bluuebunny/crossref_metadata_2025 huggingface dataset:
Application of a High-Power Reversible Converter in a Hybrid Traction Power Supply System
Authors: Zhang Gang , Qian Jianglin , Zhang Xinyu
Published: March 2017

A high-power reversible converter can achieve a variety of functions, such as recovering regenerative braking energy, expanding traction power capacity, and improving an alternating current (AC) grid power factor. A new hybrid traction power supply scheme, which consists of a high-power reversible converter and two 12-pulse diode rectifiers, is proposed. A droop control method based on load current feed-forward is adopted to realize the load distribution between the reversible converter and the existing 12-pulse diode rectifiers. The direct current (DC) short-circuit characteristics of the reversible converter is studied, then the relationship between the peak fault current and the circuit parameters is obtained from theoretical calculations and validated by computer simulation. The first two sets of 2 MW reversible converters have been successfully applied in Beijing Metro Line 10, the proposed hybrid application scheme and coordinated control strategy are verified, and 11.15% of average energy-savings is reached.
Construction of Compact Finite Difference Schemes by Classic Differential Quadrature
Authors: Wang Fangzong , Pan Mingshuai , Wang Yong
Published: March 2017

Using classic differential quadrature formulae and uniform grids, this paper systematically constructs a variety of high-order finite difference schemes, and some of these schemes are consistent with the so-called boundary value methods. The derived difference schemes enjoy the same stability and accuracy properties with correspondent differential quadrature methods but have a simpler form of calculation; thus, they can be seen as a compact format of classic differential quadrature methods. Through systematic Fourier stability analysis, the characteristics such as the dissipation, dispersion and resolution of the different schemes were studied and compared.
Physics of Prestall Propagating Disturbances in Axial Compressors and Their Potential as a Stall Warning Indicator
Authors: Eck Mario , Geist Silvio , Peitsch Dieter
Published: March 2017

Axial compressors in aero engines are prone to suffering a breakdown of orderly flow when operating at the peak of the pressure rise characteristic. The damaging potential of separated flows is why a safe distance has to be left between every possible operating point and an operating point at which stall occurs. During earlier investigations of stall inception mechanisms, a new type of prestall instability has been found. In this study, it could be demonstrated that the prestall instability characterised by discrete flow disturbances can be clearly assigned to the subject of “Rotating Instabilities”. Propagating disturbances are responsible for the rise in blade passing irregularity. If the mass flow is reduced successively, the level of irregularity increases until the prestall condition devolves into rotating stall. The primary objective of the current work is to highlight the basic physics behind these prestall disturbances by complementary experimental and numerical investigations. Before reaching the peak of the pressure rise characteristic flow, disturbances appear as small vortex tubes with one end attached to the casing and the other attached to the suction surface of the rotor blade. These vortex structures arise when the entire tip region is affected by blockage and at the same time the critical rotor incidence is not exceeded in this flow regime. Furthermore, a new stall indicator was developed by applying statistical methods to the unsteady pressure signal measured over the rotor blade tips, thus granting a better control of the safety margin.
Opposite Trends in Light Rain Days over Western and Eastern China from 1960 to 2014
Authors: Song Shikai , Jing Changqing , Hu Zengyun
Published: March 2017

In this work, we examined spatial and temporal trends for light rain days based on daily precipitation measurements, obtained from 1960 to 2014, from 590 meteorological stations in China. For the analyzed time interval, light rain days over eastern China were determined to decrease by 0.23 days·year−1. In western China, they increased by 0.3 days·year−1. To detect underlying causes for changes in light rain days, lower-tropospheric relative humidity was set as a proxy for light rain days. We then calculated the respective impacts of lower-tropospheric temperature and specific humidity on changes in light rain days. A comparison of the contributions of temperature and specific humidity resulted in the identification of the main cause of changes. Our results indicated that increases in lower-tropospheric temperatures reduced light rain days over the entire country, while variations in specific humidity dominated regional differences for light rain day trends.
Dendrimer-Stabilized Ru Nanoparticles Immobilized in Organo-Silica Materials for Hydrogenation of Phenols
Authors: Karakhanov Eduard , Maximov Anton , Zolotukhina Anna , Mamadli Adila , Vutolkina Anna , Ivanov Andrey
Published: March 2017

New hybrid catalysts based on Ru nanoparticles, encapsulated into poly(propylene imine dendrimers), immobilized into silica pores, were synthesized and examined for the hydrogenation of alkyl-substituted phenols. The corresponding alkyl-substituted cyclohexanols were presented as the major reaction products, while incomplete hydrogenation products appeared to be minor. A competition between the sterical factors of dendrimer-containing carriers and the electronic factors of substrate substituents influenced the hydrogenation rate of the alkyl-substituted phenols. The carrier structure was found to have a significant influence on both the physical and chemical properties of the catalysts and their hydrogenation activity. The synthesized hybrid catalysts appeared to be stable after recycling and could be re-used several times without significant loss of activity.
Fluctuation-Driven Transport in Biological Nanopores. A 3D Poisson–Nernst–Planck Study
Authors: Aguilella-Arzo Marcel , Queralt-Martín María , Lopez María-Lidón , Alcaraz Antonio
Published: March 2017

