivatives in the process of polyvinyl chloride (PVC) plasticization is a matter of intensive research, due to the increasing proofs about phthalate toxicity. With this objective, a series of novel saturated polyesters (SPs) were synthesized by polycondensation from different biobased acids and diols, and end‐capped with 2‐tetradecyloctadecan‐1‐ol (TDOD). After characterization, the SPs were incorporated in an industrial formulation for flexible PVC and the mechanical properties of the films analyzed by tensile tests, DMTA, and DSC. The tensile tests revealed a similar ultimate tensile strength and a higher elongation at break for the PVC with SP as plasticizers compared with DEHTP (di[2‐ethylhexyl] terephthalate). The SP showing the most promising results was chosen to carry on an industrial manufacturing of a transparent tube. The migration tests of the tube show a much less leaching properties compared with tube prepared using the plasticizer DEHTP. All the results indicate that SPs can be an industrially viable and excellent alternative to DEHTP.
Core‐shell structured BaTiO3@SiO2@PDA for high dielectric property nanocomposites with ultrahigh energy density
Authors: Wang Rui , Xie Congzhen , Gou Bin , Xu Huasong , Luo Shoukang , Du Yan , Zhou Jiangang , Yang Hao
Published: May 2021

Flexible nanocomposite dielectrics with high dielectric constant and discharge energy density have broad application prospects in the field of energy storage. However, dielectrics with high dielectric constant tend to have a high dielectric loss. Herein, we prepared a dielectric composite material with ultra‐high discharge energy density by modifying the interface between nanoparticles and poly(vinylidene fluoride‐co‐hexafluoropropylene) (P[VDF‐HFP]). After coating a shell of insulating amorphous SiO2 (~7 nm) outside the barium titanate (BT), the electric field concentration and current density inside BT particles can be significantly reduced. In addition, coating the SiO2 shell with a polydopamine (PDA) shell (~7 nm) not only enhances the interface interaction between the nanoparticles and the polymer matrix, but also can form lots of microcapacitors in the composite. As a result, an ultra‐high discharge energy density of 13.78 J/cm3 at the expense of relatively inconspicuous efficiency (~59.8%) in the BT@SiO2@PDA/P (VDF‐HFP) with 2.5 wt% loading has been achieved under 460 kV/mm. This is mainly attributed to the increases of dielectric constant from 12.1 to 14.2 and the relatively low dielectric loss (0.086) at 100 Hz. Moreover, compared with the pure P (VDF‐HFP) (400 kV/mm), the breakdown voltage of the composite with 2.5 wt% loading is surged to 460 kV/mm, which benefited from the hindrance of nanoparticles on carrier migration at low content. This work has realized a thin‐film dielectric with ultra‐high discharge energy density through a novel design of the nanoparticle structure, providing a theoretical direction for the development of polymer dielectric capacitors.
Effect of silane coupling on the properties of polylactic acid/barium ferrite magnetic composite filament for the 3D printing process
Authors: Sukthavorn Kankavee , Phengphon Natkritta , Nootsuwan Nollapan , Jantaratana Pongsakorn , Veranitisagul Chatchai , Laobuthee Apirat
Published: May 2021

Poly(lactic acid) (PLA)/barium ferrite (BaFe12O19) with different composition ratios was fabricated by magnetic composite filaments using an extrusion process for a 3D printer. The silane modified surface of BaFe12O19 was studied to observe the effect on the mechanical, morphology, thermal, and magnetic properties of magnetic composite filaments. The results showed that the silane treated surface BaFe12O19 not only enhanced the mechanical properties of magnetic composite filaments, but also improved adhesion and homogeneity between the BaFe12O19 filler and PLA matrix. Moreover, the thermal and magnetic properties of magnetic composite filaments were not obviously changed after adding silane treated surface BaFe12O19. The achievement of the magnetic composite filaments preparation with silane treated surface BaFe12O19 for the 3D printing process could become a guideline to develop and design other magnetic composites products in the near future.
Characterization of wood‐filled thermoplastic polyurethanes for the injection molding process
Authors: Moritzer Elmar , Richters Maximilian
Published: May 2021

