bluuebunny/crossref_metadata_2025 huggingface dataset:
Remotely-sensed productivity clusters capture global biodiversity patterns
Authors: Coops Nicholas C. , Kearney Sean P. , Bolton Douglas K. , Radeloff Volker C.
Published: October 2018

Ecological regionalisations delineate areas of similar environmental conditions, ecological processes, and biotic communities, and provide a basis for systematic conservation planning and management. Most regionalisations are made based on subjective criteria, and can not be readily revised, leading to outstanding questions with respect to how to optimally develop and define them. Advances in remote sensing technology, and big data analysis approaches, provide new opportunities for regionalisations, especially in terms of productivity patterns through both photosynthesis and structural surrogates. Here we show that global terrestrial productivity dynamics can be captured by Dynamics Habitat Indices (DHIs) and we conduct a regionalisation based on the DHIs using a two-stage multivariate clustering approach. Encouragingly, the derived clusters are more homogeneous in terms of species richness of three key taxa, and of canopy height, than a conventional regionalisation. We conclude with discussing the benefits of these remotely derived clusters for biodiversity assessments and conservation. The clusters based on the DHIs explained more variance, and greater within-region homogeneity, compared to conventional regionalisations for species richness of both amphibians and mammals, and were comparable in the case of birds. Structure as defined by global tree height was also better defined by productivity driven clusters than conventional regionalisations. These results suggest that ecological regionalisations based on remotely sensed metrics have clear advantages over conventional regionalisations for certain applications, and they are also more easily updated.
Data-driven Classification of the 3D Spinal Curve in Adolescent Idiopathic Scoliosis with an Applications in Surgical Outcome Prediction
Authors: Pasha Saba , Flynn John
Published: October 2018

Adolescent idiopathic scoliosis (AIS) is a three-dimensional (3D) deformity of the spinal column. For progressive deformities in AIS, the spinal fusion surgery aims to correct and stabilize the deformity; however, common surgical planning approaches based on the 2D X-rays and subjective surgical decision-making have been challenged by poor clinical outcomes. As the suboptimal surgical outcomes can significantly impact the cost, risk of revision surgery, and long-term rehabilitation of adolescent patients, objective patient-specific models that predict the outcome of different treatment scenarios are in high demand. 3D classification of the spinal curvature and identifying the key surgical parameters influencing the outcomes are required for such models. Here, we show that K-means clustering of the isotropically scaled 3D spinal curves provides an effective, data-driven method for classification of patients. We further propose, and evaluate in 67 right thoracic AIS patients, that by knowing the patients’ pre-operative and early post-operation clusters and the vertebral levels which were instrumented during the surgery, the two-year outcome cluster can be determined. This framework, once applied to a larger heterogeneous patient dataset, can further isolate the key surgeon-modifiable parameters and eventually lead to a patient-specific predictive model based on a limited number of factors determinable prior to surgery.
Turning date palm fronds into biocompatible mesoporous fluorescent carbon dots
Authors: Kavitha T. , Kumar S.
Published: October 2018

Here, we demonstrate the synthesis of mesoporous carbon dots (Cdot) from date palm fronds and their excellent excitation wavelength-independent photoluminescence (PL), with high photo- and storage-stability, superior biocompatibility and thermal and electrical conductivity for the first-time by a simple, green, one-step carbonization method. Interestingly, the as-obtained Cdot manifest the spherical shape of about 50 nm average diameter having surface mesopores of size less than 10 nm with sp2 hybridized carbon. The as-synthesised mesoporous Cdot, first of its kind, evince yellow-green PL (preferred over blue PL for biological applications) around 450 nm under excitation wavelength range of 320–420 nm with absolute quantum yield of 33.7% exhibiting high photo- and storage-stability. The thermal and electrical conductivity of Cdot/water nanofluids without any surfactants is illustrated. Application of Cdot as interfacial material in organic photovoltaic cell is manifested. The Cdot exhib visible sunlight driven photocatalytic and antibacterial activity. Mesoporous Cdot further reveal excellent biocompatibility with fibroblast cell (greater than 95% viability). The novelty of this study in the formation of multifunctional mesoporous Cdot from date palm fronds could inspire both research and industrial interests in the synthesis of biomass-derived Cdot and their application in a wide array of fields.
Effects of metformin on congenital muscular dystrophy type 1A disease progression in mice: a gender impact study
Authors: Fontes-Oliveira Cibely C. , M. Soares Oliveira Bernardo , Körner Zandra , M. Harandi Vahid , Durbeej Madeleine
Published: October 2018

Congenital muscular dystrophy with laminin α2 chain-deficiency (LAMA2-CMD) is a severe muscle disorder with complex underlying pathogenesis. We have previously employed profiling techniques to elucidate molecular patterns and demonstrated significant metabolic impairment in skeletal muscle from LAMA2-CMD patients and mouse models. Thus, we hypothesize that skeletal muscle metabolism may be a promising pharmacological target to improve muscle function in LAMA2-CMD. Here, we have investigated whether the multifunctional medication metformin could be used to reduce disease in the dy2J/dy2J mouse model of LAMA2-CMD. First, we show gender disparity for several pathological hallmarks of LAMA2-CMD. Second, we demonstrate that metformin treatment significantly increases weight gain and energy efficiency, enhances muscle function and improves skeletal muscle histology in female dy2J/dy2J mice (and to a lesser extent in dy2J/dy2J males). Thus, our current data suggest that metformin may be a potential future supportive treatment that improves many of the pathological characteristics of LAMA2-CMD.
Previously unknown quasicrystal periodic approximant found in space
Authors: Bindi Luca , Pham Joyce , Steinhardt Paul J.
Published: October 2018

