bluuebunny/crossref_metadata_2025 huggingface dataset:
New Zealand glowworm (Arachnocampa luminosa) bioluminescence is produced by a firefly-like luciferase but an entirely new luciferin
Authors: Watkins Oliver C. , Sharpe Miriam L. , Perry Nigel B. , Krause Kurt L.
Published: February 2018

The New Zealand glowworm, Arachnocampa luminosa, is well-known for displays of blue-green bioluminescence, but details of its bioluminescent chemistry have been elusive. The glowworm is evolutionarily distant from other bioluminescent creatures studied in detail, including the firefly. We have isolated and characterised the molecular components of the glowworm luciferase-luciferin system using chromatography, mass spectrometry and 1H NMR spectroscopy. The purified luciferase enzyme is in the same protein family as firefly luciferase (31% sequence identity). However, the luciferin substrate of this enzyme is produced from xanthurenic acid and tyrosine, and is entirely different to that of the firefly and known luciferins of other glowing creatures. A candidate luciferin structure is proposed, which needs to be confirmed by chemical synthesis and bioluminescence assays. These findings show that luciferases can evolve independently from the same family of enzymes to produce light using structurally different luciferins.
Controlling striatal function via anterior frontal cortex stimulation
Authors: van Holstein Mieke , Froböse Monja I. , O’Shea Jacinta , Aarts Esther , Cools Roshan
Published: February 2018

Motivational, cognitive and action goals are processed by distinct, topographically organized, corticostriatal circuits. We aimed to test whether processing in the striatum is under causal control by cortical regions in the human brain by investigating the effects of offline transcranial magnetic stimulation (TMS) over distinct frontal regions associated with motivational, cognitive and action goal processing. Using a three-session counterbalanced within-subject crossover design, continuous theta burst stimulation was applied over the anterior prefrontal cortex (aPFC), dorsolateral prefrontal cortex, or premotor cortex, immediately after which participants (N = 27) performed a paradigm assessing reward anticipation (motivation), task (cognitive) switching, and response (action) switching. Using task-related functional magnetic resonance imaging (fMRI), we assessed the effects of stimulation on processing in distinct regions of the striatum. To account for non-specific effects, each session consisted of a baseline (no-TMS) and a stimulation (post-TMS) fMRI run. Stimulation of the aPFC tended to decrease reward-related processing in the caudate nucleus, while stimulation of the other sites was unsuccessful. A follow-up analysis revealed that aPFC stimulation also decreased processing in the putamen as a function of the interaction between all factors (reward, cognition and action), suggesting stimulation modulated the transfer of motivational information to cortico-striatal circuitry associated with action control.
Therapeutic effects of diclofenac, pregabalin, and duloxetine on disuse-induced chronic musculoskeletal pain in rats
Authors: Ohmichi Yusuke , Ohmichi Mika , Murai Nobuhito , Yasui Masaya , Takeshita Nobuaki , Oshibuchi Hidehiro , Naito Munekazu , Nakano Takashi , Sato Jun
Published: February 2018

The aim of this study was to clarify the mechanism of disuse-induced muscle hyperalgesia through the evaluation of the pharmacological behaviour of muscle hyperalgesia profiles in chronic post-cast pain (CPCP) rats with acute and chronic-phase mirror-image muscle hyperalgesia treated with diclofenac (NSAID), pregabalin (an inhibitor of Ca2+ channel α2δ), and duloxetine (SNRI). After 2 weeks of cast immobilization, the peak cross-sectional area and muscle wet weight of the ipsilateral soleus and gastrocnemius muscles decreased more significantly in CPCP rats than in untreated rats. Histological findings revealed disuse-induced muscle atrophy in CPCP rats. The blood biochemical parameters of CPCP rats in acute and chronic phases did not differ significantly from those of untreated rats. The diclofenac and pregabalin-treated groups exhibited no improvement in acute or chronic muscle hyperalgesia. In contrast, the duloxetine-treated group exhibited an improvement in acute muscle hyperalgesia, but showed no apparent effect on chronic muscle hyperalgesia on ipsilateral or contralateral sides. However, the chronic muscle hyperalgesia was reversed by intrathecal administration of DAMGO (a μ-opioid receptor agonist). The results suggest that chronic muscle hyperalgesia in CPCP rats did not result from an inflammatory mechanism, and there is only a low probability that it’s caused by a neuropathic mechanism.
Multiple Kernel Learning Model for Relating Structural and Functional Connectivity in the Brain
Authors: Surampudi Sriniwas Govinda , Naik Shruti , Surampudi Raju Bapi , Jirsa Viktor K. , Sharma Avinash , Roy Dipanjan
Published: February 2018

A challenging problem in cognitive neuroscience is to relate the structural connectivity (SC) to the functional connectivity (FC) to better understand how large-scale network dynamics underlying human cognition emerges from the relatively fixed SC architecture. Recent modeling attempts point to the possibility of a single diffusion kernel giving a good estimate of the FC. We highlight the shortcomings of the single-diffusion-kernel model (SDK) and propose a multi-scale diffusion scheme. Our multi-scale model is formulated as a reaction-diffusion system giving rise to spatio-temporal patterns on a fixed topology. We hypothesize the presence of inter-regional co-activations (latent parameters) that combine diffusion kernels at multiple scales to characterize how FC could arise from SC. We formulated a multiple kernel learning (MKL) scheme to estimate the latent parameters from training data. Our model is analytically tractable and complex enough to capture the details of the underlying biological phenomena. The parameters learned by the MKL model lead to highly accurate predictions of subject-specific FCs from test datasets at a rate of 71%, surpassing the performance of the existing linear and non-linear models. We provide an example of how these latent parameters could be used to characterize age-specific reorganization in the brain structure and function.
Filling the Gaps in the Kirromycin Biosynthesis: Deciphering the Role of Genes Involved in Ethylmalonyl-CoA Supply and Tailoring Reactions
Authors: Robertsen Helene L. , Musiol-Kroll Ewa M. , Ding Ling , Laiple Kristina J. , Hofeditz Torben , Wohlleben Wolfgang , Lee Sang Yup , Grond Stephanie , Weber Tilmann
Published: February 2018

