bluuebunny/crossref_metadata_2025 huggingface dataset:
Oscillations of skyrmion clusters in Co/Pt multilayer nanodots
Authors: Tejo Felipe , Velozo Felipe , Elías Ricardo Gabriel , Escrig Juan
Published: October 2020

In this work we study the oscillations of the skyrmion cores in a multilayer nanodot as a function of the number of skyrmions hosted in the system. When all the skyrmions in the nanodot have the same core radius, and after applying a perpendicular spin-polarized current, a relaxation process takes place towards an equilibrium configuration that is accompanied by coherent damped oscillations of the skyrmion cores, whose frequency depends on the number of skyrmions present in the nanodot. Additionally, we found that the oscillation frequency is directly related to the total energy of the system.
The complete mitochondrial genome of medicinal fungus Taiwanofungus camphoratus reveals gene rearrangements and intron dynamics of Polyporales
Authors: Wang Xu , Jia Lihua , Wang Mingdao , Yang Hao , Chen Mingyue , Li Xiao , Liu Hanyu , Li Qiang , Liu Na
Published: October 2020

Taiwanofungus camphoratus is a highly valued medicinal mushroom that is endemic to Taiwan, China. In the present study, the mitogenome of T. camphoratus was assembled and compared with other published Polyporales mitogenomes. The T. camphoratus mitogenome was composed of circular DNA molecules, with a total size of 114,922 bp. Genome collinearity analysis revealed large-scale gene rearrangements between the mitogenomes of Polyporales, and T. camphoratus contained a unique gene order. The number and classes of introns were highly variable in 12 Polyporales species we examined, which proved that numerous intron loss or gain events occurred in the evolution of Polyporales. The Ka/Ks values for most core protein coding genes in Polyporales species were less than 1, indicating that these genes were subject to purifying selection. However, the rps3 gene was found under positive or relaxed selection between some Polyporales species. Phylogenetic analysis based on the combined mitochondrial gene set obtained a well-supported topology, and T. camphoratus was identified as a sister species to Laetiporus sulphureus. This study served as the first report on the mitogenome in the Taiwanofungus genus, which will provide a basis for understanding the phylogeny and evolution of this important fungus.
Enhanced asthma-related fibroblast to myofibroblast transition is the result of profibrotic TGF-β/Smad2/3 pathway intensification and antifibrotic TGF-β/Smad1/5/(8)9 pathway impairment
Authors: Wnuk Dawid , Paw Milena , Ryczek Karolina , Bochenek Grażyna , Sładek Krzysztof , Madeja Zbigniew , Michalik Marta
Published: October 2020

Airway remodelling with subepithelial fibrosis, which abolishes the physiological functions of the bronchial wall, is a major issue in bronchial asthma. Human bronchial fibroblasts (HBFs) derived from patients diagnosed with asthma display in vitro predestination towards TGF-β1-induced fibroblast-to-myofibroblast transition (FMT), a key event in subepithelial fibrosis. As commonly used anti-asthmatic drugs do not reverse the structural changes of the airways, and the molecular mechanism of enhanced asthma-related TGF-β1-induced FMT is poorly understood, we investigated the balance between the profibrotic TGF-β/Smad2/3 and the antifibrotic TGF-β/Smad1/5/9 signalling pathways and its role in the myofibroblast formation of HBF populations derived from asthmatic and non-asthmatic donors. Our findings showed for the first time that TGF-β-induced activation of the profibrotic Smad2/3 signalling pathway was enhanced, but the activation of the antifibrotic Smad1/5/(8)9 pathway by TGF-β1was significantly diminished in fibroblasts from asthmatic donors compared to those from their healthy counterparts. The impairment of the antifibrotic TGF-β/Smad1/5/(8)9 pathway in HBFs derived from asthmatic donors was correlated with enhanced FMT. Furthermore, we showed that Smad1 silencing in HBFs from non-asthmatic donors increased the FMT potential in these cells. Additionally, we demonstrated that activation of antifibrotic Smad signalling via BMP7 or isoliquiritigenin [a small-molecule activator of the TGF-β/Smad1/5/(8)9 pathway] administration prevents FMT in HBFs from asthmatic donors through downregulation of profibrotic genes, e.g., α-SMA and fibronectin. Our data suggest that influencing the balance between the antifibrotic and profibrotic TGF-β/Smad signalling pathways using BMP7-mimetic compounds presents an unprecedented opportunity to inhibit subepithelial fibrosis during airway remodelling in asthma.
Theory of optical tweezing of dielectric microspheres in chiral host media and its applications
Authors: Ali Rfaqat , Dutra Rafael S. , Pinheiro Felipe A. , Rosa Felipe S. S. , Maia Neto Paulo A.
Published: October 2020

We report for the first time the theory of optical tweezers of spherical dielectric particles embedded in a chiral medium. We develop a partial-wave (Mie) expansion to calculate the optical force acting on a dielectric microsphere illuminated by a circularly-polarized, highly focused laser beam. When choosing a polarization with the same handedness of the medium, the axial trap stability is improved, thus allowing for tweezing of high-refractive-index particles. When the particle is displaced off-axis by an external force, its equilibrium position is rotated around the optical axis by the mechanical effect of an optical torque. Both the optical torque and the angle of rotation are greatly enhanced in the presence of a chiral host medium when considering radii a few times larger than the wavelength. In this range, the angle of rotation depends strongly on the microsphere radius and the chirality parameter of the host medium, opening the way for a quantitative characterization of both parameters. Measurable angles are predicted even in the case of naturally occurring chiral solutes, allowing for a novel all-optical method to locally probe the chiral response at the nanoscale.
Berberine affects mitochondrial activity and cell growth of leukemic cells from chronic lymphocytic leukemia patients
Authors: Ravera Silvia , Ghiotto Fabio , Tenca Claudya , Gugiatti Elena , Santamaria Sara , Ledda Bernardetta , Ibatici Adalberto , Cutrona Giovanna , Mazzarello Andrea N. , Bagnara Davide , Cardillo Martina , Zarcone Daniela , Darzynkiewicz Zbigniew , Ciccone Ermanno , Fais Franco , Bruno Silvia
Published: October 2020

