bluuebunny/crossref_metadata_2025 huggingface dataset:
Boosting potassium-ion batteries by few-layered composite anodes prepared via solution-triggered one-step shear exfoliation
Authors: Liu Yajie , Tai Zhixin , Zhang Jian , Pang Wei Kong , Zhang Qing , Feng Haifeng , Konstantinov Konstantin , Guo Zaiping , Liu Hua Kun
Published: September 2018

Earth-abundant potassium is a promising alternative to lithium in rechargeable batteries, but a pivotal limitation of potassium-ion batteries is their relatively low capacity and poor cycling stability. Here, a high-performance potassium-ion battery is achieved by employing few-layered antimony sulfide/carbon sheet composite anode fabricated via one-step high-shear exfoliation in ethanol/water solvent. Antimony sulfide with few-layered structure minimizes the volume expansion during potassiation and shortens the ion transport pathways, thus enhancing the rate capability; while carbon sheets in the composite provide electrical conductivity and maintain the electrode cycling stability by trapping the inevitable by-product, elemental sulfur. Meanwhile, the effect of the exfoliation solvent on the fabrication of two-dimensional antimony sulfide/carbon is also investigated. It is found that water facilitates the exfoliation by lower diffusion barrier along the [010] direction of antimony sulfide, while ethanol in the solvent acts as the carbon source for in situ carbonization.
Solubility-mediated sustained release enabling nitrate additive in carbonate electrolytes for stable lithium metal anode
Authors: Liu Yayuan , Lin Dingchang , Li Yuzhang , Chen Guangxu , Pei Allen , Nix Oliver , Li Yanbin , Cui Yi
Published: September 2018

The physiochemical properties of the solid-electrolyte interphase, primarily governed by electrolyte composition, have a profound impact on the electrochemical cycling of metallic lithium. Herein, we discover that the effect of nitrate anions on regulating lithium deposition previously known in ether-based electrolytes can be extended to carbonate-based systems, which dramatically alters the nuclei from dendritic to spherical, albeit extremely limited solubility. This is attributed to the preferential reduction of nitrate during solid-electrolyte interphase formation, and the mechanisms behind which are investigated based on the structure, ion-transport properties, and charge transfer kinetics of the modified interfacial environment. To overcome the solubility barrier, a solubility-mediated sustained-release methodology is introduced, in which nitrate nanoparticles are encapsulated in porous polymer gel and can be steadily dissolved during battery operation to maintain a high concentration at the electroplating front. As such, effective dendrite suppression and remarkably enhanced cycling stability are achieved in corrosive carbonate electrolytes.
Antagonistic chemical coupling in self-reconfigurable host–guest protocells
Authors: Martin Nicolas , Douliez Jean-Paul , Qiao Yan , Booth Richard , Li Mei , Mann Stephen
Published: September 2018

Fabrication of compartmentalised chemical systems with nested architectures and biomimetic properties has important implications for controlling the positional assembly of functional components, spatiotemporal regulation of enzyme cascades and modelling of proto-organelle behaviour in synthetic protocells. Here, we describe the spontaneous capture of glucose oxidase-containing proteinosomes in pH-sensitive fatty acid micelle coacervate droplets as a facile route to multi-compartmentalised host–guest protocells capable of antagonistic chemical and structural coupling. The nested system functions co-operatively at low-substrate turnover, while high levels of glucose give rise to pH-induced disassembly of the droplets, release of the incarcerated proteinosomes and self-reconfiguration into spatially organised enzymatically active vesicle-in-proteinosome protocells. Co-encapsulation of antagonistic enzymes within the proteinosomes produces a sequence of self-induced capture and host–guest reconfiguration. Taken together, our results highlight opportunities for the fabrication of self-reconfigurable host–guest protocells and provide a step towards the development of protocell populations exhibiting both synergistic and antagonistic modes of interaction.
Potential role of the HOXD8 transcription factor in cisplatin resistance and tumour metastasis in advanced epithelial ovarian cancer
Authors: Sun PengMing , Song YiYi , Liu DaBin , Liu GuiFen , Mao XiaoDan , Dong BinHua , Braicu Elena Ioana , Sehouli Jalid
Published: September 2018

Few studies have examined the potential transcription factor (TF) simultaneously associated with cisplatin resistance and metastasis in ovarian cancer. To assess a related mechanism, a 345-channel protein/DNA array and transcriptional activity ELISA were performed to compare the TF activities in the cisplatin-sensitive SKOV3 and cisplatin-resistant SKOV3-DDP cells and in HO-8910 and the homologous highly metastatic HO-8910PM cells. In SKOV3-DDP vs. SKOV3 cells, 43 TFs were up-regulated, while 31 were down-regulated. In HO-8910PM vs. HO-8910 cells, 13 TFs were up-regulated, while 18 were down-regulated. In these two models, 4 TFs (HOXD8(1), HOXD8(2), RB, RFX1/2/3) were simultaneously up-regulated, and 9 TFs (SRE, FKHR, Angiotensinogen ANG-IRE, Pax2, CD28RC/NF-IL2B, HLF, CPE, CBFB and c-Ets-1) were down-regulated. HOXD8 mRNA and protein expression levels measured by reverse transcription polymerase chain reaction and ELISA, respectively, were significantly higher in SKOV3-DDP and HO-8910PM than in their corresponding cell lines (both p < 0.05). In 52 cases of different ovarian disease, the patients with recurrent and cisplatin-resistant ovarian cancer had higher expression levels of HOXD8 than patients with primary malignant tumours (p = 0.018, p = 0.001) or benign tumours (p = 0.001, p < 0.001). Taken together, these results suggest that HOXD8 is potentially associated with both cisplatin resistance and metastasis in advanced ovarian cancer.
Novel analgesic ω-conotoxins from the vermivorous cone snail Conus moncuri provide new insights into the evolution of conopeptides
Authors: Sousa Silmara R. , McArthur Jeffrey R. , Brust Andreas , Bhola Rebecca F. , Rosengren K. Johan , Ragnarsson Lotten , Dutertre Sebastien , Alewood Paul F. , Christie Macdonald J. , Adams David J. , Vetter Irina , Lewis Richard J.
Published: September 2018