Living systems display a variety of situations in which non-equilibrium fluctuations couple to certain protein functions yielding astonishing results. Here we study the bacterial channel OmpF under conditions similar to those met in vivo, where acidic resistance mechanisms are known to yield oscillations in the electric potential across the cell membrane. We use a three-dimensional structure-based theoretical approach to assess the possibility of obtaining fluctuation-driven transport. Our calculations show that remarkably high voltages would be necessary to observe the actual transport of ions against their concentration gradient. The reasons behind this are the mild selectivity of this bacterial pore and the relatively low efficiencies of the oscillating signals characteristic of membrane cells (random telegraph noise and thermal noise).
Near Wellbore Hydraulic Fracture Propagation from Perforations in Tight Rocks: The Roles of Fracturing Fluid Viscosity and Injection Rate
Authors: Fallahzadeh Seyed , Hossain Md , James Cornwell Ashton , Rasouli Vamegh
Published: March 2017

Hydraulic fracture initiation and near wellbore propagation is governed by complex failure mechanisms, especially in cased perforated wellbores. Various parameters affect such mechanisms, including fracturing fluid viscosity and injection rate. In this study, three different fracturing fluids with viscosities ranging from 20 to 600 Pa.s were used to investigate the effects of varying fracturing fluid viscosities and fluid injection rates on the fracturing mechanisms. Hydraulic fracturing tests were conducted in cased perforated boreholes made in tight 150 mm synthetic cubic samples. A true tri-axial stress cell was used to simulate real far field stress conditions. In addition, dimensional analyses were performed to correspond the results of lab experiments to field-scale operations. The results indicated that by increasing the fracturing fluid viscosity and injection rate, the fracturing energy increased, and consequently, higher fracturing pressures were observed. However, when the fracturing energy was transferred to a borehole at a faster rate, the fracture initiation angle also increased. This resulted in more curved fracture planes. Accordingly, a new parameter, called fracturing power, was introduced to relate fracture geometry to fluid viscosity and injection rate. Furthermore, it was observed that the presence of casing in the wellbore impacted the stress distribution around the casing in such a way that the fracture propagation deviated from the wellbore vicinity.
The Deployment of Low Carbon Technologies in Energy Intensive Industries: A Macroeconomic Analysis for Europe, China and India
Authors: Nabernegg Stefan , Bednar-Friedl Birgit , Wagner Fabian , Schinko Thomas , Cofala Janusz , Clement Yadira Mori
Published: March 2017

Industrial processes currently contribute 40% to global CO2 emissions and therefore substantial increases in industrial energy efficiency are required for reaching the 2 °C target. We assess the macroeconomic effects of deploying low carbon technologies in six energy intensive industrial sectors (Petroleum, Iron and Steel, Non-metallic Minerals, Paper and Pulp, Chemicals, and Electricity) in Europe, China and India in 2030. By combining the GAINS technology model with a macroeconomic computable general equilibrium model, we find that output in energy intensive industries declines in Europe by 6% in total, while output increases in China by 11% and in India by 13%. The opposite output effects emerge because low carbon technologies lead to cost savings in China and India but not in Europe. Consequently, the competitiveness of energy intensive industries is improved in China and India relative to Europe, leading to higher exports to Europe. In all regions, the decarbonization of electricity plays the dominant role for mitigation. We find a rebound effect in China and India, in the size of 42% and 34% CO2 reduction, respectively, but not in Europe. Our results indicate that the range of considered low-carbon technology options is not competitive in the European industrial sectors. To foster breakthrough low carbon technologies and maintain industrial competitiveness, targeted technology policy is therefore needed to supplement carbon pricing.
A Top-Down Spatially Resolved Electrical Load Model
Authors: Robinius Martin , Stein Felix ter , Schwane Adrien , Stolten Detlef
Published: March 2017

The increasing deployment of variable renewable energy sources (VRES) is changing the source regime in the electrical energy sector. However, VRES feed-in from wind turbines and photovoltaic systems is dependent on the weather and only partially predictable. As a result, existing energy sector models must be re-evaluated and adjusted as necessary. In long-term forecast models, the expansion of VRES must be taken into account so that future local overloads can be identified and measures taken. This paper focuses on one input factor for electrical energy models: the electrical load. We compare two different types to describe this, namely vertical grid load and total load. For the total load, an approach for a spatially-resolved electrical load model is developed and applied at the municipal level in Germany. This model provides detailed information about the load at a quarterly-hour resolution across 11,268 German municipalities. In municipalities with concentrations of energy-intensive industry, high loads are expected, which our simulation reproduces with a good degree of accuracy. Our results also show that municipalities with energy-intensive industry have a higher simulated electric load than neighboring municipalities that do not host energy-intensive industries. The underlying data was extracted from publically accessible sources and therefore the methodology introduced is also applicable to other countries.
Highly-Efficient and Compact 6 kW/4 × 125 kHz Interleaved DC-DC Boost Converter with SiC Devices and Low-Capacitive Inductors
Authors: Zdanowski Mariusz , Rabkowski Jacek , Barlik Roman
Published: March 2017

