bluuebunny/crossref_metadata_2025 huggingface dataset:
Multi-drug resistant Klebsiella pneumoniae strains circulating in hospital setting: whole-genome sequencing and Bayesian phylogenetic analysis for outbreak investigations
Authors: Cella Eleonora , Ciccozzi Massimo , Lo Presti Alessandra , Fogolari Marta , Azarian Taj , Prosperi Mattia , Salemi Marco , Equestre Michele , Antonelli Francesca , Conti Alessia , Cesaris Marina De , Spoto Silvia , Incalzi Raffaele Antonelli , Coppola Roberto , Dicuonzo Giordano , Angeletti Silvia
Published: June 2017

Carbapenems resistantEnterobacteriaceaeinfections are increasing worldwide representing an emerging public health problem. The application of phylogenetic and phylodynamic analyses to bacterial whole genome sequencing (WGS) data have become essential in the epidemiological surveillance of multi-drug resistant nosocomial pathogens. Between January 2012 and February 2013, twenty-one multi-drug resistantK.pneumoniaestrains, were collected from patients hospitalized among different wards of the University Hospital Campus Bio-Medico. Epidemiological contact tracing of patients and Bayesian phylogenetic analysis of bacterial WGS data were used to investigate the evolution and spatial dispersion ofK.pneumoniaein support of hospital infection control. The epidemic curve of incidentK.pneumoniaecases showed a bimodal distribution of cases with two peaks separated by 46 days between November 2012 and January 2013. The time-scaled phylogeny suggested thatK.pneumoniaestrains isolated during the study period may have been introduced into the hospital setting as early as 2007. Moreover, the phylogeny showed two different epidemic introductions in 2008 and 2009. Bayesian genomic epidemiology is a powerful tool that promises to improve the surveillance and control of multi-drug resistant pathogens in an effort to develop effective infection prevention in healthcare settings or constant strains reintroduction.
Skin sloughing in susceptible and resistant amphibians regulates infection with a fungal pathogen
Authors: Ohmer Michel E. B. , Cramp Rebecca L. , Russo Catherine J. M. , White Craig R. , Franklin Craig E.
Published: June 2017

The fungal pathogen Batrachochytrium dendrobatidis (Bd) has been implicated in amphibian population declines globally. Given that Bd infection is limited to the skin in post-metamorphic amphibians, routine skin sloughing may regulate infection. Skin sloughing has been shown to reduce the number of cultivatable microbes on amphibian skin, and Bd infection increases skin sloughing rates at high loads. However, it is unclear whether species specific differences in skin sloughing patterns could regulate Bd population growth on the skin, and influence subsequent infection dynamics. We exposed five Australian frog species to Bd, and monitored sloughing rates and infection loads over time. Sloughing reduced Bd load on the ventral skin surface, in all five species, despite wide variation in susceptibility to disease. In the least susceptible species, an increase in sloughing rate occurred at lower infection loads, and sloughing reduced Bd load up to 100%, leading to infection clearance. Conversely, the drop in Bd load with sloughing was only temporary in the more susceptible species. These findings indicate that the ability of sloughing to act as an effective immune defence is species specific, and they have implications for understanding the pattern of Bd population growth on individual hosts, as well as population-level effects.
Development of a computer-aided design and finite-element analysis combined method for customized Nuss bar in pectus excavatum surgery
Authors: Xie Longhan , Cai Siqi , Xie Liang , Chen Gang , Zhou Haiyu
Published: June 2017

Pectus excavatum (PEX) is the most common chest deformity in children, which is usually corrected by using the minimally invasive Nuss method. The orthopedic effect of the Nuss operation is mainly evaluated by both the Haller index and the appearance of the chest wall configuration, which is dependent on the operator’s clinical experience to a great extent. To improve the orthopedic effect, we proposed a novel method to individually design and optimize the shape of the Nuss bar and to advise its location as well as the incisions. By using the CT imaging data, the three-dimensional model of the PEX thoracic structure is reconstructed, which is further employed in finite element analysis to determine the operation plan. By referring to a healthy person who has similar chest dimensions to the PEX patient, the Nuss bar shape is designed, and according to the finding that the healthy chest wall boundary is almost convex with positive curvature, the Nuss bar shape is tuned to be a convex curve to ensure the orthopedic effect. Finite element analysis is employed to analyze the orthopedic effect and to determine the incision position of the Nuss bar. Experiments were carried out to verify the orthopedic effect of the customized Nuss bar, which showed that this method is more accurate and individualized, compared to conventional methods.
Cognitive and Metacognitive Mechanisms of Change in Metacognitive Training for Depression
Authors: Jelinek Lena , Van Quaquebeke Niels , Moritz Steffen
Published: June 2017

Metacognitive Training for Depression (D-MCT), a low-threshold group intervention, has been shown to improve depressive symptoms. It aims at the reduction of depression by changing dysfunctional cognitive as well as metacognitive beliefs. The purpose of the present study was to investigate whether the mechanisms of change in D-MCT are cognitive (and thus primarily concern the content of cognition) or metacognitive in nature. Eighty-four outpatients with depression were included in a randomized controlled trial comparing D-MCT to an active control intervention. Level of depression, dysfunctional cognitive beliefs (DAS), and metacognitive beliefs (MCQ subscales: Positive Beliefs, Negative Beliefs, Need for Control) were assessed before (t0) and after treatment (t1). Severity of depression was also assessed 6 months later (t2). Linear regression analyses were used to determine whether change in depression from t0 to t2 was mediated by change in cognitive vs. metacognitive beliefs from t0 to t1. D-MCT’s effect on change in depression was mediated by a decrease in dysfunctional metacognitive beliefs, particularly ‘need for control’. Our findings underline that one of the key mechanisms of improvement in D-MCT is the change in metacognitive beliefs. The current study provides further support for the importance of metacognition in the treatment of depression.
Channel branching and zigzagging in negative cloud-to-ground lightning
Authors: Jiang Rubin , Qie Xiushu , Zhang Hongbo , Liu Mingyuan , Sun Zhuling , Lu Gaopeng , Wang Zhichao , Wang Yu
Published: June 2017