Cone snails are a diverse group of predatory marine invertebrates that deploy remarkably complex venoms to rapidly paralyse worm, mollusc or fish prey. ω-Conotoxins are neurotoxic peptides from cone snail venoms that inhibit Cav2.2 voltage-gated calcium channel, demonstrating potential for pain management via intrathecal (IT) administration. Here, we isolated and characterized two novel ω-conotoxins, MoVIA and MoVIB from Conus moncuri, the first to be identified in vermivorous (worm-hunting) cone snails. MoVIA and MoVIB potently inhibited human Cav2.2 in fluorimetric assays and rat Cav2.2 in patch clamp studies, and both potently displaced radiolabeled ω-conotoxin GVIA (125I-GVIA) from human SH-SY5Y cells and fish brain membranes (IC50 2–9 pM). Intriguingly, an arginine at position 13 in MoVIA and MoVIB replaced the functionally critical tyrosine found in piscivorous ω-conotoxins. To investigate its role, we synthesized MoVIB-[R13Y] and MVIIA-[Y13R]. Interestingly, MVIIA-[Y13R] completely lost Cav2.2 activity and MoVIB-[R13Y] had reduced activity, indicating that Arg at position 13 was preferred in these vermivorous ω-conotoxins whereas tyrosine 13 is preferred in piscivorous ω-conotoxins. MoVIB reversed pain behavior in a rat neuropathic pain model, confirming that vermivorous cone snails are a new source of analgesic ω-conotoxins. Given vermivorous cone snails are ancestral to piscivorous species, our findings support the repurposing of defensive venom peptides in the evolution of piscivorous Conidae.
Pancreatic Exocrine Tissue Architecture and Integrity are Maintained by E-cadherin During Postnatal Development
Authors: Serrill Jeffrey D. , Sander Maike , Shih Hung Ping
Published: September 2018

Cadherin-mediated cell-cell adhesion plays an important role in organ development and changes in cadherin expression are often linked to morphogenetic and pathogenic events. Cadherins interact with other intracellular components to form adherens junctions (AJs) and provide mechanical attachments between adjacent cells. E-cadherin (Cdh1) represents an integral component of these intercellular junctions. To elucidate the function of E-cadherin in the developing pancreas, we generated and studied pancreas-specific Cdh1-knockout (Cdh1ΔPan/ΔPan) mice. Cdh1ΔPan/ΔPan mice exhibit normal body size at birth, but fail to gain weight and become hypoglycemic soon afterward. We found that E-cadherin is not required for the establishment of apical-basal polarity or pancreatic exocrine cell identity at birth. However, four days after birth, the pancreata of Cdh1ΔPan/ΔPan mutants display progressive deterioration of exocrine architecture and dysregulation of Wnt and YAP signaling. At this time point, the acinar cells of Cdh1ΔPan/ΔPan mutants begin to exhibit ductal phenotypes, suggesting acinar-to-ductal metaplasia (ADM) in the E-cadherin-deficient pancreas. Our findings demonstrate that E-cadherin plays an integral role in the maintenance of exocrine architecture and regulation of homeostatic signaling. The present study provides insights into the involvement of cadherin-mediated cell-cell adhesion in pathogenic conditions such as pancreatitis or pancreatic cancer.
Accurate sound localization behavior in a gleaning bat, Antrozous pallidus
Authors: Brewton Dustin , Gutierrez Victoria , Razak Khaleel A
Published: September 2018

Acute auditory processing in bats is typically associated with echolocation. A subset of bats, called gleaners, listens to prey-generated noise to hunt surface-dwelling prey. Gleaners depend less on echolocation to hunt and, therefore, accurate localization of prey-generated noise is necessary for foraging success. Here we studied azimuth sound localization behavior in the pallid bat, a gleaning bat in which spatial encoding has been studied extensively. We tested pallid bats on a relatively difficult open loop task (single sound, duration ≤ 200 ms). The bats were trained to face the midline when stimulus was presented, and this was confirmed with video analysis. Bats localized broadband noise (5–30 kHz) from 1 out of 11 speakers spaced evenly across the horizontal plane of the frontal sound field. Approach to the correct speaker was rewarded. Pallid bats show accurate localization near the midline with mean errors between 3–6°. Remarkably, the accuracy does not decline significantly at peripheral locations with bats averaging  <~7° error upto 72° off midline. Manipulation of stimulus bandwidth shows that higher frequencies (20–30 kHz) are necessary for accurate localization. Comparative studies of gleaning bats will reveal convergent adaptations across auditory systems for non-echolocation-based behaviors in bats.
Author Correction: Novel inhibitors targeting Venezuelan equine encephalitis virus capsid protein identified using In Silico Structure-Based-Drug-Design
Authors: Shechter Sharon , Thomas David R. , Lundberg Lindsay , Pinkham Chelsea , Lin Shih-Chao , Wagstaff Kylie M. , Debono Aaron , Kehn-Hall Kylene , Jans David A.
Published: September 2018