This paper describes a four-leg interleaved DC-DC boost converter built on the basis of Silicon Carbide (SiC) devices (Metal-Oxide Semiconductor Field-Effect Transistors—MOSFETs and Schottky diodes) and improved, low-capacitive magnetic components. A combination of wide-bandgap semiconductors capable of operating at elevated switching frequencies and an interleaving technique brings substantial benefits, such as a cancellation of the input/output current ripples, a reduction of weight, dimensions and increase of power density. The 4 × 125 kHz DC-DC boost converter characterized by a volume of 0.75 dm3 reaches an efficiency above 98.7% at nominal power of 6 kW. A special effort has been made to develop and test inductors with low parasitic capacitance. It is clearly proven that an improved design has an impact on the converter performance, especially on power losses. Reduction of the power losses is higher than 25% in reference to a standard design of the inductors and the efficiency is in excess of 99%.
A Community Multi-Omics Approach towards the Assessment of Surface Water Quality in an Urban River System
Authors: Beale David , Karpe Avinash , Ahmed Warish , Cook Stephen , Morrison Paul , Staley Christopher , Sadowsky Michael , Palombo Enzo
Published: March 2017

A multi-omics approach was applied to an urban river system (the Brisbane River (BR), Queensland, Australia) in order to investigate surface water quality and characterize the bacterial population with respect to water contaminants. To do this, bacterial metagenomic amplicon-sequencing using Illumina next-generation sequencing (NGS) of the V5–V6 hypervariable regions of the 16S rRNA gene and untargeted community metabolomics using gas chromatography coupled with mass spectrometry (GC-MS) were utilized. The multi-omics data, in combination with fecal indicator bacteria (FIB) counts, trace metal concentrations (by inductively coupled plasma mass spectrometry (ICP-MS)) and in-situ water quality measurements collected from various locations along the BR were then used to assess the health of the river ecosystem. Sites sampled represented the transition from less affected (upstream) to polluted (downstream) environments along the BR. Chemometric analysis of the combined datasets indicated a clear separation between the sampled environments. Burkholderiales and Cyanobacteria were common key factors for differentiation of pristine waters. Increased sugar alcohol and short-chain fatty acid production was observed by Actinomycetales and Rhodospirillaceae that are known to form biofilms in urban polluted and brackish waters. Results from this study indicate that a multi-omics approach enables a deep understanding of the health of an aquatic ecosystem, providing insight into the bacterial diversity present and the metabolic output of the population when exposed to environmental contaminants.
Knowledge, Self-Confidence and Attitudes towards Suicidal Patients at Emergency and Psychiatric Departments: A Randomised Controlled Trial of the Effects of an Educational Poster Campaign
Authors: Van Landschoot Renate , Portzky Gwendolyn , Van Heeringen Kees
Published: March 2017

Educational posters are used to enhance knowledge, attitudes and self-confidence of patients. Little is known on their effectiveness for educating health care professionals. As these professionals may play an important role in suicide prevention, the effects of a poster and accompanying evaluation and triage guide on knowledge, self-confidence and attitudes regarding suicidal thoughts and behaviours, were studied in a multicentre cluster randomised controlled trial, involving staff from 39 emergency and 38 psychiatric departments throughout Flanders (n = 1171). Structured self-report questionnaires assessed the knowledge, confidence and beliefs regarding suicidal behaviour management, and attitudes. Data were analysed through a Solomon four-group design, with random assignment to the different conditions. Baseline scores for knowledge and provider confidence were high. The poster and accompanying evaluation and triage guide did not have an effect on knowledge about suicide and self-confidence in suicidal behaviour management. However, the poster campaign appeared to be beneficial for attitudes towards suicidal patients, but only among staff from mental health departments that were assigned to the un-pretested condition. Given the limited effects of the poster campaign in the studied population with a relatively high baseline knowledge, the evaluation of this poster as part of a multimodal educational programme in a more heterogeneous sample of health care professionals is recommended.
Assessing Crowdsourced POI Quality: Combining Methods Based on Reference Data, History, and Spatial Relations
Authors: Touya Guillaume , Antoniou Vyron , Olteanu-Raimond Ana-Maria , Van Damme Marie-Dominique
Published: March 2017

With the development of location-aware devices and the success and high use of Web 2.0 techniques, citizens are able to act as sensors by contributing geographic information. In this context, data quality is an important aspect that should be taken into account when using this source of data for different purposes. The goal of the paper is to analyze the quality of crowdsourced data and to study its evolution over time. We propose two types of approaches: (1) use the intrinsic characteristics of the crowdsourced datasets; or (2) evaluate crowdsourced Points of Interest (POIs) using external datasets (i.e., authoritative reference or other crowdsourced datasets), and two different methods for each approach. The potential of the combination of these approaches is then demonstrated, to overcome the limitations associated with each individual method. In this paper, we focus on POIs and places coming from the very successful crowdsourcing project: OpenStreetMap. The results show that the proposed approaches are complementary in assessing data quality. The positive results obtained for data matching show that the analysis of data quality through automatic data matching is possible but considerable effort and attention are needed for schema matching given the heterogeneity of OSM and the representation of authoritative datasets. For the features studied, it can be noted that change over time is sometimes due to disagreements between contributors, but in most cases the change improves the quality of the data.
The Adverse Effect of Hypertension in the Treatment of Thyroid Cancer with Multi-Kinase Inhibitors
Authors: Ancker Ole , Wehland Markus , Bauer Johann , Infanger Manfred , Grimm Daniela
Published: March 2017