B-cell chronic lymphocytic leukemia (CLL) results from accumulation of leukemic cells that are subject to iterative re-activation cycles and clonal expansion in lymphoid tissues. The effects of the well-tolerated alkaloid Berberine (BRB), used for treating metabolic disorders, were studied on ex-vivo leukemic cells activated in vitro by microenvironment stimuli. BRB decreased expression of survival/proliferation-associated molecules (e.g. Mcl-1/Bcl-xL) and inhibited stimulation-induced cell cycle entry, irrespective of TP53 alterations or chromosomal abnormalities. CLL cells rely on oxidative phosphorylation for their bioenergetics, particularly during the activation process. In this context, BRB triggered mitochondrial dysfunction and aberrant cellular energetic metabolism. Decreased ATP production and NADH recycling, associated with mitochondrial uncoupling, were not compensated by increased lactic fermentation. Antioxidant defenses were affected and could not correct the altered intracellular redox homeostasis. The data thus indicated that the cytotoxic/cytostatic action of BRB at 10–30 μM might be mediated, at least in part, by BRB-induced impairment of oxidative phosphorylation and the associated increment of oxidative damage, with consequent inhibition of cell activation and eventual cell death. Bioenergetics and cell survival were instead unaffected in normal B lymphocytes at the same BRB concentrations. Interestingly, BRB lowered the apoptotic threshold of ABT-199/Venetoclax, a promising BH3-mimetic whose cytotoxic activity is counteracted by high Mcl-1/Bcl-xL expression and increased mitochondrial oxidative phosphorylation. Our results indicate that, while CLL cells are in the process of building their survival and cycling armamentarium, the presence of BRB affects this process.
New semi-analytical solution of the problem of vapor bubble growth in superheated liquid
Authors: Chernov A. A. , Pil’nik A. A. , Vladyko I. V. , Lezhnin S. I.
Published: October 2020

This paper presents a mathematical model of the vapor bubble growth in an initially uniformly superheated liquid. This model takes into account simultaneously the dynamic and thermal effects and includes the well-known classical equations: the Rayleigh equation and the heat conductivity equation, written with consideration of specifics associated with the process of liquid evaporation. We have obtained a semi-analytical solution to the problem, which consists in reducing the initial boundary value problem with a moving boundary to a system of ordinary differential equations of the first order, valid in a wide range of operating parameters of the process at all its stages: from inertial to thermal, including the transitional one. It is shown that at large times this solution is consistent with the known solutions of other authors obtained in the framework of the energy thermal model, in particular, for the high Jacob numbers, it is consistent with the Plesset–Zwick solution.
Characterization of the biofilm matrix composition of psychrotrophic, meat spoilage pseudomonads
Authors: Wickramasinghe Nirmani N. , Hlaing Mya M. , Ravensdale Joshua T. , Coorey Ranil , Chandry P. Scott , Dykes Gary A.
Published: October 2020

Psychrotrophic Pseudomonas species are the key spoilage bacteria of aerobically stored chilled meat. These organisms readily form biofilms on meat under refrigerated conditions leading to consumer rejection and associated economic losses. Limited information is available on the matrix composition of the biofilms formed by these bacteria. We quantified and characterized the main components of the matrix of mono-species biofilms of selected Pseudomonas fragi and Pseudomonas lundensis strains using chemical analysis and Raman spectroscopy. The biofilms were grown at 10 °C and 25 °C on nitro-cellulose membranes placed on surface sterilized beef cuts. Extra-cellular polymeric substances of the matrix were extracted in soluble and bound forms and were chemically assessed for total carbohydrates, proteins and extra-cellular DNA. Both Pseudomonas species showed a significant increase in total carbohydrates and total proteins when grown at 10 °C as compared to 25 °C. Extra-cellular DNA did not show a strong correlation with growth temperature. Raman spectra were obtained from planktonic bacteria and membrane grown biofilms at 10 °C and 25 °C. Higher levels of guanine were detected in planktonic cells as compared to biofilm cells. This study suggests that psychrotrophic Pseudomonas species may respond to cold stress by increasing extra-cellular polymer secretions.
Spred2-deficiency enhances the proliferation of lung epithelial cells and alleviates pulmonary fibrosis induced by bleomycin
Authors: Kawara Akina , Mizuta Ryo , Fujisawa Masayoshi , Ito Toshihiro , Li Chunning , Nakamura Kaoru , Sun Cuiming , Kuwabara Masaki , Kitabatake Masahiro , Yoshimura Teizo , Matsukawa Akihiro
Published: October 2020