We report the discovery of Al34Ni9Fe2, the first natural known periodic crystalline approximant to decagonite (Al71Ni24Fe5), a natural quasicrystal composed of a periodic stack of planes with quasiperiodic atomic order and ten-fold symmetry. The new mineral has been approved by the International Mineralogical Association (IMA 2018-038) and officially named proxidecagonite, which derives from its identity to periodic approximant of decagonite. Both decagonite and proxidecagonite were found in fragments from the Khatyrka meteorite. Proxidecagonite is the first natural quasicrystal approximant to be found in the Al-Ni-Fe system. Within this system, the decagonal quasicrystal phase has been reported to transform at ~940 °C to Al13(Fe,Ni)4, Al3(Fe,Ni)2 and the liquid phase, and between 800 and 850 °C to Al13(Fe,Ni)4, Al3(Fe,Ni) and Al3(Fe,Ni)2. The fact that proxidecagonite has not been observed in the laboratory before and formed in a meteorite exposed to high pressures and temperatures during impact-induced shocks suggests that it might be a thermodynamically stable compound at high pressure. The most prominent structural motifs are pseudo-pentagonal symmetry subunits, such as pentagonal bipyramids, that share edges and corners with trigonal bipyramids and which maximize shortest Ni–Al over Ni–Ni contacts.
Fast confocal fluorescence imaging in freely behaving mice
Authors: Dussaux Clara , Szabo Vivien , Chastagnier Yan , Fodor Jozsua , Léger Jean-François , Bourdieu Laurent , Perroy Julie , Ventalon Cathie
Published: October 2018

Fluorescence imaging in the brain of freely behaving mice is challenging due to severe miniaturization constraints. In particular, the ability to image a large field of view at high temporal resolution and with efficient out-of-focus background rejection still raises technical difficulties. Here, we present a novel fiberscope system that provides fast (up to 200 Hz) background-free fluorescence imaging in freely behaving mice over a field of view of diameter 230 μm. The fiberscope is composed of a custom-made multipoint-scanning confocal microscope coupled to the animal with an image guide and a micro-objective. By simultaneously registering a multipoint-scanning confocal image and a conventional widefield image, we subtracted the residual out-of-focus background and provided a background-free confocal image. Illumination and detection pinholes were created using a digital micromirror device, providing high adaptability to the sample structure and imaging conditions. Using this novel imaging tool, we demonstrated fast fluorescence imaging of microvasculature up to 120 μm deep in the mouse cortex, with an out-of-focus background reduced by two orders of magnitude compared with widefield microscopy. Taking advantage of the high acquisition rate (200 Hz), we measured red blood cell velocity in the cortical microvasculature and showed an increase in awake, unrestrained mice compared with anaesthetized animals.
Obesity-induced pancreatopathy in rats is reversible after bariatric surgery
Authors: Rebours Vinciane , Garteiser Philippe , Ribeiro-Parenti Lara , Cavin Jean-Baptiste , Doblas Sabrina , Pagé Gwenaël , Bado André , Couvineau Alain , Ruszniewski Philippe , Paradis Valérie , Le Gall Maude , Van Beers Bernard E. , Couvelard Anne
Published: October 2018

Obesity is a risk factor for pancreatic diseases. Bariatric surgery is one of the most efficient treatments of morbid obesity. The aims were to assess pancreatic endocrine and exocrine lesions in obese rats, to analyze effects of bariatric surgery. Sixty-three male Wistar rats were included in five groups: 2 fed with high fat diet (HFD) or normal diet for 3 months, 2 fed with HFD or normal diet for 6 months; 1 group fed with HFD and undergoing bariatric surgery (n = 30). Quantitative MR imaging was performed in HFD6, ND6 and HFD3-BS. Pancreas specimens were analyzed after sacrifice for adipocyte infiltration, fibrosis, acinar-ductal metaplasia, abnormality of Langerhans islets (HHF: hypertrophy, hypervascularisation, fibrosis), and hemosiderin deposits in acinar or endocrine locations. We found that HFD6 rats had more fibro-inflammatory islets (P = 0.0139) and acinar-ducal metaplasia (P = 0.0843) than HFD3 rats. Rats with HFD3+6 had more fibro-inflammatory islets (P < 0.0001), hemosiderin deposits (p < 0.0001), fat infiltration (P = 0.0008) and acinar-ductal metaplasia lesions (P = 0.0424). Weight increase was associated with glycoregulation abnormalities (r = 0.44, P = 0.08) and adipocyte infiltrations (P = 0.009). After surgery, less fibro-inflammatory islets (P = 0.0004), fat and iron infiltrates (P = 0.005 and P = 0.06), and acino-ductal metaplasia (P = 0.05) were observed compared to HFD6 rats. MR image quantifications revealed increased elasticity, fat fraction, and R2 and a decreased elasticity wave dispersion coefficient in the high fat groups that reversed after surgery. MRI parameters were in strong correlation with respective histological counterparts. In conclusion, obese rats develop pancreatic inflammatory lesions with acinar-ductal metaplasia in acinar location and the endocrine-exocrine interface. These changes can be prevented by bariatric surgery. Quantitative MR imaging is accurate in identifying early pancreatic lesions.
Fast Optical Sectioning for Widefield Fluorescence Mesoscopy with the Mesolens based on HiLo Microscopy
Authors: Schniete Jan , Franssen Aimee , Dempster John , Bushell Trevor J , Amos William Bradshaw , McConnell Gail
Published: October 2018