The treatment of thyroid cancer has promising prospects, mostly through the use of surgical or radioactive iodine therapy. However, some thyroid cancers, such as progressive radioactive iodine-refractory differentiated thyroid carcinoma, are not remediable with conventional types of treatment. In these cases, a treatment regimen with multi-kinase inhibitors is advisable. Unfortunately, clinical trials have shown a large number of patients, treated with multi-kinase inhibitors, being adversely affected by hypertension. This means that treatment of thyroid cancer with multi-kinase inhibitors prolongs progression-free and overall survival of patients, but a large number of patients experience hypertension as an adverse effect of the treatment. Whether the prolonged lifetime is sufficient to develop sequelae from hypertension is unclear, but late-stage cancer patients often have additional diseases, which can be complicated by the presence of hypertension. Since the exact mechanisms of the rise of hypertension in these patients are still unknown, the only available strategy is treating the symptoms. More studies determining the pathogenesis of hypertension as a side effect to cancer treatment as well as outcomes of dose management of cancer drugs are necessary to improve future therapy options for hypertension as an adverse effect to cancer therapy with multi-kinase inhibitors.
Evaluation and Adaptation of a Laboratory-Based cDNA Library Preparation Protocol for Retrospective Sequencing of Archived MicroRNAs from up to 35-Year-Old Clinical FFPE Specimens
Authors: Loudig Olivier , Wang Tao , Ye Kenny , Lin Juan , Wang Yihong , Ramnauth Andrew , Liu Christina , Stark Azadeh , Chitale Dhananjay , Greenlee Robert , Multerer Deborah , Honda Stacey , Daida Yihe , Spencer Feigelson Heather , Glass Andrew , Couch Fergus , Rohan Thomas , Ben-Dov Iddo
Published: March 2017

Formalin-fixed paraffin-embedded (FFPE) specimens, when used in conjunction with patient clinical data history, represent an invaluable resource for molecular studies of cancer. Even though nucleic acids extracted from archived FFPE tissues are degraded, their molecular analysis has become possible. In this study, we optimized a laboratory-based next-generation sequencing barcoded cDNA library preparation protocol for analysis of small RNAs recovered from archived FFPE tissues. Using matched fresh and FFPE specimens, we evaluated the robustness and reproducibility of our optimized approach, as well as its applicability to archived clinical specimens stored for up to 35 years. We then evaluated this cDNA library preparation protocol by performing a miRNA expression analysis of archived breast ductal carcinoma in situ (DCIS) specimens, selected for their relation to the risk of subsequent breast cancer development and obtained from six different institutions. Our analyses identified six miRNAs (miR-29a, miR-221, miR-375, miR-184, miR-363, miR-455-5p) differentially expressed between DCIS lesions from women who subsequently developed an invasive breast cancer (cases) and women who did not develop invasive breast cancer within the same time interval (control). Our thorough evaluation and application of this laboratory-based miRNA sequencing analysis indicates that the preparation of small RNA cDNA libraries can reliably be performed on older, archived, clinically-classified specimens.
A Review on Ubiquitination of Neurotrophin Receptors: Facts and Perspectives
Authors: Sánchez-Sánchez Julia , Arévalo Juan
Published: March 2017

Ubiquitination is a reversible post-translational modification involved in a plethora of different physiological functions. Among the substrates that are ubiquitinated, neurotrophin receptors (TrkA, TrkB, TrkC, and p75NTR) have been studied recently. TrkA is the most studied receptor in terms of its ubiquitination, and different E3 ubiquitin ligases and deubiquitinases have been implicated in its ubiquitination, whereas not much is known about the other neurotrophin receptors aside from their ubiquitination. Additional studies are needed that focus on the ubiquitination of TrkB, TrkC, and p75NTR in order to further understand the role of ubiquitination in their physiological and pathological functions. Here we review what is currently known regarding the ubiquitination of neurotrophin receptors and its physiological and pathological relevance.
Effect of Clozapine on DNA Methylation in Peripheral Leukocytes from Patients with Treatment-Resistant Schizophrenia
Authors: Kinoshita Makoto , Numata Shusuke , Tajima Atsushi , Yamamori Hidenaga , Yasuda Yuka , Fujimoto Michiko , Watanabe Shinya , Umehara Hidehiro , Shimodera Shinji , Nakazawa Takanobu , Kikuchi Masataka , Nakaya Akihiro , Hashimoto Hitoshi , Imoto Issei , Hashimoto Ryota , Ohmori Tetsuro
Published: March 2017

Clozapine is an atypical antipsychotic, that is established as the treatment of choice for treatment-resistant schizophrenia (SCZ). To date, no study investigating comprehensive DNA methylation changes in SCZ patients treated with chronic clozapine has been reported. The purpose of the present study is to reveal the effects of clozapine on DNA methylation in treatment-resistant SCZ. We conducted a genome-wide DNA methylation profiling in peripheral leukocytes (485,764 CpG dinucleotides) from treatment-resistant SCZ patients treated with clozapine (n = 21) in a longitudinal study. Significant changes in DNA methylation were observed at 29,134 sites after one year of treatment with clozapine, and these genes were enriched for “cell substrate adhesion” and “cell matrix adhesion” gene ontology (GO) terms. Furthermore, DNA methylation changes in the CREBBP (CREB binding protein) gene were significantly correlated with the clinical improvements. Our findings provide insights into the action of clozapine in treatment-resistant SCZ.
Information and Symmetry: Adumbrating the Abstract Core of Complex Systems
Authors: Bi Lin , Igamberdiev Abir U. , Marijuán Pedro C.
Published: March 2017