The mitogen-activated protein kinase (MAPK) pathways are involved in many cellular processes, including the development of fibrosis. Here, we examined the role of Sprouty-related EVH-1-domain-containing protein (Spred) 2, a negative regulator of the MAPK-ERK pathway, in the development of bleomycin (BLM)-induced pulmonary fibrosis (PF). Compared to WT mice, Spred2−/− mice developed milder PF with increased proliferation of bronchial epithelial cells. Spred2−/− lung epithelial cells or MLE-12 cells treated with spred2 siRNA proliferated faster than control cells in vitro. Spred2−/− and WT macrophages produced similar levels of TNFα and MCP-1 in response to BLM or lipopolysaccharide and myeloid cell-specific deletion of Spred2 in mice had no effect. Spred2−/− fibroblasts proliferated faster and produced similar levels of MCP-1 compared to WT fibroblasts. Spred2 mRNA was almost exclusively detected in bronchial epithelial cells of naïve WT mice and it accumulated in approximately 50% of cells with a characteristic of Clara cells, 14 days after BLM treatment. These results suggest that Spred2 is involved in the regulation of tissue repair after BLM-induced lung injury and increased proliferation of lung bronchial cells in Spred2−/− mice may contribute to faster tissue repair. Thus, Spred2 may present a new therapeutic target for the treatment of PF.
High frequency acoustic cell stimulation promotes exosome generation regulated by a calcium-dependent mechanism
Authors: Ambattu Lizebona August , Ramesan Shwathy , Dekiwadia Chaitali , Hanssen Eric , Li Haiyan , Yeo Leslie Y.
Published: October 2020

Exosomes are promising disease diagnostic markers and drug delivery vehicles, although their use in practice is limited by insufficient homogeneous quantities that can be produced. We reveal that exposing cells to high frequency acoustic irradiation stimulates their generation without detriment to cell viability by exploiting their innate membrane repair mechanism, wherein the enhanced recruitment of calcium ions from the extracellular milieu into the cells triggers an ESCRT pathway known to orchestrate exosomal production. Given the high post-irradiation cell viabilities (≈95%), we are able to recycle the cells through iterative irradiation and post-excitation incubation steps, which facilitate high throughput production of a homogeneous population of exosomes—a particular challenge for translating exosome therapy into clinical practice. In particular, we show that approximately eight- to ten-fold enrichment in the number of exosomes produced can be achieved with just 7 cycles over 280 mins, equivalent to a yield of around 1.7–2.1-fold/h.
Explosives detection by swabbing for improvised explosive devices
Authors: Glackin James M. E. , Gillanders Ross N. , Eriksson Frans , Fjällgren Marcus , Engblom Joachim , Mohammed Salam , Samuel Ifor D. W. , Turnbull Graham A.
Published: October 2020

Swabs taken from the surface of a suspicious object are a standard method of identifying a concealed explosive device in security-conscious locations like airports. Light-emitting polymer sensors can detect trace amounts via fluorescence quenching.
A label-free photoelectrochemical immunosensor for carcinoembryonic antigen detection based on a g-C3N4/CdSe nanocomposite
Authors: Liu Xing-Pei , Chen Jing-Shuai , Mao Chang-Jie , Jin Bao-Kang
Published: October 2020

Herein, a label-free photoelectrochemical immunosensor based on a g-C3N4/CdSe nanocomposite was established and applied to detect carcinoembryonic antigen (CEA).
Light-accelerating oxidase-mimicking activity of black phosphorus quantum dots for colorimetric detection of acetylcholinesterase activity and inhibitor screening
Authors: Ren Lei , Li Hongdan , Liu Mei , Du Jianxiu
Published: October 2020

The exposure of 365 nm light irradiation significantly accelerates the oxidase-mimicking activity of black phosphorus quantum dots, allowing sensitive colorimetric assay of acetylcholinesterase activity and evaluation of its inhibitor screening.
Antibacterial photodynamic peptides for staphylococcal skin infection
Authors: Lei Xiaoling , Qiu Lin , Lan Min , Du Xuancheng , Zhou Shuwen , Cui Pengfei , Zheng Ronghui , Jiang Pengju , Wang Jianhao , Xia Jiang
Published: October 2020

A multicomponent system centered on antibacterial photodynamic peptides and supported by a regenerative gelatin–collagen (Gel–Col) hydrogel.
The structure-defining incorporation of chloride in methyllithium dimers
Authors: Knauer Lena , Strohmann Carsten
Published: October 2020

Two polymeric solid-state structures of pmdta-stabilized methyllithium with co-existing tetrameric and dimeric units were obtained, linked by the structure-giving “contaminant” LiCl, incorporated only in dimeric entities.
Copper and palladium co-catalyzed highly regio-selective 1,2-hydroarylation of terminal 1,3-dienes
Authors: Zhang Rumeng , Li Qifan , Zhang Min , Chai Sida , Duan Yuqi , Su Jingfei , Zhao Qian , Zhang Chun
Published: October 2020

The novel and practical copper and palladium co-catalyzed 1,2-hydroarylation of terminal 1,3-dienes by one step reaction has been developed, which could afford a kind of versatile precursor for organic synthesis.
On the reactivity of mRNA Cap0: C–H oxidative addition of 7-methylguanosine to Pt0 and base pairing studies
Authors: Leitão Maria Inês P. S. , Gonzalez Carmen , Francescato Giulia , Filipiak Zuzanna , Petronilho Ana
Published: October 2020

The first N-heterocyclic carbene ligand derived from 7-methylguanosine, mRNA cap0, has been prepared by C–H oxidative addition to a platinum(0) complex.
Hydrogen-bonded organic frameworks of twisted polycyclic aromatic hydrocarbon
Authors: Suzuki Yuto , Tohnai Norimitsu , Saeki Akinori , Hisaki Ichiro
Published: October 2020

A dibenzo[g,p]chrysene (DBC)-based hydrogen-bonded organic framework (HOF) possessing surface area of 1548 m2g−1and photoconductivity was constructed.
Remote-controlled regio- and diastereodifferentiating photodimerization of a dynamic helical peptide-bound 2-substituted anthracene
Authors: Taura Daisuke , Urushima Akio , Sugioka Yusuke , Ousaka Naoki , Yashima Eiji
Published: October 2020

Photodimerization of a right-handed 310-helical nonapeptide-bound 2-substituted anthracene produced the chiral head-to-head anti-photodimer with up to 97% diastereomeric excess.
Metal-encapsulation induces a highly regioselective Bingel–Hirsch reaction of the labile Y@Cs(6)-C82
Authors: Shen Wangqiang , Yang Le , Li Bo , Jin Peng , Yu Bing , Cong Hailin , Akasaka Takeshi , Lu Xing
Published: October 2020

