bluuebunny/crossref_metadata_2025 huggingface dataset:
Forever Young: Structural Stability of Telomeric Guanine Quadruplexes in the Presence of Oxidative DNA Lesions**
Authors: Miclot Tom , Corbier Camille , Terenzi Alessio , Hognon Cécilia , Grandemange Stéphanie , Barone Giampaolo , Monari Antonio
Published: April 2021

Human telomeric DNA, in G‐quadruplex (G4) conformation, is characterized by a remarkable structural stability that confers it the capacity to resist to oxidative stress producing one or even clustered 8‐oxoguanine (8oxoG) lesions. We present a combined experimental/computational investigation, by using circular dichroism in aqueous solutions, cellular immunofluorescence assays and molecular dynamics simulations, that identifies the crucial role of the stability of G4s to oxidative lesions, related also to their biological role as inhibitors of telomerase, an enzyme overexpressed in most cancers associated to oxidative stress.
Single Mn Atom Anchored on Nitrogen‐Doped Graphene as a Highly Efficient Electrocatalyst for Oxygen Reduction Reaction
Authors: Li Lei , Li Yameng , Huang Rao , Cao Xinrui , Wen Yuhua
Published: April 2021

Single Mn atom on nitrogen‐doped graphene (MnN4‐G) has exhibited good structural stability and high activity for the adsorption and dissociation of an O2 molecule, becoming a promising single‐atom catalyst (SAC) candidate for oxygen reduction reaction (ORR). However, the catalytic activity of MnN4‐G for the ORR and the optimal reaction pathway remain obscure. In this work, density‐functional theory calculations were employed to comprehensively investigate all the possible pathways and intermediate reactions of the ORR on MnN4‐G. The feasible active sites and the most stable adsorption configurations of the intermediates and transition states during the ORR were identified. Screened from all the possibilities, three optimal four‐electron O2 hydrogenation pathways with an ultralow energy barrier of 0.13 eV were discovered that are energetically more favorable than direct O2 dissociation pathways. Analysis of the free energy diagram further verified the thermodynamical feasibility of the three pathways. Thus, MnN4‐G possesses superior ORR activity. This study provides a fundamental understanding of the design of highly efficient SACs for the ORR.
Rapidly Adaptive All‐covalent Nanoparticle Surface Engineering
Authors: Diez‐Castellnou Marta , Suo Rongtian , Marro Nicolas , Matthew Saphia A. L. , Kay Euan R.
Published: April 2021

Emerging nanotechnologies demand the manipulation of nanoscale components with the same predictability and programmability as is taken for granted in molecular synthetic methodologies. Yet installing appropriately reactive chemical functionality on nanomaterial surfaces has previously entailed compromises in terms of reactivity scope, functionalization density, or both. Here, we introduce an idealized dynamic covalent nanoparticle building block for divergent and adaptive post‐synthesis modification of colloidal nanomaterials. Acetal‐protected monolayer‐stabilized gold nanoparticles are prepared via operationally simple protocols and are stable to long‐term storage. Tunable surface densities of reactive aldehyde functionalities are revealed on‐demand, leading to a wide range of adaptive surface engineering options from one nanoscale synthon. Analytically tractable with molecular precision, interfacial reaction kinetics and dynamic surface constitutions can be probed in situ at the ensemble level. High functionalization densities combined with rapid equilibration kinetics enable environmentally adaptive surface constitutions and rapid nanoparticle property switching in response to simple chemical effectors.
Solution‐Processed Silver Nanowire as Flexible Transparent Electrodes in Organic Solar Cells
Authors: Yang Yi , Xu Bowei , Hou Jianhui
Published: April 2021

Organic solar cells (OSCs) have attracted much attention due to their advantages in fabricating flexible and semi‐transparent devices. Especially, the light weight, flexibility and spectral adjustability make OSCs superior to silicon, perovskite and other thin film based solar cells in applications of integrated photovoltaic devices and wearable electronics. In flexible and semi‐transparent OSCs, transparent conducting electrodes (TCEs) play a key role in obtaining high performances. Among various TCEs, silver nanowire (AgNW) has become a promising candidate due to its low sheet resistance, high optical transparency, excellent mechanical flexibility and solution processability. In this article, we review the recent advances in AgNW‐based TCEs and their applications in the field of OSCs. Firstly, we introduce the general properties of AgNW, including optoelectronic and mechanical characteristics. Secondly, the preparation methods of AgNW are discussed, along with some approaches on the optimization of AgNW to overcome the shortcomings of TCEs. Thirdly, we discuss the applications of AgNW as TCEs in fabricating flexible and semi‐transparent OSCs, including the use of AgNW as bottom and top electrodes. Finally, we point out the challenges in AgNW‐based TCEs and suggest several guidelines for preparing AgNW so as to meet the demands for the practical use of OSCs.
First Principle Studies to Tailor Graphene Through Synergistic Effect as a Highly Efficient Electrocatalyst for Oxygen Evolution Reaction
Authors: Riyaz Mohd , Gupta Shuchi , Goel Neetu
Published: April 2021

The Oxygen Evolution Reaction (OER) is one of the major roadblocks for electrocatalytic oxidation of water (water splitting) and for designing efficient metal‐air batteries. Herein, we present a comprehensive study to design graphene based efficient electrocatalyst, modified by doping with main group elements Al, Si, P, S and co‐doping with B and N, for OER using DFT computations. Four elementary steps in the OER reaction have been traced, free energy change for each elementary step was calculated considering thermodynamic corrections. Out of all the doped models, S doped graphene shows maximum efficiency that was further enhanced by adjusting the concentration of codopants B and N around the active dopant site. Our results show that synergy between codopants B and N and dopant S atom leads to high electrocatalytic efficiency of modified graphene towards OER and brings down the overpotential to as low as 0.44 V.
How Do Defects in Carbon Nanostructures Regulate the Photoinduced Electron Transfer Processes? The Case of Phenine Nanotubes
Authors: Stasyuk Olga A. , Stasyuk Anton J. , Solà Miquel , Voityuk Alexander A.
Published: April 2021