Information and symmetry are essential theoretical concepts that underlie the scientific explanation of a variety of complex systems. In spite of clear-cut developments around both concepts, their intersection is really problematic, either in fields related to mathematics, physics, and chemistry, or even more in those pertaining to biology, neurosciences, and social sciences. The present Special Issue explores recent developments, both theoretical and applied, in most of these disciplines.
Microscopic Analysis of Pigments Extracted from Spalting Fungi
Authors: Vega Gutierrez Sarath , Robinson Sara
Published: March 2017

Pigments that are currently available in the market usually come from synthetic sources, or, if natural, often need mordants to bind to the target substrate. Recent research on the fungal pigment extracts from Scytalidium cuboideum, Scytalidium ganodermophthorum, Chlorociboria aeruginosa, and Chlorociboria aeruginascens have been shown to successfully dye materials, like wood, bamboo, and textiles, however, there is no information about their binding mechanisms. Due to this, a microscopic study was performed to provide information to future manufacturers interested in these pigments. The results of this study show that S. ganodermophthorum and C. aeruginosa form an amorphous layer on substrates, while S. cuboideum forms crystal-like structures. The attachment and morphology indicate that there might be different chemical and physical interactions between the extracted pigments and the materials. This possibility can explain the high resistance of the pigments to UV light and color fastness that makes them competitive against synthetic pigments. These properties make these pigments a viable option for an industry that demands natural pigments with the properties of the synthetic ones.
Can Community Forests Be Compatible With Biodiversity Conservation in Indonesia?
Authors: Boedhihartono Agni
Published: March 2017

Forest lands in Indonesia are classified as state lands and subject to management under agreements allocated by the Ministry of Environment and Forestry. There has been a long-standing tension between the ministry and local communities who argue that they have traditionally managed large areas of forest and should be allowed to continue to do so. A series of recent legal and administrative decisions are now paving the way for the allocation of forests to local communities. There is a hypothesis that the communities will protect the forests against industrial conversion and that they will also conserve biodiversity. This hypothesis needs to be closely examined. Conservation of biodiversity and management for local benefits are two different and potentially conflicting objectives. This paper reviews examples of forests managed by local communities in Indonesia and concludes that there is very limited information available on the conservation of natural biodiversity in these forests. I conclude that more information is needed on the status of biodiversity in community managed forests. When forests are allocated for local management, special measures need to be in place to ensure that biodiversity values are monitored and maintained.
An Updated Review of Ciguatera Fish Poisoning: Clinical, Epidemiological, Environmental, and Public Health Management
Authors: Friedman Melissa , Fernandez Mercedes , Backer Lorraine , Dickey Robert , Bernstein Jeffrey , Schrank Kathleen , Kibler Steven , Stephan Wendy , Gribble Matthew , Bienfang Paul , Bowen Robert , Degrasse Stacey , Flores Quintana Harold , Loeffler Christopher , Weisman Richard , Blythe Donna , Berdalet Elisa , Ayyar Ram , Clarkson-Townsend Danielle , Swajian Karen , Benner Ronald , Brewer Tom , Fleming Lora
Published: March 2017

Ciguatera Fish Poisoning (CFP) is the most frequently reported seafood-toxin illness in the world. It causes substantial human health, social, and economic impacts. The illness produces a complex array of gastrointestinal, neurological and neuropsychological, and cardiovascular symptoms, which may last days, weeks, or months. This paper is a general review of CFP including the human health effects of exposure to ciguatoxins (CTXs), diagnosis, human pathophysiology of CFP, treatment, detection of CTXs in fish, epidemiology of the illness, global dimensions, prevention, future directions, and recommendations for clinicians and patients. It updates and expands upon the previous review of CFP published by Friedman et al. (2008) and addresses new insights and relevant emerging global themes such as climate and environmental change, international market issues, and socioeconomic impacts of CFP. It also provides a proposed universal case definition for CFP designed to account for the variability in symptom presentation across different geographic regions. Information that is important but unchanged since the previous review has been reiterated. This article is intended for a broad audience, including resource and fishery managers, commercial and recreational fishers, public health officials, medical professionals, and other interested parties.
Effect of Heat Treatment on the Microstructure and Mechanical Properties of Nitrogen-Alloyed High-Mn Austenitic Hot Work Die Steel
Authors: Zhang Yi , Li Jing , Shi Cheng-Bin , Qi Yong-Feng , Zhu Qin-Tian
Published: March 2017