Fiber fillings of wood plastic composites (WPC) are almost exclusively limited to standard plastics such as polyethylene and polypropylene. At the Kunststofftechnik Paderborn of the University of Paderborn the wood fiber filling of engineering plastics is being promoted. WPC with different fiber types and fiber contents based on two thermoplastic polyurethanes (TPU) were compounded and subsequently characterized. We found that the physicochemical properties of the materials differ from standard plastic‐based WPC. Wood filling with increasing fiber content did not immediately correlate with an increase in density. A decrease in density and swelling of the compound was detected with reaching a critical fiber content. Our compounds showed an increased water absorption at high‐fiber contents over time, which can be described logarithmically. The observed viscosity curves obey the Ostwald and de Waele power law, but an increased viscosity at increased fiber content was not apparent for both TPU matrices.
Study of the capacity of poly(N‐vinylcarbazole) derivatives to form honeycomb‐like patterns
Authors: Bekkar Fadila , Bettahar Faiza , Meghabar Rachid , Hamadouche Mohammed , Moreno‐Benitez Isabel , Vilas‐Vilela José Luis , Ruiz‐Rubio Leire
Published: May 2021

Poly(N‐vinylcarbazole), two dihalogenated derivatives, and nanocellulose/poly(N‐vinylcarbazole) nanocomposite thin films have been fabricated with micrometric pore topography. This patterned structure has been developed by using breath figure method, which is an easy and cost‐effective method to obtain honeycomb‐like arrays. In addition, the effect of the dihalogenated substitutions and the presence of nanocellulose fillers in the topography and conformational entropy were evaluated. The conformational entropy of each sample was calculated by using Voronoi tessellation. It is important to notice that highly regular patterns have been obtained from this photoconductive polymer, since the conductivity of this kind of material is proportional to the absorbed light, this honeycomb‐like topography could improve the light capture and the efficiency of photoelectric conversion, increasing the potential applicability of these materials.
Dual epigallocatechin gallate and camptothecin loaded electrospun meshes for synergy combination chemotherapy of colon cancer
Authors: Duan Lian , Yang Xiao , Ma Ya , Wu Jiaxue , Zou Yushan , Xiao Bo , Yi Shixiong
Published: May 2021

Combination chemotherapy based on electrospun fibrous was a promising strategy to applied synergy effects in treatment for colon cancer. Herein, Lactic acid/glycolic acid (PLGA) meshes with different ratios of epigallocatechin gallate (EGCG) and camptothecin (CPT) were manufactured. Results of X‐ray diffraction (XRD) revealed both EGCG and CPT were amorphous in meshes. Drug release experiments indicated that EGCG and CPT could be released sustainably while the dual drug‐loaded meshes had a higher release rate than single drug‐loaded meshes. Importantly, these meshes displayed obvious cytotoxicity against CT‐26 cells in anti‐colon cancer experiments, and the combination index values of all dual drug‐loaded meshes were around 0.5, suggesting strong synergy effect of EGCG and CPT. These results showed dual EGCG and CPT loaded meshes had application potential in effective synergistic therapy for colon cancer.
Digital Feast and Physical Famine: The Altered Ecosystem of Anatomy Education due to the Covid‐19 Pandemic
Authors: Baptiste Yvonne M.
Published: May 2021

This article explores the effects of the coronavirus disease 2019 (Covid‐19) pandemic on the evolution of both physical and digital cadavers within the unique ecosystem of the anatomy laboratory. A physical cadaver is a traditional and established learning tool in anatomy education, whereas a digital cadaver is a relatively recent phenomenon. The Covid‐19 pandemic presented a major disturbance and disruption to all levels and types of education, including anatomy education. This article constructs a conceptual metaphor between a typical anatomy laboratory and an ecosystem, and considers the affordances, constraints, and changing roles of physical and digital cadavers within anatomy education through an ecological lens. Adaptation of physical and digital cadavers during the disturbance is analyzed, and the resiliency of digital cadaver technology is recognized. The evolving role of the digital cadaver is considered in terms of increasing accessibility and inclusivity within the anatomy laboratory ecosystem of the future.
Traffic flow and emissions improvement via Vehicle‐to‐vehicle and vehicle‐to‐infrastructure communication for an intelligent intersection
Authors: Namazi Hosna , Taghavipour Amir
Published: May 2021