Kirromycin is the main product of the soil-dwelling Streptomyces collinus Tü 365. The elucidation of the biosynthetic pathway revealed that the antibiotic is synthesised via a unique combination of trans-/cis-AT type I polyketide synthases and non-ribosomal peptide synthetases (PKS I/NRPS). This was the first example of an assembly line integrating the three biosynthetic principles in one pathway. However, information about other enzymes involved in kirromycin biosynthesis remained scarce. In this study, genes encoding tailoring enzymes KirM, KirHVI, KirOI, and KirOII, and the putative crotonyl-CoA reductase/carboxylase KirN were deleted, complemented, and the emerged products analysed by HPLC-HRMS and MS/MS. Derivatives were identified in mutants ΔkirM, ΔkirHVI, ΔkirOI, and ΔkirOII. The products of ΔkirOI, ΔkirOII, and kirHVI were subjected to 2D-NMR for structure elucidation. Our results enabled functional assignment of those enzymes, demonstrating their involvement in kirromycin tailoring. In the ΔkirN mutant, the production of kirromycin was significantly decreased. The obtained data enabled us to clarify the putative roles of the studied enzymes, ultimately allowing us to fill many of the missing gaps in the biosynthesis of the complex antibiotic. Furthermore, this collection of mutants can serve as a toolbox for generation of new kirromycins.
Evolving Bacterial Fitness with an Expanded Genetic Code
Authors: Tack Drew S. , Cole Austin C. , Shroff Raghav , Morrow Barrett R. , Ellington Andrew D.
Published: February 2018

Since the fixation of the genetic code, evolution has largely been confined to 20 proteinogenic amino acids. The development of orthogonal translation systems that allow for the codon-specific incorporation of noncanonical amino acids may provide a means to expand the code, but these translation systems cannot be simply superimposed on cells that have spent billions of years optimizing their genomes with the canonical code. We have therefore carried out directed evolution experiments with an orthogonal translation system that inserts 3-nitro-L-tyrosine across from amber codons, creating a 21 amino acid genetic code in which the amber stop codon ambiguously encodes either 3-nitro-L-tyrosine or stop. The 21 amino acid code is enforced through the inclusion of an addicted, essential gene, a beta-lactamase dependent upon 3-nitro-L-tyrosine incorporation. After 2000 generations of directed evolution, the fitness deficit of the original strain was largely repaired through mutations that limited the toxicity of the noncanonical. While the evolved lineages had not resolved the ambiguous coding of the amber codon, the improvements in fitness allowed new amber codons to populate protein coding sequences.
Cooling aerosols and changes in albedo counteract warming from CO2 and black carbon from forest bioenergy in Norway
Authors: Arvesen Anders , Cherubini Francesco , del Alamo Serrano Gonzalo , Astrup Rasmus , Becidan Michael , Belbo Helmer , Goile Franziska , Grytli Tuva , Guest Geoffrey , Lausselet Carine , Rørstad Per Kristian , Rydså Line , Seljeskog Morten , Skreiberg Øyvind , Vezhapparambu Sajith , Strømman Anders Hammer
Published: February 2018

Climate impacts of forest bioenergy result from a multitude of warming and cooling effects and vary by location and technology. While past bioenergy studies have analysed a limited number of climate-altering pollutants and activities, no studies have jointly addressed supply chain greenhouse gas emissions, biogenic CO2 fluxes, aerosols and albedo changes at high spatial and process detail. Here, we present a national-level climate impact analysis of stationary bioenergy systems in Norway based on wood-burning stoves and wood biomass-based district heating. We find that cooling aerosols and albedo offset 60–70% of total warming, leaving a net warming of 340 or 69 kg CO2e MWh−1 for stoves or district heating, respectively. Large variations are observed over locations for albedo, and over technology alternatives for aerosols. By demonstrating both notable magnitudes and complexities of different climate warming and cooling effects of forest bioenergy in Norway, our study emphasizes the need to consider multiple forcing agents in climate impact analysis of forest bioenergy.
Assessment of soil heavy metals for eco-environment and human health in a rapidly urbanization area of the upper Yangtze Basin
Authors: Jia Zhongmin , Li Siyue , Wang Li
Published: February 2018

