bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis of High Crystalline TiO2 Nanoparticles on a Polymer Membrane to Degrade Pollutants from Water
Authors: Fischer Kristina , Schulz Paulina , Atanasov Igor , Abdul Latif Amira , Thomas Isabell , Kühnert Mathias , Prager Andrea , Griebel Jan , Schulze Agnes
Published: September 2018

Titanium dioxide (TiO2) is described as an established material to remove pollutants from water. However, TiO2 is still not applied on a large scale due to issues concerning, for example, the form of use or low photocatalytic activity. We present an easily upscalable method to synthesize high active TiO2 nanoparticles on a polyethersulfone microfiltration membrane to remove pollutants in a continuous way. For this purpose, titanium(IV) isopropoxide was mixed with water and hydrochloric acid and treated up to 210 °C. After cooling, the membrane was simply dip-coated into the TiO2 nanoparticle dispersion. Standard characterization was undertaken (i.e., X-ray powder diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy, water permeance, contact angle). Degradation of carbamazepine and methylene blue was executed. By increasing synthesis temperature crystallinity and photocatalytic activity elevates. Both ultrasound modification of nanoparticles and membrane pre-modification with carboxyl groups led to fine distribution of nanoparticles. The ultrasound-treated nanoparticles gave the highest photocatalytic activity in degrading carbamazepine and showed no decrease in degradation after nine times of repetition. The TiO2 nanoparticles were strongly bound to the membrane. Photocatalytic TiO2 nanoparticles with high activity were synthesized. The innovative method enables a fast and easy nanoparticle production, which could enable the use in large-scale water cleaning.
Optimization and Tunability of 2D Graphene and 1D Carbon Nanotube Electrocatalysts Structure for PEM Fuel Cells
Authors: Remy Emeline , Thomas Yohann. R. J. , Guetaz Laure , Fouda-Onana Frédéric , Jacques Pierre-André , Heitzmann Marie
Published: September 2018

In this work, N-doped Multi-Walled Carbon Nanotubes (MWCNTs) and Few Graphene Layers (FGLs) have been functionalized with platinum nanoparticles using two methods starting with hexachloroplatinic acid as precursor: (i) ethylene glycol (EG) reduction and (ii) impregnation followed by reduction in hydrogen atmosphere. Morphological scanning transmission electron microscopy (STEM) analyses showed a homogenous dispersion of metal particles with narrow-size distribution onto both carbon supports (Pt/C loadings between 30 wt % and 40 wt %). Electrocatalytic properties of the as-synthetized catalysts toward the Oxygen Reduction Reaction (ORR) was evaluated in aqueous electrolyte using a three electrodes electrochemical cell by cyclic voltammetry (CV) in rotating disk electrode (RDE). It is shown that a mixture of Pt supported on MWCNT and FGLs allows to enhance both the electrochemical surface area and the activity of the catalyst layer. Ageing tests performed on that optimized active layer showed higher stability than conventional Pt/C.
Special Issues in the Application of Seismic Isolation to Nuclear Power Plants
Authors: Zhou Zhiguang , Hu Xiaorong , Wong Jenna
Published: September 2018

While seismic isolation is one of the principal approaches used to mitigate the risks associated with earthquake ground shaking, it has found only limited application in the construction of nuclear power plants (NPPs). As a new application, it is necessary to understand how the overall process works and figure out potential difficulties in all stages of managing isolated NPPs. Several manufacturers, experts, and representatives from engineering firms were contacted and interviewed to better understand potential difficulties in the application of seismic isolation to NPPs. In addition to this firsthand knowledge, studies and research conducted in the area of radiation exposure and the area of general durability are reviewed. According to these materials, this paper summarizes some issues related to the durability of the isolators, radiation, and other environmental effects on devices and raises some understanding and special issues in the planning, design, analysis, procurement, installation, operations, and maintenance stages of managing a seismically isolated NPP. These topics are expected to provide a certain guiding significance on future application of seismic isolation for NPPs.
Coordination and Private Information Revelation
Authors: Saha Debdatta , Roy Chowdhury Prabal
Published: September 2018

This paper examines a persuasion game between two agents with one-sided asymmetric information, where the informed agent can reveal her private information prior to playing a Battle-of-the-Sexes coordination game. There is a close connection between the extent of information revelation and the possibility of coordination failure; while, in the absence of any coordination failure, there exist equilibria with full disclosure, in the presence of strategic uncertainty in coordination there exists an equilibrium with no information revelation. We provide a purification argument for the non-existence result, as well demonstrate that it is robust to several extensions, including both-sided asymmetric information and imprecise information revelation.
The Association of the 24 Hour Distribution of Time Spent in Physical Activity, Work, and Sleep with Emotional Exhaustion
Authors: Janurek Janina , Abdel Hadi Sascha , Mojzisch Andreas , Häusser Jan Alexander
Published: September 2018