Photoinduced electron transfer is studied in a series of inclusion complexes of structurally modified phenine nanotubes (pNT) withC70using the TD‐DFT method. Analysis of electronic properties of the complexes shows that the electron transfer is infeasible inpNT_4d⊃C70built on the tetrameric array of [6]cyclo‐meta‐phenylene ([6]CMP) units. However, replacing one or more [6]CMP units with a coronene moiety enables electron transfer frompNTtoC70. The generation of the charge separated states from the lowest locally excited states occurs on a sub‐nanosecond time scale. Depending on the number of the [6]CMP units, the charge recombination rate varies from 1.8 ⋅ 107to 3.1 ⋅ 102 s−1, i. e., five orders of magnitude.
Formation of Titanium Nitride, Titanium Carbide, and Silicon Carbide Surfaces by High Power Femtosecond Laser Treatment
Authors: Fedorov Rostislav , Lederle Felix , Li Mingji , Olszok Vinzent , Wöbbeking Karl , Schade Wolfgang , Hübner Eike G.
Published: April 2021

Coatings based on titanium nitrides, titanium carbides and silicon carbides can optimize the surface properties of titanium or silicon for various applications ranging from biocompatibility to chemical stability and durability. Here, we investigated a high power (100 W) high pulse repetition rate femtosecond laser process (λ=1030 nm, τ=750 fs, f=1 MHz) for the treatment of titanium and silicon in atmospheres of argon, nitrogen, methane, ethene and acetylene. In a nitrogen atmosphere, a homogeneous coating of TiON is formed on titanium. In an ethene/argon atmosphere coatings of TiOC and SiC are formed on Ti and Si, respectively. The process allows a fast surface transformation with a process rate of 0.33 cm2 s−1 and a high spatial resolution below 0.5 mm with a minimal heat affected zone at the same time. In contrast to low repetition rate femtosecond laser processed samples, the surfaces are more robust against mechanical impact. At the same time, the surfaces reveal a distinct microstructure in comparison to coatings obtained by vapor deposition techniques.
Recyclable, Bifunctional Metallaphotocatalysts for C−S Cross‐Coupling Reactions
Authors: Reischauer Susanne , Pieber Bartholomäus
Published: April 2021

Metallaphotocatalytic cross‐coupling reactions are typically carried out by combining homogeneous or heterogeneous photocatalysts with a soluble nickel complex. Previous attempts to realize recyclable catalytic systems use immobilized iridium complexes to harvest light. We present bifunctional materials based on semiconductors for metallaphotocatalytic C−S cross‐coupling reactions that can be reused without losing their catalytic activity. Key to the success is the permanent immobilization of a nickel complex on the surface of a heterogeneous semiconductor through phosphonic acid anchors. The optimized catalyst harvests a broad range of the visible light spectrum and requires a nickel loading of only ∼0.1 mol %.
Climate and multiple dimensions of plant diversity regulate ecosystem carbon exchange along an elevational gradient
Authors: Prager Case M. , Jing Xin , Henning Jeremiah A. , Read Quentin D. , Meidl Peter , Lavorel Sandra , Sanders Nathan J. , Sundqvist Maja , Wardle David A. , Classen Aimee T.
Published: April 2021

The impacts of warming on communities and ecosystems are predicted to be significant in mountain ecosystems because physiological processes, including rates of carbon (C) cycling, are often more temperature‐sensitive in colder environments. Plant biodiversity can also influence C exchange, yet few studies integrate how biotic and abiotic factors may directly or interactively impact ecosystem C flux. Here, we examine the link between simultaneous changes in multiple dimensions of plant diversity and peak growing season ecosystem C uptake across a climatic gradient in the Rocky Mountains, Colorado, USA. We found that taxonomic diversity (species richness), functional diversity (functional evenness), and phylogenetic diversity (mean pairwise distance) were significantly and positively related to peak growing season ecosystem C uptake (i.e., net ecosystem exchange) when considered independently. However, when abiotic and biotic factors were integrated in a structural equation model, only plant phylogenetic diversity was significantly related to C uptake. In addition, we found that actual evapotranspiration (AET—a measure that integrates precipitation and temperature) affected ecosystem C exchange indirectly via its impact on the three dimensions of plant diversity that we examined. These findings highlight complex relationships among key measures of biodiversity and ecosystem C uptake in a rapidly warming ecosystem, and the possible mechanisms that underlie relationships between biodiversity and ecosystem functioning. They also point to the need for integrating multiple dimensions of biodiversity into studies of community and ecosystem ecology.
Use of Isopropyl Alcohol as a Reductant for Catalytic Dehydoxylative Dimerization of Benzylic Alcohols Utilizing Ti−O Bond Photohomolysis
Authors: Sumiyama Keiichi , Toriumi Naoyuki , Iwasawa Nobuharu
Published: April 2021