Soil pollution with heavy metals (HMs) has been attracting more and more interests, however, assessment of eco-environmental and human risks particularly in a rapidly urbanization area (the upper Yangtze) remains limited. Multiple modern indices were firstly performed for complete risk assessment of eco-environment and human health based on a high-spatial-resolution sampling. Averages of HMs were far below grade II threshold level of the Chinese Environmental Quality standards for soils, whereas Cd, As and Hg considerably exceeded the local background values. EF suggested overall moderate enrichments of Cd and Se, resulting in soils uncontaminated to moderately contaminated with them. Potential ecological risk index showed significant differences among Counties that were characterized by moderate risk. However, several sites were moderately to heavily contaminated with As, Cd and Hg by Igeo, resulting in that these sites were categorized as “considerable risk”, or “high risk”. Moreover, children were more susceptible to the potential health risk irrespective of the carcinogenic or non – carcinogenic risk. There were no significant carcinogenic and non – carcinogenic risks for adults, children however showed significant non – carcinogenic effect. Our first assessment provided important information for policy making to reduce the potential effects of soil contamination on human and eco-environment.
Common Deregulation of Seven Biological Processes by MicroRNAs in Gastrointestinal Cancers
Authors: Zhang Lin , Zhang Yuchen , Wong Sunny H. , Law Priscilla T. Y. , Zhao Shan , Yu Jun , Chan Matthew T. V. , Wu William K. K.
Published: February 2018

MicroRNAs are frequently dysregulated in human neoplasms, including gastrointestinal cancers. Nevertheless, the global influence of microRNA dysregulation on cellular signaling is still unknown. Here we sought to elucidate cellular signaling dysregulation by microRNAs in gastrointestinal cancers at the systems biology level followed by experimental validation. Signature dysregulated microRNAs in gastric, colorectal and liver cancers were defined based on our previous studies. Targets of signature dysregulated miRNAs were predicted using multiple computer algorithms followed by gene enrichment analysis to identify biological processes perturbed by dysregulated microRNAs. Effects of microRNAs on endocytosis were measured by epidermal growth factor (EGF) internalization assay. Our analysis revealed that, aside from well-established cancer-related signaling pathways, several novel pathways, including axon guidance, neurotrophin/nerve growth factor signaling, and endocytosis, were found to be involved in the pathogenesis of gastrointestinal cancers. The regulation of EGF receptor (EGFR) endocytosis by two predicted miRNAs, namely miR-17 and miR-145, was confirmed experimentally. Functionally, miR-145, which blocked EGFR endocytosis, prolonged EGFR membrane signaling and altered responsiveness of colon cancer cells to EGFR-targeting drugs. In conclusion, our analysis depicts a comprehensive picture of cellular signaling dysregulation, including endocytosis, by microRNAs in gastrointestinal cancers.
In silico guided reconstruction and analysis of ICAM-1-binding var genes from Plasmodium falciparum
Authors: Carrington Eilidh , Otto Thomas D. , Szestak Tadge , Lennartz Frank , Higgins Matt K. , Newbold Chris I. , Craig Alister G.
Published: February 2018

The Plasmodium falciparum variant surface antigen PfEMP1 expressed on the surface of infected erythrocytes is thought to play a major role in the pathology of severe malaria. As the sequence pool of the var genes encoding PfEMP1 expands there are opportunities, despite the high degree of sequence diversity demonstrated by this gene family, to reconstruct full-length var genes from small sequence tags generated from patient isolates. To test whether this is possible we have used a set of recently laboratory adapted ICAM-1-binding parasite isolates to generate sequence tags and, from these, to identify the full-length PfEMP1 being expressed by them. In a subset of the strains available we were able to produce validated, full-length var gene sequences and use these to conduct biophysical analyses of the ICAM-1 binding regions.
Cocaine-induced locomotor sensitization associates with slow oscillatory firing of neurons in the ventral tegmental area
Authors: Liu Chang-Liang , Wang Ya-Kun , Jin Guo-Zhang , Shi Wei-Xing , Gao Ming
Published: February 2018

The initiation of psychostimulant sensitization depends on the mesocorticolimbic dopamine (DA) system. Although many cellular adaptations has been reported to be associated with this addictive behavior, the overall influence of these adaptations on the network regulation of DA neurons has not been established. Here, we profile a network-driven slow oscillation (SO) in the firing activity of ventral tegmental area (VTA) putative DA and non-DA neurons and their correlation with locomotor sensitization induced by repeated administration of cocaine. One day after the last cocaine injection, the power of SO (Pso) significantly increased both in DA and non-DA neurons. Interestingly, the Pso in DA neurons was positively correlated, while Pso in non-DA neurons was negatively correlated with the level of locomotor sensitization. On the other hand, the firing rates of DA and non-DA neurons were both elevated, but none exhibited any correlation with the level of sensitization. Fourteen days after the last injection, the Pso of DA neurons dissipated but still positively correlated with the level of sensitization. In contrast, the Pso in non-DA neurons lost correlation with locomotor sensitization. These results suggest that cocaine-induced locomotor sensitization is associated with long-term network adaptation in DA system and that DA and non-DA neurons may corporately facilitate/hamper the initiation of locomotor sensitization.
Understanding the functional role of genistein in the bone differentiation in mouse osteoblastic cell line MC3T3-E1 by RNA-seq analysis
Authors: Kim Myungsuk , Lim Jisun , Lee Jung-Hee , Lee Kyung-Mi , Kim Suji , Park Kye Won , Nho Chu Won , Cho Yoon Shin
Published: February 2018