Previous research identified time spent in physical activity, sleeping, and working as predictors of emotional exhaustion. However, this research did not take into account the interdependence of these time-use components. Since daily time is limited to 24 h, time spent in one specific activity (e.g., sleep) cannot be used for any other activity (e.g., physical activity). We conducted a one-week daily sampling study to assess the compositional effects of physical activity, sleep, and work on emotional exhaustion. Since the sample consisted of 104 undergraduate students, work was operationalized as study time. Participants wore accelerometers for one week continuously to assess sleep and physical activity. Also, they filled in questionnaires on study time and emotional exhaustion every morning. Multilevel and compositional data analyses were conducted. The multilevel analysis revealed significant between- (p = 0.012) and within-level (p < 0.001) associations of study time with emotional exhaustion. The compositional approach showed that time spent in physical activity was negatively related to emotional exhaustion (p = 0.007), whereas time spent studying was positively related to emotional exhaustion (p = 0.003), relative to the remaining two time-use components. In conclusion, our results show that emotional exhaustion is not only associated with work-related factors, but also with off-job physical activity.
Simulations of NPC1(NTD):NPC2 Protein Complex Reveal Cholesterol Transfer Pathways
Authors: Hodošček Milan , Elghobashi-Meinhardt Nadia
Published: September 2018

The Niemann Pick type C (NPC) proteins, NPC1 and NPC2, are involved in the lysosomal storage disease, NPC disease. The formation of a NPC1–NPC2 protein–protein complex is believed to be necessary for the transfer of cholesterol and lipids out of the late endosomal (LE)/lysosomal (Lys) compartments. Mutations in either NPC1 or NPC2 can lead to an accumulation of cholesterol and lipids in the LE/Lys, the primary phenotype of the NPC disease. We investigated the NPC1(NTD)–NPC2 protein–protein complex computationally using two putative binding interfaces. A combination of molecular modeling and molecular dynamics simulations reveals atomic details that are responsible for interface stability. Cholesterol binding energies associated with each of the binding pockets for the two models are calculated. Analyses of the cholesterol binding in the two models support bidirectional ligand transfer when a particular interface is established. Based on the results, we propose that, depending on the location of the cholesterol ligand, a dynamical interface between the NPC2 and NPC1(NTD) proteins exists. Structural features of a particular interface can lower the energy barrier and stabilize the passage of the cholesterol substrate from NPC2 to NPC1(NTD).
Performance Analysis of Maximum Likelihood Estimation for Transmit Power Based on Signal Strength Model
Authors: Hu Xiao-Li , Ho Pin-Han , Peng Limei
Published: September 2018

We study theoretical performance of Maximum Likelihood (ML) estimation for transmit power of a primary node in a wireless network with cooperative receiver nodes. The condition that the consistence of an ML estimation via cooperative sensing can be guaranteed is firstly defined. Theoretical analysis is conducted on the feasibility of the consistence condition regarding an ML function generated by independent yet not identically distributed random variables. Numerical experiments justify our theoretical discoveries.
Enhanced Electrical Properties of Atomic Layer Deposited LaxAlyO Thin Films with Stress Relieved Preoxide Pretreatment
Authors: Wang Xing , Liu Hongxia , Zhao Lu , Wang Yongte
Published: September 2018

The impact of stress relieved preoxide (SRPO) interface engineering on the physical and electrical properties of LaxAlyO films was investigated. It was proved that the SRPO pretreatment has little influence on the surface morphology of LaxAlyO films and the chemical bond composition of LaxAlyO/Si interface. However, the SRPO pretreated MIS capacitor displayed obvious improvement in decreasing the amount of trapped oxide charges and interfacial traps. As a result, a reduction of more than one order of magnitude in the gate leakage current density was obtained. The breakdown field strength and TDDB reliability of the LaxAlyO film treated with SRPO were also enhanced.
Dye-Sensitized Solar Cells with Electrospun Nanofiber Mat-Based Counter Electrodes
Authors: Juhász Junger Irén , Wehlage Daria , Böttjer Robin , Grothe Timo , Juhász László , Grassmann Carsten , Blachowicz Tomasz , Ehrmann Andrea
Published: September 2018

Textile-based dye-sensitized solar cells (DSSCs) can be created by building the necessary layers on a textile fabric or around fibers which are afterwards used to prepare a textile layer, typically by weaving. Another approach is using electrospun nanofiber mats as one or more layers. In this work, electrospun polyacrylonitrile (PAN) nanofiber mats coated by a conductive polymer poly(3,4-ethylenedioxythiopene) polystyrene sulfonate (PEDOT:PSS) were used to produce the counter electrodes for half-textile DSSCs. The obtained efficiencies were comparable with the efficiencies of pure glass-based DSSCs and significantly higher than the efficiencies of DSSCs with cotton based counter electrodes. The efficiency could be further increased by increasing the number of PEDOT:PSS layers on the counter electrode. Additionally, the effect of the post treatment of the conductive layers by HCl, acetic acid, or dimethyl sulfoxide (DMSO) on the DSSC efficiencies was investigated. Only the treatment by HCl resulted in a slight improvement of the energy-conversion efficiency.
Diagnosis of Idiopathic Pulmonary Fibrosis: Differential Diagnosis
Authors: Aburto Myriam , Herráez Inmaculada , Iturbe David , Jiménez-Romero Ana
Published: September 2018

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive, and fibrotic interstitial lung disease of unknown origin with a characteristic imaging and histologic pattern called usual interstitial pneumonia (UIP). The diagnosis of IPF is a complex procedure that requires the support of various specialists, who must integrate clinical, radiological, and histological data. The multidisciplinary team (MDT) has become the new gold standard to diagnose and manage the disease, increasing the accuracy and agreement of the diagnosis between different centers. It is mandatory to exclude nonspecific interstitial pneumonia or other diseases that can cause the UIP pattern, particularly drugs or exposure diseases, including chronic hypersensitivity pneumonitis or systemic autoimmune disease. The role of the MDT is also to decide who could need a biopsy or to review patient diagnoses at regular intervals in those with additional information or unexpected evolution. This review provides updated information to achieve a proper IPF diagnosis.
Rock Classification Using Multivariate Analysis of Measurement While Drilling Data: Towards a Better Sampling Strategy
Authors: Vezhapparambu Veena S. , Eidsvik Jo , Ellefmo Steinar L.
Published: September 2018