As transportation becomes more demanding in modern communities, the challenges involved such as congestion and emissions grow more concerns. Intelligent transportation system (ITS) is one of the most recognizable solution to resolve the problem. One of the components of an ITS is intelligent intersections that use vehicle‐to‐vehicle (V2V) and vehicle‐to‐infrastructure (V2I) communications to reduce the waiting time and consequently the idling time and emission of the vehicles. To implement different control strategies to reach the aforementioned objectives, a validated platform is required to simulate the real‐world traffic flow. To this end, Simulation of Urban Mobility (SUMO) software along with real data are utilized for developing two control strategies: Single Vehicle Speed Advisory Algorithm (SVSAA) and Platoon Speed Advisory Algorithm (PSAA). The results of real‐world simulation demonstrate that the proposed schemes are able to reduce the waiting time, fuel consumption, and emissions significantly compared with the baseline strategy. Moreover, it turns out that PSAA scheme implementation via model predictive controller may totally eliminate the congestion at the intersection.
A moment matching method for option pricing under stochastic interest rates
Authors: Antonelli Fabio , Ramponi Alessandro , Scarlatti Sergio
Published: May 2021

In this paper, we present a new and straightforward approximation methodology for pricing a call option in a Black and Scholes market, characterized by stochastic interest rates. The method relies on a Gaussian moment matching technique applied to a conditional Black and Scholes formula, used to disentangle the distributional complexity of the underlying price process. The problem then reduces to exploiting the Gaussian density and the expression of the bond price induced by the interest rate. To check its accuracy and computational time, we implement it for a CIR interest rate model correlated with the underlying, using Monte Carlo simulations as a benchmark. The method performance turns out to be quite remarkable, even when compared with similar results obtained by the affine approximation technique presented in Grzelak and Oosterlee, and by the expansion formula introduced in Kim and Kunimoto. In the last section, we apply the method also to the pricing of Forward‐Starting options, to the evaluation of the credit spreads in the Merton structural approach to credit risk, and we outline a possible application to a stochastic volatility model.
Production of extracellular enzymes by a termite‐nest‐related Bacillus siamensisYC‐9 in solid‐state fermentation on agricultural by‐products
Authors: Wang Junyong , Zhou Lingfeng , Yin Caiping , Gui Lin , Bao Liyun , Wu Fei , Zhang Yunhua , Zhang Yinglao
Published: May 2021

A Bacillus siamensis YC‐9 strain was isolated from termite nest. The strain was used to produce several important industrial enzymes by utilizing different agricultural by‐products with solid‐state fermentation (SSF). It was observed that most of the substrates that were studied were strongly positively affected by alkaline treatment for the production of enzymes. The highest yields for protease, α‐amylase, and cellulase were 82.87, 42.81, and 1.54 IU g−1, achieved on alkaline‐treated corn pericarp, rice bran, and wheat bran respectively. However, untreated soybean meal was the best choice for the secretion of pectinases (66.65 IU g−1). In general, ultrasonic pretreatment was more effective than microwave treatment and it promoted the production of proteases on soybean meal, sunflower meal, and wheat bran. The findings of the present study will provide some theoretical basis for enzyme production in the future. © 2021 Society of Industrial Chemistry and John Wiley & Sons Ltd.
Woodchip impregnation with weak white liquor and its effect in mitigating operational costs and environmental impacts in Kraft pulp mills
Authors: Johakimu Jonas K. , Sithole Bruce B.
Published: May 2021

Woodchip impregnation plays a vital role in enhancing Kraft pulp mill's pulping efficiency. Traditionally, Kraft pulp mills uses the mill's self‐generated liquor such as black liquor, green liquor, and white liquor. However, all these liquors have operational and / or pulping efficiency limitations. In this study, the feasibility of using weak white liquor as an alternative source of mill's self‐generated alkaline liquor for impregnating woodchips was investigated. South African Eucalyptus grandis woodchips were impregnated with and without weak white liquor. Under optimal conditions, the results showed that woodchips impregnated with weak white liquor responded much faster than the non‐impregnated ones (control). To maintain the same pulp and paper properties as the control pulp samples, a 20% reduction in the amount of cooking liquor used is required. When the experimental data were used to ascertain the economic and environmental benefits at an industrial mill scale, the savings in steam demand in the digester plant were estimated to be 23%. Energy savings in the lime kiln would be about 124 000 GJ per year. The reduction in carbon dioxide emissions in the calcination process was about 20%. Kraft pulp mills can use the information acquired in this study to determine whether this concept can be implemented in their commercial process. © 2021 Society of Chemical Industry and John Wiley & Sons, Ltd
Rapid and low‐cost sampling for detection of airborne SARS‐CoV‐2 in dehumidifier condensate
Authors: Moitra Parikshit , Alafeef Maha , Dighe Ketan , Ray Priyanka , Chang James , Thole Aaron , Punshon‐Smith Benjamin , Tolosa Michael , Ramamurthy Sai Sathish , Ge Xudong , Frey Douglas D. , Pan Dipanjan , Rao Govind
Published: May 2021