Genistein, a phyto-estrogen, can potentially replace endogenous estrogens in postmenopausal women, but the underlying molecular mechanisms remain incompletely understood. To obtain insight into the effect of genistein on bone differentiation, RNA sequencing (RNA-seq) analysis was used to detect differentially expressed genes (DEGs) in genistein-treated vs. untreated MC3T3-E1 mouse osteoblastic cells. Osteoblastic cell differentiation was monitored by measuring osteoblast differentiation factors (ALP production, bone mineralization, and expression of osteoblast differentiation markers). From RNA-seq analysis, a total of 132 DEGs (including 52 up-regulated and 80 down-regulated genes) were identified in genistein-treated cells (FDR q-value < 0.05 and fold change > 1.5). KEGG pathway and Gene Ontology (GO) enrichment analyses were performed to estimate the biological functions of DEGs and demonstrated that these DEGs were highly enriched in functions related to chemotactic cytokines. The functional relevance of DEGs to genistein-induced osteoblastic cell differentiation was further evaluated by siRNA-mediated knockdown in MC3T3-E1 cells. These siRNA knockdown experiments (of the DEGs validated by real-time qPCR) demonstrated that two up-regulated genes (Ereg and Efcab2) enhance osteoblastic cell differentiation, while three down-regulated genes (Hrc, Gli, and Ifitm5) suppress the differentiation. These results imply their major functional roles in bone differentiation regulated by genistein.
Decontamination of Petroleum-Contaminated Soils Using The Electrochemical Technique: Remediation Degree and Energy Consumption
Authors: Streche Constantin , Cocârţă Diana Mariana , Istrate Irina-Aura , Badea Adrian Alexandru
Published: February 2018

Currently, there are different remediation technologies for contaminated soils, but the selection of the best technology must be not only the treatment efficiency but also the energy consumption (costs) during its application. This paper is focused on assessing energy consumption related to the electrochemical treatment of polluted soil with petroleum hydrocarbons. In the framework of a research project, two types of experiments were conducted using soil that was artificially contaminated with diesel fuel at the same level of contamination. The experimental conditions considered for each experiment were: different amounts of contaminated soils (6 kg and 18 kg, respectively), the same current intensity level (0.25A and 0.5A), three different contamination degrees (1%, 2.5% and 5%) and the same time for application of the electrochemical treatment. The remediation degree concerning the removal of petroleum hydrocarbons from soil increased over time by approximately 20% over 7 days. With regard to energy consumption, the results revealed that with an increase in the quantity of treated soil of approximately three times, the specific energy consumption decreased from 2.94 kWh/kg treated soil to 1.64 kWh/kg treated soil.
Investigation on the role of surfactants in bubble-algae interaction in flotation harvesting of Chlorella vulgaris
Authors: Shen Zhou , Li Yanpeng , Wen Hao , Ren Xiangying , Liu Jun , Yang Liwei
Published: February 2018

In this work, a fundamental study was carried out on the role of surfactants in bubble-algae interaction to improve the understanding of how surfactants influence the flotation performance. Flotation tests for harvesting Chlorella vulgaris were first conducted using two surfactants, hexadecyltrimethyl ammonium bromide (C16TAB) and tea saponin. The effect of surfactants on harvesting efficiency was found to depend on their type and concentration. The present results also indicated that C16TAB exhibited higher harvesting efficiency than tea saponin. The adsorption experiments of surfactants onto C. vulgaris and the characterization measurements of algae surface were then carried out to reveal underlying interaction mechanisms between surfactants and algae in air flotation process. The results confirmed the adsorption process of surfactants onto C. vulgaris was feasible, spontaneous and endothermic. Subsequently, two mechanism models were proposed to qualitatively establish the interaction relationship among algae, surfactants and bubbles in the flotation. According to two models, C16TAB could neutralize the algal potential, while tea saponin converted algal surface from hydrophilic into hydrophobic. Overall, two surfactants used here could facilitate attachment of C. vulgaris onto bubbles, making the algae easier to be harvested, thereby increasing the flotation recovery.
On mechanical behaviors of few-layer black phosphorus
Authors: Li Lili , Yang Jie
Published: February 2018

This paper investigates the mechanical behaviors of few-layer black phosphorus (FLBP) by using molecular dynamics simulations. Results show that both tensile and compressive behaviors are strongly anisotropic in the armchair and zigzag directions due to the unidirectional puckers in each atomic layer, and that the compressive behavior is dependent on the number of atomic layers. In particular, the compressive and buckling strengths of FLBP can be significantly enhanced by stacking more atomic layers together, while this has little influence on both Young’s modulus and tensile strength. It is interesting to found that increasing the number of atomic layers in FLBP or the dimension ratio can lead to a drastically reduced flexibility in armchair direction, showing that both compressive and buckling strengths become higher than those in zigzag direction. It is also demonstrated that the reorientation of FLBP’s atomic configuration occurs under certain conditions. The mechanism of deformation underlying the mechanical behaviors of FLBP is also discussed, suggesting that changing the number of atomic layers is an effective way to engineer two-dimensional materials for desired material properties.
Nano-Architecture of nitrogen-doped graphene films synthesized from a solid CN source
Authors: Maddi Chiranjeevi , Bourquard Florent , Barnier Vincent , Avila José , Asensio Maria-Carmen , Tite Teddy , Donnet Christophe , Garrelie Florence
Published: February 2018