Measurement while drilling (MWD) data are gathered during drilling operations and can provide information about the strength of the rock penetrated by the boreholes. In this paper MWD data from a marble open-pit operation in northern Norway are studied. The rock types are represented by discrete classes, and the data is then modeled by a hidden Markov model (HMM). Results of using different MWD data variables are studied and presented. These results are compared and co-interpreted with optical televiewer (OTV) images, magnetic susceptibility and spectral gamma values collected in the borehole using down-the-hole sensors. A model with penetration rate, rotation pressure and dampening pressure data show a good visual correlation with OTV image for the studied boreholes. The marble class is characterized by medium penetration rate and medium rotation pressure, whereas the intrusions are characterized by low penetration rate and medium to high rotation pressure. The fractured marble is characterized by high penetration rate, high rotation and low dampening pressure. Future research will use the presented results to develop a heterogeneity index, develop an MWD-based 3D-geology model and an improved sampling strategy and investigate how to implement this in the mine planning process and reconciliation.
Protection against UVB-Induced Wrinkle Formation in SKH-1 Hairless Mice: Efficacy of Tricin Isolated from Enzyme-Treated Zizania latifolia Extract
Authors: Moon Joo-Myung , Park Se-Ho , Jhee Kwang-Hwan , Yang Seun-Ah
Published: September 2018

Tricin, a flavone found mainly in rice bran and sugarcane, has various beneficial effects. It has proven to be a clinically safe and selective potent inhibitor of different cancer cell lines. In this study, we evaluated the efficacy of enzyme-treated Zizania latifolia (ETZL) and its major active compound tricin on skin photoaging in SKH-1 hairless mice. Tricin (0.3 mg/kg) and ETZL (50, 150, and 300 mg/kg) were orally administrated to mice for 14 weeks; no cytotoxicity was observed during the entire experimental period. After UVB exposure, we observed significant increases in keratinization, coarse wrinkles, loss of moisture, thickened epidermis, and collagen fiber degradation in the dorsal skin. These features of photoaging were significantly suppressed after oral administration of tricin or ETZL. In addition, the protein expression of collagen effectively increased in ETZL (150 and 300 mg/kg)-treated mice, while the increased metalloproteinase (MMP)-1 and MMP-3 expressions were reduced after exposure to tricin or ETZL, although the effects were not dose-dependent. These data indicate that ETZL may be effective for attenuation of UVB-induced skin damage and photoaging in hairless mice, possibly by inhibiting MMPs expression.
Phospholipid and Lipid Derivatives as Potential Neuroprotective Compounds
Authors: Tayebati Seyed Khosrow
Published: September 2018

The worldwide demographical trend is changing towards a more elderly population. In particular, this phenomenon is increasing the number of neurodegenerative disease cases (e.g., Alzheimer’s disease) in advanced countries. Therefore, there is a fertile field for neuroprotective approaches to address this problem. A useful strategy to protect the membrane integrity of cells and reduce inflammatory processes. In this context, the neurons represent particularly vulnerable cells. Thus, a protection strategy should include their membrane preservation and improved anti-inflammatory processes. The contribution of phospholipid derivatives to this issue is crucial and many articles evidence their role in both health and disease. On the other hand, some lipids containing choline actively participate to increase the choline levels in the nervous system. It is acknowledged that the cholinergic system plays a pivotal role both in the central and in the peripheral nervous system. Neurons cannot synthesize choline, which is provided by the diet. The reuptake of ACh and its hydrolysis represent the principal source of choline. Therefore, to cover choline needs, choline-containing lipids may be used. There are different works which demonstrate their neuroprotective features This review article analyzes phospholipid and lipid derivatives that through different mechanisms are involved in these protective processes, although, sometimes the same molecules may behave as neurotoxic elements, therefore, their protective machinery should be detailed better.
Structural Architectural Features of Cyclodextrin Oligoesters Revealed by Fragmentation Mass Spectrometry Analysis
Authors: Peptu Cristian , Danchenko Maksym , Škultéty Ľudovít , Mosnáček Jaroslav
Published: September 2018

Cyclodextrins (CDs) were used in the present study for the ring-opening oligomerization (ROO) of l-lactide (LA) in order to synthesize biodegradable products with possible applications in pharmaceutical and medical fields. The practical importance of ROO reactions may reside in the possibility of synthesizing novel CD derivatives with high purity due to the dual role played by CDs, the role of the initiator through the hydroxylic groups, and the role of the catalyst by monomer inclusion in the CD cavity. The analyzed compounds were CDs modified with oligolactides obtained through ROO reactions of l-lactide in dimethylformamide. The resulting CD isomeric mixtures were investigated using classical characterization techniques such as gel permeation chromatography and nuclear magnetic resonance. Moreover, advanced mass spectrometry (MS) techniques were employed for the determination of the average number of monomer units attached to the cyclodextrin and the architecture of the derivatives (if the monomer units were attached as a single chain or as multiple chains). Thus, fragmentation studies effectuated on two different instruments (ESI Q-TOF and MALDI TOF) allowed us to correlate the size of the oligolactide chains attached to the CD with the observed fragmentation patterns.
Longitudinal Variation of Amino Acid Levels in Human Milk and Their Associations with Infant Gender
Authors: Van Sadelhoff Joris H. J. , Van de Heijning Bert J. M. , Stahl Bernd , Amodio Sonia , Rings Edmond H. H. M. , Mearin M. Luisa , Garssen Johan , Hartog Anita
Published: September 2018