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.
Parameter-Free Multiscale Simulation Realising Quantitative Prediction of Hole and Electron Mobilities in Organic Amorphous System with Multiple Frontier Orbitals
Authors: Kubo Shosei , Kaji Hironori
Published: September 2018

In amorphous organic semiconducting systems, hole and electron transfer has been considered to occur based on the overlap of highest occupied molecular orbitals (HOMOs) and that of lowest unoccupied molecular orbitals (LUMOs) between two adjacent molecules, respectively. Other molecular orbitals (MOs), HOMO−1, HOMO−2, … and LUMO+1, LUMO+2, …, have been neglected in charge transport calculations. However, these MOs could potentially contribute to charge transport. In this study, our multiscale simulations show that carriers are effectively transported not only via HOMOs or LUMOs but also via other MOs when the MOs are close in energy. Because these multiple MOs are active in charge transports, here we call them multiple frontier orbitals. Molecules with multiple frontier orbitals are found to possess high carrier mobility. The findings in this study provide guidelines to aid design of materials with excellent charge transport properties.
Warming in the Agulhas Region during the Global Surface Warming Acceleration and Slowdown
Authors: Han Lu , Yan Xiao-Hai
Published: September 2018

The Agulhas Region gains more heat during the global surface warming slowdown than acceleration period. Yet, mechanisms that cause excessive heat accumulation in this region remain largely unknown. We investigate the underlying physical processes and examine their influence on ocean heat changes in the last three decades. Heave is found to drive the increasing ocean heat content in the last three decades whereas elevated heat accumulation rate in slowdown compared than acceleration period is mainly attributed to spice. During the acceleration period, pure heaving of Subtropical Mode Water induced by wind stress change and pure warming caused by heat flux, leading to a strong heave component and relatively weak spice, drive the increases in ocean heat content. During the slowdown period, increasing salinity strengthens the spice, resulting in a higher heat accumulation rate compared to the acceleration period.
Neuronal network maturation differently affects secretory vesicles and mitochondria transport in axons
Authors: Moutaux Eve , Christaller Wilhelm , Scaramuzzino Chiara , Genoux Aurélie , Charlot Benoit , Cazorla Maxime , Saudou Frédéric
Published: September 2018

Studying intracellular dynamics in neurons is crucial to better understand how brain circuits communicate and adapt to environmental changes. In neurons, axonal secretory vesicles underlie various functions from growth during development to plasticity in the mature brain. Similarly, transport of mitochondria, the power plant of the cell, regulates both axonal development and synaptic homeostasis. However, because of their submicrometric size and rapid velocities, studying the kinetics of these organelles in projecting axons in vivo is technically challenging. In parallel, primary neuronal cultures are adapted to study axonal transport but they lack the physiological organization of neuronal networks, which in turn may bias observations. We previously developed a microfluidic platform to reconstruct a physiologically-relevant and functional corticostriatal network in vitro that is compatible with high-resolution videorecording of axonal trafficking. Here, using this system we report progressive changes in axonal transport kinetics of both dense core vesicles and mitochondria that correlate with network development and maturation. Interestingly, axonal flow of both types of organelles change in opposite directions, with rates increasing for vesicles and decreasing for mitochondria. Overall, our observations highlight the need for a better spatiotemporal control for the study of intracellular dynamics in order to avoid misinterpretations and improve reproducibility.
Scaling up electrically synchronized spin torque oscillator networks
Authors: Tsunegi Sumito , Taniguchi Tomohiro , Lebrun Romain , Yakushiji Kay , Cros Vincent , Grollier Julie , Fukushima Akio , Yuasa Shinji , Kubota Hitoshi
Published: September 2018

Synchronized nonlinear oscillators networks are at the core of numerous families of applications including phased array wave generators and neuromorphic pattern matching systems. In these devices, stable synchronization between large numbers of nanoscale oscillators is a key issue that remains to be demonstrated. Here, we show experimentally that synchronized spin-torque oscillator networks can be scaled up. By increasing the number of synchronized oscillators up to eight, we obtain that the emitted power and the quality factor increase linearly with the number of oscillators. Even more importantly, we demonstrate that the stability of synchronization in time exceeds 1.6 milliseconds corresponding to 105 periods of oscillation. Our study demonstrates that spin-torque oscillators are suitable for applications based on synchronized networks of oscillators.
Characterisation and functional predictions of canine long non-coding RNAs
Authors: Le Béguec Céline , Wucher Valentin , Lagoutte Lætitia , Cadieu Edouard , Botherel Nadine , Hédan Benoît , De Brito Clotilde , Guillory Anne-Sophie , André Catherine , Derrien Thomas , Hitte Christophe
Published: September 2018