New synthesis routes to tailor graphene properties by controlling the concentration and chemical configuration of dopants show great promise. Herein we report the direct reproducible synthesis of 2-3% nitrogen-doped ‘few-layer’ graphene from a solid state nitrogen carbide a-C:N source synthesized by femtosecond pulsed laser ablation. Analytical investigations, including synchrotron facilities, made it possible to identify the configuration and chemistry of the nitrogen-doped graphene films. Auger mapping successfully quantified the 2D distribution of the number of graphene layers over the surface, and hence offers a new original way to probe the architecture of graphene sheets. The films mainly consist in a Bernal ABA stacking three-layer architecture, with a layer number distribution ranging from 2 to 6. Nitrogen doping affects the charge carrier distribution but has no significant effects on the number of lattice defects or disorders, compared to undoped graphene synthetized in similar conditions. Pyridinic, quaternary and pyrrolic nitrogen are the dominant chemical configurations, pyridinic N being preponderant at the scale of the film architecture. This work opens highly promising perspectives for the development of self-organized nitrogen-doped graphene materials, as synthetized from solid carbon nitride, with various functionalities, and for the characterization of 2D materials using a significant new methodology.
Genomics of a pediatric ovarian fibrosarcoma. Association with the DICER1 syndrome
Authors: Melendez-Zajgla Jorge , Mercado-Celis Gabriela E. , Gaytan-Cervantes Javier , Torres Amada , Gabiño Nayeli Belem , Zapata-Tarres Martha , Juarez-Villegas Luis Enrique , Lezama Pablo , Maldonado Vilma , Ruiz-Monroy Karen , Mendoza-Caamal Elvia
Published: February 2018

Ovarian fibrosarcomas are extremely rare tumors with little genomic information available to date. In the present report we present the tumoral exome and transcriptome and the germinal exome of an ovarian fibrosarcoma from a 9-years old child. We found a paucity of mutations (0.77/Mb) and CNV alterations. Of these, the most relevant were a point mutation in the metal-binding site of the microRNA-processing DICER1 enzyme and a frame-shift alteration in the tumor suppressor gene NF1. We validated a germinal truncating mutation in DICER1, which was consistent with a DICER1 Syndrome diagnosis, providing the first example of an ovarian fibrosarcoma as the presenting neoplasia in this syndrome. Network and enrichment analyses showed that both a mesenchymal signature and a Hedgehog cascade could be driving the progression of this tumor. We were also able to find a global lincRNA deregulation, as the number of lincRNAs transcripts expressed in the tumor was decreased, with a concomitant upregulation of previously described non-coding transcripts associated with cancer, such as MALAT1, MIR181A1HG, CASC1, XIST and FENDRR. DICER1 Syndrome should be considered as a possible diagnosis in children ovarian fibrosarcoma. The role of lncRNAs in neoplasias associated with DICER1 alterations need to be studied in more detail.
A fuzzy feature fusion method for auto-segmentation of gliomas with multi-modality diffusion and perfusion magnetic resonance images in radiotherapy
Authors: Guo Lu , Wang Ping , Sun Ranran , Yang Chengwen , Zhang Ning , Guo Yu , Feng Yuanming
Published: February 2018

The diffusion and perfusion magnetic resonance (MR) images can provide functional information about tumour and enable more sensitive detection of the tumour extent. We aimed to develop a fuzzy feature fusion method for auto-segmentation of gliomas in radiotherapy planning using multi-parametric functional MR images including apparent diffusion coefficient (ADC), fractional anisotropy (FA) and relative cerebral blood volume (rCBV). For each functional modality, one histogram-based fuzzy model was created to transform image volume into a fuzzy feature space. Based on the fuzzy fusion result of the three fuzzy feature spaces, regions with high possibility belonging to tumour were generated automatically. The auto-segmentations of tumour in structural MR images were added in final auto-segmented gross tumour volume (GTV). For evaluation, one radiation oncologist delineated GTVs for nine patients with all modalities. Comparisons between manually delineated and auto-segmented GTVs showed that, the mean volume difference was 8.69% (±5.62%); the mean Dice’s similarity coefficient (DSC) was 0.88 (±0.02); the mean sensitivity and specificity of auto-segmentation was 0.87 (±0.04) and 0.98 (±0.01) respectively. High accuracy and efficiency can be achieved with the new method, which shows potential of utilizing functional multi-parametric MR images for target definition in precision radiation treatment planning for patients with gliomas.
Ultrafast evolution of electric fields from high-intensity laser-matter interactions
Authors: Pompili R. , Anania M. P. , Bisesto F. , Botton M. , Chiadroni E. , Cianchi A. , Curcio A. , Ferrario M. , Galletti M. , Henis Z. , Petrarca M. , Schleifer E. , Zigler A.
Published: February 2018

The interaction of high-power ultra-short lasers with materials offers fascinating wealth of transient phenomena which are in the core of novel scientific research. Deciphering its evolution is a complicated task that strongly depends on the details of the early phase of the interaction, which acts as complex initial conditions. The entire process, moreover, is difficult to probe since it develops close to target on the sub-picosecond timescale and ends after some picoseconds. Here we present experimental results related to the fields and charges generated by the interaction of an ultra-short high-intensity laser with metallic targets. The temporal evolution of the interaction is probed with a novel femtosecond resolution diagnostics that enables the differentiation of the contribution by the high-energy forerunner electrons and the radiated electromagnetic pulses generated by the currents of the remaining charges on the target surface. Our results provide a snapshot of huge pulses, up to 0.6 teravolt per meter, emitted with multi-megaelectronvolt electron bunches with sub-picosecond duration and are able to explore the processes involved in laser-matter interactions at the femtosecond timescale.
Compilation of climate data from heterogeneous networks across the Hawaiian Islands
Authors: Longman Ryan J. , Giambelluca Thomas W. , Nullet Michael A. , Frazier Abby G. , Kodama Kevin , Crausbay Shelley D. , Krushelnycky Paul D. , Cordell Susan , Clark Martyn P. , Newman Andy J. , Arnold Jeffrey R.
Published: February 2018