It is discussed that specific amino acids (AAs) have functional roles in early life. Understanding the AA composition in human milk (HM) during lactation assists in specifying these roles. To this end we assessed the levels of free AAs (FAAs), total AAs (free and bound, TAAs) and protein levels in HM in the first 6 months of lactation, and evaluated possible associations with infant gender. HM samples of 25 healthy Dutch mothers participating in the PreventCD study were collected monthly during the first 6 months of lactation. Of the participating mothers, 12 gave birth to a boy and 13 gave birth to a girl. Analyses of the HM samples revealed that levels of free glutamate, glutamine, aspartate, glycine, and serine significantly increased during months 1–3 of lactation, both in absolute sense and relative to TAA levels. Evaluation of gender differences by mixed model analyses revealed an association between female infant gender and higher protein content (p = 0.0465) and TAA content (p = 0.0362) in HM during the first 3 months of lactation. Furthermore, there was a tendency for an association of male infant gender with higher levels of free glutamine (p = 0.0948) in HM during the first 3 months of lactation. These results show that FAA, TAA and protein levels in HM display a time-specific occurrence during lactation. Moreover, although confirmation is necessary in view of the small sample size, this study indicates that the AA composition in HM shows differential effects of the infant’s sex.
DOX-Vit D, a Novel Doxorubicin Delivery Approach, Inhibits Human Osteosarcoma Cell Proliferation by Inducing Apoptosis While Inhibiting Akt and mTOR Signaling Pathways
Authors: Maayah Zaid H. , Zhang Ti , Forrest Marcus Laird , Alrushaid Samaa , Doschak Michael R. , Davies Neal M. , El-Kadi Ayman O. S.
Published: September 2018

Doxorubicin (DOX) is a very potent and effective anticancer agent. However, the effectiveness of DOX in osteosarcoma is usually limited by the acquired drug resistance. Recently, Vitamin D (Vit-D) was shown to suppress the growth of many human cancer cells. Taken together, we synthesized DOX-Vit D by conjugating Vit-D to DOX in order to increase the delivery of DOX into cancer cells and mitigate the chemoresistance associated with DOX. For this purpose, MG63 cells were treated with 10 µM DOX or DOX-Vit D for 24 h. Thereafter, MTT, real-time PCR and western blot analysis were used to determine cell proliferation, genes and proteins expression, respectively. Our results showed that DOX-Vit D, but not DOX, significantly elicited an apoptotic signal in MG63 cells as evidenced by induction of death receptor, Caspase-3 and BCLxs genes. Mechanistically, the DOX-Vit D-induced apoptogens were credited to the activation of p-JNK and p-p38 signaling pathway and the inhibition of proliferative proteins, p-Akt and p-mTOR. Our findings propose that DOX-Vit D suppressed the growth of MG63 cells by inducing apoptosis while inhibiting cell survival and proliferative signaling pathways. DOX-Vit D may serve as a novel drug delivery approach to potentiate the delivery of DOX into cancer cells.
Novel Biobased Polyamide 410/Polyamide 6/CNT Nanocomposites
Authors: Otaegi Itziar , Aramburu Nora , Müller Alejandro J. , Guerrica-Echevarría Gonzalo
Published: September 2018

Biobased polyamide 410 (PA410)/multiwall carbon nanotube (CNT) nanocomposites (NCs) were obtained by melt-mixing in a twin screw extruder a Polyamide 6 (PA6)-based masterbatch (with 15 wt % CNT content) with neat PA410. Directly mixed PA410/CNT NCs were also obtained for comparison purposes. Transmision Electronic Microscopy (TEM) observation and conductivity measurements demonstrated that a good dispersion of CNTs was obtained, which was probably induced by the full miscibility between PA410 and PA6 (in the concentration range employed here), as ascertained by Differential Scanning Calorimetry (DSC) tests. As a result, the PA410/PA6/CNT NCs showed superior mechanical behaviour (≈10% Young’s modulus increase with a 4 wt % CNT content) than the binary PA410/CNT NCs (≈5% Young’s modulus increase with a 6 wt % CNT content), as well as superior electrical behaviour, with maximum conductivity values of approximately three orders of magnitude higher than in the binary PA410/CNT system, and lower percolation threshold values (0.65 wt % CNT content vs. 3.98 wt % CNT). The good dispersion and enhanced mechanical and electrical properties of these novel biobased nanocomposites, broadens their potential applications, such as electrical and electronics (E&E) or automotive industries.
Mass Transfer in Multiphasic Gas/Liquid/Liquid Systems. KLa Determination Using the Effectiveness-Number of Transfer Unit Method
Authors: Dumont Éric
Published: September 2018