Long non-coding RNAs (lncRNAs) are a family of heterogeneous RNAs that play major roles in multiple biological processes. We recently identified an extended repertoire of more than 10,000 lncRNAs of the domestic dog however, predicting their biological functionality remains challenging. In this study, we have characterised the expression profiles of 10,444 canine lncRNAs in 26 distinct tissue types, representing various anatomical systems. We showed that lncRNA expressions are mainly clustered by tissue type and we highlighted that 44% of canine lncRNAs are expressed in a tissue-specific manner. We further demonstrated that tissue-specificity correlates with specific families of canine transposable elements. In addition, we identified more than 900 conserved dog-human lncRNAs for which we show their overall reproducible expression patterns between dog and human through comparative transcriptomics. Finally, co-expression analyses of lncRNA and neighbouring protein-coding genes identified more than 3,400 canine lncRNAs, suggesting that functional roles of these lncRNAs act as regulatory elements. Altogether, this genomic and transcriptomic integrative study of lncRNAs constitutes a major resource to investigate genotype to phenotype relationships and biomedical research in the dog species.
Using high-throughput sequencing to investigate the factors structuring genomic variation of a Mediterranean grasshopper of great conservation concern
Authors: González-Serna María José , Cordero Pedro J. , Ortego Joaquín
Published: September 2018

Inferring the demographic history of species is fundamental for understanding their responses to past climate/landscape alterations and improving our predictions about the future impacts of the different components of ongoing global change. Estimating the time-frame at which population fragmentation took place is also critical to determine whether such process was shaped by ancient events (e.g. past climate/geological changes) or if, conversely, it was driven by recent human activities (e.g. habitat loss). We employed genomic data (ddRAD-Seq) to determine the factors shaping contemporary patterns of genetic variation in the Iberian cross-backed grasshopperDociostaurus crassiusculus, an endangered species with limited dispersal capacity and narrow habitat requirements. Our analyses indicate the presence of two ancient lineages and three genetic clusters resulted from historical processes of population fragmentation (~18–126 ka) that predate the Anthropocene. Landscape genetic analyses indicate that the limits of major river basins are the main geographical feature explaining large-scale patterns of genomic differentiation, with no apparent effect of human-driven habitat fragmentation. Overall, our study highlights the importance of detailed phylogeographic, demographic and spatially-explicit landscape analyses to identify evolutionary significant units and determine the relative impact of historicalvs. anthropogenic factors on processes of genetic fragmentation in taxa of great conservation concern.
Clinical evaluation of rapid fluorescent diagnostic immunochromatographic test for influenza A virus (H1N1)
Authors: Yu Seung-Taek , Thi Bui Cuc , Kim Do Thi Hoang , V. T. Nguyen Anh , Thi Trinh Thuy Tien , Yeo Seon-Ju
Published: September 2018

Rapid diagnostic tests (RDTs) have been developed to detect influenza A virus for the swift diagnosis and management of patients. However, despite the simplicity and convenience, the low sensitivity of RDTs remains a limitation for their use in point of care testing (POCT). In this study, we developed a rapid fluorescent immunochromatographic strip test (FICT) and the performance of FICT was confirmed by the real-time reverse transcription-polymerase chain reaction (rRT-PCR) of H1N1, compared with that of RDT. The limit of detection (LOD) of FICT was improved by 16-fold compared to RDT. FICT showed 85.29% sensitivity (29/34) (95% Confidence Interval [95% CI]: 68.94 to 95.05), 100% specificity (26/26) (95% CI: 86.78 to 100.00), and a strong correlation (kappa; 0. 92) compared with rRT-PCR (20 ≤ Ct ≤ 36). In contrast, RDT (Standard Diagnostics [SD] BIOLINE Influenza Ag A/ B/ A(H1N1) Pandemic) showed 55.88% sensitivity (19/34) (95% CI: 37.87 to 72.82), 100% specificity (26/26) (95% CI: 77.07 to 100), and had a fair correlation with rRT-PCR (kappa; 0. 75). FICT had better sensitivity than RDT (P < 0.01; McNemar’s test). Therefore, FICT has the potential to improve the quality of current rapid POCT for the diagnosis of influenza A/H1N1 infection.
Maximum blink interval is associated with tear film breakup time: A new simple, screening test for dry eye disease
Authors: Inomata Takenori , Iwagami Masao , Hiratsuka Yoshimune , Fujimoto Keiichi , Okumura Yuichi , Shiang Tina , Murakami Akira
Published: September 2018

The prevalence of dry eye disease (DED) is increasing worldwide, and its diagnosis often needs dedicated reagents and machines. We investigated the usefulness of maximum blink interval (MBI) (the length of time that participants could keep their eyes open) in screening for DED. This cross-sectional study included 292 patients (194 with DED and 98 without DED) recruited between September 2016 and September 2017. We compared the MBI between patients with and without DED; examined correlations between MBI and other clinical features of DED, including subjective symptoms (Dry Eye-Related Quality-of-Life Score), tear film breakup time (TFBUT), cornea fluorescence score (CFS), and Schirmer test I value; and determined the optimal cutoff value of MBI to suspect DED using a receiver operating characteristic (ROC) analysis. The MBI was significantly shortened in DED group compared to the non-DED group (10.0 ± 9.1 vs. 24.3 ± 38.2 seconds, p < 0.001). TFBUT was strongly positively correlated with MBI (r = 0.464), whereas CFS was negatively correlated with MBI (r = −0.273). The area under the ROC curve was 0.677, and the optimal MBI cutoff value was 12.4 seconds, providing a sensitivity of 82.5% and specificity of 51.0% to suspect DED. In conclusion, MBI may be a simple, useful test for screening DED.
A new sauropodiform dinosaur with a ‘sauropodan’ skull from the Lower Jurassic Lufeng Formation of Yunnan Province, China
Authors: Zhang Qian-Nan , You Hai-Lu , Wang Tao , Chatterjee Sankar
Published: September 2018