Long-term, accurate observations of atmospheric phenomena are essential for a myriad of applications, including historic and future climate assessments, resource management, and infrastructure planning. In Hawai‘i, climate data are available from individual researchers, local, State, and Federal agencies, and from large electronic repositories such as the National Centers for Environmental Information (NCEI). Researchers attempting to make use of available data are faced with a series of challenges that include: (1) identifying potential data sources; (2) acquiring data; (3) establishing data quality assurance and quality control (QA/QC) protocols; and (4) implementing robust gap filling techniques. This paper addresses these challenges by providing: (1) a summary of the available climate data in Hawai‘i including a detailed description of the various meteorological observation networks and data accessibility, and (2) a quality controlled meteorological dataset across the Hawaiian Islands for the 25-year period 1990-2014. The dataset draws on observations from 471 climate stations and includes rainfall, maximum and minimum surface air temperature, relative humidity, wind speed, downward shortwave and longwave radiation data.
Low-temperature CO oxidation over integrated penthorum chinense-like MnCo2O4 arrays anchored on three-dimensional Ni foam with enhanced moisture resistance
Authors: Mo Shengpeng , Li Shuangde , Xiao Hailin , He Hui , Xue Yudong , Zhang Mingyuan , Ren Quanming , Chen Bingxu , Chen Yunfa , Ye Daiqi
Published: February 2018

Advanced integrated nanoarray (NA) catalysts have been designed by growing metal-doped Co3O4 arrays on nickel foam with robust adhesion.
Polyphenols-rich extract from Pleurotus eryngii with growth inhibitory of HCT116 colon cancer cells and anti-inflammatory function in RAW264.7 cells
Authors: Hu Qiuhui , Yuan Biao , Xiao Hang , Zhao Liyan , Wu Xian , Rakariyatham Kanyasiri , Zhong Lei , Han Yanhui , Muinde Kimatu Benard , Yang Wenjian
Published: February 2018

Edible mushrooms are rich sources of bioactive components.
Mechanical and tribological performance of a hybrid MMC coating deposited on Al–17Si piston alloy by laser composite surfacing technique
Authors: Quazi M. M. , Ishak M. , Arslan A. , Fazal M. A. , Yusof Farazila , Sazzad B. S. , Nasir Bashir M. , Jamshaid M.
Published: February 2018

The addition of graphite as solid lubricant has significantly reduced the friction coefficient and wear of a Ni–WC composite coating.
Highly efficient pollutant removal of graphitic carbon nitride by the synergistic effect of adsorption and photocatalytic degradation
Authors: Song Xueping , Yang Qin , Yin Mengyun , Tang Dan , Zhou Limei
Published: February 2018

A novel g-C3N4 with strong adsorption capability and efficient photocatalysis activity was prepared by heating urea through a facile method.
Factors affecting the structure of lyotropic liquid crystals and the correlation between structure and drug diffusion
Authors: Huang Yiming , Gui Shuangying
Published: February 2018

Factors such as amphiphilic molecules , water content, temperature, pressure, light and magnetic field on the structures of LLCs.
Ti surface doping of LiNi0.5Mn1.5O4−δ positive electrodes for lithium ion batteries
Authors: Ulu Okudur F. , D'Haen J. , Vranken T. , De Sloovere D. , Verheijen M. , Karakulina O. M. , Abakumov A. M. , Hadermann J. , Van Bael M. K. , Hardy A.
Published: February 2018

LiNi0.5Mn1.5O4−δ surface is doped with Ti ion maintaining the spinel structure at 500 °C, higher annealing temperatures cause Ti diffusion from surface towards the core.
Coaxial heterojunction carbon nanofibers with charge transport and electrocatalytic reduction phases for high performance dye-sensitized solar cells
Authors: Wang Yuan-Hua , Fang Hai-Qiu , Dong Qiang , Si Duan-Hui , Song Xue-Dan , Yu Chang , Qiu Jie-Shan
Published: February 2018

Coaxial CNFs featured high conductivity derived from HP, and high N content and defective sites derived from PAN.
Copper-doped lanthanum manganite La0.65Ce0.05Sr0.3Mn1−xCuxO3 influence on structural, magnetic and magnetocaloric effects
Authors: Chebaane M. , Bellouz R. , Oumezzine Ma. , Hlil E. K. , Fouzri A.
Published: February 2018

Bulk nanocrystalline samples of La0.65Ce0.05Sr0.3Mn1−xCuxO3 (0 ≤ x ≤ 0.15) manganites are prepared by the sol–gel based Pechini method.
Efficient and reusable SBA-15-immobilized Brønsted acidic ionic liquid for the ketalization of cyclohexanone with glycol
Authors: Li Ruiyun , Song Heyuan , Wang Guoqin , Chen Jing
Published: February 2018

Molecular sieve SBA-15 immobilized Brønsted acidic ionic liquid: an efficient and recyclable catalyst for the ketalization of cyclohexanone with glycol.
Structural, electronic, vibration and elastic properties of the layered AgInP2S6semiconducting crystal – DFT approach
Authors: Babuka T. , Glukhov K. , Vysochanskii Y. , Makowska-Janusik M.
Published: February 2018

First principles calculations of the structural, electronic and vibrational properties of the AgInP2S6crystal were reported. Data were analyzed within the framework of the group theory approach. Results were compared to the experimental data.
Thermochemistry of gas-phase and surface speciesviaLASSO-assisted subgraph selection
Authors: Gu Geun Ho , Plechac Petr , Vlachos Dionisios G.
Published: February 2018