We present here a fast optical sectioning method for mesoscopy based on HiLo microscopy, which makes possible imaging of specimens of up to 4.4 mm × 3 mm × 3 mm in volume in under 17 hours (estimated for a z-stack comprising 1000 images excluding computation time) with subcellular resolution throughout. Widefield epifluorescence imaging is performed with the Mesolens using a high pixel-number camera capable of sensor-shifting to generate a 259.5 Megapixel image, and we have developed custom software to perform HiLo processing of the very large datasets. Using this method, we obtain comparable sectioning strength to confocal laser scanning microscopy (CLSM), with sections as thin as 6.8 ± 0.2 μm and raw acquisition speed of 1 minute per slice which is up to 30 times faster than CLSM on the full field of view (FOV) of the Mesolens of 4.4 mm with lateral resolution of 0.7 μm and axial resolution of 7 μm. We have applied this HiLo mesoscopy method to image fixed and fluorescently stained hippocampal neuronal specimens and a 5-day old zebrafish larva.
Human Wharton’s jelly mesenchymal stem cells protect axotomized rat retinal ganglion cells via secretion of anti-inflammatory and neurotrophic factors
Authors: Millán-Rivero Jose E. , Nadal-Nicolás Francisco M. , García-Bernal David , Sobrado-Calvo Paloma , Blanquer Miguel , Moraleda Jose M. , Vidal-Sanz Manuel , Agudo-Barriuso Marta
Published: October 2018

Mesenchymal stem cell (MSC) transplantation is emerging as an ideal tool to restore the wounded central nervous system (CNS). MSCs isolated from extra-embryonic tissues have some advantages compared to MSCs derived from adult ones, such as an improved proliferative capacity, life span, differentiation potential and immunomodulatory properties. In addition, they are more immunoprivileged, reducing the probability of being rejected by the recipient. Umbilical cords (UCs) are a good source of MSCs because they are abundant, safe, non-invasively harvested after birth and, importantly, they are not encumbered with ethical problems. Here we show that the intravitreal transplant of Wharton´s jelly mesenchymal stem cells isolated from three different human UCs (hWJMSCs) delays axotomy-induced retinal ganglion cell (RGC) loss. In vivo, hWJMSCs secrete anti-inflammatory molecules and trophic factors, the latter alone may account for the elicited neuroprotection. Interestingly, this expression profile differs between naive and injured retinas, suggesting that the environment in which the hWJMSCs are modulates their secretome. Finally, even though the transplant itself is not toxic for RGCs, it is not innocuous as it triggers a transient but massive infiltration of Iba1+cells from the choroid to the retina that alters the retinal structure.
Antimicrobial Activities and Mechanisms of Magnesium Oxide Nanoparticles (nMgO) against Pathogenic Bacteria, Yeasts, and Biofilms
Authors: Nguyen Nhu-Y Thi , Grelling Nathaniel , Wetteland Cheyann Lee , Rosario Romeo , Liu Huinan
Published: October 2018

Magnesium oxide nanoparticle (nMgO) is a light metal based antimicrobial nanoparticle that can be metabolized and fully resorbed in the body. To take advantage of the antimicrobial properties of nMgO for medical use, it is necessary to determine the minimal inhibitory, bactericidal and fungicidal concentrations (MIC, MBC and MFC) of nMgO against prevalent infectious bacteria and yeasts. The objective of this study was to use consistent methods and conditions to reveal and directly compare the efficacy of nMgO against nine prevalent pathogenic microorganisms, including two gram-negative bacteria, three gram-positive bacteria with drug-resistant strains, and four yeasts with drug-resistant strains. The MIC of nMgO varied from 0.5 mg/mL to 1.2 mg/mL and the minimal lethal concentration (MLC) of nMgO at 90% killing varied from 0.7 mg/mL to 1.4 mg/mL against different pathogenic bacteria and yeasts. The most potent concentrations (MPC) of nMgO were 1.4 and/or 1.6 mg/mL, depending on the type of bacteria and yeasts tested. As the concentration of nMgO increased, the adhesion of bacteria and yeasts decreased. Moreover, S. epidermidis biofilm was disrupted at 1.6 mg/mL of nMgO. E. coli and some yeasts showed membrane damage after cultured with ≥0.5 mg/mL nMgO. Overall, nMgO killed both planktonic bacteria and disrupted nascent biofilms, suggesting new antimicrobial mechanisms of nMgO. Production of reactive oxygen species (ROS), Ca2+ ion concentrations, and quorum sensing likely contribute to the action mechanisms of nMgO against planktonic bacteria, but transient alkaline pH of 7 to 10 or increased Mg2+ ion concentrations from 1 to 50 mM showed no inhibitory or killing effects on bacteria such as S. epidermidis. Further studies are needed to determine if specific concentrations of nMgO at MIC, MLC or MPC level can be integrated into medical devices to evoke desired antimicrobial responses without harming host cells.
Flow cytometric analysis of Xenopus laevis and X. tropicalis blood cells using acridine orange
Authors: Sato Kei , Uehara Azusa , Kinoshita Sayaka , Nomura Ikki , Yagi Minami , Tanizaki Yuta , Matsuda-shoji Yu , Matsubayashi Atsushi , Endo Nobuyasu , Nagai Yutaka , Kato Takashi
Published: October 2018