A fundamental question in lightning flash concerns why the discharge channel propagates in a zig-zag manner and produces extensive branches. Here we report the optical observation of two negative cloud-to-ground lightning discharges with very high temporal resolution of 180,000 frames per second, which shows in detail the dependence of channel branching and tortuous behavior on the stepping process of the leader development. It is found that the clustered space leaders formed in parallel ahead of the channel tip during an individual step process. The leader branching is due to the multiple connection of the clustered space leaders with the same root channel tip, which occur almost simultaneously, or successively as some space leaders/stems resurrect after interruption. Meanwhile, the irregularity of angles between the clustered space leaders and the advancing direction of leader tip is the origin of channel tortuosity. The statistical analysis on 96 steps shows a geometric-mean value of 4.4 m for the step length, ranging between 1.3 and 8.6 m, while the distance from the center of space leader to the channel is 3.6 m, ranging between 2.1 and 6.9 m. More than 50% steps occurred within an angle range of ±30° from the advancing direction of the leader.
Tunable transport property of oxygen ion in metal oxide thin film: Impact of electrolyte orientation on conductivity
Authors: Arunkumar P. , Ramaseshan R. , Dash S. , Babu K. Suresh
Published: June 2017

Quest for efficient ion conducting electrolyte thin film operating at intermediate temperature (~600 °C) holds promise for the real-world utilization of solid oxide fuel cells. Here, we report the correlation between mixed as well as preferentially oriented samarium doped cerium oxide electrolyte films fabricated by varying the substrate temperatures (100, 300 and 500 °C) over anode/ quartz by electron beam physical vapor deposition. Pole figure analysis of films deposited at 300 °C demonstrated a preferential (111) orientation in out-off plane direction, while a mixed orientation was observed at 100 and 500 °C. As per extended structural zone model, the growth mechanism of film differs with surface mobility of adatom. Preferential orientation resulted in higher ionic conductivity than the films with mixed orientation, demonstrating the role of growth on electrochemical properties. The superior ionic conductivity upon preferential orientation arises from the effective reduction of anisotropic nature and grain boundary density in highly oriented thin films in out-of-plane direction, which facilitates the hopping of oxygen ion at a lower activation energy. This unique feature of growing an oriented electrolyte over the anode material opens a new approach to solving the grain boundary limitation and makes it as a promising solution for efficient power generation.
Invisible noise obscures visible signal in insect motion detection
Authors: Tarawneh Ghaith , Nityananda Vivek , Rosner Ronny , Errington Steven , Herbert William , Cumming Bruce G. , Read Jenny C. A. , Serrano-Pedraza Ignacio
Published: June 2017

The motion energy model is the standard account of motion detection in animals from beetles to humans. Despite this common basis, we show here that a difference in the early stages of visual processing between mammals and insects leads this model to make radically different behavioural predictions. In insects, early filtering is spatially lowpass, which makes the surprising prediction that motion detection can be impaired by “invisible” noise, i.e. noise at a spatial frequency that elicits no response when presented on its own as a signal. We confirm this prediction using the optomotor response of praying mantis Sphodromantis lineola. This does not occur in mammals, where spatially bandpass early filtering means that linear systems techniques, such as deriving channel sensitivity from masking functions, remain approximately valid. Counter-intuitive effects such as masking by invisible noise may occur in neural circuits wherever a nonlinearity is followed by a difference operation.
Serotyping dengue virus with isothermal amplification and a portable sequencer
Authors: Yamagishi Junya , Runtuwene Lucky R. , Hayashida Kyoko , Mongan Arthur E. , Thi Lan Anh Nguyen , Thuy Linh Nguyen , Nhat Cam Nguyen , Limkittikul Kriengsak , Sirivichayakul Chukiat , Sathirapongsasuti Nuankanya , Frith Martin , Makalowski Wojciech , Eshita Yuki , Sugano Sumio , Suzuki Yutaka
Published: June 2017

The recent development of a nanopore-type portable DNA sequencer has changed the way we think about DNA sequencing. We can perform sequencing directly in the field, where we collect the samples. Here, we report the development of a novel method to detect and genotype tropical disease pathogens, using dengue fever as a model. By combining the sequencer with isothermal amplification that only requires a water bath, we were able to amplify and sequence target viral genomes with ease. Starting from a serum sample, the entire procedure could be finished in a single day. The analysis of blood samples collected from 141 Indonesian patients demonstrated that this method enables the clinical identification and serotyping of the dengue virus with high sensitivity and specificity. The overall successful detection rate was 79%, and a total of 58 SNVs were detected. Similar analyses were conducted on 80 Vietnamese and 12 Thai samples with similar performance. Based on the obtained sequence information, we demonstrated that this approach is able to produce indispensable information for etiologically analyzing annual or regional diversifications of the pathogens.
Trilocular phenotype in Brassica juncea L. resulted from interruption of CLAVATA1 gene homologue (BjMc1) transcription
Authors: Xu Ping , Cao Shiqin , Hu Kaining , Wang Xiaohua , Huang Wei , Wang Gang , Lv Zewen , Liu Zhongsong , Wen Jing , Yi Bin , Ma Chaozhi , Tu Jinxing , Fu Tingdong , Shen Jinxiong
Published: June 2017