The chemical properties of a prototypical labile mono-EMF, Y@Cs(6)-C82, have been systematically disclosed for the first time via a Bingel–Hirsch reaction.
Anisotropic properties and Raman spectra of a LiNa5Mo9O30 single crystal grown by the TSSG method
Authors: Du Xiaoli , Gao Zeliang , Liu Fuan , Guo Xiaojie , Wang Xiangmei , Sun Youxuan , Tao Xutang
Published: October 2020

Single crystal LiNa5Mo9O30 with 52 × 44 × 8 mm3 was successfully grown using the TSSG method. The transmission spectrum, thermal diffusion, thermal conductivity, and polarized Raman spectrum of a-cut configurations were systematically investigated.
Two sulfur and nitrogen-rich cobalt–thiacalix[4]arene compounds for the selective mercury removal from aqueous solutions
Authors: Li Kaiyue , Liao Wuping
Published: October 2020

Two thiacalix[4]arene-based coordination compounds, a {Co24} octahedral coordination cage and a {Co8} cluster, are effective adsorbents towards Hg(ii) and the adsorption capacity of the {Co24} cage compound reaches 330 mg g−1.
Nanosheet-assembled microflower-like coordination polymers by surfactant-assisted assembly with enhanced catalytic activity
Authors: Zhang Ying-Ying , Hu Mingjun , Lu Guizhen , Qin Na , Han Suzhen , Zhu Kaifang , Huang Chao , Mi Liwei
Published: October 2020

Nanosheet-assembled microflower-like coordination polymers were successfully prepared by a surfactant-assisted approach and used as an efficient heterogeneous catalyst to execute the conversion reactions of nitromethylbenzenes into benzoic acids.
Buckybowls as gas adsorbents: binding of gaseous pollutants and their electric-field induced release
Authors: Burrill Daniel J. , Lambrecht Daniel S.
Published: October 2020

The adsorption of nitric oxide and nitrogen dioxide (NOx) to the Buckybowls sumanene and corannulene was investigated.
Conformational topography of tris(2-methylbutyl) phosphate and the influence of methyl branching at the non-hyperconjugative carbon on the conformational landscape: insights from matrix isolation infrared spectroscopy and DFT computations
Authors: Sarkar Subramee , Chandra Swaroop , Suryaprasad B. , Ramanathan N. , Sundararajan K. , Suresh A.
Published: October 2020

Branching dramatically reduces the number of conformers of T2MBP relative to its straight chain analogue, while hyperconjugative effects stabilize 'gauche' over 'trans' form, energetically.
Emerging trends in the dynamics of polyelectrolyte complexes
Authors: Manoj Lalwani Suvesh , Eneh Chikaodinaka I. , Lutkenhaus Jodie L.
Published: October 2020

Polyelectrolyte complexes (PECs) exhibit varying dynamic responses depending upon the ionic strength, water content, temperature, pH, and molecular weight.
A two-dimensional h-BN/C2N heterostructure as a promising metal-free photocatalyst for overall water-splitting
Authors: Wang Guangzhao , Li Zongfeng , Wu Weikang , Guo Hao , Chen Cong , Yuan Hongkuan , Yang Shengyuan A.
Published: October 2020

A metal-free type-II h-BN/C2N heterostructure is shown as a potential visible light water-splitting photocatalyst.
Disclosing the microscopic mechanism and adsorption properties of CO2 capture in N-isopropylethylenediamine appended M2(dobpdc) series
Authors: Zhang Hui , Yang Li-Ming , Pan Hui , Ganz Eric
Published: October 2020

The detailed picture of the microscopic mechanism for CO2 capture with N-isopropylethylenediamine grafted M2(dobpdc) has been determined for the first time via systematic computations with vdW corrected density functional theory.
Dynamics of third order direct three-body recombination of heavy ions
Authors: Akimov Vyacheslav M. , Azriel' Vladimir M. , Ermolova Ekaterina V. , Kabanov Dmitrii B. , Kolesnikova Lyubov' I. , Rusin Lev Yu. , Sevryuk Mikhail B.
Published: October 2020

Dynamics of direct three-body recombination of cesium and fluoride (iodide) ions in the presence of argon (xenon) atoms is studied.
Dynamics of confined water and its interplay with alkali cations in sodium aluminosilicate hydrate gel: insights from reactive force field molecular dynamics
Authors: Lyngdoh Gideon A. , Kumar Rajesh , Krishnan N. M. Anoop , Das Sumanta
Published: October 2020

This paper presents the dynamics of confined water and its interplay with alkali cations in disordered sodium aluminosilicate hydrate (N-A-S-H) gel using reactive force field molecular dynamics.
Organic-based inverters: basic concepts, materials, novel architectures and applications
Authors: Leydecker Tim , Wang Zhiming M. , Torricelli Fabrizio , Orgiu Emanuele
Published: October 2020

The review article covers the materials and techniques employed to fabricate organic-based inverter circuits and highlights their novel architectures, ground-breaking performances and potential applications.
Gas diffusion electrode design for electrochemical carbon dioxide reduction
Authors: Nguyen Tu N. , Dinh Cao-Thang
Published: October 2020

Insightful guide to developing efficient gas diffusion electrodes for electrochemical CO2 conversion to fuels and chemicals.
Genetic alphabet expansion technology by creating unnatural base pairs
Authors: Kimoto Michiko , Hirao Ichiro
Published: October 2020