The Early Jurassic Lufeng Formation of Yunnan Province in southwestern China is one of the best fossil localities in the world for understanding the early radiation of sauropodomorph dinosaurs. It has yielded a rich assemblage of complete and three-dimensionally preserved skeletons of herbivorous dinosaurs that provide crucial morphological information for systematic and evolutionary studies. Here we describe a new taxon, Yizhousaurus sunae gen. et sp. nov., represented by a nearly complete skeleton with an exquisitely preserved skull and mandible. Yizhousaurus is distinguished from other non-sauropodan sauropodomorphs by a unique combination of plesiomorphic and apomorphic features, which increases our understanding of the anatomical variation on the relatively conservative ‘prosauropod’ cranial plan. Phylogenetic analysis resolves Yizhousaurus as a sauropodiform, showcasing a mosaic character suite combining plesiomorphic states in the postcranial skeleton with some more ‘sauropodan’-like features in the skull. Furthermore, Yizhousaurus is placed closer to the base of Sauropoda than other non-sauropodan sauropodomorphs currently known from the Lufeng Formation, adding another taxon to enrich the Lower Jurassic Lufeng dinosaur fauna.
Tin-palladium supported on alumina as a highly active and selective catalyst for hydrogenation of nitrate in actual groundwater polluted with nitrate
Authors: Hirayama Jun , Kamiya Yuichi
Published: September 2018

We developed SnPd/Al2O3 showing high catalytic performance for the hydrogenation of NO3− in actual groundwater polluted with NO3−.
A comprehensive approach providing a new synthetic route for bimetallic electrocatalysts via isoPOMs [M/Rh(Cp*)4W8O32] (M = Rh (1) and Ir (2))
Authors: Singh Vikram , Ma Pengtao , Drew Michael G. B. , Wang Jingping , Niu Jingyang
Published: September 2018

Efficient electrocatalysts (3 and 4) obtained via pathway mediated by POM@NFs (1 and 2) with comparable HER activity to Pt/C: Heterobimetallic nanocomposite materials for advanced catalytic applications.
Lacto-fermented sauerkraut improves symptoms in IBS patients independent of product pasteurisation – a pilot study
Authors: Nielsen Elsa Sandberg , Garnås Eirik , Jensen Kathrine Juul , Hansen Lars Hestbjerg , Olsen Peder Sandvold , Ritz Christian , Krych Lukasz , Nielsen Dennis Sandris
Published: September 2018

Lacto-fermented sauerkraut contains a natural variety of lactic acid bacteria (LAB) and has not previously been studied in the treatment of irritable bowel syndrome (IBS).
Few-layer bismuthene for ultrashort pulse generation in a dissipative system based on an evanescent field
Authors: Chai Tong , Li Xiaohui , Feng Tianci , Guo Penglai , Song Yufeng , Chen Yunxiang , Zhang Han
Published: September 2018

A dissipative soliton Yb-doped mode-locked fiber laser at 1 μm regime with bismuthene saturable absorber via an evanescent field interaction.
Self-scrolling MoS2 metallic wires
Authors: Wang Zegao , Wu Hong-Hui , Li Qiang , Besenbacher Flemming , Zeng Xiao Cheng , Dong Mingdong
Published: September 2018

Herein, the properties of quasi-1D MoS2 nanoscrolls are systemically studied via experiment and theoretical simulation demonstrating that MoS2 can transit from semiconductor to metal by self-scrolling.
Alkenylazaarenes as dipolarophiles in 1,3-dipolar cycloaddition of nitrones: regioselectivity-switchable and highly diastereoselective synthesis of multisubstituted isoxazolidines
Authors: Tong Mengchao , Zhang Yong , Qin Cong , Fu Yiwei , Liu Yonghai , Li Hao , Wang Wei
Published: September 2018

Metal free 1,3-dipolar cycloaddition between alkenylazaarenes and nitrones has been developed for the synthesis of 4-substituted isoxazolidines and 5-substituted isoxazolidines in good yields and selectivities.
Silver-catalyzed decarboxylative cascade radical cyclization of tert-carboxylic acids and o-(allyloxy)arylaldehydes towards chroman-4-one derivatives
Authors: Hu Hao , Chen Xiaolan , Sun Kai , Wang Junchao , Liu Yan , Liu Hui , Yu Bing , Sun Yuanqiang , Qu Lingbo , Zhao Yufen
Published: September 2018

A convenient silver-catalyzed decarboxylative cascade radical cyclization of tertiary carboxylic acids and o-(allyloxy)arylaldehydes was developed to synthesize 3-alkyl-substituted chroman-4-one derivatives.
High energetic polymeric nitrogen sheet confined in a graphene matrix
Authors: Niu Shifeng , Liu Shijie , Liu Bo , Shi Xuhan , Liu Shuang , Liu Ran , Yao Mingguang , Cui Tian , Liu Bingbing
Published: September 2018

The hybrid material (A7@graphene system) provides a highly promising method for the capture and storage of polymeric nitrogen in a controllable way.
Coptisine suppresses tumor growth and progression by down-regulating MFG-E8 in colorectal cancer
Authors: Cao Qianyu , Hong Shengwei , Li Yuanyuan , Chen Heng , Shen Yining , Shao Kang , Lu Mengjie , Dai Hui , Ma Shitang , Dai Guoliang
Published: September 2018

Treating colorectal cancer (CRC) continues to be a clinical challenge. Coptisine, an alkaloid derived from Coptis chinensis Franch. shows toxic effects on CRC cells, but its underlying mechanism remains elusive.
Tautomerism and antioxidant activity of some 4-acylpyrazolone-based Schiff bases: a theoretical study
Authors: Orabi Esam A.
Published: September 2018