Airborne spread of coronavirus disease 2019 (COVID‐19) by infectious aerosol is all but certain. However, easily implemented approaches to assess the actual environmental threat are currently unavailable. We present a simple approach with the potential to rapidly provide information about the prevalence of severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) in the atmosphere at any location. We used a portable dehumidifier as a readily available and affordable tool to collect airborne virus in the condensate. The dehumidifiers were deployed in selected locations of a hospital ward with patients reporting flu‐like symptoms which could possibly be due to COVID‐19 over three separate periods of one week. Samples were analyzed frequently for both virus envelope protein and SARS‐CoV‐2 RNA. In several samples across separate deployments, condensate from dehumidifiers tested positive for the presence of SARS‐CoV‐2 antigens as confirmed using two independent assays. RNA was detected, but not attributable to SARS‐CoV‐2. We verified the ability of the dehumidifier to rapidly collect aerosolized sodium chloride. Our results point to a facile pool testing method to sample air in any location in the world and assess the presence and concentration of an infectious agent to obtain quantitative risk assessment of exposure, designate zones as “hot spots” and minimize the need for individual testing which may often be time consuming, expensive, and laborious.
Blood lead levels and lung cancer mortality: An updated analysis of NHANES II and III
Authors: Rhee Jongeun , Graubard Barry I. , Purdue Mark P.
Published: May 2021

Previous analyses within the National Health and Nutrition Examination Survey (NHANES) II and III cycles suggested an association between blood lead levels (BLLs) and lung cancer mortality, although the evidence was limited by small case numbers. To clarify this relationship, we conducted updated analyses of 4,182 and 15,629 participants in NHANES II and III, respectively, (extending follow‐up 20 and 8 years) aged ≥20 with BLL measurements and mortality follow‐up through 2014. We fit multivariable Cox models to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) relating BLLs and lung cancer with adjustment for smoking and other factors. We did not observe an overall association between BLLs and lung cancer after adjustment for smoking (both surveys) and serum cotinine and environmental tobacco smoke exposure (NHANES III), although suggestive associations were observed among women (NHANES II: HR 2.7, 95% CI 0.7, 10.0 for ≥20.0 µg/dl vs. <10.0 µg/dl, Ptrend = 0.07; NHANES III: HR 11.2, 95% CI 2.1, 59.4 for ≥10.0 µg/dl vs. <2.5 µg/dl, Ptrend = 0.04). After stratifying on smoking status, an association with elevated BLLs was observed in NHANES II only among former smokers (HR 3.2, 95% CI 1.3, 8.0 for ≥15 vs. <15 µg/dl) and in NHANES III only among current smokers (HR 1.7, 95% CI 1.1, 2.8 for ≥5 vs. <5 µg/dl).

In summary, we found elevated BLLs to be associated with lung cancer mortality among women in both NHANES II and III. Given the absence of an association among non‐smokers, we cannot rule out residual confounding as an explanation for our findings.
Utility of liquid‐based cytology on residual needle rinses collected from core needle biopsy for lung nodule diagnosis
Authors: Lan Zhihua , Zhang Xiaoli , Ma Xin , Hu Yiyan , Zhang Jing , Yang Fang
Published: May 2021

Background

Core needle biopsy (CNB) has become the most common tissue sampling modality for pathological diagnosis of peripheral lung nodules. However, approximately 10% of pulmonary CNB specimens cannot be unambiguously diagnosed, even with auxiliary techniques. This retrospective study investigated the diagnostic value of liquid‐based cytology on residual pulmonary CNB material collected from needle rinses.