Automated blood cell counters can distinguish cells based on their size and the presence or absence of a nucleus. However, most vertebrates have nucleated blood cells that cannot be counted automatically. We established an alternative automatic method for counting peripheral blood cells by staining cells with the fluorescent dye acridine orange (AO) and analysing cell populations using flow cytometry (FCM). As promising new animal models, we chose Xenopus laevis and three inbred strains of X. tropicalis. We compared the haematological phenotypes, including blood cell types, cell sizes, cellular structure, and erythrocyte lifespans/turnover rate among X. laevis and the three inbred strains of X. tropicalis. Each cell type from X. laevis was sorted according to six parameters: forward- and side-scattered light emission, AO red and green fluorescence intensity, and cellular red and green fluorescence. Remarkably, the erythrocyte count was the highest in the Golden line, suggesting that genetic factors were associated with the blood cells. Furthermore, immature erythrocytes in anaemic X. laevis could be separated from normal blood cells based on red fluorescence intensity. These results show that FCM with AO staining allows for an accurate analysis of peripheral blood cells from various species.
Metabolic profiling of adherence to diet, physical activity and body size recommendations for cancer prevention
Authors: Gu Qianqian , Spinelli John J. , Dummer Trevor B. J. , McDonald Treena E. , Moore Steven C. , Murphy Rachel A.
Published: October 2018

Maintaining a healthy body weight, eating well and being physically active lowers cancer risk by 30%. However, the biology underlying these relationships is not well understood. We examined cross-sectional associations between metabolites and cancer preventive behaviors as well as the relevance to cancer-related pathways among 120 participants (50% men, mean BMI 26.6 kg/m2, mean age 54 years) with no history of smoking or cancer. Participants completed questionnaires, physical measurements and provided blood samples. Non-targeted nuclear magnetic resonance captured 223 metabolite measures. Factor analysis was performed separately for amino acid, fatty acid and lipoprotein groups. Multivariable-adjusted linear regression was used to evaluate associations between cancer preventive recommendations and metabolite-containing factors (p-value < 0.05, false discovery rate <0.20). An inflammation-related metabolite (glycoprotein acetylation) loaded strongly on a factor that was associated with excess adiposity (body fat ≥25% (men) or ≥30% (women) ß (SE) = 0.74 (0.18)) and not meeting physical activity recommendations (ß (SE) = 0.40 (0.20)). Insulin sensitivity-related metabolites including monounsaturated and polyunsaturated fats were lower among participants not meeting recommendations for adiposity, fruits and vegetables and physical activity while branched chain amino acids were higher. Cancer preventive behaviors were associated with complex metabolic signatures, including alterations in pathways known to be involved in cancer pathogenesis.
Selective detections of single-viruses using solid-state nanopores
Authors: Arima Akihide , Tsutsui Makusu , Harlisa Ilva Hanun , Yoshida Takeshi , Tanaka Masayoshi , Yokota Kazumichi , Tonomura Wataru , Taniguchi Masateru , Okochi Mina , Washio Takashi , Kawai Tomoji
Published: October 2018

Rapid diagnosis of flu before symptom onsets can revolutionize our health through diminishing a risk for serious complication as well as preventing infectious disease outbreak. Sensor sensitivity and selectivity are key to accomplish this goal as the number of virus is quite small at the early stage of infection. Here we report on label-free electrical diagnostics of influenza based on nanopore analytics that distinguishes individual virions by their distinct physical features. We accomplish selective resistive-pulse sensing of single flu virus having negative surface charges in a physiological media by exploiting electroosmotic flow to filter contaminants at the Si3N4 pore orifice. We demonstrate identifications of allotypes with 68% accuracy at the single-virus level via pattern classifications of the ionic current signatures. We also show that this discriminability becomes >95% under a binomial distribution theorem by ensembling the pulse data of >20 virions. This simple mechanism is versatile for point-of-care tests of a wide range of flu types.
Fabrication and photoluminescent properties of Tb3+ doped carbon nanodots
Authors: Vostrikova Anna M. , Kokorina Alina A. , Demina Polina A. , German Sergei V. , Novoselova Marina V. , Tarakina Nadezda V. , Sukhorukov Gleb B. , Goryacheva Irina Y.
Published: October 2018

Carbon nanodots (CNDs) doped with Tb ions were synthesized using different synthetic routes: hydrothermal treatment of a solution containing carbon source (sodium dextran sulfate) and TbCl3; mixing of CNDs and TbCl3 solutions; freezing-induced loading of Tb and carbon-containing source into pores of CaCO3 microparticles followed by hydrothermal treatment. Binding of Tb ions to CNDs (Tb-CND coupling) was confirmed using size-exclusion chromatography and manifested itself through a decrease of the Tb photoluminescence lifetime signal. The shortest Tb photoluminescence lifetime was observed for samples obtained by hydrothermal synthesis of CaCO3 microparticles where Tb and carbon source were loaded into pores via the freezing-induced process. The same system displays an increase of Tb photoluminescence via energy transfer with excitation at 320–340 nm. Based on the obtained results, freezing-induced loading of cations into CNDs using porous CaCO3 microparticles as reactors is proposed to be a versatile route for the introduction of active components into CNDs. The obtained CNDs with long-lived emission may be used for time-resolved imaging and visualization in living biological samples where time-resolved and long-lived luminescence microscopy is required.
Design of a novel cell-permeable chimeric peptide to promote wound healing
Authors: Horn Mareike , Neundorf Ines
Published: October 2018