Computational investigations reveal that 4-acylpyrazolone Schiff bases adopt the amine-one structure and that ionization potentials provide a measure for their antioxidant activity.
Correction: Solution-processed Cu2XSnS4 (X = Fe, Co, Ni) photo-electrochemical and thin film solar cells on vertically grown ZnO nanorod arrays
Authors: Ghosh Anima , Chaudhary Dhirendra K. , Biswas Amrita , Thangavel Rajalingam , Udayabhanu G.
Published: September 2018

Correction for ‘Solution-processed Cu2XSnS4 (X = Fe, Co, Ni) photo-electrochemical and thin film solar cells on vertically grown ZnO nanorod arrays’ by Anima Ghosh et al., RSC Adv., 2016, 6, 115204–115212.
The association between MMP-1 gene rs1799750 polymorphism and knee osteoarthritis risk
Authors: Geng Rui , Xu Yuansheng , Hu Wenhao , Zhao Hui
Published: September 2018

Matrix metalloproteinase 1 (MMP-1) degrades cartilage, which may result in osteoarthritis (OA) development. Several studies have explored the association between MMP-1 gene rs1799750 polymorphism and OA in different populations. However, the results are inconsistent. The aim of this case–control study was to investigate the association between MMP-1 gene rs1799750 polymorphism and knee OA in a Chinese population. The present study included 308 cases and 404 controls. Genotyping was performed using standard polymerase chain reaction and restriction fragment length polymorphism. The present study found that 2G2G genotype (2G2G vs 1G1G: OR & 95% CI, 2.28 (1.47–3.53), P<0.001; 2G2G + 1G2G vs 1G1G: OR & 95% CI, 1.61 (1.15–2.24), P=0.005; 2G2G vs 1G2G + 1G1G: OR & 95% CI, 1.84 (1.26–2.68), P=0.002) or 2G allele carriers (2G vs 1G: OR & 95% CI, 1.48 (1.20–1.83), P<0.001) of MMP-1 gene rs1799750 polymorphism increased the risk of OA. In conclusion, this case–control study confirms that MMP-1 gene rs1799750 polymorphism increases the risk of knee OA in Chinese Han population.
Calculation of wooden beams on the stability of a flat bending shape enhancement
Authors: Chepurnenko Anton , Ulianskaya Vera , Yazyev Serdar , Zotov Ivan
Published: September 2018

Flat bending stability problem of constant rectangular cross section wooden beam, loaded by a distributed load is considered. Differential equation is provided for the cases when load is located not in the center of gravity. The solution of the equation is performed numerically by the method of finite differences. For the case of applying a load at the center of gravity, the problem reduces to a generalized secular equation. In other cases, the iterative algorithm developed by the authors is implemented, in the Matlab package. A relationship between the value of the critical force and the position of the load application point is obtained. A linear approximating function is selected for this dependence.
Analyzing the influence of the disk motion on longitudinal oscillations of a beam with rheological properties
Authors: Kalmova Maria , Pavlov Georgy
Published: September 2018

The paper gives the analysis of the influence of longitudinal oscillations of a beam, which is caused by a circular hard disk motion along the beam, on the mode of disk motion. The problem of rolling the disk on the plane in its various formulations has been investigated by different researchers as well as by the authors of this paper. The paper considers two variants of properties of the beam material: an elastic beam and a viscoelastic beam, which fits the Kelvin rheological model and has relaxation and creep properties. When solving the problem, the Fourier method is used as a method of separation of variables. When examining the beam, and assuming it as hereditary deformable, a rheological force of the reaction is introduced, this depends on both on longitudinal strains and on the rate of these strains The result is presented as functions of time which are adaptable for numerical integration. It is shown that oscillations of a rheological beam are produced by a moving disk and can be considered as self-oscillations.
The task of direct piezoeffect for a bi-morth plate
Authors: Shlyahin Dmitriy , Ratmanova Olesya
Published: September 2018

The research focuses on the dynamic axisymmetric task for a round bi-morph structure consisting of a metal support plate and a piezoceramic axially polarized plate. Its bending oscillations are carried out because of the actions of mechanical load (normal stresses) on its end surface, which is an arbitrary time and radial coordinate function. The rigid and hinged support of the plate cylindrical surface is taken into account. The value of the induced field is calculated by determining the potential on the metal support plate. To solve the task of the theory of the elasticity in a three-dimensional model, the authors apply the Hankel finite integral transformations along the axial coordinate and generalized transformation along the radial variable. Besides, at each stage of the study the standardization procedure is carried out. In the first case it is connected with the use of mixed boundary conditions along the radial coordinate to the mixed form, and in the second case heterogeneous boundary conditions are presented as homogenious. The obtained calculation ratios make it possible to determine the optimal thickness of the piezoceramic plate, which allows to make the most effective transformation of the external mechanical effect into an electrical signal. In addition, it is possible to determine changing characteristics of electromagnetic field according to the height of the piezoceramic plate. This principle can be used in the calculation and design of bi-morph systems with graded-varying thickness and rigidity.
Combined Semianalytical and Numerical Static Plate Analysis. Part 1: Formulation of the Problem and Approximation Models
Authors: Negrozov Oleg , Akimov Pavel , Mozgaleva Marina
Published: September 2018