Photohomolysis of Ti−O bonds is utilized in photocatalytic generation of titanium(III) species for dehydroxylative dimerization of benzylic alcohols under UV‐light irradiation by using isopropyl alcohol (IPA) as a stoichiometric reductant. In this reaction, IPA works not as a single‐electron donor as in the photo‐redox catalyzed reactions but as an H‐atom‐donor. The reaction also proceeds under visible‐light irradiation in the presence of thioglycolic acid as a ligand.
Copper Catalyzed Protosilylation/Protoborylation of gem‐Difluoroallenes
Authors: Shan Cui‐Cui , Dai Kai‐Yang , Zhao Meng , Xu Yun‐He
Published: April 2021

We have developed a protocol for protoborylation and protosilylation of gem‐difluoroallenes to afford gem‐difluoroallyl‐boronates and gem‐difluoroallylsilanes. It is different from non‐fluorine allenes in which nucleophiles are added to γ‐position of gem‐difluoroallenes to afford β,γ‐addition products. Not only monosubstituted gem‐difluoroallenes but also disubstituted gem‐difluoroallenes could react well with silaboronate (PhMe2Si−Bpin) and bis(pinacolato)diboron (B2pin2). The protocol is simple and efficient to construct compounds which contain tertiary/secondary gem‐difluoroallylboronates and gem‐difluoroallylsilanes. Moreover, diverse organofluorine compounds can be converted from these organoboronates and silanes.
A Highly Sensitive and Selective Label‐free Electrochemical Biosensor with a Wide Range of Applications for Bisphenol A Detection
Authors: Yang Yingying , Liu Siyao , Shi Penghui , Zhao Guohua
Published: April 2021

A label‐free DNA‐based electrochemical biosensor owning high sensitivity and selectivity has been established for detecting bisphenol A in a wide range of applications. Coupling the high electrochemical performance of graphene oxide‐thionine‐Au nanomaterial with the specific binding capacity of the aptamers to BPA, the monitoring of trace amount of BPA was realized, the detection limit was 3.3 pg ⋅ mL−1 with strong anti‐interference. Besides, using molecular docking, it was found that BPA binds to the bases DC‐49, DC‐51, DG‐52, DG‐53 and DA‐63 on the aptamer via hydrogen bonding and π‐π stacking interactions. Finally, the biosensor had been successfully applied in different real samples.
Oral irritation in patients with chemosensory dysfunction
Authors: Han Pengfei , Seo Han‐Seok , Klockow Marie , Yan Xiaoguang , Hähner Antje , Hummel Thomas
Published: April 2021

Introduction

Evidence accumulates to support the interaction among gustatory, olfactory and trigeminal sensations. While olfactory dysfunction is associated with impaired taste or intranasal trigeminal perception, less is known about the perception of oral irritative intensity among patients with olfactory or gustatory dysfunctions.

Method

148 patients with olfactory and/or gustatory dysfunctions received oral administration of chili powder samples with varied irritation levels, and rated the oral irritation intensity on an 11‐point scale. Gustatory sensitivity was assessed using the ‘Taste Strips’ test among a subset of the patients (N = 25). Other variables including the aetiology of disease and a frequency of spicy food consumption were also recorded for exploratory analyses.

Results

Participants with anosmia rated oral irritations of chili powder significantly less than participants with normosmia. In the subsample, a positive correlation was observed between the individual scores of the ‘Taste Strips’ test and ratings of oral irritation intensity at the highest level of chili powder test. There were no effects of age, aetiology, subjective ratings of sensitivity to spicy food or frequency of spicy food consumption with respect to oral irritation intensity of chili powder samples.

Conclusion

The current results showed reduced oral irritation intensity among patients with severe olfactory loss. Impaired oral irritative perception among these participants may be related to disturbed central nervous interactions between the various sensory systems involved in flavour perception.
MHD instability of the pressure‐driven plane laminar flow in the presence of the uniform coplanar magnetic field: Linear stability analysis
Authors: Basavaraj M. S. , Aruna A. S. , Kumar Vijaya , Shobha T.
Published: April 2021

The influence of the uniform longitudinal magnetic field on the stability against small disturbances of an electrically conducting Newtonian fluid flow between two parallel horizontal plates is investigated. The sixth‐order system of disturbance equations is solved by the Chebyshev collocation method, and the critical Reynolds number , the critical wave number , and the critical wave speed are computed for a wide range of the magnetic Reynolds number and Alfven number A. Curves of wave number against Reynolds number for neutral stability are presented for different values of the parameters. The onset of instability is also discussed in detail using the growth rate curves for various parameters of the problem. It is observed that the effect of both conductivity of the fluid and the strength of the magnetic field is to decay the onset of instability. A comprehensive study is carried out at the critical state of the fluid using the graph of , , and with respect to for various values of A. The critical values at the onset of instability are also presented for both the Galerkin method and the Chebyshev collocation method.
Effect of material parameter on mixed convective fully developed micropolar fluid flow in a vertical channel
Authors: Kalyan Shreedevi , Sharan Ashwini , S Jyothi
Published: April 2021

In this study, the effect of material parameter on the mixed convective fully developed micropolar fluid flow in a vertical channel has been analyzed. By considering appropriate boundary and interface conditions, the coupled nonlinear equations are solved analytically. The analytical results are plotted for various important parameters. It is found that an increase in the material parameter enhances the microrotation velocity and decreases the fluid velocity, and the results are shown graphically.
Prediagnosis alcohol intake and metachronous cancer risk in cancer survivors: A prospective cohort study
Authors: Jayasekara Harindra , Hodge Allison M. , Haydon Andrew , Room Robin , Hopper John L. , English Dallas R. , Smith‐Warner Stephanie A. , Giles Graham G. , Milne Roger L. , MacInnis Robert J.
Published: April 2021