Biological membranes are impermeable to almost all compounds having a molecular weight greater than 500 Da. Recently, cell penetrating peptides (CPPs) as delivery vehicles have attracted great interest in the medical sector for the development of novel therapeutic agents or cosmetic products. Herein, a wound healing promoting sequence, namely Tylotoin, was covalently coupled with a cell penetrating peptide to improve the delivery of Tylotoin across cellular membranes. Indeed, internalization studies indicated that the cellular uptake of these novel peptide conjugates into keratinocytes was significantly improved accompanied by good tolerability. In a scratch wound closure assay used to investigate the wound healing capability, the most promising novel peptide chimera (Tylotoin-sC18*) was found to promote the migration of keratinocytes indicating that the fusion to Tylotoin did not cause any loss in its activity. Even more, proliferative effects on keratinocytes were observed, an important step during the wound healing process. Still more encouraging is the capability of Tylotoin-sC18* to exhibit strong antimicrobial activities since the process of wound healing is often affected by bacterial infections. Owing to their multiple functions, the novel peptide chimera may have potential as future agents for the treatment of infected wounds.
High performance and low temperature coal mine gas sensor activated by UV-irradiation
Authors: kimiagar Salimeh , Najafi Vahid , Witkowski Bartlomiej , Pietruszka Rafal , Godlewski Marek
Published: October 2018

In this work, well-aligned vertical ZnO nanorod (ZnO NRs) on p-type Si substrate was fabricated by a microwave-assisted hydrothermal reactor to study the coal mine methane (CMM) gas sensing properties. The XRD diffraction peaks and Raman spectra of the ZnO NRs confirmed the hexagonal wurtzite structure with strong preferential orientation along the c axis and well crystal quality. SEM analysis showed NRs with 100 nm average diameter and ~600 nm length. The variations of the sensor electrical resistance in the presence of CMM were investigated at different gas concentrations and various temperatures in the dark and under UV light. The selectivity and response time of the sensor to CMM gas were improved under UV irradiation. The optimal operating temperatures were 225 °C and 100 °C in dark and exposing UV-irradiation, respectively. Also the response of ZnO NRs sensor under UV excitation in humid condition was higher. The sensor was more selective to CMM than CO2. The sensor stability was considered by repeating CMM detection for 90 days.
Potassium usnate, a water-soluble usnic acid salt, shows enhanced bioavailability and inhibits invasion and metastasis in colorectal cancer
Authors: Yang Yi , Bae Woo Kyun , Lee Ji-Yoon , Choi Yong Jae , Lee Kyung Hwa , Park Myong-Suk , Yu Young Hyun , Park So-Yeon , Zhou Rui , Taş İsa , Gamage Chathurika , Paik Man-Jeong , Lee Jae Hyuk , Chung Ik Joo , Kim Kyung Keun , Hur Jae-Seoun , Kim Sang Kyum , Ha Hyung-Ho , Kim Hangun
Published: October 2018

Usnic acid (UA), a lichen secondary substance, has considerable anticancer activity in vitro, whereas its effect in vivo is limited. Here, potassium usnate (KU) was prepared by the salinization of UA to enhance its water solubility. KU showed increased bioavailability compared with UA in the tumor, liver, and plasma of a CT26 syngeneic mouse tumor xenograft model after oral administration, as determined by LC-MS/MS analysis. KU exhibited potent anticancer effects on colorectal cancer cells and inhibited liver metastasis in an orthotopic murine colorectal cancer model. KU treatment downregulated the epithelial-mesenchymal markers Twist, Snail, and Slug and the metastasis-related genes CAPN1, CDC42, CFL1, IGF1, WASF1, and WASL in cells and tumor tissues. The present results suggest the potential application of the water-soluble form of UA, KU, in anticancer therapy.
An asparagine/glycine switch governs product specificity of human N-terminal methyltransferase NTMT2
Authors: Dong Cheng , Dong Guangping , Li Li , Zhu Licheng , Tempel Wolfram , Liu Yanli , Huang Rong , Min Jinrong
Published: October 2018

α-N-terminal methylation of proteins is an important post-translational modification that is catalyzed by two different N-terminal methyltransferases, namely NTMT1 and NTMT2. Previous studies have suggested that NTMT1 is a tri-methyltransferase, whereas NTMT2 is a mono-methyltransferase. Here, we report the first crystal structures, to our knowledge, of NTMT2 in binary complex with S-adenosyl-L-methionine as well as in ternary complex with S-adenosyl-L-homocysteine and a substrate peptide. Our structural observations combined with biochemical studies reveal that NTMT2 is also able to di-/tri-methylate the GPKRIA peptide and di-methylate the PPKRIA peptide, otherwise it is predominantly a mono-methyltransferase. The residue N89 of NTMT2 serves as a gatekeeper residue that regulates the binding of unmethylated versus monomethylated substrate peptide. Structural comparison of NTMT1 and NTMT2 prompts us to design a N89G mutant of NTMT2 that can profoundly alter its catalytic activities and product specificities.
Transparent-to-dark photo- and electrochromic gels
Authors: Gonzalez Laura , Liu Chung , Dietrich Bart , Su Hao , Sproules Stephen , Cui Honggang , Honecker Dirk , Adams Dave J. , Draper Emily R.
Published: October 2018

Smart windows in which the transmittance can be controlled on demand are a promising solution for the reduction of energy use in buildings. Windows are often the most energy inefficient part of a building, and so controlling the transmittance has the potential to significantly improve heating costs. Whilst numerous approaches exist, many suitable materials are costly to manufacture and process and so new materials could have a significant impact. Here we describe a gel-based device which is both photo- and electrochromic. The gel matrix is formed by the self-assembly of a naphthalene diimide. The radical anion of the naphthalene diimide can be formed photo or electrochemically, and leads to a desirable transition from transparent to black. The speed of response, low potential needed to generate the radical anion, cyclability of the system, temperature stability and low cost mean these devices may be suitable for applications in smart windows.
Expanding heme-protein folding space using designed multi-heme β-sheet mini-proteins
Authors: D’Souza Areetha , Torres Jaume , Bhattacharjya Surajit
Published: October 2018