As a desirable agricultural trait, multilocular trait of rapeseed (Brassica rapa; Brassica napus; Brassica juncea), always represents higher yield per plant compared with bilocular plants. We previously isolated a trilocular gene locus, Bjmc1, and identified a set of molecular markers linked to the trilocular gene. With a map-based cloning, we identified that the BjMc1 was located in B genome of Brassica juncea, and it was a CLAVATA1 (CLV1) gene homologue. The insertion of a copia-LTR retrotransposable element 1 (RTE1) into the coding region of BjMc1 interrupted its transcription in rapeseed, leading to the trilocular phenotype. Phylogenetic analysis showed that Mc1 genes were conserved and widespread in land plants. Two amino acid sites had undergone positive selection in the ancestor of Mc1 genes, and then purifying selection was the dominant force after the divergence of dicots and monocots from their common ancestor in the evolutionary process, indicating that Mc1 genes are conserved in modern land plants. Our results provided new insights in molecular regulatory mechanism of multilocularity in rapeseed, and better understanding of molecular mechanism in crop yield improvement.
Microfluidic co-cultures of retinal pigment epithelial cells and vascular endothelial cells to investigate choroidal angiogenesis
Authors: Chen Li-Jiun , Ito Shuntaro , Kai Hiroyuki , Nagamine Kuniaki , Nagai Nobuhiro , Nishizawa Matsuhiko , Abe Toshiaki , Kaji Hirokazu
Published: June 2017

Angiogenesis plays a critical role in many diseases, including macular degeneration. At present, the pathological mechanisms remain unclear while appropriate models dissecting regulation of angiogenic processes are lacking. We propose an in vitro angiogenesis process and test it by examining the co-culture of human retinal pigmental epithelial cells (ARPE-19) and human umbilical vein endothelial cells (HUVEC) inside a microfluidic device. From characterisation of the APRE-19 monoculture, the tight junction protein (ZO-1) was found on the cells cultured in the microfluidic device but changes in the medium conditions did not affect the integrity of monolayers found in the permeability tests. Vascular endothelial growth factor (VEGF) secretion was elevated under low glucose and hypoxia conditions compared to the control. After confirming the angiogenic ability of HUVEC, the cell-cell interactions were analyzed under lowered glucose medium and chemical hypoxia by exposing ARPE-19 cells to cobalt (II) chloride (CoCl2). Heterotypic interactions between ARPE-19 and HUVEC were observed, but proliferation of HUVEC was hindered once the monolayer of ARPE-19 started breaking down. The above characterisations showed that alterations in glucose concentration and/or oxygen level as induced by chemical hypoxia causes elevations in VEGF produced in ARPE-19 which in turn affected directional growth of HUVEC.
Cathepsin D regulates lipid metabolism in murine steatohepatitis
Authors: Houben Tom , Oligschlaeger Yvonne , Hendrikx Tim , Bitorina Albert V. , Walenbergh Sofie M. A. , van Gorp Patrick J. , Gijbels Marion J. J. , Friedrichs Silvia , Plat Jogchum , Schaap Frank G. , Lütjohann Dieter , Hofker Marten H. , Shiri-Sverdlov Ronit
Published: June 2017

Due to the obesity epidemic, non-alcoholic steatohepatitis (NASH) is a prevalent liver disease, characterized by fat accumulation and inflammation of the liver. However, due to a lack of mechanistic insight, diagnostic and therapeutic options for NASH are poor. Recent evidence has indicated cathepsin D (CTSD), a lysosomal enzyme, as a marker for NASH. Here, we investigated the function of CTSD in NASH by using an in vivo and in vitro model. In addition to diminished hepatic inflammation, inhibition of CTSD activity dramatically improved lipid metabolism, as demonstrated by decreased plasma and liver levels of both cholesterol and triglycerides. Mechanistically, CTSD inhibition resulted in an increased conversion of cholesterol into bile acids and an elevated excretion of bile acids via the feces, indicating that CTSD influences lipid metabolism. Consistent with these findings, treating Wt BMDMs with PepA in vitro showed a similar decrease in inflammation and an analogous effect on cholesterol metabolism. Conclusion: CTSD is a key player in the development of hepatic inflammation and dyslipidemia. Therefore, aiming at the inhibition of the activity of CTSD may lead to novel treatments to combat NASH.
Remodeling of the cycling transcriptome of the oyster Crassostrea gigas by the harmful algae Alexandrium minutum
Authors: Payton Laura , Perrigault Mickael , Hoede Claire , Massabuau Jean-Charles , Sow Mohamedou , Huvet Arnaud , Boullot Floriane , Fabioux Caroline , Hegaret Hélène , Tran Damien
Published: June 2017

As a marine organism, the oyster Crassostrea gigas inhabits a complex biotope governed by interactions between the moon and the sun cycles. We used next-generation sequencing to investigate temporal regulation of oysters under light/dark entrainment and the impact of harmful algal exposure. We found that ≈6% of the gills’ transcriptome exhibits circadian expression, characterized by a nocturnal and bimodal pattern. Surprisingly, a higher number of ultradian transcripts were also detected under solely circadian entrainment. The results showed that a bloom of Alexandrium minutum generated a remodeling of the bivalve’s temporal structure, characterized by a loss of oscillations, a genesis of de novo oscillating transcripts, and a switch in the period of oscillations. These findings provide unprecedented insights into the diurnal landscape of the oyster’s transcriptome and pleiotropic remodeling due to toxic algae exposure, revealing the intrinsic plasticity of the cycling transcriptome in oysters.
Bone morphogenetic protein 4 promotes the survival and preserves the structure of flow-sorted Bhlhb5+ cochlear spiral ganglion neurons in vitro
Authors: Waqas Muhammad , Sun Shan , Xuan Chuanyin , Fang Qiaojun , Zhang Xiaoli , Islam Irum-us , Qi Jieyu , Zhang Shasha , Gao Xia , Tang Mingliang , Shi Haibo , Li Huawei , Chai Renjie
Published: June 2017