Alcohol consumption is a known cause of cancer, but its role in the etiology of second primary (metachronous) cancer is uncertain. Associations between alcohol intake up until study enrollment (prediagnosis) and risk of metachronous cancer were estimated using 9435 participants in the Melbourne Collaborative Cohort Study who were diagnosed with their first invasive cancer after enrollment (1990‐1994). Follow‐up was from date of first invasive cancer until diagnosis of metachronous cancer, death or censor date (February 2018), whichever came first. Alcohol intake for 10‐year periods from age 20 until decade encompassing baseline using recalled beverage‐specific frequency and quantity was used to calculate baseline and lifetime intakes, and group‐based intake trajectories. We estimated hazard ratios (HRs) and 95% confidence intervals (CIs), adjusted for potential confounders. After a mean follow‐up of 7 years, 1512 metachronous cancers were identified. A 10 g/d increment in prediagnosis lifetime alcohol intake (HR = 1.03, 95% CI = 1.00‐1.06; Pvalue = .02) and an intake of ≥60 g/d (HR = 1.32, 95% CI = 1.01‐1.73) were associated with increased metachronous cancer risk. We observed positive associations (per 10 g/d increment) for metachronous colorectal (HR = 1.07, 95% CI = 1.00‐1.14), upper aero‐digestive tract (UADT) (HR = 1.16, 95% CI = 1.00‐1.34) and kidney cancer (HR = 1.24, 95% CI = 1.10‐1.39). Although these findings were partly explained by effects of smoking, the association for kidney cancer remained unchanged when current smokers or obese individuals were excluded. Alcohol intake trajectories over the life course confirmed associations with metachronous cancer risk. Prediagnosis long‐term alcohol intake, and particularly heavy drinking, may increase the risk of metachronous cancer, particularly of the colorectum, UADT and kidney.
Irrigation frequencies and reference evapotranspiration replacement affecting annual bluegrass encroachment in perennial ryegrass in western Oregon
Authors: Cain Alyssa , Braithwaite Emily , McDonald Brian , Kowalewski Alec , Elmore Matthew
Published: April 2021

Annual bluegrass (Poa annua L.) encroachment may increase when turfgrass is maintained with excessive irrigation; however, with proper deficit irrigation, annual bluegrass germination and growth may be suppressed while desirable turfgrass is sustained. The goal of this project was to determine the optimal irrigation regime for suppressing annual bluegrass in perennial ryegrass (Lolium perenne L.) stands during the summer months. Two frequencies (once or four times a week) and rates (45% and 80% reference evapotranspiration [ETref] replacement) were used to assess the encroachment of annual bluegrass in perennial ryegrass maintained at 5 cm. Experimental design was a 2 × 2 factorial randomized complete block design with four replications. Preliminary findings suggest that irrigation applied once a week will reduce annual bluegrass compared to irrigation four times a week, while ETref replacement had no effect on annual bluegrass encroachment. Findings also suggest that frequent irrigation will increase turfgrass quality and soil moisture in the top 3.8 cm.
3D magnetic nanocomposite scaffolds enhanced the osteogenic capacities of rat bone mesenchymal stem cells in vitro and in a rat calvarial bone defect model by promoting cell adhesion
Authors: Han Liping , Guo Yu , Jia Lu , Zhang Qian , Sun Liuxu , Yang Zukun , Dai Yang , Lou Zhichao , Xia Yang
Published: April 2021

Magnetic scaffolds incorporated with iron oxide nanoparticles (IONPs) are biocompatible and present excellent osteogenic properties. However, the underlying mechanism is unclear. In this study, 3D‐printed poly(lactic‐co‐glycolic acid) scaffolds were coated with IONPs using layer‐by‐layer assembly (Fe‐scaffold) to prepare magnetic scaffolds. The effects of this modification on osteogenesis were investigated by comparison with untreated scaffolds (Uncoated‐scaffold). The results showed that the proliferation of rat bone mesenchymal stem cells (rBMSCs) on the Fe‐scaffold was enhanced compared with those on the Uncoated‐scaffold (p < 0.05). The alkaline phosphatase activity and expression levels of osteogenic‐related genes of cells on the Fe‐scaffold were higher than those on the Uncoated‐scaffold (p < 0.05). Fe‐scaffold was found to promote the cell adhesion compared with Uncoated‐scaffold, including increasing the adhered cell number, promoting cell spreading and upregulating the expression levels of adhesion‐related genes integrin α1 and β1 and their downstream signaling molecules FAK and ERK1/2 (p < 0.05). Moreover, the amount of new bone formed in rat calvarial defects at 8 weeks decreased in the order: Fe‐scaffold > Uncoated‐scaffold > Blank‐control (samples whose defects were left empty) (p < 0.05). Therefore, 3D magnetic nanocomposite scaffolds enhanced the osteogenic capacities of rBMSCs in vitro and in a rat calvarial bone defect model by promoting cell adhesion. The mechanisms were attributed to the alteration in its hydrophilicity, surface roughness, and chemical composition.
Monitoring mechanical stimulation for optimal tendon tissue engineering: A mechanical and biological multiscale study
Authors: Garcia Garcia Alejandro , Perot Jean‐baptiste , Beldjilali‐Labro Megane , Dermigny Quentin , Naudot Marie , Le Ricousse Sophie , Legallais Cecile , Bedoui Fahmi
Published: April 2021