Nature has primarily exploited helical proteins, over β-sheets, for heme/multi-heme coordination. Understating of heme–protein structures has motivated the design of heme proteins utilizing coiled-coil helical structure. By contrast, de novo designed β-sheet proteins are less successful. However, designing proteins with discretely folded β-sheet structures encoding specific functions would have great potential for the development of new synthetic molecules e.g. enzymes, inhibitors. Here we report the design and characterization of multi-heme binding four-, six-, eight-, and twelve-stranded β-sheet mini-proteins (<40 amino acids) and proteins. Atomic-resolution structures demonstrate an expected β-sheet structural topology. The designed β-sheet mini-proteins pack or latch multiple hemes with high affnity in versatile orientations either by stacking or sideways, mimicking naturally occuring multi-heme protein conduits. The designed multi-stranded β-sheet heme proteins could serve as a platform for the generation of novel synthetic β-sheet protein mimics.
A MnO2nanosheets–o-phenylenediamine oxidative system for the sensitive fluorescence determination of alkaline phosphatase activity
Authors: Tan Xionghong , Li Zheng , Du Yanlin , Zheng Aixian , Zeng Yongyi , Zhang Xiaolong , Liu Xiaolong , Peng Niancai
Published: October 2018

A MnO2nanosheets–o-phenylenediamine (OPDA) oxidative system was developed for detecting ALP activity selectively, sensitively and conveniently.
pH-Control as a way to fine-tune the Cu/Cu2O ratio in radiation induced synthesis of Cu2O particles
Authors: Li Zhuofeng , Soroka Inna L. , Min Fanyi , Jonsson Mats
Published: October 2018

During the γ-radiation induced synthesis, composition and morphology of Cu–Cu2O precipitate can be tuned by varying the aqueous CuSO4 solution pH in the narrow range from 3.75 to 4.40.
Copper selenide (Cu3Se2 and Cu2−xSe) thin films: electrochemical deposition and electrocatalytic application in quantum dot-sensitized solar cells
Authors: Zhou Ru , Huang Yuanzhang , Zhou Juntian , Niu Haihong , Wan Lei , Li Yuan , Xu Jun , Xu Jinzhang
Published: October 2018

Electrodeposited copper selenide (Cu3Se2 and Cu2−xSe) thin films have been successfully fabricated and demonstrated as promising counter electrodes for QDSCs.
Laser-induced fabrication of porous gold nanoshells
Authors: Park Tae-Hyeon , Jang Du-Jeon
Published: October 2018

Hollow and porous gold nanoshells with high surface-enhanced Raman scattering efficiency have been fabricated through utilizing nanosecond laser irradiation.
Properties of hydrated TiO2and SiO2nanoclusters: dependence on size, temperature and water vapour pressure
Authors: Cuko Andi , Macià Escatllar Antoni , Calatayud Monica , Bromley Stefan T.
Published: October 2018

The stabilities and properties of globally optimised (TiO2)M(H2O)Nand (SiO2)M(H2O)Nclusters withM= 4–16 and a range ofN/Mratios are studied with respect temperature and water vapour pressure. Our systematic study provides a comparative reference for understanding hydration of nano-silica and nano-titania.
Improvement and tuning of the performance of light-healable polymers by variation of the monomer content
Authors: Hughes T. , Simon G. P. , Saito K.
Published: October 2018

High-performing crosslinked epoxy coatings that possess room temperature self-healing ability by the use of a newly synthesised dynamic diamine crosslinker.
Target construction of Co3O4 with an improved layer structure for highly efficient Li-storage properties
Authors: Li Huan-Huan , Xue Yan , Wang Jian-Ji , Zhuo Ke-Lei , Wang Yu-Jie , Bai Guang-Yue
Published: October 2018

An improved layered structure for the conversion-reaction-based anode material of Co3O4 is demonstrated, which displays highly efficient Li-storage properties.
Activation of persulfates by ferrocene–MIL-101(Fe) heterogeneous catalyst for degradation of bisphenol A
Authors: Wang Yu , Guo Weilin , Li Xianghui
Published: October 2018

In this study, a novel and high-performance catalyst ferrocene-MIL-101(Fe) was prepared and used as the heterogeneous catalyst to activate persulfate for bisphenol A degradation.
Batch and fixed-bed column studies for selective removal of cesium ions by compressible Prussian blue/polyurethane sponge
Authors: Chang Shuquan , Fu Heliang , Wu Xian , Liu Chengcheng , Li Zheng , Dai Yaodong , Zhang Haiqian
Published: October 2018

Compressible Prussian blue/polyurethane sponges for selective removal of cesium ions were prepared and detailedly studied via fixed-bed column/batch adsorption experiments.
A synthetic approach to ‘click’ neoglycoprotein analogues of EPO employing one-pot native chemical ligation and CuAAC chemistry
Authors: Lee D. J. , Cameron A. J. , Wright T. H. , Harris P. W. R. , Brimble M. A.
Published: October 2018

The batch-wise variability of commercial erythropoietin (EPO) preparations warrants development of more advanced synthetic methodologies. We have developed a diverse chemical toolkit to prepare ‘click’ neoglycoprotein variants of EPO.
Self-doping small molecular conjugated electrolytes enabled by n-type side chains for highly efficient non-fullerene polymer solar cells
Authors: Wang Shichao , Li Zuojia , Xu Xiaopeng , Zhang Meiling , Zhang Guangjun , Li Ying , Peng Qiang
Published: October 2018