Recent advancements in the creation of artificial extra base pairs (unnatural base pairs, UBPs) are opening the door to a new research area, xenobiology, and genetic alphabet expansion technologies.
The first pentagonal-bipyramidal vanadium(iii) complexes with a Schiff-base N3O2pentadentate ligand: synthesis, structure and magnetic properties
Authors: Bazhenova Tamara A. , Zorina Leokadiya V. , Simonov Sergey V. , Mironov Vladimir S. , Maximova Olga V. , Spillecke Lena , Koo Changhyun , Klingeler Rüdiger , Manakin Yuriy V. , Vasiliev Alexander N. , Yagubskii Eduard B.
Published: October 2020

A series of three mononuclear pentagonal-bipyramidal V(iii) complexes with the equatorial pentadentate N3O2-ligand were synthesized and characterized structurally and magnetically.
Recent advances in nanostructured transition metal phosphides: synthesis and energy-related applications
Authors: Shi Yanmei , Li Mengyang , Yu Yifu , Zhang Bin
Published: October 2020

This review provides an overview of recent advances in the synthesis and diverse energy-related applications of nanostructured transition metal phosphides.
Calibration of boron isotope ratio measurements by MC-ICP-MS using normalisation to admixed internal standards
Authors: Malinovsky D. , Dunn P. J. H. , Goenaga-Infante H.
Published: October 2020

Online normalisation to isotope ratios of admixed internal standards is an important technique in isotopic analysis by multicollector ICP-MS (MC-ICP-MS).
White-light-emitting triphasic fibers as a phosphor for light-emitting diodes
Authors: Han Weidong , Chae Su-Hyeong , Kim Taewoo , Lee Daewoo , Kim Hakyong
Published: October 2020

White-light-emitting PSCR fibrous membranes were obtained via a triphasic electrospinning approach. The PSCR fibrous membrane was applied to a LED as a light conversion layer by remote packaging, and bright white light was obtained.
Magnetic and light-responsive nanogels based on chitosan functionalized with Au nanoparticles and poly(N-isopropylacrylamide) as a remotely triggered drug carrier
Authors: Pourjavadi Ali , Doroudian Mohadeseh , Bagherifard Mina , Bahmanpour Maryam
Published: October 2020

Synthesis of thermosensitive nanogels based on functionalized chitosan with Au nanoparticles (NPs) and poly(NIPAM) to release of drug molecules under light exposure.
Boosting glucose oxidation by constructing Cu–Cu2O heterostructures
Authors: Cao Kangzhe , Zhang Hang , Gao Zihui , Liu Yiyuan , Jia Yongheng , Liu Huiqiao
Published: October 2020

An octahedral Cu–Cu2O heterostructure with loose and porous structure was fabricated and exhibits enhanced electrocatalytic activity towards glucose oxidation.
Synthesis, characterization, and some properties of two types of new [Fe]-H2ase models containing a 4-phosphatopyridine or a 4-phosphatoguanosinepyridine moiety
Authors: Song Li-Cheng , Chen Wei , Zhu Liang , Hu Fu-Qiang , Jiang Kai-Yu
Published: October 2020

The novel [Fe]-H2ase active site framework-containing model 6 was first prepared and structurally characterized.
Correction: Photochemical reduction of Cr(vi) compounds by amino acid Schiff base copper complexes with a hydroxyl group and titanium oxide composites in aqueous solutions
Authors: Miyagawa Yoshito , Tsaturyan Arshak , Haraguchi Tomoyuki , Shcherbakov Igor , Akitsu Takashiro
Published: October 2020

Correction for ‘Photochemical reduction of Cr(vi) compounds by amino acid Schiff base copper complexes with a hydroxyl group and titanium oxide composites in aqueous solutions’ by Yoshito Miyagawa et al., New J. Chem., 2020, DOI: 10.1039/d0nj02481c.
Key considerations in designing CRISPR/Cas9-carrying nanoparticles for therapeutic genome editing
Authors: Xu Yunxue , Liu Renfa , Dai Zhifei
Published: October 2020

CRISPR-Cas9, the breakthrough genome-editing technology, has emerged as a promising tool to prevent and cure various diseases.
A structure and activity relationship for single-walled carbon nanotube growth confirmed by in situ observations and modeling
Authors: Chao Hsin-Yun , Jiang Hua , Ospina-Acevedo Francisco , Balbuena Perla B. , Kauppinen Esko I. , Cumings John , Sharma Renu
Published: October 2020

The structure and phase transformation of a cobalt (Co) catalyst, during single walled carbon nanotube (SWCNT) growth, is elucidated for inactive, active and deactivated nanoparticles by in situ imaging using an ETEM.
Correction: Dynamic magnetic characterization and magnetic particle imaging enhancement of magnetic-gold core–shell nanoparticles
Authors: Tomitaka Asahi , Ota Satoshi , Nishimoto Kizuku , Arami Hamed , Takemura Yasushi , Nair Madhavan
Published: October 2020

Correction for ‘Dynamic magnetic characterization and magnetic particle imaging enhancement of magnetic-gold core–shell nanoparticles’ by Asahi Tomitaka et al., Nanoscale, 2019, 11, 6489–6496, DOI: 10.1039/C9NR00242A.
Preparation of novel morning glory structure γ-MnO2/carbon nanofiber composite materials with the electrospinning method and their high electrochemical performance
Authors: Lan Ziwei , Luo Lulin , Ye Jiaye , Luo Qingyue , Zhao Lei
Published: October 2020

The large specific surface area of morning glory, ultra-stable γ-MnO2/carbon nanofiber radial structure and shorter diffusion path for mass and charge transport could enhance the Na+/H+ ions intercalation capacity, so as to obtain a 2 V high working potential range.
The alkali degradation of LDPE-based radiation-grafted anion-exchange membranes studied using different ex situ methods
Authors: Meek Kelly M. , Reed Carly M. , Pivovar Bryan , Kreuer Klaus-Dieter , Varcoe John R. , Bance-Soualhi Rachida
Published: October 2020