The Effectiveness-Number of Transfer Unit method (ε-NTU method) was applied to determine the overall mass transfer coefficient, KLa, of operating gas-liquid absorbers treating Volatile Organic Compounds (VOCs). This method requires the knowledge of the operating conditions (gas flow rate, QG; liquid flow rate, QL; scrubber volume V), the measurement of gaseous concentrations at the inlet, CGin, and at the outlet, CGout, of the contactor (in order to determine the effectiveness of the absorber ε) and the calculation of the Henry coefficient of the VOC between the gas and the liquid phases (HVOC). Coupled with the “equivalent absorption capacity” concept, the ε-NTU method was used to determine KLa of absorbers contacting a gas and a mixture of water and a Non Aqueous Phase, successfully. The method, validated from literature data for configurations countercurrent scrubbers and stirred tank reactors, could be used to simply determine the overall mass transfer coefficient of systems for which the standard KLa determination methods still remain non-reliable or inaccurate (viscous solvents, mixture of immiscible liquids, fermentation broths…).
Investigations on the Coregistration of Sentinel-1 TOPS with the Conventional Cross-Correlation Technique
Authors: Qin Yuxiao , Perissin Daniele , Bai Jing
Published: September 2018

In Sentinel-1 TOPS mode, the antenna sweeps in the azimuth direction for the purpose of illuminating the targets with the entire azimuth antenna pattern (AAP). This azimuth sweeping introduces an extra high-frequency Doppler term into the impulse response function (IRF), which poses a more strict coregistration accuracy for the interferometric purpose. A 1/1000 pixel coregistration accuracy is required for the interferometric phase error to be negligible, and the enhanced spectral diversity (ESD) method is applied for achieving such accuracy. However, since ESD derives miscoregistration from cross-interferometric phase, and phase is always wrapped to [ − π , π ) , an initial coregistration method with enough accuracy is required to resolve the phase ambiguity in ESD. The mainstream for initial coregistration that meets this requirement is the geometrical approach, which accuracy mainly depends on the accuracy of orbits. In this article, the authors propose to investigate the feasibility of using the conventional coregistration approach, namely the cross-correlation-and-rigid-transformation, as the initial coregistration method. The aim is to quantify the coregistration accuracy for cross-correlation-and-rigid-transformation using the Cramér-Rao lower bound (CRLB) and determine whether this method could eventually help to resolve the phase ambiguities of ESD. In addition, we studied the feasibility and robustness of the cross-correlation plus ESD under different conditions. For validation, we checked whether the cross-correlation plus ESD approach could reach the same coregistration accuracy as geometrical plus ESD approach. In general, for large areas with enough coherence and little topography variance, the cross-correlation method could be used as an alternative to the geometrical approach. The interferogram from the two different approaches (with ESD applied afterward) shows a negligible difference under such circumstances.
Air Maidans, Can It Be?
Authors: Correia Zeynep Ceren Henriques
Published: September 2018

Airports are located at the core of the production process, but can they also be where the “revolutionary subject” is hidden? We know what airports stand for nowadays, but have we pushed for what they could possibly stand for? Can airports, as a form of urban technology, be reimagined beyond their current roles of a “space technology nexus” driving capital movement? Can we imagine, idealize, and locate them somewhere else in a period dominated by the economy of time, where speed and accessibility matter the most? In this framework, this provocative essay aims to frame airports as a protest and public expression venue. Drawing inspiration from recent examples, such as the Stansted Airport protests in the UK, the Occupy Airports protests that occurred all around the United States, and touching upon the divergent example of Turkey’s 15th of July night protests in 2016, I provide a glimpse of an alternative prospect for this key urban infrastructure.
Foreign Monitoring and Audit Quality: Evidence from Korea
Authors: Lee Sang Cheol , Rhee Mooweon , Yoon Jongchul
Published: September 2018

This study investigates the effects of both foreign majority shareholders and foreign investors’ participation in the board of directors on audit quality, as reflected by auditor size and audit fees. In addition, the study examines the moderating effect of an agency problem on the relationship between foreign investors and the monitoring of audit quality. Using 1574 non-financial firm-year observations listed on the Korea Stock Exchange from 2000 to 2003, we find that the presence of foreign investors such as foreign block shareholders and foreign outside directors increases audit quality. At the same time, the monitoring role of foreign block shareholders is more powerful than that of foreign external directors. Moreover, the foreign block shareholders in professional management-controlled firms exert a more profound influence on audit quality than do those in owner-controlled ones. These test results imply that foreign investors with independence, expertise, and monitoring incentives could play an important role in improving the corporate governance system in Korea, which in turn would not only enhance firm value, but also strengthen the sustainability of Korean companies.
Using Information on Settlement Patterns to Improve the Spatial Distribution of Population in Coastal Impact Assessments
Authors: Merkens Jan-Ludolf , Vafeidis Athanasios
Published: September 2018

Broad-scale impact and vulnerability assessments are essential for informing decisions on long-term adaptation planning at the national, regional, or global level. These assessments rely on population data for quantifying exposure to different types of hazards. Existing population datasets covering the entire globe at resolutions of 2.5 degrees to 30 arc-seconds are based on information available at administrative-unit level and implicitly assume uniform population densities within these units. This assumption can lead to errors in impact assessments and particularly in coastal areas that are densely populated. This study proposes and compares simple approaches to regionalize population within administrative units in the German Baltic Sea region using solely information on urban extent from the Global Urban Footprint (GUF). Our results show that approaches using GUF can reduce the error in predicting population totals of municipalities by factor 2 to 3. When assessing exposed population, we find that the assumption of uniform population densities leads to an overestimation of 120% to 140%. Using GUF to regionalise population within administrative units reduce these errors by up to 50%. Our results suggest that the proposed simple modeling approaches can result in significantly improved distribution of population within administrative units and substantially improve the results of exposure analyses.
Engineering Gain-of-Function Analogues of the Spider Venom Peptide HNTX-I, A Potent Blocker of the hNaV1.7 Sodium Channel
Authors: Zhang Yunxiao , Yang Qiuchu , Zhang Qingfeng , Peng Dezheng , Chen Minzhi , Liang Songping , Zhou Xi , Liu Zhonghua
Published: September 2018