Graph theory-based regression techniques, such as group additivity, have widely been implemented for fast estimation of thermochemistry of large molecules.
Achieving foaming control smartly: pre-solubilized flavor oil serves as an in situ homogeneous defoamer
Authors: Qi Na , Sun Haoyang , Zhao Hui , Li Ying
Published: February 2018

The smart foaming control performance of a swollen micelle system and the mechanism at the microscopic level were studied.
In situ TEM observation of rebonding on fractured silicon carbide
Authors: Zhang Zhenyu , Cui Junfeng , Wang Bo , Jiang Haiyue , Chen Guoxin , Yu Jinhong , Lin Chengte , Tang Chun , Hartmaier Alexander , Zhang Junjie , Luo Jun , Rosenkranz Andreas , Jiang Nan , Guo Dongming
Published: February 2018

A novel approach is developed using an eyebrow hair to pick up and transfer nanowires (NWs), in order to obtain in situ transmission electron microscope (TEM) images of the rebonding and self-matching of SFs at atomic resolution.
A dual-responsive cross-linked supramolecular polymer network gel: hierarchical supramolecular self-assembly driven by pillararene-based molecular recognition and metal–ligand interactions
Authors: Shao Li , Yang Jie , Hua Bin
Published: February 2018

A novel 2,2′-bipyridine-bridged pillar[5]arene dimer was synthesized and further applied for constructing linear supramolecular polymers and supramolecular polymer network gels.
Fluorescence control of chitin and chitosan fabricatedviasurface functionalization using direct oxidative polymerization
Authors: Phung Hai Thien An , Sugimoto Ryuichi
Published: February 2018

The copolymer of 3-hexylthiophene (3HT) and fluorene (F) was directly grafted onto chitin and chitosan using FeCl3as an oxidant.
Simultaneous recovery of high-purity copper and polyvinyl chloride from thin electric cables by plasticizer extraction and ball milling
Authors: Xu Jing , Tazawa Naoki , Kumagai Shogo , Kameda Tomohito , Saito Yuko , Yoshioka Toshiaki
Published: February 2018

Herein, we introduce a combination of plasticizer extraction from polyvinyl chloride (PVC) and ball milling for the simultaneous, effective recovery of PVC and copper (Cu) from thin electric cables.
Blockade of glutamate receptor ameliorates lipopolysaccharide-induced sepsis through regulation of neuropeptides
Authors: Zhe Zhai , Hongyuan Bi , Wenjuan Qiao , Peng Wang , Xiaowei Liu , Yan Gao
Published: February 2018

Glutamate receptors (N-methyl-d-aspartate receptor (NMDAR)) are expressed mainly in the central nervous system (CNS), but several potentially important exceptions are worth mentioning. Recently, NMDAR, a glutamate receptor, has been reported to be found in the lungs. NMDAR is activated in acute lung injury (ALI). Here, the present experiment was designed to examine whether NMDAR blockade (MK-801) ameliorates ALI through affecting neuropeptides in LPS-induced sepsis animal models. Male Kunming mice were divided into control group, LPS group, control + MK-801 group, and LPS + MK-801 group. Bronchoalveolar lavage fluid (BALF) was collected and evaluated. The lung histological pathology was assayed by immunocytochemistry staining. Western blot was used to measure PGP9.5, substance P (SP), and vasoactive intestinal polypeptide (VIP). Results showed that LPS-induced mice animal models were ameliorated by co-treatment with the MK-801, an uncompetitive NMDAR antagonist. Moreover, the protective effects of MK-801 attributed to the increased secretion of VIP and decreased secretion of SP. The results of the present study indicated that the blockade of NMDAR may represent a promising therapeutic strategy for the treatment of sepsis-associated ALI through regulation of neuropeptides.
Urinary levels of sirtuin-1 associated with disease activity in lupus nephritis
Authors: Olivares Dolores , Perez-Hernandez Javier , Forner Maria J. , Perez-Soriano Cristina , Tormos Maria C. , Saez Guillermo T. , Chaves Felipe J. , Redon Josep , Cortes Raquel
Published: February 2018

Identifying new markers of disease flares in lupus nephritis (LN) that facilitate patient stratification and prognosis is important. Therefore, the aim of the present study was to analyze whether urinary SIRT1 expression was altered in LN and whether SIRT1 values in urine could be valuable biomarker of disease activity. In a cohort study, urinary pellets from 40 patients diagnosed with systemic lupus erythematosus (SLE) were analyzed. Clinical measures of lupus activity were assessed. The expression of SIRT1 was quantified by quantitative PCR (qRT-PCR) and immunoblot, then compared between patients with active lupus nephritis, in remission and healthy controls. Association with lupus activity and renal histological features was also analyzed. A significant increase in SIRT1 mRNA levels in patients with active LN was observed compared with those in remission (P=0.02) or healthy controls (P=0.009). In addition, SIRT-1 protein levels were also augmented in LN group than remission (P=0.029) and controls (P=0.001). A strong association was found between SIRT1 expression with anti-dsDNA in SLE and in patients with LN. In addition, histological features in LN biopsies were related with SIRT1, increasing its expression in proliferative forms. Finally, SIRT1 expression values showed a strong discriminatory power of renal injury in SLE. Our study demonstrated an altered urinary expression of SIRT1 and a strong association with disease activity in LN patients, being a valuable marker of renal injury. These results showed the role of the SIRT1 pathway in the SLE pathogenesis.
Robust resource allocation for heterogeneous wireless network: a worst‐case optimisation
Authors: Xu Yongjun , Hu Yuan , Li Guoquan , Zhang Haibo
Published: February 2018