Three different ex situ alkali degradation protocols were compared on single batches of LDPE-based radiation-grafted anion-exchange membranes (containing trimethylammonium, N-methylpiperidinium, and N-methylpyrrolidinium headgroups).
Assessing long-range contributions to the charge asymmetry of ion adsorption at the air–water interface
Authors: Cox Stephen J. , Thorpe Dayton G. , Shaffer Patrick R. , Geissler Phillip L.
Published: October 2020

Cations and anions have different affinities for the air-water interface. The intrinsic orientation of surface molecules suggests such an asymmetry, but the bias is dominated by solvent response that is spatially local and significantly nonlinear.
Graph-based machine learning interprets and predicts diagnostic isomer-selective ion–molecule reactions in tandem mass spectrometry
Authors: Fine Jonathan , Kuan-Yu Liu Judy , Beck Armen , Alzarieni Kawthar Z. , Ma Xin , Boulos Victoria M. , Kenttämaa Hilkka I. , Chopra Gaurav
Published: October 2020

We combine mass spectrometry with machine learning that is predictive and explainable using chemical reactivity flowcharts for diagnostic ion–molecule reactions.
Shaping non-noble metal nanocrystals via colloidal chemistry
Authors: Mantella Valeria , Castilla-Amorós Laia , Buonsanti Raffaella
Published: October 2020

This minireview describes the state-of-the-art of shape-controlled nanocrystals of third raw transition metals and discusses future directions to advance their synthetic development, which is important for many applications.
Efficient visible-light activation of molecular oxygen to produce hydrogen peroxide using P doped g-C3N4 hollow spheres
Authors: Dang Xueming , Yang Ruying , Wang Zhe , Wu Siyi , Zhao Huimin
Published: October 2020

P doped g-C3N4 with a hollow sphere architecture is fabricated and exhibits a high H2O2 production rate.
General strategy for tuning the Stokes shifts of near infrared cyanine dyes
Authors: Zhang Jun , Moemeni Mehdi , Yang Chenchen , Liang Fangchun , Peng Wei-Tao , Levine Benjamin G. , Lunt Richard R. , Borhan Babak
Published: October 2020

A series of amine substituted cyanines show spectral characteristics that are dependent on the structure of the substituted amine, with Stokes shifts that range from 24–180 nm. Computational analysis informs on the ground and excited state structures.
2.09 Å Resolution structure of E. coli HigBA toxin–antitoxin complex reveals an ordered DNA-binding domain and intrinsic dynamics in antitoxin
Authors: Jadhav Pankaj Vilas , Sinha Vikrant Kumar , Chugh Saurabh , Kotyada Chaithanya , Bachhav Digvijay , Singh Ramandeep , Rothweiler Ulli , Singh Mahavir
Published: October 2020

The toxin–antitoxin (TA) systems are small operon systems that are involved in important physiological processes in bacteria such as stress response and persister cell formation. Escherichia coli HigBA complex belongs to the type II TA systems and consists of a protein toxin called HigB and a protein antitoxin called HigA. The toxin HigB is a ribosome-dependent endoribonuclease that cleaves the translating mRNAs at the ribosome A site. The antitoxin HigA directly binds the toxin HigB, rendering the HigBA complex catalytically inactive. The existing biochemical and structural studies had revealed that the HigBA complex forms a heterotetrameric assembly via dimerization of HigA antitoxin. Here, we report a high-resolution crystal structure of E. coli HigBA complex that revealed a well-ordered DNA binding domain in HigA antitoxin. Using SEC-MALS and ITC methods, we have determined the stoichiometry of complex formation between HigBA and a 33 bp DNA and report that HigBA complex as well as HigA homodimer bind to the palindromic DNA sequence with nano molar affinity. Using E. coli growth assays, we have probed the roles of key, putative active site residues in HigB. Spectroscopic methods (CD and NMR) and molecular dynamics simulations study revealed intrinsic dynamic in antitoxin in HigBA complex, which may explain the large conformational changes in HigA homodimer in free and HigBA complexes observed previously. We also report a truncated, heterodimeric form of HigBA complex that revealed possible cleavage sites in HigBA complex, which can have implications for its cellular functions.
The relationship between intestinal goblet cells and the immune response
Authors: Zhang Mingming , Wu Chenchen
Published: October 2020

Goblet cells (GCs) are single-cell glands that produce and secrete mucin. Mucin forms a mucus layer, which can separate the materials in cavities from the intestinal epithelium and prevent the invasion of pathogenic microorganisms in various ways. GCs can also participate in the immune response through nonspecific endocytosis and goblet cell-associated antigen passages (GAPs). GCs endocytose soluble substances from the lumen and transmit antigens to the underlying antigen-presenting cells (APCs). A variety of immuno-regulatory factors can promote the differentiation, maturation of GCs, and the secretion of mucin. The mucin secreted by GCs forms a mucus layer, which plays an important role in resisting the invasion of foreign bacteria and intestinal inherent microorganisms, regulating the immune performance of the body. Therefore, the present study mainly reviews the barrier function of the mucus layer, the mucus secreted by goblet cells, the protective effect against pathogenic bacteria, the delivery of luminal substances through GAPs and the relationship between GCs and the immune response.
Condensin complexes: understanding loop extrusion one conformational change at a time
Authors: Cutts Erin E. , Vannini Alessandro
Published: October 2020