To understand the effect of mechanical stimulation on cell response, bone marrow stromal cells were cultured on electrospun scaffolds under two distinct mechanical conditions (static and dynamic). Comparison between initial and final mechanical and biological properties of the cell‐constructs were conducted over 14 days for both culturing conditions. As a result, mechanically stimulated constructs, in contrast to their static counterparts, showed evident mechanical‐induced cell orientation, an effective aligned collagen and tenomodulin extracellular matrix. This orientation provides clues on the importance of mechanical stimulation to induce a tendon‐like differentiation. In addition, cell and collagen orientation lead to enhanced storage modulus observed under dynamic stimulation. Altogether mechanical stimulation lead to (a) cell and matrix orientation through the sense of the stretch and (b) a dominant elastic response in the cell‐constructs with a minor contribution of the viscosity in the global mechanical behavior. Such a correlation could help in further studies to better understand the effect of mechanical stimulation in tissue engineering.
Equilibrium between tri‐ and tetra‐coordinate chalcogenuranes is critical for cysteine protease inhibition
Authors: Dias‐da‐Silva Gabriela , L. O. R. Cunha Rodrigo , D. Coutinho‐Neto Mauricio
Published: April 2021

There have been significant advances in the biological use of hypervalent selenium and tellurium compounds as cysteine protease inhibitors. However, the full understanding of their reaction mechanisms for and cysteine proteases inhibition is still elusive. Kinetic studies suggest an irreversible inhibition mechanism, which was explained by forming a covalent bond between the enzyme sulfhydryl group and the chalcogen atom at its hypervalent state (+4). In this work, we performed a theoretical investigation using density functional theory to propose the active inhibitor form in an aqueous solution. To this end, we investigated chloride ligand exchange reactions by oxygen and sulfur nucleophiles on hypervalent selenium and tellurium compounds. All tetra‐ and tri‐coordinated chalcogen compounds and distinct protonation states of the nucleophiles were considered, totaling 34 unique species, 7 nucleophiles, and 155 free energies reactions. We discovered that chloride is easily replaced by a nonprotonated nucleophile (SH− or OH−) in R2SeCl2. We also found that tri‐coordinate species are more stable than their tetra‐coordinate counterparts, with selenoxide (R2SeO) protonation being strongly exergonic in acid pH. The thermodynamic and kinetic results suggest that the protonated selenoxide (R2SeOH+) is the most probable active chemical species in biological media. The computed energetic profiles paint a possible picture for selenuranes activity, with successive exergonic steps leading to a covalent inhibition of thiol‐dependent enzymes, like cysteine proteases. A second pathway has also been uncovered, with a direct reaction to chalcogenonium cation (R2SeCl+) as the inhibition step. Tellurium compounds showed similar trends but formed telluroxide in a pH‐independent fashion.
CDK14/β‐catenin/TCF4/miR‐26b positive feedback regulation modulating pancreatic cancer cell phenotypes in vitro and tumor growth in mice model in vivo
Authors: Sun Yunpeng , Wang Pengfei , Zhang Qiyu , Wu Huanhuan
Published: April 2021

Introduction

Chemotherapy and radiotherapy have been reported to be basically ineffective for pancreatic ductal adenocarcinoma patients; thus, gene therapy might provide a novel approach. CDK14, a new oncogenic member of the CDK family involved in the pancreatic cancer cell response to gemcitabine treatment, has been reported to be regulated by microRNAs. In the present study, we aimed to investigate whether miR‐26b regulated CDK14 expression to affect the phenotype of pancreatic cancer cells.

Methods

Overexpression or knockdown of CDK14 or miR‐26b was generated in pancreatic cancer cell lines and the function of CDK14 and miR‐26b on cell phenotype and the Wnt signaling pathway was determined using 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide, 5‐ethynyl‐2′‐deoxyuridine and transwell assays, as well as a xenograft model and western blotting. The predicted binding site between the 3′‐untranslated region of CDK14 and miR‐26b, miR‐26b promoter and TCF4 was verified by luciferase or chromatin immunoprecipitation assays.

Results

CDK14 overexpression inhibited p‐GSK3β, whereas it promoted p‐LRP6, the nuclear translocation of β‐catenin and the transactivation of TCF4 transcription factor, thus promoting pancreatic cancer cell aggressiveness. miR‐26b directly targeted CDK14 and inhibited CDK14 expression. In vitro and in vivo, miR‐26b overexpression inhibited, and CDK14 overexpression promoted, cancer cell aggressiveness; CDK14 overexpression partially attenuated the miR‐26b overexpression effects on cancer cells. The effects of miR‐26b overexpression on tumor growth and the Wnt/β‐catenin/TCF4 signaling were partially reversed by CDK14 overexpression. TCF4 inhibited the expression of miR‐26b by targeting its promoter region.

Conclusions

CDK14, β‐catenin, TCF4 and miR‐26b form a positive feedback regulation for modulating pancreatic cancer cell phenotypes in vitro and tumor growth in vivo.
Polymer–Protein Hybrid Network Involving Mucin: A Mineralized Biomimetic Template for Bone Tissue Engineering
Authors: Barik Debyashreeta , Bejugam Pruthvi Raj , Nayak Chumki , Mohanty Khirabdhi Tanaya , Singha Achintya , Declercq Heidi A. , Dash Mamoni
Published: April 2021

Biomimetic matrices offer a great advantage to understand several biological processes including regeneration. The study involves the development of a hybrid biomimetic scaffold and the uniqueness lies in the use of mucin, as a constituent protein. Through this study, the role of the protein in bone regeneration is deciphered through its development as a 3D model. As a first step towards understanding the protein, the interactions of mucin and collagen are determined by in silico studies considering that collagen is the most abundant protein in the bone microenvironment. Both proteins are reported to be involved in bone biology though the exact role of mucin is a topic of investigation. The in silico studies of collagen–mucin suggest to have a proper affinity toward each other, forming a strong basis for 3D scaffold development. The developed 3D scaffold is a double network system comprising of mucin and collagen and vinyl end functionalized polyethylene glycol. In situ deposition of mineral crystals has been performed enzymatically. Biological evaluation of these mineral deposited scaffolds is done in terms of their bone regeneration potential and a comparison of the two systems with and without mineral deposition is presented.
Topological Structure Design and Fabrication of Biocompatible PLA/TPU/ADM Mesh with Appropriate Elasticity for Hernia Repair
Authors: Hu Qingxi , Zhang Rennan , Zhang Haiguang , Yang Dongchao , Liu Suihong , Song Zhicheng , Gu Yan , Ramalingam Murugan
Published: April 2021