Methods

Computed tomography‐guided pulmonary CNB specimens and relevant cytology of CNB needle rinses (CNR) from July 2017 to June 2020 were reviewed. A total of 406 patients, each of whom underwent a CNB procedure, were included in the study.

Results

Of the 406 cases, a more serious diagnosis was rendered by CNR in 6.4% (n = 26) of cases. Furthermore, among these 26 cases, 13 malignancies were confirmed only from CNR. Of the remaining 13 patients with uncertain lesions identified from CNR, six were diagnosed with definite benign lesions from tissue samples, five were found to harbor malignant neoplasms through repeated CNB or follow‐up examination, and two had tuberculosis. The sensitivity (320/332, 96.4%) of combined CNR/CNB (both CNR and CNB) in distinguishing malignancies from benign lesions was higher than that of CNB alone (307/332, 92.5%). A total of 320 malignant neoplasms included 198 cases of primary lung adenocarcinoma and 71 cases of primary lung squamous cell carcinoma.

Conclusions

CNR with higher nuclear and cytoplasmic resolution than CNB exhibited a high diagnostic efficacy for differentiating malignant from benign lesions in the lung. Moreover, combined CNR/CNB achieved optimal results in reducing the false‐negative rate and the subtyping of non‐small cell lung cancer.
Development and validation of MRI‐based deep learning models for prediction of microsatellite instability in rectal cancer
Authors: Zhang Wei , Yin Hongkun , Huang Zixing , Zhao Jian , Zheng Haoyu , He Du , Li Mou , Tan Weixiong , Tian Song , Song Bin
Published: May 2021

Background

Microsatellite instability (MSI) predetermines responses to adjuvant 5‐fluorouracil and immunotherapy in rectal cancer and serves as a prognostic biomarker for clinical outcomes. Our objective was to develop and validate a deep learning model that could preoperatively predict the MSI status of rectal cancer based on magnetic resonance images.

Methods

This single‐center retrospective study included 491 rectal cancer patients with pathologically proven microsatellite status. Patients were randomly divided into the training/validation cohort (n = 395) and the testing cohort (n = 96). A clinical model using logistic regression was constructed to discriminate MSI status using only clinical factors. Based on a modified MobileNetV2 architecture, deep learning models were tested for the predictive ability of MSI status from magnetic resonance images, with or without integrating clinical factors.

Results

The clinical model correctly classified 37.5% of MSI status in the testing cohort, with an AUC value of 0.573 (95% confidence interval [CI], 0.468 ~ 0.674). The pure imaging‐based model and the combined model correctly classified 75.0% and 85.4% of MSI status in the testing cohort, with AUC values of 0.820 (95% CI, 0.718 ~ 0.884) and 0.868 (95% CI, 0.784 ~ 0.929), respectively. Both deep learning models performed better than the clinical model (p < 0.05). There was no statistically significant difference between the deep learning models with or without integrating clinical factors.

Conclusions

Deep learning based on high‐resolution T2‐weighted magnetic resonance images showed a good predictive performance for MSI status in rectal cancer patients. The proposed model may help to identify patients who would benefit from chemotherapy or immunotherapy and determine individualized therapeutic strategies for these patients.
Experimental design optimization of simultaneous enantiomeric separation of atenolol and chlorthalidone binary mixture by high‐performance liquid chromatography using polysaccharide‐based stationary phases
Authors: Hassan Rasha M. , Saleh Ola A. , El‐Azzouny Aida A. , Aboul‐Enein Hassan Y. , Fouad Marwa A.
Published: May 2021