Condensin and cohesin, both members of the structural maintenance of chromosome (SMC) family, contribute to the regulation and structure of chromatin. Recent work has shown both condensin and cohesin extrude DNA loops and most likely work via a conserved mechanism. This review focuses on condensin complexes, highlighting recent in vitro work characterising DNA loop formation and protein structure. We discuss similarities between condensin and cohesin complexes to derive a possible mechanistic model, as well as discuss differences that exist between the different condensin isoforms found in higher eukaryotes.
Studying the surfaces of bacteria using neutron scattering: finding new openings for antibiotics
Authors: Paracini Nicolò , Clifton Luke A. , Lakey Jeremy H.
Published: October 2020

The use of neutrons as a scattering probe to investigate biological membranes has steadily grown in the past three decades, shedding light on the structure and behaviour of this ubiquitous and fundamental biological barrier. Meanwhile, the rise of antibiotic resistance has catalysed a renewed interest in understanding the mechanisms underlying the dynamics of antibiotics interaction with the bacterial cell envelope. It is widely recognised that the key reason behind the remarkable success of Gram-negative pathogens in developing antibiotic resistance lies in the effectiveness of their outer membrane (OM) in defending the cell from antibacterial compounds. Critical to its function, the highly asymmetric lipid distribution between the inner and outer bilayer leaflets of the OM, adds an extra level of complexity to the study of this crucial defence barrier. Here we review the opportunities offered by neutron scattering techniques, in particular reflectometry, to provide structural information on the interactions of antimicrobials with in vitro models of the OM. The differential sensitivity of neutrons towards hydrogen and deuterium makes them a unique probe to study the structure and behaviour of asymmetric membranes. Molecular-level understanding of the interactions between antimicrobials and the Gram-negative OM provides valuable insights that can aid drug development and broaden our knowledge of this critically important biological barrier.
Prematurity negatively affects regenerative properties of human amniotic epithelial cells in the context of lung repair
Authors: Zhu Dandan , Kusuma Gina D. , Schwab Renate , Chan Siow Teng , Tan Jean , Saad Mohamed I. , Leeman Kristen T. , Kim Carla , Wallace Euan M. , Lim Rebecca
Published: October 2020

There is a growing appreciation of the role of lung stem/progenitor cells in the development and perpetuation of chronic lung disease including idiopathic pulmonary fibrosis. Human amniotic epithelial cells (hAECs) were previously shown to improve lung architecture in bleomycin-induced lung injury, with the further suggestion that hAECs obtained from term pregnancies possessed superior anti-fibrotic properties compared with their preterm counterparts. In the present study, we aimed to elucidate the differential effects of hAECs from term and preterm pregnancies on lung stem/progenitor cells involved in the repair. Here we showed that term hAECs were better able to activate bronchioalveolar stem cells (BASCs) and type 2 alveolar epithelial cells (AT2s) compared with preterm hAECs following bleomycin challenge. Further, we observed that term hAECs restored TGIF1 and TGFβ2 expression levels, while increasing c-MYC expression despite an absence of significant changes to Wnt/β-catenin signaling. In vitro, term hAECs increased the average size and numbers of BASC and AT2 colonies. The gene expression levels of Wnt ligands were higher in term hAECs, and the expression levels of BMP4, CCND1 and CDC42 were only increased in the BASC and AT2 organoids co-cultured with hAECs from term pregnancies but not preterm pregnancies. In conclusion, term hAECs were more efficient at activating the BASC niche compared with preterm hAECs. The impact of gestational age and/or complications leading to preterm delivery should be considered when applying hAECs and other gestational tissue-derived stem and stem-like cells therapeutically.
MUSE observations towards the lensing cluster A2744: Intersection between the LBG and LAE populations at z ∼ 3–7
Authors: de La Vieuville G. , Pelló R. , Richard J. , Mahler G. , Lévêque L. , Bauer F. E. , Lagattuta D. J. , Blaizot J. , Contini T. , Guaita L. , Kusakabe H. , Laporte N. , Martinez J. , Maseda M. V. , Schaerer D. , Schmidt K. B. , Verhamme A.
Published: October 2020

We present a study of the intersection between the populations of star forming galaxies selected as either Lyman break galaxies (LBGs) or Lyman-alpha emitters (LAEs) in the redshift range 2.9 − 6.7 and within the same volume of universe sampled by the Multi-Unit Spectroscopic Explorer (MUSE) behind the Hubble Frontier Fields lensing cluster A2744. We define three samples of star-forming galaxies: LBG galaxies with an LAE counterpart (92 galaxies), LBG galaxies without an LAE counterpart (408 galaxies), and LAE galaxies without an LBG counterpart (46 galaxies). All these galaxies are intrinsically faint because of the lensing nature of the sample (M1500 ≥ −20.5). The fraction of LAEs among all selected star-forming galaxies increases with redshift up to z ∼ 6 and decreases for higher redshifts, in agreement with previous findings. The evolution of LAE/LBG populations with UV magnitude and Lyα luminosity shows that the LAE selection is able to identify intrinsically UV faint galaxies with M1500 ≥ −15 that are typically missed in the deepest lensing photometric surveys. The LBG population seems to fairly represent the total population of star-forming galaxies down to M1500 ∼ −15. Galaxies with M1500 < −17 tend to have SFRLyα < SFRuv, whereas the opposite trend is observed within our sample for faint galaxies with M1500 > −17, including galaxies only detected by their Lyα emission, with a large scatter. These trends, previously observed in other samples of star-forming galaxies at high-z, are seen here for very faint M1500 ∼ −15 galaxies; that is, much fainter than in previous studies. The present results show no clear evidence for an intrinsic difference between the properties of the two populations selected as LBG and/or LAE. The observed trends could be explained by a combination of several phenomena, like the existence of different star-formation regimes, the dust content, the relative distribution and morphology of dust and stars, or the stellar populations.
Reconciling escape fractions and observed line emission in Lyman-continuum-leaking galaxies
Authors: Ramambason L. , Schaerer D. , Stasińska G. , Izotov Y. I. , Guseva N. G. , Vílchez J. M. , Amorín R. , Morisset C.
Published: October 2020

Context. Finding and elucidating the properties of Lyman-continuum(LyC)-emitting galaxies is an important step in improving our understanding of cosmic reionization.