In view of the requirements for mechanical properties and service life above 650 °C, a high-Mn austenitic hot work die steel, instead of traditional martensitic hot work die steel such as H13, was developed in the present study. The effect of heat treatment on the microstructure and mechanical properties of the newly developed work die steel was studied. The results show that the microstructure of the high-Mn as-cast electroslag remelting (ESR) ingot is composed of γ-Fe, V(C,N), and Mo2C. V(C,N) is an irregular multilateral strip or slice shape with severe angles. Most eutectic Mo2C carbides are lamellar fish-skeleton-like, except for a few that are rod-shaped. With increasing solid solution time and temperature, the increased hardness caused by solid solution strengthening exceeds the effect of decreased hardness caused by grain size growth, but this trend is reversed later. As a result, the hardness of specimens after various solid solution heat treatments increases first and then decreases. The optimal combination of hardness and austenitic grain size can be obtained by soaking for 2 h at 1170 °C. The maximum Rockwell hardness (HRC) is 47.24 HRC, and the corresponding austenite average grain size is 58.4 μm. When the solid solution time is 3 h at 1230 °C, bimodality presented in the histogram of the austenite grain size as a result of further progress in secondary recrystallization. Compared with the single-stage aging, the maximum impact energy of the specimen after two-stage aging heat treatment was reached at 16.2 J and increased by 29.6%, while the hardness decreased by 1–2 HRC. After two-stage aging heat treatment, the hardness of steel reached the requirements of superior grade H13, and the maximum impact energy was 19.6% higher than that of superior grade H13, as specified in NADCA#207-2003.
Reducing the Entrainment of Gangue Fines in Low Grade Microcrystalline Graphite Ore Flotation Using Multi-Stage Grinding-Flotation Process
Authors: Weng Xiaoqing , Li Hongqiang , Song Shaoxian , Liu Yanyan
Published: March 2017

A suitable grinding fineness and flow-sheet could potentially reduce the mechanical entrainment of gangue minerals in the flotation process of microcrystalline graphite. In this study, the suitable grinding fineness of a commercial graphite ore was estimated by mineralogy analysis and laboratory grind-flotation tests. The target grind size of this ore should be 92% passing 74 μm based on the mineralogical evaluation and the flotation performance. A comparison of a single-stage and a three-stage grinding circuit was conducted. Experimental results demonstrated that the three-stage grinding circuit could effectively improve the separation effect, which was attributed to the reduction of slimes. In the end, a more desirable beneficiation result was obtained with the application of three-stage grinding-flotation process by minimizing gangue entrainment.
2-Hydroxymelatonin, a Predominant Hydroxylated Melatonin Metabolite in Plants, Shows Antitumor Activity against Human Colorectal Cancer Cells
Authors: Yang Yi , Zhou Rui , Park So-Yeon , Back Kyoungwhan , Bae Woo , Kim Kyung , Kim Hangun
Published: March 2017

2-Hydroxymelatonin is a predominant hydroxylated melatonin metabolite in plants. To investigate whether it has potent cytotoxic effects on colorectal cancer cells, four colorectal cancer cell lines, Caco2, HCT116, DLD1, and CT26, were treated with 2-hydroxymelatonin and melatonin. 2-Hydroxymelatonin had a much lower IC50 value than melatonin in the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The cytotoxic effect of 2-hydroxymelatonin was much stronger than that of melatonin at high concentrations (1000 or 2000 μM) in HCT116, DLD1, and CT26 cells, but only at intermediate concentrations (250 or 500 μM) in Caco2 cells. The cytotoxicity of 2-hydroxymelatonin was induced through activation of the apoptotic signaling pathway, as confirmed by Hoechst staining and Annexin V-FITC/propidium iodide double labeling of cells treated with a lethal dose (1 mM). However, sub-lethal doses of 2-hydroxymelatonin inhibited the invasive ability of Caco2 cells. Epithelial-mesenchymal transition (EMT) markers were significantly regulated by 2-hydroxymelatonin. Overall, the anti-cancer activity of 2-hydroxymelatonin is more potent than that of melatonin. Taken together, 2-hydroxymelatonin exhibits potent anti-cancer activity against human colorectal cancer cells via induction of apoptosis and inhibition of EMT.
Spirobifluorene Core-Based Novel Hole Transporting Materials for Red Phosphorescence OLEDs
Authors: Braveenth Ramanaskanda , Bae Hyeong , Nguyen Quynh , Ko Haye , Lee Choong , Kim Hyeong , Kwon Jang , Chai Kyu
Published: March 2017

Two new hole transporting materials, named HTM 1A and HTM 1B, were designed and synthesized in significant yields using the well-known Buchwald Hartwig and Suzuki cross- coupling reactions. Both materials showed higher decomposition temperatures (over 450 °C) at 5% weight reduction and HTM 1B exhibited a higher glass transition temperature of 180 °C. Red phosphorescence-based OLED devices were fabricated to analyze the device performances compared to Spiro-NPB and NPB as reference hole transporting materials. Devices consist of hole transporting material as HTM 1B showed better maximum current and power efficiencies of 16.16 cd/A and 11.17 lm/W, at the same time it revealed an improved external quantum efficiency of 13.64%. This efficiency is considerably higher than that of Spiro-NPB and NPB-based reference devices.
Laxative Effects of Total Diterpenoids Extracted from the Roots of Euphorbia pekinensis Are Attributable to Alterations of Aquaporins in the Colon
Authors: Wang Kuilong , Liu Lian , Huang Jianyu , Yu Hongli , Wu Hao , Duan Yu , Cui Xiaobing , Zhang Xingde , Liu Liping , Wang Wei
Published: March 2017