In this work, enantiomeric separation of a drug combination of two chiral drugs, namely, atenolol and chlorthalidone, is described. Prior investigation of the effect of different variables on the resolution of the enantiomers' peaks and the total run time represented by the retention time of the last eluted peak was conducted using face‐centered composite design. Twenty‐two experiments were carried out by varying the chiral stationary phase type as a categorical factor and mobile phase composition including the percentage of ethanol and percentage of diethylamine as continuous factors. According to the optimization process, a mobile phase consisting of hexane:ethanol:DEA:TFA (60:40:0.2:0.1%, v/v/v/v) pumped at flow rate 1 ml min−1 onto Lux‐Cellulose 2 stationary phase was applied for the chiral separation and quantification of the drug combination at 230 nm. Application of the developed method to the pharmaceutical formulation of this combination was successfully performed, and satisfactory percentage of recoveries was obtained. The method was also fully validated following International Conference on Harmonization (ICH) guidelines. This method could be of high value and relevance for application in quality control laboratories.
Life Cycle Analysis: Assessment of Technologies for Droplet Separation – A Case Study
Authors: Paschetag Mandy , Paschetag André , Merkel Florian , Mehringer Christian , Scholl Stephan
Published: May 2021

For the assessment of separation technologies from an ecological and economic perspective, a case study was performed to investigate the influence of entrainment on energy and resource demand of a single apparatus and on a single production process. Taking the example of the Rectisol process, the influence of droplet entrainment on individual separation equipment as well as on the process as a whole was identified via flowsheet simulation. Based on the calculated mass and energy balances, an LCA and LCC approach was used for the quantification of the entrainment influence.
Stereoselective Ring‐Opening Polymerization of rac‐Lactide Catalyzed by Squaramide Derived Organocatalysts at Room Temperature†
Authors: Jiang Xiao , Zhao Na , Li Zhibo
Published: May 2021

Main observation and conclusion

Substantial progresses have been made toward the development of metal‐free catalysts for stereoselective ring‐opening polymerization (ROP) of rac‐lactide. Yet the discovery of organic catalysts effective at ambient temperature remains a major challenge. Here, the bifunctional H‐bonding catalyst SQ‐1 containing a basic tertiary amine and squaramide motif proved to be good candidate for the stereoselective ROP of rac‐lactide at room temperature, yielding stereoregular polylactide with controlled molecular weights (up to 21.1 kg/mol) and high tacticity (PiESC up to 0.88). Furthermore, binary H‐bonding catalytic system consisting of squaramides (SQ‐2 to SQ‐6) and 1,8‐diazabicyclo[5.4.0]undec‐7‐ene (DBU) could efficiently promote the ROP of rac‐lactide at room temperature within short reaction time. Among them, the most bulky squaramide SQ‐2 exhibited the best steroselectivity towards the ROP of rac‐lactide without transesterification side reactions during the polymerization process. The resulting polylactides were proved to have controlled molecular weights as high as 22.2 kg/mol and narrow distributions (1.10—1.24).
A novel study on SARS‐COV‐2 virus associated bradycardia as a predictor of mortality‐retrospective multicenter analysis
Authors: Kumar Sabina , Arcuri Christina , Chaudhuri Sumanta , Gupta Rahul , Aseri Mahendra , Barve Pranav , Shah Shivang
Published: May 2021

Background

SARS‐CoV2 has affected more than 73.8 million individuals. While SARS‐CoV2 is considered a predominantly respiratory virus, we report a trend of bradycardia among hospitalized patients, particularly in association with mortality.

Methodology

The multi‐center retrospective analysis consisted of 1053 COVID‐19 positive patients from March to August 2020. A trend of bradycardia was noted in the study population. Absolute bradycardia and profound bradycardia was defined as a sustained heart rate < 60 BPM and < 50 BPM, respectively, on two separate occasions, a minimum of 4 h apart during hospitalization. Each bradycardic event was confirmed by two physicians and exclusion criteria included: less than 18 years old, end of life bradycardia, left AMA, or taking AV Nodal blockers. Data was fetched using a SQL program through the EMR and data was analyzed using SPSS 27.0. A logistic regression was done to study the effect of bradycardia, age, gender, and BMI on mortality in the study group.

Results

24.9% patients had absolute bradycardia while 13.0% had profound bradycardia. Patients with absolute bradycardia had an odds ratio of 6.59 (95% CI [2.83–15.36]) for mortality compared with individuals with a normal HR response. The logistic regression model explained 19.6% (Nagelkerke R2) of variance in the mortality, correctly classified 88.6% of cases, and was statistically significant X2 (5)=47.10, p < .001. For each year of age > 18, the odds of dying increased 1.048 times (95% CI [1.25–5.27]).

Conclusion

The incidence of absolute bradycardia was found in 24.9% of the study cohort and these individuals were found to have a significant increase in mortality.