SGNs are the primary auditory neurons, and damage or loss of SGNs leads to sensorineural hearing loss. BMP4 is a growth factor that belongs to the TGF-β superfamily and has been shown to play a key role during development, but little is known about its effect on postnatal cochlear SGNs in mice. In this study, we used the P3 Bhlhb5-cre/tdTomato transgenic mouse model and FACS to isolate a pure population of Bhlhb5+ SGNs. We found that BMP4 significantly promoted SGN survival after 7 days of culture. We observed fewer apoptotic cells and decreased expression of pro-apoptotic marker genes after BMP4 treatment. We also found that BMP4 promoted monopolar neurite outgrowth of isolated SGNs, and high concentrations of BMP4 preserved the number and the length of neurites in the explant culture of the modiolus harboring the SGNs. We showed that high concentration of BMP4 enhanced neurite growth as determined by the higher average number of filopodia and the larger area of the growth cone. Finally, we found that high concentrations of BMP4 significantly elevated the synapse density of SGNs in explant culture. Thus, our findings suggest that BMP4 has the potential to promote the survival and preserve the structure of SGNs.
Electrophoresis assisted time-of-flow mass spectrometry using hollow nanomechanical resonators
Authors: Chaudhari Swathi , Chaudhari Kamalesh , Kim Seokbeom , Khan Faheem , Lee Jungchul , Thundat Thomas
Published: June 2017

This report discusses the first demonstration of electrophoresis assisted time-of-flow mass spectrometry using ‘U’ shaped hollow nanomechanical resonators (HNR). Capillary electrophoresis was coupled with the HNR based mass detection to overcome low ionic conductivity of channels embedded in the HNR preventing direct in-situ electrophoretic separation. The flow of analytes through the HNR was achieved by balancing the hydrodynamic pressure to override the electromotive force and inhibit the motion of analytes towards the anode for capillary electrophoresis. The resonance frequency shifts of the HNR vibrating around 1.5 MHz were correlated with the time of the passage of the protein bands to construct the mass spectrum. The proposed concept was demonstrated by constructing a mass spectrum of egg white proteins in the molecular weight range of 14–250 kDa. When compared to regular polyacrylamide gel electrophoresis, our method not only provides a precise and fast readout but also avoids the use of chemical staining. This study paves a new route for low-cost and on-chip mass spectrometers with ultra-miniaturized dimensions.
Brain-derived neurotrophic factor is regulated via MyD88/NF-κB signaling in experimental Streptococcus pneumoniae meningitis
Authors: Xu Danfeng , Lian Di , Zhang Zhijie , Liu Ying , Sun Jiaming , Li Ling
Published: June 2017

Streptococcus pneumoniae meningitis is an intractable disease of the central nervous system (CNS). Brain-derived neurotrophic factor (BDNF) is a member of the neurotrophic family and found to participate in the immune inflammatory response. In this study, we investigated if activation of the classical inflammatory signaling pathway, myeloid differentiation factor 88 (MyD88)/nuclear factor-kappa B (NF-κB), regulates BDNF expression in experimental S. pneumoniae meningitis. MyD88 knockout (myd88−/−) mice and wild-type littermates were infected intracisternally with S. pneumoniae suspension. Twenty-four hours after inoculation, histopathology of brains was evaluated. Cytokine and chemokine in brains and spleens was analyzed using ELISA. NF-κB activation was evaluated using EMSA. Cortical and hippocampal BDNF was assessed using RT-PCR and ELISA, respectively. BDNF promoter activity was evaluated using ChIP-PCR. myd88−/− mice showed an obviously weakened inflammatory host response. This diminished inflammation was consistent with worse clinical parameters, neuron injury, and apoptosis. Deficiency in MyD88 was associated with decreased BDNF expression. Furthermore, we identified a valid κB-binding site in the BDNF promoter, consistent with activation of NF-κB induced by inflammation. To sum up, MyD88/NF-κB signaling has a crucial role in up-regulating BDNF, which might provide potential therapeutic targets for S. pneumoniae meningitis.
A collagen telopeptide binding peptide shows potential in aiding collagen bundle formation and fibril orientation
Authors: Yang Wenyu , Li Lin , Su Guanghao , Zhang Zhe , Cao Yiting , Li Xuemin , Shi Yanping , Zhang Qiqing
Published: June 2017

A double-armed CTBP-PEG-CTBP derivative of a collagen telopeptide binding peptide (CTBP), shows potential in aiding collagen bundle formation and fibril orientation by interacting with fibrils.
Glycocalyx scaffolding with synthetic nanoscale glycomaterials
Authors: Huang Mia L. , Purcell Sean C. , Verespy III Stephen , Wang Yinan , Godula Kamil
Published: June 2017

A cell surface engineering method allows for building glycan complexity with control over nanoscale presentation.
Stretch-dependent changes in molecular conformation in fibronectin nanofibers
Authors: Szymanski John M. , Sevcik Emily N. , Zhang Kairui , Feinberg Adam W.
Published: June 2017

Engineered fibronectin nanofibers reveal a nodular to fibrillar transformation in molecular conformation during 7-fold extension.
Significance of isomeric reaction intermediates in the hydrogenolysis of glycerol to 1,2-propanediol with Cu-based catalysts
Authors: Vila F. , López Granados M. , Mariscal R.
Published: June 2017