This study was designed to evaluate the toxic effects of total diterpenoids extracted from the roots of Euphorbia pekinensis (TDEP) on the mouse colon and to clarify the mechanism. Dried powdered roots of E. pekinensis were extracted with chloroform, and then the extract (6.7 g) was subjected to column chromatography and preparative TLC, giving TDEP. Using the HPLC-DAD method, the purity of TDEP was determined as 85.26%. Mice were orally administered with TDEP (3.942, 19.71 and 39.42 mg/kg), after which fecal water content and colon water content were examined. Both of them increased over time after TDEP administration, accompanied by severe diarrhea. Three hours after TDEP administration, the animals were sacrificed to obtain their colons. The mRNA and protein expression levels of aquaporin 1 (AQP1), AQP3 and AQP4 in the colon were measured using real-time RT-PCR and Western blotting, respectively. TDEP significantly increased the levels of AQP3 and AQP4, but decreased that of AQP1 in dose-dependent manners. Similarly, Pekinenin C, a casbane diterpenoid, significantly increased AQP3 protein and mRNA expressions in human intestinal epithelial cells (HT-29). Histopathological examination revealed that the colon was not significantly damaged. The laxative effects of E. pekinensis were associated with the alterations of AQPs in the colon by TDEP.
Food Insecurity, Poor Diet Quality, and Suboptimal Intakes of Folate and Iron Are Independently Associated with Perceived Mental Health in Canadian Adults
Authors: Davison Karen , Gondara Lovedeep , Kaplan Bonnie
Published: March 2017

Background: To address nutrition-related population mental health data gaps, we examined relationships among food insecurity, diet quality, and perceived mental health. Methods: Stratified and logistic regression analyses of respondents aged 19–70 years from the Canadian Community Health Survey, Cycle 2.2 were conducted (n = 15,546). Measures included the Household Food Security Survey Module, diet quality (i.e., comparisons to the Dietary Reference Intakes, Healthy Eating Index), perceived mental health (poor versus good), sociodemographics, and smoking. Results: In this sample, 6.9% were food insecure and 4.5% reported poor mental health. Stratified analysis of food security and mental health status by age/gender found associations for poor diet quality, protein, fat, fibre, and several micronutrients (p-values < 0.05); those who were food insecure tended to have higher suboptimal intakes (p-values < 0.05). After adjustment for covariates, associations in relation to mental health emerged for food insecurity (OR = 1.60, 95% CI 1.45–1.71), poor diet quality (1.61, 95% CI 1.34–1.81), and suboptimal intakes of folate (OR = 1.58, 95% CI 1.17–1.90) and iron (OR = 1.45, 95% CI 1.23–1.88). Conclusions: Population approaches that improve food security and intakes of high quality diets may protect people from poor mental health.
Preparation and Application of Starch/Polyvinyl Alcohol/Citric Acid Ternary Blend Antimicrobial Functional Food Packaging Films
Authors: Wu Zhijun , Wu Jingjing , Peng Tingting , Li Yutong , Lin Derong , Xing Baoshan , Li Chunxiao , Yang Yuqiu , Yang Li , Zhang Lihua , Ma Rongchao , Wu Weixiong , Lv Xiaorong , Dai Jianwu , Han Guoquan
Published: March 2017

Ternary blend films were prepared with different ratios of starch/polyvinyl alcohol (PVA)/citric acid. The films were characterized by field emission scanning electron microscopy (FE-SEM), thermogravimetric analysis, as well as Fourier transform infrared (FTIR) analysis. The influence of different ratios of starch/polyvinyl alcohol (PVA)/citric acid and different drying times on the performance properties, transparency, tensile strength (TS), water vapor permeability (WVP), water solubility (WS), color difference (ΔE), and antimicrobial activity of the ternary blends films were investigated. The starch/polyvinyl alcohol/citric acid (S/P/C1:1:0, S/P/C3:1:0.08, and S/P/C3:3:0.08) films were all highly transparent. The S/P/C3:3:0.08 had a 54.31 times water-holding capacity of its own weight and its mechanical tensile strength was 46.45 MPa. In addition, its surface had good uniformity and compactness. The S/P/C3:1:0.08 and S/P/C3:3:0.08 showed strong antimicrobial activity to Listeria monocytogenes and Escherichia coli, which were the food-borne pathogenic bacteria used. The freshness test results of fresh figs showed that all of the blends prevented the formation of condensed water on the surface of the film, and the S/P/C3:1:0.08 and S/P/C3:3:0.08 prevented the deterioration of figs during storage. The films can be used as an active food packaging system due to their strong antibacterial effect.
Selecting Appropriate Spatial Scale for Mapping Plastic-Mulched Farmland with Satellite Remote Sensing Imagery
Authors: Hasituya  , Chen Zhongxin , Wang Limin , Liu Jia
Published: March 2017