Pain is a medical condition that interferes with normal human life and work and reduces human well-being worldwide. Human voltage-gated sodium channel NaV1.7 (hNaV1.7) is a compelling target that plays a key role in human pain signaling. The 33-residue peptide µ-TRTX-Hhn2b (HNTX-I), a member of NaV-targeting spider toxin (NaSpTx) family 1, has shown negligible activity on mammalian voltage-gated sodium channels (VGSCs), including the hNaV1.7 channel. We engineered analogues of HNTX-I based on sequence conservation in NaSpTx family 1. Substitution of Asn for Ser at position 23 or Asp for His at position 26 conferred potent activity against hNaV1.7. Moreover, multiple site mutations combined together afforded improvements in potency. Ultimately, we generated an analogue E1G–N23S–D26H–L32W with >300-fold improved potency compared with wild-type HNTX-I on hNaV1.7 (IC50 0.036 ± 0.007 µM). Structural simulation suggested that the charged surface and the hydrophobic surface of the modified peptide are responsible for binding affinity to the hNaV1.7 channel, while variable residues may determine pharmacological specificity. Therefore, this study provides a profile for drug design targeting the hNaV1.7 channel.
Reuse Choice, Flood Risk and Resilience, and Characteristics of Counties with Brownfield Cleanups
Authors: Carroll Ann M. M. , Kanarek Norma F.
Published: September 2018

Limited research has examined brownfields clean-up, reuse choice and associations with flood risk or resilience. This cross-sectional analysis examines counties with U.S. Environmental Protection Agency (EPA) funded brownfield cleanups initiated from 2005 through 2009 and assesses the county-level relationship of green reuse with flood risk while accounting for county factors of resources, environmental stressors, race and ethnicity, location, and structural characteristics, as modified from the Gee and Payne-Sturges conceptual model of community environmental health. Flood plain designation predicted a three-fold odds of green reuse alone (OR = 2.96 [95% CI, 1.31–6.66]) and green with other reuses (OR = 2.88 [95% CI, 1.07–7.75]). Green reuse alone was influenced negatively when a county had an eastern or western US location or a larger proportion of population aged 5–24 and positively when population education levels were higher. Among counties with green and other reuse, low education was predictive. Conceptually, decisions for green reuse alone were driven by resources and location while decisions for green and other reuse were driven by resources, location and environmental stressors.
Improved Modelling of a Nonlinear Parametrically Excited System with Electromagnetic Excitation
Authors: Zaghari Bahareh , Rustighi Emiliano , Ghandchi Tehrani Maryam
Published: September 2018

In this work, the nonlinear behaviour of a parametrically excited system with electromagnetic excitation is accurately modelled, predicted and experimentally investigated. The equations of motion include both the electromechanical coupling factor and the electromechanical damping. Unlike previous studies where only linear time-varying stiffness due to electromagnetic forces was presented, in this paper the effect of the induced current is studied. As a consequence, nonlinear parameters such as electromechanical damping, cubic stiffness and cubic parametric stiffness have been included in the model. These parameters are also observed experimentally by controlling the direct current (DC) and alternating current (AC) passed through the electromagnets. In fact, the proposed apparatus allows to control both linear and nonlinear stiffnesses and the independent effect of each parameter on the response is presented. In particular the effect of the cubic parametric stiffness on the parametric resonance amplitudes and the influence of cubic stiffness on the frequency bandwidth of the parametric resonance are shown. This model improves the prediction of parametric resonance, frequency bandwidth, and the response amplitude of parametrically excited systems and it may lead to refined design of electromagnetic actuators, filters, amplifiers, vibration energy harvesters, and magnetic bearings.
Supermassive Black Holes with High Accretion Rates in Active Galactic Nuclei. VII. Reconstruction of Velocity-delay Maps by the Maximum Entropy Method
Authors: Xiao Ming , Du Pu , Horne Keith , Hu Chen , Li Yan-Rong , Huang Ying-Ke , Lu Kai-Xing , Qiu Jie , Wang Fang , Bai Jin-Ming , Bian Wei-Hao , Ho Luis C. , Yuan Ye-Fei , Wang Jian-Min ,   (SEAMBH collaboration)
Published: September 2018