The 2,3-enediol isomer was identified as the most favorable isomer to give 1,2-PDO.
Reduction of carbon dioxide and organic carbonyls by hydrosilanes catalysed by the perrhenate anion
Authors: Morris Danny S. , Weetman Catherine , Wennmacher Julian T. C. , Cokoja Mirza , Drees Markus , Kühn Fritz E. , Love Jason B.
Published: June 2017

A simple quaternary ammonium perrhenate salt catalyses the hydrosilylation of aldehydes, ketones, and carbon dioxide, and the methylation of amines using carbon dioxide. DFT calculations show that a perrhenate hypervalent silicate interacts directly with CO2.
The first ReI organometallic complex with an organoimido-polyoxometalate ligand
Authors: Hermosilla-Ibáñez Patricio , Wrighton-Araneda Kerry , Prado Gaspar , Paredes-García Verónica , Pizarro Nancy , Vega Andrés , Venegas-Yazigi Diego
Published: June 2017

An electrochemical, spectroscopic and theoretical study of the first ReI complex with a hybrid organoimido-polyoxometalate ligand is presented.
Stabilisation of gold nanoparticles by N-heterocyclic thiones
Authors: Moraes Leonardo C. , Lacroix Bertrand , Figueiredo Rute C. , Lara Patricia , Rojo Javier , Conejero Salvador
Published: June 2017

Gold nanoparticles (Au-NPs) have been prepared using N-heterocyclic thiones (NHTs) as ligand stabilisers.
Fast & easy preparation of 3D scaffolds from methyl benzoate by a diversity oriented synthesis strategy based on Diels–Alder and ene-reactions
Authors: Brossard Dominique , Retailleau Pascal , Dumontet Vincent , Breton Philippe , Desrat Sandy , Roussi Fanny
Published: June 2017

Thermic dimerization of methyl 1,3-cyclohexadiene 2-carboxylate gave original 3D-shape compounds by Diels–Alder cycloaddition and original [6 + 4]-ene reaction.
Fast profiling of metabolite mixtures using chemometric analysis of a speeded-up 2D heteronuclear correlation NMR experiment
Authors: Sharma Rakesh , Gogna Navdeep , Singh Harpreet , Dorai Kavita
Published: June 2017

One-dimensional (1D) NMR spectra of mixtures of metabolites suffer from severe overlap of spectral resonances and hence recent research in NMR-based metabolomics focuses on using two-dimensional (2D) NMR experiments for metabolite fingerprinting.
Dual role of polyphosphoric acid-activated nitroalkanes in oxidative peri-annulations: efficient synthesis of 1,3,6,8-tetraazapyrenes
Authors: Aksenov Alexander V. , Ovcharov Dmitrii S. , Aksenov Nicolai A. , Aksenov Dmitrii A. , Nadein Oleg N. , Rubin Michael
Published: June 2017

Electrophilically activated nitroalkanes play a dual role in the novel reaction with diaminoperimidines, promoting their oxidative peri-annulation to access tetraazapyrenes.
A fluorescent photochromic diarylethene based on naphthalic anhydride with strong solvatochromism
Authors: Chen Shangjun , Li Xin , Song Liwen
Published: June 2017

A diarylethene molecule consisting of an 1,8-naphthalic anhydride and two 2,5 dimethylthiophene which exhibits reversible fluorescence switching capacity as well as solvatochromism with red shift of the fluorescence maximum by more than 150 nm.
Density dependence of orientational order in one-patch particles
Authors: Iwashita Yasutaka , Kimura Yasuyuki
Published: June 2017

Orientational order in slightly aspherical one-patch particles sensitively depends on packing density when closely packed.
Output enhanced compact multilayer flexible nanogenerator for self-powered wireless remote system
Authors: Wu Nan , Jiang Hulin , Li Wenbo , Lin Shizhe , Zhong Junwen , Yuan Fang , Huang Liang , Hu Bin , Zhou Jun
Published: June 2017

A simple-structured compact multilayer flexible nanogenerator was demonstrated in this work. The power density of the nanogenerator could be optimized by structural controlling. This strategy may pave a new way for self-powered electronic systems.
Optimal PMU placement considering state estimation uncertainty and voltage controllability
Authors: Zhang Chunxue , Jia Youwei , Xu Zhao , Lai Loi Lei , Wong Kit Po
Published: June 2017

The development of monitoring technologies in smart grid is undergoing an essential transition from periodical magnitude‐based measurement by supervisory control and data acquisition (SCADA) to real‐time phasor measurement unit (PMU)‐based wide area monitoring and control. The implementation of PMUs can substantially facilitate grid‐wide state estimation and operation control, which is dependent on an effective PMU placement strategy. In this study, the optimal PMU placement (OPP) problem is investigated with respect to zonal voltage controllability and voltage magnitude estimation in cooperation with SCADA. In particular, the OPP is formulated as a multi‐objective minimal Ncut partitioning problem, in which various operating scenarios are represented by probabilistic load flows to achieve a general solution for planning purpose. Spectral clustering is employed to efficiently find the optimal clustering boundaries, which indicate the resulting placement layout. The proposed placement scheme is tested on New England 39‐bus and IEEE 118‐bus systems. Simulation results demonstrate the effectiveness of the proposed approach.
Improved robust adaptive backstepping control approach on STATCOM for non‐linear power systems
Authors: Su Qingyu , Quan Wanzhen , Quan Weiwei , Cai Guowei , Li Jian
Published: June 2017