Non-fullerene polymer solar cells, cathode interlayers, small molecular electrolytes, side chain engineering, thickness insensitive.
LiTa2PO8: a fast lithium-ion conductor with new framework structure
Authors: Kim Jaegyeom , Kim Juhyun , Avdeev Maxim , Yun Hoseop , Kim Seung-Joo
Published: October 2018

A new Li-ion conducting oxide, LiTa2PO8 with a novel three-dimensional framework structure was synthesized and characterized.
The role of interface between electron transport layer and perovskite in halogen migration and stabilizing perovskite solar cells with Cs4SnO4
Authors: Zhao Bingxin , Niu Guangda , Dong Qingshun , Liu Jing , Li Nan , Li Jiangwei , Wang Liduo
Published: October 2018

A high electrical field in the depletion region causes severe ionic migration, subsequently inducing ionic migration within perovskite films. After Cs4SnO4 modification, ionic migrations in perovskite films are minimized.
Heliospheric modulation of the interstellar dust flow on to Earth
Authors: Strub P. , Sterken V. J. , Soja R. , Krüger H. , Grün E. , Srama R.
Published: October 2018

Aims. Based on measurements by the Ulysses spacecraft and high-resolution modelling of the motion of interstellar dust (ISD) through the heliosphere we predict the ISD flow in the inner planetary system and on to the Earth. This is the third paper in a series of three about the flow and filtering of the ISD.

Methods. Micrometer- and sub-micrometer-sized dust particles are subject to solar gravity and radiation pressure as well as to interactions with the interplanetary magnetic field that result in a complex size-dependent flow pattern of ISD in the planetary system. With high-resolution dynamical modelling we study the time-resolved flux and mass distribution of ISD and assess the necessary requirements for detection of ISD near the Earth.

Results. Along the Earth orbit the density, speed, and flow direction of ISD depend strongly on the Earth’s position and the size of the interstellar grains. A broad maximum of the ISD flux (~2 × 10−4 m−2 s−1 of particles with radii ≳0.3 μm) occurs in March when the Earth moves against the ISD flow. During this time period the relative speed with respect to the Earth is highest (~60 km s-1), whereas in September when the Earth moves with the ISD flow, both the flux and the speed are lowest (≲10 km s-1). The mean ISD mass flow on to the Earth is approximately 100 kg yr-1 with the highest flux of ~3.5 kg day-1 occurring for about 2 weeks close to the end of the year when the Earth passes near the narrow gravitational focus region of the incoming ISD flow, downstream from the Sun. The phase of the 22-year solar wind cycle has a strong effect on the number density and flow of sub-micrometer-sized ISD particles. During the years of maximum electromagnetic focussing (year 2031 +/− 3) there is a chance that ISD particles with sizes even below 0.1 μm can reach the Earth.

Conclusions. We demonstrate that ISD can be effectively detected, analysed, and even collected by space probes at 1 AU distance from the Sun.
Cluster counts: Calibration issue or new physics?
Authors: Sakr Ziad , Ilić Stéphane , Blanchard Alain , Bittar Jamal , Farah Wehbeh
Published: October 2018

In recent years, the amplitude of matter fluctuations inferred from low-redshift probes has been found to be generally lower than the value derived from cosmic microwave background (CMB) observations in the ΛCDM model. This tension has been exemplified by Sunyaev-Zel’dovich and X-ray cluster counts which, when using theirPlanckstandard cluster mass calibration, yield a value ofσ8, appreciably lower than estimations based on the latestPlanckCMB measurements. In this work we examine whether non-minimal neutrino masses can alleviate this tension substantially. We used the cluster X-ray temperature distribution function derived from a flux-limited sample of local X-ray clusters, combined withPlanckCMB measurements. These datasets were compared to ΛCDM predictions based on recent mass function, adapted to account for the effects of massive neutrinos. Treating the clusters mass calibration as a free parameter, we examined whether the data favours neutrino masses appreciably higher than the minimal 0.06 eV value. Using Markov chain Monte Carlo methods, we found no significant correlation between the mass calibration of clusters and the sum of neutrino masses, meaning that massive neutrinos do not noticeably alleviate the above-mentionedPlanckCMB–clusters tension. The addition of other datasets (baryon acoustic oscillations and Ly-α) reinforces those conclusions. As an alternative possible solution to the tension, we introduced a simple, phenomenological modification of gravity by letting the growth indexγvary as an additional free parameter. We find that the cluster mass calibration is robustly correlated with theγparameter, insensitively to the presence of massive neutrinos or/and additional data used. We conclude that the standardPlanckmass calibration of clusters, if consolidated, would represent evidence for new physics beyond ΛCDM with massive neutrinos.
Submillimeter polarization and variability of quasar PKS 1830–211
Authors: Marti-Vidal I. , Muller S.
Published: October 2018

Polarization from active galactic nuclei is interpreted as a signpost of the role of magnetic fields in the launch and collimation of their relativistic radio jets. Here, we report the detection of a clear polarization signal from ALMA observations of the gravitationally lensed quasar PKS 1830−211 at submillimeter wavelengths (Band 9, 650 GHz). Applying a differential-polarimetry technique to the two compact lensed images of the quasar, we estimate a fractional polarization of ∼5% for one lensed image, while the other appears nearly unpolarized, which implies that the polarization activity varies on a timescale of a few weeks. With additional ALMA Band 7 and 8 (between 300–500 GHz) concomitant data, we constrain a Faraday rotation of a few 105 rad m−2. We also observe flux-density variability of ≲10% within one hour in Band 9. This work illustrates that a differential analysis can extract high-accuracy information (flux-density ratio and polarimetry) free of calibration issues from resolved sources in the submillimeter domain.
System-reliability analysis of steel truss towers
Authors: Mochocki Wojciech , Obara Paulina , Radoń Urszula
Published: October 2018