Aims. Although the z ∼ 0.3 − 0.4 LyC emitters found recently show strong optical emission lines, no consistent quantitative photoionization model taking into account the escape of ionizing photons and inhomogenous interstellar medium (ISM) geometry of these galaxies has yet been constructed. Furthermore, it is unclear to what extent these emission lines can be used to distinguish LyC emitters.

Methods. To address these questions we construct one- and two-zone photoionization models accounting for the observed LyC escape, which we compare to the observed emission line measurements. The main diagnostics used include lines of [O III], [O II], and [O I] plus sulfur lines ([S II], [S III]) and a nitrogen line ([N II]), which probe regions of different ionization in the ISM.

Results. We find that single (one-zone) density-bounded photoionization models cannot reproduce the emission lines of the LyC leakers, as pointed out by earlier studies, because they systematically underpredict the lines of species of low ionization potential, such as [O I] and [S II]. Introducing a two-zone model, with differing ionization parameter and a variable covering fraction and where one of the zones is density-bounded, we show that the observed emission line ratios of the LyC emitters are well reproduced. Furthermore, our model yields LyC escape fractions, which are in fair agreement with the observations and independent measurements. The [O I] λ6300 excess, which is observed in some LyC leakers, can be naturally explained in this model, for example by emission from low-ionization and low-filling-factor gas. LyC emitters with a high escape fraction (fesc ≳ 38%) are deficient both in [O I] λ6300 and in [S II] λλ6716,6731. We also confirm that a [S II] λλ6716,6731 deficiency can be used to select LyC emitter candidates, as suggested earlier. Finally, we find indications for a possible dichotomy in terms of escape mechanisms for LyC photons between galaxies with relatively low (fesc ≲ 10%) and higher escape fractions.

Conclusions. We conclude that two-zone photoionization models are sufficient and required to explain the observed emission line properties of z ∼ 0.3 − 0.4 LyC emitters. This is in agreement with UV absorption line studies, which also show the co-existence of regions with high hydrogen column density (i.e., no escape of ionizing photons) and density-bounded or very low column density regions responsible for the observed escape of LyC radiation. These simple but consistent models provide a first step towards the use of optical emission lines and their ratios as quantitative diagnostics of LyC escape from galaxies.
Assessment of RC elements strengthened with NSM FRP rods by experimental tests
Authors: Capozucca Roberto , Magagnini Erica
Published: October 2020

Near surface mounted (NSM) technique of strengthening with FRP rods inserted in grooves on the concrete cover of damaged RC beams has been improved in recent years. The aim of this paper is the examination of the static and dynamic behaviour of undamaged and damaged reinforced concrete (RC) beams with free-free ends. RC beams strengthened with NSM Glass and Carbon fiber reinforced polymer (G-CFRP) rods have been experimentally analysed. The damage of the RC beam model was obtained by the cracking of concrete under bending tests. The detection of damage and monitoring of RC beams with and without strengthening were carried out by vibration tests assuming free-free ends at different degree of damage. Envelope diagrams of Frequency Response Functions (FRFs) obtained by the dynamic experimental tests are shown and the changes of natural frequency values are correlated to the damage degree of beam elements. Experimental results are discussed with particular emphasis on the aspect of the loss of bond.
Mechanical properties and carbon footprint of 3D-printable cement mortars with biochar additions
Authors: Falliano Devid , De Domenico Dario , Quattrocchi Salvatore , Cosenza Paolo , Ricciardi Giuseppe , Restuccia Luciana , Ferro Giuseppe Andrea
Published: October 2020

This contribution focuses on the design and the characterization of innovative mix designs of high consistency mortars with biochar additions in different percentage with respect to the cement weight. Biochar is a by-product material that gives the cementitious mix a sustainable connotation from an environmental point of view. The mix designs presented here are characterized by a good dimensional stability in the fresh state, peculiarity that gives them the possibility to be extruded and so, to be used in automated construction processes. In addition to the mechanical properties (flexural and compressive strength), the assessment of the CO2 emission of representative mixes is presented. Different biochar content and maximum diameter of the aggregate are studied, obtaining interesting indications on these parameters to optimize mechanical properties. Finally, on the basis of the CO2 emission assessment, certain venues for future research work to minimize CO2 emissions are reported.
Effect of shear span-to-depth ratio on posttensioned concrete crane beams shear capacity
Authors: Derkowski Wit , Walczak Rafał
Published: October 2020

The shear span-to-depth ratio has the most significant influence on the shear capacity of beams and determines their failure mode. The subject of the current project is the shear capacity of precast posttensioned concrete crane beams disassembled after more than fifty years of being used in an industrial plant. The paper gives the theoretical basis for the shear capacity of such elements as well as standard design models. The conducted tests showed that despite the low shear reinforcement ratio, the elements do not fail in a brittle mode but show a clear indication of prospective destruction. It was also confirmed that in the case of poorly shear-reinforced PC elements, a clear arch action can be distinguished with a low shear span-to-depth ratio, whereas in the case of a higher ratio there is a classical beam action.
Innovative approaches for strengthening existing concrete structures
Authors: Randl Norbert
Published: October 2020

The demand of effective and low-invasive methods for strengthening existing concrete structures is continuously increasing due to the ageing infrastructure. High performance materials can beneficially be applied to provide sustainable and robust strengthening solutions. The present article presents some exemplarily selected methods and innovative approaches for subsequent strengthening of existing RC structures. Main results of experimental investigations are summarized and future research topics identified.