As one of a series of papers reporting on a large reverberation mapping campaign, we apply the maximum entropy method (MEM) to nine narrow-line Seyfert 1 galaxies with super-Eddington accretion rates observed during 2012–2013 for the velocity-delay maps of their Hβ and Hγ emission lines. The maps of six objects are reliably reconstructed using MEM. The maps of Hβ and Hγ emission lines of Mrk 335 indicate that the gas of its broad-line region (BLR) is infalling. For Mrk 142, its Hβ and Hγ lines show signatures of outflow. The Hβ and Hγ maps of Mrk 1044 demonstrate complex kinematics—a virialized motion accompanied by an outflow signature, and the Hβ map of IRAS F12397+3333 is consistent with a disk or a spherical shell. The Hβ maps of Mrk 486 and MCG +06-26-012 suggest the presence of inflow and outflow, respectively. These super-Eddington accretors show diverse geometry and kinematics. Brief discussions of their BLRs are provided for each individual object.
Texas Spectroscopic Search for Lyα Emission at the End of Reionization I. Constraining the Lyα Equivalent-width Distribution at 6.0 < z < 7.0
Authors: Jung Intae , Finkelstein Steven L. , Livermore Rachael C. , Dickinson Mark , Larson Rebecca L. , Papovich Casey , Song Mimi , Tilvi Vithal , Wold Isak
Published: September 2018

The distribution of Lyα emission is a presently accessible method for studying the state of the intergalactic medium (IGM) into the reionization era. We carried out deep spectroscopic observations in order to search for Lyα emission from galaxies with photometric redshifts z = 5.5–8.3 selected from the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey. Utilizing data from the Keck/DEIMOS spectrograph, we explore a wavelength coverage of Lyα emission at z ∼ 5–7 with 4 nights of spectroscopic observations for 118 galaxies, detecting five emission lines with ∼5σ significance: three in the GOODS-N and two in the GOODS-S fields. We constrain the equivalent-width (EW) distribution of Lyα emission by comparing the number of detected objects with the expected number constructed from detailed simulations of mock emission lines that account for the observational conditions (e.g., exposure time, wavelength coverage, and sky emission) and galaxy photometric redshift probability distribution functions. The Lyα EW distribution is well described by an exponential form, dN/dEW ∝ exp(−EW/W
0), characterized by the e-folding scale (W
0) of ∼60–100 Å at 0.3 < z < 6. By contrast, our measure of the Lyα EW distribution at 6.0 < z < 7.0 rejects a Lyα EW distribution with W
0 > 36.4 Å (125.3 Å) at 1σ (2σ) significance. This provides additional evidence that the EW distribution of Lyα declines at z > 6, suggesting an increasing fraction of neutral hydrogen in the IGM at that epoch.
Evidence of Jet–Clump Interaction: A Flip of the Radio Jet Head of 3C 84
Authors: Kino M. , Wajima K. , Kawakatu N. , Nagai H. , Orienti M. , Giovannini G. , Hada K. , Niinuma K. , Giroletti M.
Published: September 2018

Radio jets in active galaxies have been expected to interact with circumnuclear environments in their early phase evolutions. By performing the multi-epoch monitoring observation with the KVN and VERA Array at 43 GHz, we investigate the kinematics of the notable newborn bright component C3 located at the tip of the recurrent jet of 3C 84. During 2015 August–September, we discover the flip of C3 and the amount of the flip is about 0.4 mas in angular scale, which corresponds to 0.14 parsec in physical scale. After the flip of C3, it wobbled at the same location for a few months and then it restarted to propagate toward the southern direction. The flux density of C3 coherently showed the monotonic increase during the observation period. The flip is in good agreement with hydrodynamical simulations of jets in clumpy ambient medium. We estimate the number density of the putative clump based on the momentum balance between the jet thrust and the ram pressure from the clump and it is about 103–5 cm−3. We briefly discuss possible origins of the clump.
Electromagnetic Emission from Blitzars and Its Impact on Non-repeating Fast Radio Bursts
Authors: Most Elias R. , Nathanail Antonios , Rezzolla Luciano
Published: September 2018

It has been suggested that a non-repeating fast radio burst (FRB) represents the final signal of a magnetized neutron star collapsing to a black hole. In this model, a supramassive neutron star supported by rapid rotation, will collapse to a black hole several thousand to million years after its birth, as a result of spin-down. The collapse violently snaps the magnetic field lines anchored on the stellar surface, thus producing an electromagnetic pulse that will propagate outward and accelerate electrons, thus producing a massive radio burst, i.e., a “blitzar.” We present a systematic study of the gravitational collapse of rotating and magnetized neutron stars, with special attention to far-field evolution at late times after the collapse. By considering a series of neutron stars with rotation ranging from zero to millisecond periods and different magnetic-field strengths, we show that the blitzar emission is very robust and always characterized by a series sub-millisecond pulses decaying exponentially in amplitude. The luminosity and energy released when the magnetosphere is destroyed are well-reproduced by a simple expression in terms of the stellar magnetic field and radius. Finally, we assess the occurrence of pair production during a blitzar scenario. We conclude that, for typical magnetic-field strengths of 1012 G and spin frequencies of a few Hz, pair production is suppressed. Overall, the very good match between the results of the simulations and the luminosities normally observed for FRBs lends credibility to the blitzar model as a simple yet plausible explanation for the phenomenology of non-repeating FRBs.
Modeling Photoionized Turbulent Material in the Circumgalactic Medium
Authors: Buie II Edward , Gray William J. , Scannapieco Evan
Published: September 2018