With the development of fifth generation wireless communication technology, how to improve system capacity and spectrum efficiency is a crucial problem in resource sharing of heterogeneous networks (HetNets). Most of existing resource allocation (RA) schemes in HetNets focus on perfect channel state information, however, exact channel information is difficult to obtain under link delay and stochastic channel condition. In order to resolve the RA issues under channel uncertainties, a robust RA algorithm is proposed to maximise the sum data rate of microcell users where the users are subjected to the individual transmission power constraint and the cross‐tier interference constraint of macrocell users. The multiuser RA problem in HetNets is formulated under the consideration of bounded channel gain uncertainties where both the cross‐tier channel and intra‐tier channel are simultaneously considered. The non‐linear optimisation problem is converted into a geometric programming problem that is solved by using Lagrange dual methods in a distributed way. Simulation results show that the proposed algorithm can well restrain the effect of channel uncertainty and achieve a good robustness.
Adaptive multi‐dimensional Taylor network tracking control for SISO uncertain stochastic non‐linear systems
Authors: Han Yu‐Qun , Yan Hong‐Sen
Published: February 2018

In this study, the problem of adaptive multi‐dimensional Taylor network (MTN) control for single‐input single‐output (SISO) uncertain stochastic non‐linear systems is investigated. How to minimise the influence of randomness and uncertain non‐linearity for less complex computation, and how to improve the real‐time performance of the controller are of great significance. To this end, a control approach based on MTN is proposed for tracking control of stochastic non‐linear systems. MTNs are used to approximate the non‐linearities, and the backstepping technique is employed to construct the MTN controller (MTNC). MTNC involves only addition and multiplication, featuring desirable simplicity and real‐time performance. Stability of the system is guaranteed via Lyapunov approach, and it is proved that the proposed controller can guarantee that all signals of the closed‐loop system remain bounded in probability, and the tracking error converges to an arbitrarily small neighbourhood around the origin. Finally, a numerical example is given to illustrate the effectiveness of the proposed design approach, and simulation results demonstrate that the method presented in this study has good real‐time performance and control quality.
Suboptimal adaptive control of dynamic systems with state constraints based on Barrier Lyapunov functions
Authors: Salgado Iván , Mera Manuel , Chairez Isaac
Published: February 2018

This study designed a suboptimal output control strategy to characterise an attractive and invariant set for the state trajectories of perturbed linear systems with noisy measurements and state constraints. The state constraints were defined by a given polytope formed of by n ‐dimensional vectors. An adaptive linear controller enforced the existence of an attractive and invariant set (centred at the origin) for the trajectories of the perturbed system. A barrier Lyapunov function (BLF) and the attractive ellipsoid method (AEM) derived the adjustment law of the adaptive gain. The controller design used the linear matrix inequality technique to solve two optimisation problems. The first solution provided a maximal set where the initial conditions must belong without violating the state constraints. The second optimisation solution characterised the invariant minimal attractive set for the system trajectories. An academic example verified how the proposed adaptive control generated the system trajectories that converged to the minimal attractive ellipsoid while keeping them inside the polytope defining the state constraints. The simulation script showed the advantages of the adaptive BLF controller (ABLC) against classical AEM controller. A second numerical example considered a direct current motor showing the advantages of the ABLC against the sliding mode technique.
Primary frequency control of DFIG‐WTs using bang‐bang phase angle controller
Authors: Liu Yang , Jiang Lin , Smith Jeremy S. , Wu Q. H.
Published: February 2018

A bang‐bang phase angle controller (BPAC) was proposed in this study for the primary frequency control of doubly‐fed induction generator‐based wind turbines (DFIG‐WTs). Dynamics of the internal voltage of a synchronous generator (SG) and that of a DFIG‐WT were investigated in frequency deviation events. A BPAC was designed to regulate the phase angle obtained with a phase‐locked loop directly, which enables the rapid active power control of the DFIG‐WT. The BPAC signal is fed into the active power regulation loop of the pitch angle controller, which is expected to help rotor speed recovery and prevent secondary frequency drop. The small‐signal analysis was carried out for the closed‐loop system, composed of the DFIG‐WT and the external SG‐based power system, to verify the stability of the overall system. Simulation studies were undertaken on a wind power penetrated multi‐machine power system, through which the primary frequency control performance of the BPAC was verified.
Adaptive active contours based on variable kernel with constant initialisation
Authors: Munir Asad , Soomro Shafiullah , Lee Chang Ha , Choi Kwang Nam
Published: February 2018

In this paper, a novel method of active contours based on the formulation of partial differential equation (PDE) is proposed for image segmentation. The evolution equation incorporates a force term that pushes the contour towards object boundary, a regularisation term which takes into account the smoothness of the level set function and an edge term which helps to stop the contour at required boundaries. The proposed method integrates an image convolved by a variable kernel into an energy formulation, where the width of the kernel varies in each iteration. Therefore, it takes local region information when the width of the kernel is small while for the larger width of the kernel, the proposed method considers global region information across the regions. Due to the use of both local and global image information, the method easily detects objects in the complex background and also segments the objects where intensity changes within the object. Moreover, the proposed method totally eliminates the need of the contour initialisation by using constant initialisation scheme. Experimental results on real and medical images prove the robustness of the proposed method. Finally, the authors validate their method on PH2 database for skin lesion segmentation.