The problem of large disturbance attenuation in the single‐machine infinite‐bus system with a static synchronous compensator (STATCOM) is proposed to be alleviated by an improved robust backstepping algorithm, which utilises error compensation and sliding mode variable structure control methods to achieve stability. For STATCOM systems with internal and external disturbances, the adaptive backstepping method is used to construct the storage function, and a non‐linear gain interference rejection controller and parameter substitution law are applied simultaneously. The improved method differs from the traditional adaptive backstepping design in terms of error‐compensation design methodology, in order to ensure robustness and insensitivity to large disturbances of the STATCOM system, and furthermore, preserving useful non‐linearities and the real‐time estimation of uncertain parameters. Finally, a simulation demonstrates that the improved method is more efficient than traditional adaptive backstepping with respect to the speed of adaptation and the response of the STATCOM system. Hence, the effectiveness and practicality of the proposed control method is demonstrated by engineers in applications.
Adenosine triphosphate diffusion through poly(ethylene glycol) diacrylate hydrogels can be tuned by cross-link density as measured by PFG-NMR
Authors: Majer Günter , Southan Alexander
Published: June 2017

The diffusion of small molecules through hydrogels is of great importance for many applications. Especially in biological contexts, the diffusion of nutrients through hydrogel networks defines whether cells can survive inside the hydrogel or not. In this contribution, hydrogels based on poly(ethylene glycol) diacrylate with mesh sizes ranging from ξ = 1.1 to 12.9 nm are prepared using polymers with number-average molecular weights between Mn = 700 and 8000 g/mol. Precise measurements of diffusion coefficients D of adenosine triphosphate (ATP), an important energy carrier in biological systems, in these hydrogels are performed by pulsed field gradient nuclear magnetic resonance. Depending on the mesh size, ξ, and on the polymer volume fraction of the hydrogel after swelling, ϕ, it is possible to tune the relative ATP diffusion coefficient D/D0 in the hydrogels to values between 0.14 and 0.77 compared to the ATP diffusion coefficient D0 in water. The diffusion coefficients of ATP in these hydrogels are compared with predictions of various mathematical expressions developed under different model assumptions. The experimental data are found to be in good agreement with the predictions of a modified obstruction model or the free volume theory in combination with the sieving behavior of the polymer chains. No reasonable agreement was found with the pure hydrodynamic model.
Raman scattering of circularly polarized laser beam in homogeneous and inhomogeneous magnetized plasma channel
Authors: Ghaffari-Oskooei S. S. , Aghamir F. M.
Published: June 2017

Raman scattering of circularly polarized laser beams in a magnetized plasma channel is investigated. The scattering is considered as parametric instability. Dispersion relations of backward and forward scattered waves in a magnetized plasma are derived in a weakly relativistic regime. Growth rates of the corresponding instabilities are calculated. The effects of laser intensity and its polarization as well as the strength of the magnetic field and corresponding cyclotron frequency along with plasma density and its inhomogeneity on the growth rate of Raman scattering are examined. The study shows that the left-handed circularly polarized laser beam has different behaviors in comparison to the right-handed beam, and their growth rates are different due to the anisotropic properties of the magnetized plasma. In addition, Raman scattering in an inhomogeneous plasma with a linear density profile is investigated. The comparison between homogeneous and inhomogeneous plasmas has indicated that inhomogeneity reduces the growth rate. The frequency shift of scattered waves, when laser intensity is high, is studied in the magnetized plasma. The findings indicate that the shift depends on laser intensity and its polarization as well as plasma density and dc magnetic field. The frequency shift can be used as a diagnostic tool for density measurement in laser-plasma interactions.
Ionic versus metallic bonding in AlnNam and AlnMgm (m ≤ 3, n + m ≤ 15) clusters
Authors: Grover Cameron J. , Reber Arthur C. , Khanna Shiv N.
Published: June 2017

First principles electronic structure studies on the ground state geometries, stability, and the electronic structure of AlnNam and AlnMgm (m ≤ 3, n + m ≤ 15) clusters have been carried out to examine the nature of bonding between Na or Mg and Al. Identifying whether the bonding is ionic or metallic in bulk materials is typically straightforward; however, in small clusters where quantum confinement is important, the nature of bonding may become unclear. We have performed a critical analysis of the bonding in these bimetallic clusters using charge analysis, electrical dipole moments, hybridization of the atomic orbitals, the Laplacian of the charge density at the bond critical points, and the change in the bonding energy between neutral and anionic forms of the cluster. For NanAlm clusters, we find that the Na binding is primarily ionic, while the bonding in AlnMgm is primarily metallic. We find that the Mulliken population of the 3p orbital of Na and Mg can provide a rapid assessment of the nature of bonding. We also find that the Hirshfeld charge and dipole moments are effective indicators, when placed in context. We found that the Laplacian of the charge density at the bond critical points can be misleading in identifying whether the bonding is ionic or metallic in small clusters.
Hydrogen anion and subgap states in amorphous In–Ga–Zn–O thin films for TFT applications
Authors: Bang Joonho , Matsuishi Satoru , Hosono Hideo
Published: June 2017

Hydrogen is an impurity species having an important role in the physical properties of semiconductors. Despite numerous studies, the role of hydrogen in oxide semiconductors remains an unsolved puzzle. This situation arises from insufficient information about the chemical state of the impurity hydrogen. Here, we report direct evidence for anionic hydrogens bonding to metal cations in amorphous In–Ga–Zn–O (a-IGZO) thin films for thin-film transistors (TFT) applications and discuss how the hydrogen impurities affect the electronic structure of a-IGZO. Infrared absorption spectra of self-standing a-IGZO thin films prepared by sputtering reveal the presence of hydrogen anions as a main hydrogen species (concentration is ∼1020 cm−3) along with the hydrogens in the form of the hydroxyl groups (∼1020 cm−3). Density functional theory calculations show that bonds between these hydride ions with metal centers give rise to subgap states above the top of the valence band, implying a crucial role of anionic hydrogen in the negative bias illumination stress instability commonly observed in a-IGZO TFTs.
Multi-stacked GaSb/GaAs type-II quantum nanostructures for application to intermediate band solar cells
Authors: Shoji Yasushi , Tamaki Ryo , Okada Yoshitaka
Published: June 2017