The meshes for hernia repair result in many problems that are related to complications including chronic pain and limited movement due to inadequate mechanical strength, non‐absorbability, or low elasticity. In this study, degradable polylactic acid (PLA), synthetic thermoplastic polyurethane (TPU), and acellular dermal matrix (ADM) powders are combined to prepare a novel PLA/TPU/ADM mesh with three different topological structures (square, circular, and diamond) by 3D printing. The physicochemical properties and structural characteristics of mesh are studied, the results show that the diamond structure mesh with the pore size of 3 mm has sufficient elasticity and tensile strength, which provides the efficient mechanical strength required for hernia repair (16 N cm−1) and the value more than polypropylene(PP) mesh. Besides, in vitro and in vivo experiments demonstrate human umbilical vein endothelial cells could successfully proliferate on the PLA/TPU/ADM mesh whose biocompatibility with the host is shown using a rat model of abdominal wall defect. In conclusion, the results of this study demonstrate that the PLA/TPU/ADM mesh may be considered a good choice for hernia repair as its potential to overcome the elastic and strength challenges associated with a highly flexible abdominal wall, as well as its good biocompatibility.
Highly efficient flame‐retardant and transparent epoxy resin
Authors: Liu Zhong , Yu Zhao , Qiaolin Tang , Kaixin Zhang , Weihao Deng , Lewen Zhang , Rong Wang , Jin Chen , Jingjing Deng , Wang Liao , Qiwei Wang , Mingjun Chen , Zhiguo Liu
Published: April 2021

In this study, a high effective phosphorus‐containing flame retardant (DOP‐DDM) was synthesized using phenylphosphonic dichloride, p‐hydroxybenzaldehyde, 9,10‐dihydro‐9‐oxa‐10‐phosphaphenan‐ threne‐10‐oxide (DOPO) and 4,4′‐diaminodiphenyl methane (DDM) as raw materials. The chemical structure of DOP‐DDM was confirmed by Fourier transform infrared spectroscopy (FT‐IR), 1H nuclear magnetic resonance (1H NMR) and 31P nuclear magnetic resonance (31P NMR). The epoxy resin (EP) material with 4.7 wt% DOP‐DDM (EP‐4.7) can reach V‐0 degree in UL 94 test and has LOI value as high as 33.5%. If neat EP (EP‐0) material is used as a control, even if the loading of DOP‐DDM in the flame‐retarded EP material reached 7.6 wt%, the transmittance can reach 96.8% of EP‐0. From cone combustion (CC) test, the peak of heat release rate (pHRR), total heat release (THR) and total smoke release (TSR) values of EP‐4.7 material were decreased in comparison to those of EP‐0. Compared with EP‐0 material, differential scanning calorimetry (DSC) and dynamic thermo mechanical (DMA) results showed that the glass transition temperature of EP‐4.7 material slightly increased, and the storage modulus (E′) and loss modulus (E′′) increased 65.7% and 47.3%, respectively. The morphology and graphitization degree of residual char after CC test were measured by SEM and Raman spectroscopy, respectively. Concurrently, the gas components of EP‐4.7 material were well analyzed by thermogravimetric analysis FTIR. All these results demonstrated that the DOP‐DDM played a role in gas‐phase and condensed‐phase.
An integrated strategy for the establishment of a protoberberine alkaloid profile: Exploration of the differences in composition between Tinosporae radix and Fibraurea caulis
Authors: Zhao Xueyan , Zhang Yan , Wang Quansheng , Huang Jiaxin , She Bo , Shi Qingxin , Xiang Xingliang , Su Chao , Zhang Lijun , Huang Rongzeng , Song Chengwu
Published: April 2021

Introduction

Accurate species and content identification of major active components in herbals are the guarantee of the safety and effectiveness for medical and commodity purposes.

Objectives

In this study, an integrated strategy used to establish the protoberberine alkaloid profile was applied to explore the differences in composition between the pieces of Tinosporae radix and Fibraurea caulis, both of which had morphological similarities.

Materials and methods

First, an in‐house library including possible protoberberine alkaloids based on different substituents was predicted by systematic literature survey. Meanwhile, diagnostic fragments of protoberberine alkaloids were investigated using the corresponding standards. Second, ultra‐performance liquid chromatography coupled with quadrupole time‐of‐flight mass spectrometry (UPLC‐QTOF‐MS/MS) was used to obtain multidimensional mass spectral data. Then, the identifications were confirmed by targeted filter of the acquired data based on the library.

Results

As a result, 10 protoberberine alkaloid molecules including 46 isomers were identified or characterised. The qualitative distribution and relative content of protoberberine alkaloids revealed the fundamental difference between Tinosporae radix and Fibraurea caulis. 25 alkaloids were present in both herbals, while five compounds were detected only in Tinosporae radix. Furthermore, the contents of four alkaloids in Tinosporae radix were significantly higher than those in its adulterant, Fibraurea caulis.