The circumgalactic medium (CGM) of nearby star-forming galaxies shows clear indications of O vi absorption accompanied by little to no N v absorption. This unusual spectral signature, accompanied by absorption from lower ionization state species whose columns vary by orders of magnitude along  different sight lines, indicates that the CGM must be viewed as a dynamic, multiphase medium, such as occurs in the presence of turbulence. To explore this possibility, we carry out a series of chemodynamical simulations of a isotropic turbulent media, using the MAIHEM package. The simulations assume a metallicity of 0.3 Z
⊙ and a redshift zero metagalatic UV background, and they track ionizations, recombinations, and species-by-species radiative cooling for a wide range of elements. We find that turbulence with a one-dimensional (1D) velocity dispersion of σ
1D ≈ 60 km s−1 replicates many of the observed features within the CGM, such as clumping of low ionization-state ions and the existence of O vi at moderate ionization parameters. However, unlike observations, N v often arises in our simulations with derived column densities of a similar magnitude to those of O vi. While higher values of σ
1D lead to a thermal runaway in our isotropic simulations, this would not be the case in stratified media, and thus we speculate that more complex models of the turbulence may well match the absence of N v in the CGM of star-forming galaxies.
Observations on the Magnetic Disconnections of a Magnetic Cloud from the Sun through Magnetic Reconnection
Authors: Feng H. Q. , Wang J. M. , Zhao G. Q. , Zhao Y.
Published: September 2018

Most coronal mass ejections (CMEs) originally exhibit closed magnetic flux rope (MFR) structures near the Sun. Moreover, the amount of magnetic field magnitude in the heliosphere can continually increase when CMEs propagate from the Sun to interplanetary space. To solve the problem of increased magnetic field magnitude, the closed field lines of MFRs should be opened and disconnected through magnetic reconnections. Here, we report a magnetic cloud (MC) associated with a magnetic reconnection exhaust measured by Wind over the period of 2001 October 31 to November 1. Observations of unidirectional suprathermal electron strahls revealed that part of the field lines before the rear boundary of the MC was opened. The magnetic reconnection event was disconnecting the opened field lines of the MC by merging with open field lines after the MC. These observations indicated that MFRs could be opened or disconnected in no particular order.
The Orbital Architecture and Debris Disks of the HR 8799 Planetary System
Authors: Goździewski Krzysztof , Migaszewski Cezary
Published: September 2018

The HR 8799 planetary system with four ≃10 m
Jup planets in wide orbits up to ≃70 au and orbital periods up to 500 yr has been detected with direct imaging. Its intriguing orbital architecture is not yet fully resolved due to time-limited astrometry covering only ≃20 yr. Earlier, we constructed a heuristic model of the system based on rapid, convergent migration of the planets. Here we develop a better-structured and CPU-efficient variant of this model. With the updated approach, we reanalyzed the self-consistent, homogeneous astrometric data set in Konopacky et al. The best-fitting configuration agrees with our earlier findings. The HR 8799 planets are likely involved in a dynamically robust Laplace 8e:4d:2c:1b resonance chain. Hypothetical planets with masses below the current detection limit of 0.1–3 m
Jup within the observed inner or beyond the outer orbit, respectively, do not influence the long-term stability of the system. We predict the positions of such nondetected objects. The long-term stable orbital model of the observed planets helps to simulate the dynamical structure of debris disks in the system. A CPU-efficient fast indicator technique makes it possible to reveal their complex, resonant shape in 106 particles scale. We examine the inner edge of the outer disk detected between 90 and 145 au. We also reconstruct the outer disk, assuming that it has been influenced by the convergent migration of the planets. A complex shape of the disk strongly depends on various dynamical factors, like orbits and masses of nondetected planets. It may be highly noncircular, and its models are yet nonunique regarding both observational constraints and its origin.
L’embellissement de la basilique du Pilar de Saragosse à l’épreuve du public
Authors: Jiméno Frédéric
Published: September 2018

Durant la seconde moitié du 18 e siècle, le chantier d’embellissement de la basilique du Pilar à Saragosse témoigne de la volonté des autorités de faire de cet édifice un écrin des nouvelles tendances artistiques. Les artistes sélectionnés offrent au public un modèle qui deviendra la norme et sera copié et interprété par les artistes locaux. Le Pilar devient alors un lieu de l’art, symbole d’une renaissance politique et artistique, ce qui explique la vive réaction du public envers Goya qui participe au chantier en 1781.
« Ordinairement dans son atelier… » L’atelier du sculpteur Jean-Baptiste Lemoyne (1704-1778)
Authors: Champy-Vinas Cécilie
Published: September 2018

L’atelier du sculpteur Jean-Baptiste Lemoyne (1704-1778), portraitiste favori du roi Louis XV, a été totalement dispersé au cours des 18 e et 19 e siècles. Cependant trois inventaires inédits permettent d’en reconstituer précisément la topographie et documentent les processus de création du sculpteur. L’analyse de ces inventaires, complétée par des sources littéraires et iconographiques, montre ainsi que l’atelier du sculpteur est certes et avant tout un lieu de travail, collectif et organisé, mais également un lieu de sociabilité qui sert à promouvoir le renom de l’artiste.
« Sous un grand bocal, une… fille charmante » le modèle du cabinet de curiosités dans deux Nuits de Paris
Authors: Muscat Morgane
Published: September 2018

Les lieux de l’art semblent absents du parcours des Nuits de Paris  ; à l’exception du cabinet de curiosités qui apparaît notamment dans les 5 e et 91 e nuits, où le Spectateur découvre, exposées, une fille embaumée et une autre reproduite fidèlement en cire. Cette étude s’attache à comprendre l’utilisation du modèle du cabinet de curiosités, qui permet une exposition morbide du corps féminin mais également l’affirmation d’un parti pris esthétique.