We have investigated the performance of 10-layer stacked GaSb/GaAs quantum dot (QD) and quantum ring (QR) solar cells (SCs) having a type-II band alignment. For both SCs, the external quantum efficiency (EQE) increased in the longer wavelength region beyond GaAs bandedge wavelength of λ > 870 nm due to an additive contribution from GaSb/GaAs QD or QR layers inserted in the intrinsic region of p-i-n SC structure. The EQE of GaSb/GaAs QRSC was higher than that of QDSC at room temperature and the photoluminescence intensity from GaSb/GaAs QRs was stronger compared with GaSb/GaAs QDs. These results indicate that crystal quality of GaSb/GaAs QRs is superior to that of GaSb/GaAs QDs. Furthermore, a photocurrent production due to two-step photo-absorption via GaSb/GaAs QD states or QR states, ΔEQE was measured at low temperature and the ratio of two-step absorption to total carrier extraction defined as ΔEQE / (ΔEQE + EQE), was higher for GaSb/GaAs QRSC than that of QDSC. The ratio of GaSb/GaAs QRSC exceeds 80% over the wavelength region of λ = 950 - 1250 nm. This suggests that two-step absorption process is more dominant for carrier extraction from GaSb/GaAs QR structure.
Larval trypanorhynch cestodes in teleost fish from Moreton Bay, Queensland
Authors: Beveridge I. , Cribb T. H. , Cutmore S. C.
Published: June 2017

During a helminthological examination of teleost fish of Moreton Bay (Qld, Australia), 976 fish from 13 orders, 57 families and 133 species were examined and nine species of trypanorhynch metacestodes were identified. Callitetrarhynchus gracilis (Rudolphi, 1819) was the most frequently encountered species, found in 16 species of fish, with Callitetrarhynchus speciosus (Linton, 1897), Pterobothrium pearsoni (Southwell, 1929), Otobothrium alexanderi Palm, 2004, Otobothrium mugilis Hiscock, 1954, Otobothrium parvum Beveridge & Justine, 2007, Proemotobothrium southwelli Beveridge & Campbell, 2001, Pseudotobothrium dipsacum (Linton, 1897) and Heteronybelinia cf. heteromorphi Palm, 1999 occurring in fewer host species and at lower prevalences. Comparisons are made with studies elsewhere in the world and specifically within the South-west Pacific. Of the best studied regions in the South-west Pacific (Heron Island, Lizard Island, New Caledonia and now Moreton Bay), the fauna from Moreton Bay was found to be the most distinctive, with fauna from the three reef locations sharing 35–48% of species between sites and just 12–24% with Moreton Bay. The fauna of trypanorhynch cestodes from Lizard Island and New Caledonia was found to be the most similar.
Economic development, flow of funds, and the equilibrium interaction of financial frictions
Authors: Moll Benjamin , Townsend Robert M. , Zhorin Victor
Published: June 2017

Significance

Variation in the type of financial frictions faced by households and firms is an overlooked dimension of regional heterogeneity that has the potential to explain cross-regional factor flows and differences in concentration of economic activity. Our research combines a theoretical model with a complexity and variety of data from Thailand. The theoretical model features variation in financial regimes, moral hazard, and limited commitment, inferred from the data. In a counterfactual experiment we explore the effects of protecting wages in urban areas from incoming migrants and protecting rural areas from capital outflow. Economic life in cities would suffer enormously, as would rural and national productivity, with an increase in overall inequality.
Grain boundary precipitation in Inconel 718 and ATI 718Plus
Authors: Hassan Bilal , Corney Jonathan
Published: June 2017

Grain boundary precipitates in Inconel 718 and ATI 718Plus are important to control during hot working processes, since they can control the grain size. Precipitating excessive or insufficient amounts can be detrimental to the final component. Therefore, it is important for manufacturers to understand the formation and kinetics of grain boundary precipitation and the effect this has on mechanical properties. This review considers the background of grain boundary precipitation, including the effect of the thermal stability of γ′ and γ″ phases. In addition, the effect of stress on the grain boundary phases and their precipitation kinetics in different conditions are also included. Also, the impact of grain boundary precipitation on the mechanical properties is explored.

This review was submitted as part of the 2017 Materials Literature Review Prize of the Institute of Materials, Minerals and Mining run by the Editorial Board of MST. Sponsorship of the prize by TWI Ltd is gratefully acknowledged
Nitrate analogs as attractants for soybean cyst nematode
Authors: Hosoi Akito , Katsuyama Tsutomu , Sasaki Yasuyuki , Kondo Tatsuhiko , Yajima Shunsuke , Ito Shinsaku
Published: June 2017

Soybean cyst nematode (SCN) Heterodera glycines Ichinohe, a plant parasite, is one of the most serious pests of soybean. In this paper, we report that SCN is attracted to nitrate and its analogs. We performed attraction assays to screen for novel attractants for SCN and found that nitrates were attractants for SCN and SCN recognized nitrate gradients. However, attraction of SCN to nitrates was not observed on agar containing nitrate. To further elucidate the attraction mechanism in SCN, we performed attraction assays using nitrate analogs (, , ). SCN was attracted to all nitrate analogs; however, attraction of SCN to nitrate analogs was not observed on agar containing nitrate. In contrast, SCN was attracted to azuki root, irrespective of presence or absence of nitrate in agar media. Our results suggest that the attraction mechanisms differ between plant-derived attractant and nitrate.
Ex-Centric Hermeneutics in Stephanus Muller's Nagmusiek
Authors: Froneman Willemien
Published: June 2017