Steel truss towers are important structures in civil engineering, used as, for example, antenna towers, architectural towers, transmission towers, chimney towers, light towers, viewing towers, or water towers. In the paper, the latter structural type is analysed. Three types of truss towers with different topology are discussed. The towers are designed according to the standards. Next, reliability analysis is performed and the influence of type of truss topology on reliability is analysed. Reliability analysis concerns formulation of the limit state, calculation of failure probability and determination of reliability index. In the paper, the system approach is proposed, definitely more complete than that obtained using approximation-simulation methods. In the case of structures analysed in the paper, the types of reliability models are determined. Identification of reliability models relies on studies on the transformation of the safe structural system into the geometrically variable system (mechanism). The investigations made it possible to determine the kinematically admissible failure mechanisms which contain minimal critical sets of elements. In order to identify the mechanism, spectral analysis of the linear stiffness matrix is used. In the case of the towers of concern, the formulas specifying the number of mechanisms for any number of repeating sections are determined.
On modelling of the buckling resistance of welded I-section columns
Authors: Szczerba Radosław , Gajewski Marcin , Giżejowski Marian
Published: October 2018

This paper analyzes the influence of geometrical and material imperfections on the buckling resistance of welded I-section columns subjected to axial compression through numerical and analytical models. The paper is divided into two parts. The first part recalls a FEM parametric study of members under compression taking into account different slenderness ratios, as well as different amplitudes of initial crookedness and different values of postwelding residual stresses. The formulation of analytical approach is the main issue of the second part of the paper. Analytical formulation of the buckling resistance is based on a statistical hypothesis of the minima value approach, called the Marchant-Rankine’s-Murzewski approach (M-R-M). Calibration of imperfection factors included in the analytical formulation is made using the results of FEM simulations performed in the first stage of research investigations.
Experimental study of mechanical properties of steel cables
Authors: Orzłowska Renata
Published: October 2018

Guyed masts are structures particularly sensitive to various types of nonlinarities. Static calculations of masts should be performed in accordance with EN 1993-3-1 using global elastic analysis. This is justified in the case of pre-stretched cables on mast guys, characterized by a constant value of the modulus of elasticity. In the case of non-stretched cables this approach is inappropriate, because permanent rope elongations caused by the applied load can significantly reduce the stiffness of the mast. The paper presents the preparation process of rope samples for experimental tests and preliminary results of tests aimed at determining the actual stress – strain relation of the rope and estimation a constant elastic modulus E of the cable after a few cycles of loading and unloading. The results of the obtained tests are introductory to further numerical analysis of guyed masts, including physical nonlinearity of guys.
Influence of sheet/purlin fasteners spacing on shear flexibility of the diaphragm
Authors: Korcz-Konkol Natalia , Urbańska-Galewska Elżbieta
Published: October 2018

The paper presents the influence of sheet/purlin fasteners location (in reference to trapezoidal profile cross section) on shear flexibility of the cladding acting as a diaphragm. Analytical procedures were presented and their limitations were discussed. Next, selected schemes of fasteners location, known from engineering practice, but not included in European codes and recommendations, were analysed numerically in order to observe the differences in shear stiffness of the panel. The cantilevered diaphragm as a part of the roof of a single storey building was chosen for the analysis. The analysis was carried out for the valley-fixed trapezoidal sheeting with wide pans. Corrugated sheets were built by two types of models: full 3D shell model and equivalent orthotropic 2D shell model. Flexibility of fasteners and connections was included in the calculations using equivalent beam finite elements. The results were discussed from the stressed-skin design point of view.
Influence of nonlinearities on the efficiency and accuracy of FEM calculations on the example of a steel build-up thin-walled column
Authors: Deniziak Patryk , Winkelmann Karol
Published: October 2018

Due to the increase of computing capabilities of standard processing units, it is possible to perform complex analyses, considering a number of nonlinearities, such as geometric, material and boundary (contact) even on personal computers. In the paper, the authors have analysed the efficiency and accuracy of standard PC’s FEM calculations performed in Abaqus CAE 2017 software on the example of a critical load assessment of a thin-walled steel column element with selected nonlinearities. A cross-section shape of a built-up column used by an international steel structures manufacturer was adopted. The analysis serves to check the behavior of their product. Several types of FEM analysis, strictly based on the EN standard regulations were performed. In turn, the relation of computational time to the adopted analysis type was obtained. Moreover, the produced load values in different types of independent calculation were compared and analysed. A possible future development in the field, based mainly on full-scale experimental tests, was also highlighted.
Comparison of theoretical deformation with real life model of a steel bridge span
Authors: Federowicz Karol
Published: October 2018

The article presents the selection process of a static system and optimization for steel bridge span. The issue was addressed as an entry to a BRICO 2017 contests in designing steel bridges. The proposed solutions were checked in terms of their bearing capacity, technological assembly and economics. General guidelines for geometry selection were described. The designed construction was produced and tested under load to determine the deflection in both vertical and horizontal plane. Furthermore, the article details the joints and technological issues met during the design process. Theoretical calculations and actual measurements on a real life model were compared. The process of structural design of civil engineering structures is a complicated, time consuming multilayered issue. The key to a good design lies in a compromise between esthetics, functionality, capacity exhaustion and technical possibilities.