In recent years, the area of plastic-mulched farmland (PMF) has undergone rapid growth and raised remarkable environmental problems. Therefore, mapping the PMF plays a crucial role in agricultural production, environmental protection and resource management. However, appropriate data selection criteria are currently lacking. Thus, this study was carried out in two main plastic-mulching practice regions, Jizhou and Guyuan, to look for an appropriate spatial scale for mapping PMF with remote sensing. The average local variance (ALV) function was used to obtain the appropriate spatial scale for mapping PMF based on the GaoFen-1 (GF-1) satellite imagery. Afterwards, in order to validate the effectiveness of the selected method and to interpret the relationship between the appropriate spatial scale derived from the ALV and the spatial scale with the highest classification accuracy, we classified the imagery with varying spatial resolution by the Support Vector Machine (SVM) algorithm using the spectral features, textural features and the combined spectral and textural features respectively. The results indicated that the appropriate spatial scales from the ALV lie between 8 m and 20 m for mapping the PMF both in Jizhou and Guyuan. However, there is a proportional relation: the spatial scale with the highest classification accuracy is at the 1/2 location of the appropriate spatial scale generated from the ALV in Jizhou and at the 2/3 location of the appropriate spatial scale generated from the ALV in Guyuan. Therefore, the ALV method for quantitatively selecting the appropriate spatial scale for mapping PMF with remote sensing imagery has theoretical and practical significance.
Building a Relationship between Robot Characteristics and Teleoperation User Interfaces
Authors: Mortimer Michael , Horan Ben , Seyedmahmoudian Mehdi
Published: March 2017

The Robot Operating System (ROS) provides roboticists with a standardized and distributed framework for real-time communication between robotic systems using a microkernel environment. This paper looks at how ROS metadata, Unified Robot Description Format (URDF), Semantic Robot Description Format (SRDF), and its message description language, can be used to identify key robot characteristics to inform User Interface (UI) design for the teleoperation of heterogeneous robot teams. Logical relationships between UI components and robot characteristics are defined by a set of relationship rules created using relevant and available information including developer expertise and ROS metadata. This provides a significant opportunity to move towards a rule-driven approach for generating the designs of teleoperation UIs; in particular the reduction of the number of different UI configurations required to teleoperate each individual robot within a heterogeneous robot team. This approach is based on using an underlying rule set identifying robots that can be teleoperated using the same UI configuration due to having the same or similar robot characteristics. Aside from reducing the number of different UI configurations an operator needs to be familiar with, this approach also supports consistency in UI configurations when a teleoperator is periodically switching between different robots. To achieve this aim, a Matlab toolbox is developed providing users with the ability to define rules specifying the relationship between robot characteristics and UI components. Once rules are defined, selections that best describe the characteristics of the robot type within a particular heterogeneous robot team can be made. A main advantage of this approach is that rather than specifying discrete robots comprising the team, the user can specify characteristics of the team more generally allowing the system to deal with slight variations that may occur in the future. In fact, by using the defined relationship rules and characteristic selections, the toolbox can automatically identify a reduced set of UI configurations required to control possible robot team configurations, as opposed to the traditional ad-hoc approach to teleoperation UI design. In the results section, three test cases are presented to demonstrate how the selection of different robot characteristics builds a number of robot characteristic combinations, and how the relationship rules are used to determine a reduced set of required UI configurations needed to control each individual robot in the robot team.
DNA Sequencing Sensors: An Overview
Authors: Garrido-Cardenas Jose , Garcia-Maroto Federico , Alvarez-Bermejo Jose , Manzano-Agugliaro Francisco
Published: March 2017

The first sequencing of a complete genome was published forty years ago by the double Nobel Prize in Chemistry winner Frederick Sanger. That corresponded to the small sized genome of a bacteriophage, but since then there have been many complex organisms whose DNA have been sequenced. This was possible thanks to continuous advances in the fields of biochemistry and molecular genetics, but also in other areas such as nanotechnology and computing. Nowadays, sequencing sensors based on genetic material have little to do with those used by Sanger. The emergence of mass sequencing sensors, or new generation sequencing (NGS) meant a quantitative leap both in the volume of genetic material that was able to be sequenced in each trial, as well as in the time per run and its cost. One can envisage that incoming technologies, already known as fourth generation sequencing, will continue to cheapen the trials by increasing DNA reading lengths in each run. All of this would be impossible without sensors and detection systems becoming smaller and more precise. This article provides a comprehensive overview on sensors for DNA sequencing developed within the last 40 years.
Deciphering Egyptian Hieroglyphs: Towards a New Strategy for Navigation in Museums
Authors: Duque-Domingo Jaime , Herrera Pedro , Valero Enrique , Cerrada Carlos
Published: March 2017

This work presents a novel strategy to decipher fragments of Egyptian cartouches identifying the hieroglyphs of which they are composed. A cartouche is a drawing, usually inside an oval, that encloses a group of hieroglyphs representing the name of a monarch. Aiming to identify these drawings, the proposed method is based on several techniques frequently used in computer vision and consists of three main stages: first, a picture of the cartouche is taken as input and its contour is localized. In the second stage, each hieroglyph is individually extracted and identified. Finally, the cartouche is interpreted: the sequence of the hieroglyphs is established according to a previously generated benchmark. This sequence corresponds to the name of the king. Although this method was initially conceived to deal with both high and low relief writing in stone, it can be also applied to painted hieroglyphs. This approach is not affected by variable lighting conditions, or the intensity and the completeness of the objects. This proposal has been tested on images obtained from the Abydos King List and other Egyptian monuments and archaeological excavations. The promising results give new possibilities to recognize hieroglyphs, opening a new way to decipher longer texts and inscriptions, being particularly useful in museums and Egyptian environments. Additionally, devices used for acquiring visual information from cartouches (i.e., smartphones), can be part of a navigation system for museums where users are located in indoor environments by means of the combination of WiFi Positioning Systems (WPS) and depth cameras, as unveiled at the end of the document.