In this review article the author reads Nagmusiek – Stephanus Muller's monumental metafictional biography of South African composer Arnold van Wyk – as an extended allegory on the geopolitics of academic writing. She argues that the book articulates, through its unusual physical apparatus, narratological techniques and metafictional hermeneutic deconcealment, a valuable theory-in-praxis of the aporetics of peripheral writing. In so doing, Muller materializes Walter Mignolo's notion of ‘epistemic delinking’ in radically original and risky ways.
Investigation of radon level in air and tap water of workplaces at Thailand Institute of Nuclear Technology, Thailand
Authors: Sola P , Youngchuay U , Kongsri S , Kongtana A
Published: June 2017

Thailand Institute of Nuclear Technology (TINT) has continuously monitored radiation exposure and radionuclide in workplaces specifically radon gas to estimate effective dose for workers. Radon exposure is the second leading cause of lung cancer in the world. In this study, radon in air and tap water at building no. 3, 7, 8, 9 and 18 on Ongkharak site of TINT have been measured for 5 years from 2012 to 2016. Radon level in air and tap water were investigated on 83 stations (workplaces) and 54 samples, respectively. Radon concentrations in air and tap water were measured by using the pulsed ionization chamber (ATMOS 12 DPX). Indoor radon concentrations in air were in the range of 12-138 Bq.m-3 with an average value of 30.13±17.05 Bq.m-3. Radon concentrations in tap water were in the range of 0.10 to 2.89 Bq.l-1 with an average value of 0.51±0.55 Bq.l-1. The results of radon concentrations at TINT were below the US Environmental Protection Agency (US EPA) safety limit of 148 Bq.m-3 and 150 Bq.l-1, for, air and tap water, respectively. The average effective dose for TINT’s workers due to indoor radon exposure was approximately 0.20±0.11 mSv.y-1. The value is 100 times less than the annual dose limit for limit occupational radiation worker defined by the International Commission on Radiological Protection (ICRP). As a result, the TINT’s workplaces are radiologically safe from radon content in air and tap water.
A cytoskeletal clutch mediates cellular force transmission in a soft, three-dimensional extracellular matrix
Authors: Owen Leanna M. , Adhikari Arjun S. , Patel Mohak , Grimmer Peter , Leijnse Natascha , Kim Min Cheol , Notbohm Jacob , Franck Christian , Dunn Alexander R.
Published: June 2017

The ability of cells to impart forces and deformations on their surroundings underlies cell migration and extracellular matrix (ECM) remodeling and is thus an essential aspect of complex, metazoan life. Previous work has resulted in a refined understanding, commonly termed the molecular clutch model, of how cells adhering to flat surfaces such as a microscope coverslip transmit cytoskeletally generated forces to their surroundings. Comparatively less is known about how cells adhere to and exert forces in soft, three-dimensional (3D), and structurally heterogeneous ECM environments such as occur in vivo. We used time-lapse 3D imaging and quantitative image analysis to determine how the actin cytoskeleton is mechanically coupled to the surrounding matrix for primary dermal fibroblasts embedded in a 3D fibrin matrix. Under these circumstances, the cytoskeletal architecture is dominated by contractile actin bundles attached at their ends to large, stable, integrin-based adhesions. Time-lapse imaging reveals that α-actinin-1 puncta within actomyosin bundles move more quickly than the paxillin-rich adhesion plaques, which in turn move more quickly than the local matrix, an observation reminiscent of the molecular clutch model. However, closer examination did not reveal a continuous rearward flow of the actin cytoskeleton over slower moving adhesions. Instead, we found that a subset of stress fibers continuously elongated at their attachment points to integrin adhesions, providing stable, yet structurally dynamic coupling to the ECM. Analytical modeling and numerical simulation provide a plausible physical explanation for this result and support a picture in which cells respond to the effective stiffness of local matrix attachment points. The resulting dynamic equilibrium can explain how cells maintain stable, contractile connections to discrete points within ECM during cell migration, and provides a plausible means by which fibroblasts contract provisional matrices during wound healing.
Group galaxy number density profiles far out: Is the ‘one-halo’ term NFW out to >10 virial radii?
Authors: Trevisan M. , Mamon G. A. , Stalder D. H.
Published: June 2017

While the density profiles (DPs) of Lambda cold dark matter haloes obey the Navarro, Frenk & White (NFW) law out to roughly one virial radius, rvir, the structure of their outer parts is still poorly understood, because the one-halo term describing the halo itself is dominated by the two-halo term representing the other haloes picked up. Using a semi-analytical model, we measure the real-space one-halo number DP of groups out to 20rvir by assigning each galaxy to its nearest group above mass Ma, in units of the group rvir. If Ma is small (large), the outer DP of groups falls rapidly (slowly). We find that there is an optimal Ma for which the stacked DP resembles the NFW model to 0.1 dex accuracy out to 13 virial radii. We find similar long-range NFW surface DPs (out to 10rvir) in the Sloan Digital Sky Survey observations using a galaxy assignment scheme that combines the non-linear virialized regions of groups with their linear outer parts. The optimal Ma scales as the minimum mass of the groups that are stacked to a power 0.25–0.3. The NFW model thus does not solely originate from violent relaxation. Moreover, populating haloes with galaxies using halo occupation distribution models must proceed out to much larger radii than usually done.