Conclusion

The five unique ingredients in Tinosporae radix can be used as a better indicator for distinguishing the pieces of Tinosporae radix and Fibraurea caulis. The protoberberine alkaloid profile established in this study can be applied to quality evaluation of the two herbals or other herbals containing major protoberberine alkaloids.
Management of noncardiovascular comorbidities in patients with heart failure with reduced ejection fraction
Authors: Gale Stormi E. , Mardis Andrew , Plazak Michael E. , Kukin Alina , Reed Brent N.
Published: April 2021

Patients with heart failure with reduced ejection fraction often have one or more noncardiovascular comorbidities. The presence of concomitant disease states is associated with worse outcomes, including increased risk of mortality, decreased quality of life, and increased healthcare resource utilization. Additionally, the presence of heart failure with reduced ejection fraction complicates the management of these comorbidities, including varying safety and efficacy of therapies compared to those without heart failure. This article will review the literature on the pharmacologic management of common noncardiovascular comorbidities—including chronic obstructive pulmonary disease, depression, diabetes mellitus, gout, chronic kidney disease, and iron deficiency—in patients with heart failure with reduced ejection fraction, as well as provide recommendations for appropriate treatment selection in this population.
Analysis of the degradation of single‐crystalline silicon modules after 21 years of operation
Authors: Piliougine Michel , Oukaja Amal , Sánchez‐Friera Paula , Petrone Giovanni , Sánchez‐Pacheco Francisco José , Spagnuolo Giovanni , Sidrach‐de‐Cardona Mariano
Published: April 2021

In this paper, the results of the analysis of the degradation of a set of single‐crystalline silicon modules after 21 years are presented. The comparison of the main electrical parameters and the series and of the shunt resistances measured in 1996 and 2017 is performed, so that the annual degradation rate is evaluated. In addition, a detailed analysis of the parameter uncertainties has been performed in order to determine its impact on the results. A visual inspection of the modules has also been carried out in order to show the correlation with the variation of the electrical performance. Finally, the temperature coefficients of the degraded modules have been estimated and compared with the nominal ones. The results shown in the paper reveal that the mean annual degradation rate in terms of power is close to 0.9%.
Effectiveness of online communication skills training for cancer and palliative care health professionals: A systematic review
Authors: Berg Melissa N. , Ngune Irene , Schofield Penelope , Grech Lisa , Juraskova Ilona , Strasser Michelle , Butt Zoe , Halkett Georgia K.B.
Published: April 2021

Objective

To determine the reported effect of online communication skills training (CST) on health professional (HP) communication skills and patient care outcomes in cancer and palliative care.

Methods

Primary research published in English between January 2003 and April 2019 was identified in bibliographic databases including Medline, Embase and Proquest (Prospero: CRD42018088681). An integrated mixed‐method approach included studies describing a CST intervention and its effect, for cancer or palliative care HPs, delivered online or blended with an online component. Included studies' outcomes were categorised then findings were stratified by an evaluation framework and synthesised in an effect direction plot. Risk of bias was assessed using Joanna Briggs Institute's tools.

Results

Nineteen included studies (five randomised controlled trials, 11 pre‐post, two post‐test and one qualitative study) evaluated a CST intervention (median duration = 3.75 h; range 0.66–96 h) involving 1116 HPs, 422 students and 732 patients. Most interventions taught communication skills for specific scenarios and approximately half were delivered solely online and did not involve role plays. Online CST improved HPs' self‐assessed communication skills (three studies, 215 participants), confidence (four studies, 533 participants), and objective knowledge (five studies, 753 participants). While few studies evaluated patient outcomes, CST may benefit observed communication skills in care settings (two studies, 595 participants).

Conclusions

Online CST benefits oncology HPs' subjectively‐reported communication skills and confidence, and objective knowledge. Translation to patient outcomes requires further investigation. The quality of research varied and few studies had a control group. We recommend improvements to study design, evaluation and implementation.
Subsurface phosphorus fluxes in a well‐drained forest soil are small and dominated by particulates
Authors: Henshaw Kalani , Bacon Allan , Cohen Matt , Vogel Jason , Judy Jonathan D.
Published: April 2021

Understanding ecosystem P cycling and the various pathways by which P is transported is crucial for sustainable nutrient management. Colloid‐facilitated transport of P is a poorly understood subsurface P flux pathway that may be particularly important in ecosystems with coarse‐textured soils and minimal surface runoff. This study examines subsurface transport of dissolved (as defined as P <3 kDa) and particulate P in well‐drained forest soils of two coniferous (pine) sites and one deciduous (oak) site. Total, dissolved and particulate (>0.45 μm and >3 kDa) groundwater P fluxes were quantified, as well as surface total P fluxes via litterfall and litter leachate. Our central hypothesis is that particulate and/or colloid‐associated subsurface P flux exceeds that of dissolved P flux as a result of dissolved P sorption to mobile and stationary Fe‐ and Al‐rich solid phases present in the soil. Results show that dissolved P flux (<3 kDa) was below detection in groundwater samples from all study sites, with the P within groundwater being dominated by particulates >0.45 μm. Overall, P fluxes from subsurface P pools (soils, groundwater) at all sites were one to three orders of magnitude lower than surface P inputs from litterfall and litter leachate, suggesting a highly efficient system for P conservation with minimal P losses below the root zone.
Exponential calibration for correlation coefficient with additive distortion measurement errors
Authors: Zhang Jun , Xu Zhuoer
Published: April 2021