The distinctive paper is devoted to solution of multipoint (particularly, two-point) boundary problem of plate analysis (Kirchhoff model) based on combined application of finite element method (FEM) and discrete-continual finite element method (DCFEM). As is known the Kirchhoff-Love theory of plates is a two-dimensional mathematical model that is normally used to determine the stresses and deformations in thin plates subjected to forces and moments. The given domain, occupied by considering structure, is embordered by extended one. The field of application of DCFEM comprises fragments of structure (subdomains) with regular (constant or piecewise constant) physical and geometrical parameters in some dimension (“basic” dimension). DCFEM presupposes finite element mesh approximation for non-basic dimension of extended domain while in the basic dimension problem remains continual. FEM is used for approximation of all other subdomains (it is convenient to solve plate bending problems in terms of displacements). Discrete (within FEM) and discrete-continual (within DCFEM) approximation models for subdomains are under consideration.
Calculation of thin isotropic shells beyond the elastic limit by the method of elastic solutions
Authors: Astakhova Avgustina
Published: September 2018

The paper focuses on the model of calculation of thin isotropic shells beyond the elastic limit. The determination of the stress-strain state of thin shells is based on the small elastic-plastic deformations theory and the elastic solutions method. In the present work the building of the solution based on the equilibrium equations and geometric relations of linear theory of thin shells in curved coordinate system α and β, and the relations between deformations and forces based on the Hirchhoff-Lave hypothesis and the small elastic-plastic deformations theory are presented. Internal forces tensor is presented in the form of its expansion to the elasticity tensor and the additional terms tensor expressed the physical nonlinearity of the problem. The functions expressed the physical nonlinearity of the material are determined. The relations that allow to determine the range of elastic-plastic deformations on the surface of the present shell and their changing in shell thickness are presented. The examples of the calculation demonstrate the convergence of elastic-plastic deformations method and the range of elastic-plastic deformations in thickness in the spherical shell. Spherical shells with the angle of half-life regarding 90 degree vertical symmetry axis under the action of equally distributed ring loads are observed.
Assessment of Durability Indicators of Flexible Pavements on the Basis of the Mechanical-Statistical Method
Authors: Tiraturyan Artem , Uglova Evgeniya
Published: September 2018

The article gives a brief overview of the developed mechanical-statistical method of assessment of durability indicators of flexible pavements. It contains the main prerequisites of the study and the results of the study of the change in the indicators of mathematical expectation and variance of the main structural parameters of flexible pavements while in operation. Implementation of this method is illustrated with the example of calculation of the gamma-percentile remaining service life and operating life of the pavement.
Stress-strain state analysis of structures based on the monitoring data
Authors: Sidorov Dmitriy , Dorozhinskiy Vladimir
Published: September 2018

Advances in construction technology result in increased complexity and multi-functionality of modern buildings and structures. This is especially true for unique structures with large spans and heights. Based on the current standards, such structures must be monitored as well as the stress-strain state (SSS) of supporting structures. In addition, the SSS must be continuously checked during operation. Indeed, facilities of higher complexity are more prone to errors or discrepancies, which can reduce the reliability of some structures as well as the whole system. This can be caused by human factor, variability of external and internal forces and impacts, specifics of erection and installation, and many other reasons. Therefore, unique buildings and structures must be built with monitoring systems or operated under routine inspection. This way we can determine if the behavior of the erected structure complies with the standards and regulations.
Calculation of plates in a geometrically nonlinear setting with the use of generalized equations of finite difference method
Authors: Uvarova Natalia , Gabbasov Radek
Published: September 2018

The article proposes a numerical method and an algorithm for analysis rectangular flexible plates in a geometrically nonlinear formulation. The generalized equations of the method of finite differences (MD) are used to solve the problem within the integrable region taking into account the discontinuities of the desired function, its first derivative and the right part of the original differential equation. Solving differential equations of the problem, composed with respect to the desired functions of deflection and stress are reduced to the 4th differential equations of the second order, which are solved numerically. As an example, a square plate loaded with a uniformly distributed load is considered. The results of the calculation with a minimum number of partitions are compared with the known analytical solution of A. S. Volmir [1] and indicate the possibility of using the numerical method for solving problems in a nonlinear formulation.
Verification of the reinforced concrete beam model based on the results of a full-scale experimental study
Authors: Mkrtychev Oleg , Andreev Mikhail
Published: September 2018

The article presents the results of a numerical experiment consisting in a bending test of a reinforced concrete beam and comparison of the results obtained with the results of full-scale experiments. In most cases, it is not possible to adequately consider all types of nonlinearities when using simplified bar and plate elements. The problem can be solved by using more detailed computational models with solid finite elements, allowing to consider directly the joint behavior of reinforcing bars and concrete. The studies were carried out in the LS-DYNA software package, which implemented the nonlinear concrete model – Continuous Surface Cap Model (CSCM). This model allows to consider the joint behavior of reinforcing bars and concrete, using bar (for reinforcing bars) and solid (for concrete) finite elements, thereby helping to overcome existing shortcomings in the diagrams of concrete behavior. As an object of modeling, a reinforced concrete statically determinable beam of rectangular section with dimensions of 1,000 х 50 х 100 (h) mm is considered. The conducted studies showed that the ultimate load on the beam based on the results of numerical modeling is quite consistent with the experimental value (8.5% discrepancy). The arrangement of cracks and the fracture pattern obtained from the modeling results in the LS-DYNA software package are in good agreement with the results of the tests. The LS-DYNA software package will allow correct solid modeling of bending reinforced concrete elements with specification of nonlinear diagrams of concrete and reinforcing bars deformation and can be used for research, calculation and design of reinforced concrete elements of buildings and structures.
Problem of modelling a layered medium taking into account the creep of its materials
Authors: Bobyleva Tatiana , Shamaev Alexei
Published: September 2018

Problems for heterogeneous materials arise in many areas of construction. This article deals with elastic-creeping layered composite materials. Relations of the theory of linear heredity of Boltzmann-Volterra are accepted. Creep kernels are given by the sum of a finite number of decreasing exponential functions. Such sum of several exponential functions can be used to approximate the experimental data for the creep and relaxation kernels with a given accuracy. It is obtained that the resulting homogeneous medium is described by a creep kernel, which is also a sum of decreasing exponential functions. Algorithm for the rapid and accurate calculation of averaged creep kernels of a homogenized material is proposed. Some qualitative properties of the received homogenized model are analyzed.
Deviatoric section shape functions for materials exhibiting dependence on shear-to-axial yield stress ratio
Authors: Szwed Aleksander
Published: September 2018

Proposal of a class of smooth functions describing shape of the deviatoric section of the failure surface of isotropic materials is given. Their convexity is investigated and the resultant restrictions to the free parameters are derived. Applications to pressure sensitive or insensitive materials as yield criteria are shown. Discussion of calibration of material parameters is carried out and dependence of the failure surface on the shear-to-axial yield stress ratio is demonstrated.
Stress-deformed state in the plane domain boundary angle cutout zone
Authors: Frishter Ludmila
Published: September 2018

Studying the stress-deformed state of structures with complex-shaped boundary is an urgent task for designing and developing numerical and analytical methods of constructions, buildings and structures research. Stress concentration due to geometrically nonlinear shape of the boundaries – cutouts, notches, causes stress, deformation zones with significant magnitudes and gradients. Theoretical analysis of the boundary angle cutout domain stress-deformed state (SDS) under rupturing forced deformations comes down to studying singular solutions of elasticity theory homogeneous problem with power-type specifics. Novelty of the studies given herein is that the SDS in the vicinity of an irregular boundary point – the domain boundary angle cutout vertex, is characterized by stress limit values similar to stress intensity coefficients when applying force criteria in fracture mechanics. Asymptotics of elastic problem solution in the random opening boundary angle cutout domain is written using the stress limit values. Obtained asymptotic expression for elasticity theory plane problem solution allows to analyze the SDS of the domain boundary angle cutout zone as a function of the domain cutout opening angle, mechanical characteristics and eigenvalues of elasticity boundary-value problem in case of stresses homogeneous boundary conditions.
Reduction of the bearing capacity of a thin-walled steel beam-column as a result of uniform corrosion
Authors: Glinicka Aniela , Maciąg Michał
Published: September 2018

The paper presents the analysis of the load-bearing capacity of thin-walled steel bars such as beam-column. It was assumed that the rods are subject to uniformly distributed surface corrosion in the atmosphere over their entire length. As a result of corrosion, the mass loss of these rods, i.e. the thickness of the cross-sectional walls of the rod are evenly reduced. Therefore, the dependence of the critical force - the eccentricity changes. The theory of stability of thin-walled bars was used to calculate the load capacity of the rod. To calculate changes in the load capacity of the rod, an interactive relationship was used that combines compression with bending. A calculation example of the load capacity of an eccentrically compressed rod with a “C” section which has been corroded has been presented.
Vibrations of a Timoshenko beam on an inertial foundation under a moving load
Authors: Ataman Magdalena
Published: September 2018

In the paper vibrations of the Timoshenko beam on an inertial foundation subjected to a moving force are discussed. Considered model of the inertial foundation is described by three parameters. They take into account elasticity, shear and inertia of the subgrade. In the literature such model of the subgrade is called Vlasov or Vlasov-Leontiev model. The Timoshenko beam is traversed by a concentrated load, moving with uniform speed. Response of the beam is found from the governing equations of motion of the problem. Problem of forced vibrations and problem of free vibrations of the beam are solved. Damping of the system is taken into consideration. Solution of the problem is illustrated by numerical example.
Cavitation research results of hydroturbine impeller blades and their analysis
Authors: Romanov Alexey , Evdokimov Sergey , Seliverstov Vladimir
Published: September 2018

Abstract. Cavitation erosion affects the hydropower plants operation mode, destroys the surface of water-conducting way, affects the efficiency coefficient as well as the turbine output. The most common damage is observed on water-conducting ways having poor streamline shape, various ledges, irregularities along the water flow. Disruptive cavitations are formed initially on the rotation axes of vortexes, and the caverns of disruptive cavitation develop with the period subordinating the Strouhal Law. One of the methods of cavitational erosion field studies is the method of obtaining high-speed cavitational erosion of metal plates, which has low resistance to cavitation mechanical effects. It provides an opportunity to determine erosion degree and intensity at different modes of hydropower plants operation. The paper demonstrates the results of studying the cavitational erosion process of hydroturbine impeller blades of Zhiguli Hydroelectric Station (HS). Cavitation tests are conducted for three operating modes. Technological peculiarities are also described. The paper presents results of turbine blades of Unit 5 for three operation modes. The destruction areas of impeller blades peripheral edges are visualized. The study provides the results of field and laboratory cavitation tests of hydroturbine elements that serve as recommendations for repairing and restoration of damaged hydroelectric units of Zhiguli HS.