This paper studies the estimation of correlation coefficient between unobserved variables of interest. These unobservable variables are distorted in an additive fashion by an observed confounding variable. We propose a new identifiability condition by using the exponential calibration to obtain calibrated variables and propose a direct‐plug‐in estimator for the correlation coefficient. We show that the direct‐plug‐in estimator is asymptotically efficient. Next, we suggest an asymptotic normal approximation and an empirical likelihood‐based statistic to construct the confidence intervals. Last, we propose several test statistics for testing whether the true correlation coefficient is zero or not. The asymptotic properties of the proposed test statistics are examined. We conduct Monte Carlo simulation experiments to examine the performance of the proposed estimators and test statistics. These methods are applied to analyze a temperature forecast data set for an illustration.
Stem Cells for Bronchopulmonary Dysplasia in Preterm Infants: A Randomized Controlled Phase II Trial
Authors: Ahn So Yoon , Chang Yun Sil , Lee Myung Hee , Sung Se In , Lee Byong Sop , Kim Ki Soo , Kim Ai-Rhan , Park Won Soon
Published: April 2021

We previously demonstrated the safety and feasibility of mesenchymal stem cell (MSC) transplantation for bronchopulmonary dysplasia (BPD) in preterm infants in a phase I clinical trial. We thus investigated the therapeutic efficacy of MSCs for BPD in premature infants. A phase II double-blind, randomized, placebo-controlled clinical trial was conducted on preterm infants at 23 to 28 gestational weeks (GW) receiving mechanical ventilator support with respiratory deterioration between postnatal days 5 and 14. Infants were stratified by 23 to 24 GW and 25 to 28 GW and randomly allocated (1:1) to receive stem cells (1 × 107 cells/kg, n = 33) or placebo (n = 33). Although the inflammatory cytokines in the tracheal aspirate fluid were significantly reduced with MSCs, the primary outcome of death or severe/moderate BPD in the control group (18/33, 55%) was not significantly improved with MSC transplantation (17/33, 52%). In the subgroup analysis, the secondary outcome of severe BPD was significantly improved from 53% (8/15) to 19% (3/16) with MSC transplantation in the 23 to 24 GW group but not in the 25 to 28 GW subgroup. In summary, although MSC transplantation might be safe and feasible, this small study was underpowered to detect its therapeutic efficacy in preterm infants at 23 to 28 GW. Accordingly, we are now conducting an additional larger and controlled phase II clinical trial focusing on infants at 23 to 24 GW (NCT03392467). ClinicalTrials.gov identifier: NCT01828957.
Phylogenomics of Brosimum (Moraceae) and allied genera, including a revised subgeneric system
Authors: Gardner Elliot M. , Audi Lauren , Zhang Qian , Sauquet Hervé , Monro Alexandre K. , Zerega Nyree J.C.
Published: April 2021

We present a phylogenomic study of Brosimum (Moraceae) and the allied genera Trymatococcus and Helianthostylis, with near‐complete taxon sampling. Distributed from Mexico and the Greater Antilles to the Amazon, this clade contains the underutilized crop ramón (bread nut) (Brosimum alicastrum) as well as other species valued for timber or medicinal uses. Target enrichment for 333 genes produced a well‐resolved phylogenetic tree and showed that Trymatococcus and Helianthostylis are nested within Brosimum. We present a revised subgeneric classification of Brosimum (19 spp.) based on phylogenetic and morphological considerations, including the reduction of Trymatococcus and Helianthostylis to subgenera. The monophyletic subgenera can be diagnosed based on stipule, pistillode, and cotyledon synapomorphies. Divergence date estimates suggest a Miocene origin for Brosimum, and ancestral area reconstruction indicated that all four subgenera originated and initially diversified in Amazonia before dispersing into other parts of South and Central America.
Congenital sensorineural deafness in Dogo Argentino dogs: Prevalence and phenotype associations
Authors: Strain George M.
Published: April 2021

Background

The Dogo Argentino dog breed is affected by hereditary congenital sensorineural deafness (CSD) associated with white pigmentation, but prevalence data and associations with phenotypes have not been reported.

Methods

In a retrospective study, animals were tested by the brainstem auditory evoked response, and phenotype data of sex, iris color, patch presence/absence and parent hearing status were collected. Chi‐square analyses were performed to identify associations between deafness and phenotype traits.

Results

BAER results and phenotype data were collected for 811 dogs. Hearing status was 74.23% bilaterally hearing, 20.35% unilaterally deaf and 5.43% bilaterally deaf or an overall prevalence of 25.77%. CSD was not associated with sex, but dogs without a patch had a significantly higher prevalence rate than patched dogs. Blue‐eyed dogs had higher prevalence rates than brown‐eyed dogs, but because of small sample size the χ2association was not considered valid. Insufficient numbers of dogs with a unilaterally deaf parent were present to assess the effects of parent hearing status.

Conclusion

Approximately one fourth of a US Dogo Argentino population was deaf in one or both ears, but dogs with a patch had a lower prevalence. Dogs with a blue eye were more likely to be deaf, but the association significance could not be reliably assessed.
Security in the Anthropocene
Authors: Trombetta Maria Julia
Published: April 2021

Environmental issues, ranging from climate change to scarcity of resources and diminishing biodiversity, present a set of challenges that suggest that we are now living in the Anthropocene. Many of these issues are expressed in security terms, with a growing emphasis on energy, environmental and water security. Analytical frameworks and existing institutions become dysfunctional, and problems cannot be dealt with in the old ways. Security needs to be rethought. This chapter provides an overview of the attempts and the challenges to reconceptualize security in the Anthropocene. How does a growing awareness of complex relations involving humans, non-humans and things question the very subject of security? Whose security is at stake, against what threats, by what means? It engages with the challenges that environmental problems pose to the discipline of international relations, its ontological and epistemological foundations and its categories of analysis and to security studies more specifically.