bluuebunny/crossref_metadata_2025 huggingface dataset:
Toward Network Worm Victims Identification Based on Cascading Motif Discovery
Authors: Hu Hangyu , Wang Mingda , Ouyang Mingyu , Hu Guangmin
Published: February 2019

Network worms spread widely over the global network within a short time, which are increasingly becoming one of the most potential threats to network security. However, the performance of traditional packet-oriented signature-based methods is questionable in the face of unknown worms, while anomaly-based approaches often exhibit high false positive rates. It is a common scenario that the life cycle of network worms consists of the same four stages, in which the target discovery phase and the transferring phase have specific interactive patterns. To this end, we propose Network Flow Connectivity Graph (NFCG) for identifying network worm victims. We model the flow-level interactions as graph and then identify sets of frequently occurring motifs related to network worms through Cascading Motif Discovery algorithm. In particular, a cascading motif is jointly extracted from graph target discovery phase and transferring phase. If a cascading motif exists in a connected behavior graph of one host, the host would be identified as a suspicious worm victim; the excess amount of suspicious network worm victims is used to reveal the outbreak of network worms. The simulated experiments show that our proposed method is effective and efficient in network worm victims’ identification and helpful for improving network security.
Bio-Inspired Autonomous Visual Vertical and Horizontal Control of a Quadrotor Unmanned Aerial Vehicle
Authors: Armendariz Saul , Becerra Victor , Bausch Nils
Published: February 2019

Near-ground manoeuvres, such as landing, are key elements in unmanned aerial vehicle navigation. Traditionally, these manoeuvres have been done using external reference frames to measure or estimate the velocity and the height of the vehicle. Complex near-ground manoeuvres are performed by flying animals with ease. These animals perform these complex manoeuvres by exclusively using the information from their vision and vestibular system. In this paper, we use the Tau theory, a visual strategy that, is believed, is used by many animals to approach objects, as a solution for relative ground distance control for unmanned vehicles. In this paper, it is shown how this approach can be used to perform near-ground manoeuvres in a vertical and horizontal manner on a moving target without the knowledge of height and velocity of either the vehicle or the target. The proposed system is tested with simulations. Here, it is shown that, using the proposed methods, the vehicle is able to perform landing on a moving target, and also they enable the user to choose the dynamic characteristics of the approach.
Multilayer Perceptron Neural Network-Based QoS-Aware, Content-Aware and Device-Aware QoE Prediction Model: A Proposed Prediction Model for Medical Ultrasound Streaming Over Small Cell Networks
Authors: Rehman Ikram U. , Nasralla Moustafa M. , Philip Nada Y.
Published: February 2019

This paper presents a QoS-aware, content-aware and device-aware nonintrusive medical QoE (m-QoE) prediction model over small cell networks. The proposed prediction model utilises a Multilayer Perceptron (MLP) neural network to predict m-QoE. It also acts as a platform to maintain and optimise the acceptable diagnostic quality through a device-aware adaptive video streaming mechanism. The proposed model is trained for an unseen dataset of input variables such as QoS, content features and display device characteristics, to produce an output value in the form of m-QoE (i.e. MOS). The efficiency of the proposed model is validated through subjective tests carried by medical experts. The prediction accuracy obtained via the correlation coefficient and Root Mean-Square-Error (RMSE) indicates that the proposed model succeeds in measuring m-QoE closer to the visual perception of the medical experts. Furthermore, we have addressed two main research questions: (1) How significant is ultrasound video content type in determining m-QoE? (2) How much of a role does the screen size and device resolution play in medical experts’ diagnostic experience? The former is answered through the content classification of ultrasound video sequences based on their spatiotemporal features, by including these features in the proposed prediction model, and validating their significance through medical experts’ subjective ratings. The latter is answered by conducting a novel subjective experiment of the ultrasound video sequences across multiple devices.
Efficiency of Different Machine Layouts for Chain Flail Delimbing, Debarking and Chipping
Authors: McEwan Andrew , Brink Michal , Spinelli Raffaele
Published: February 2019

Based on data collected from seven commercial harvesting operations in Western Australia, the study developed a productivity model for chain flail delimber–debarker–chippers (CFDDCs) used in blue gum (Eucalyptus globulus Labill.) plantations. The tests covered 45 h and 3395 cycles, and were conducted using time-study techniques. Despite the observational character of the study and the dampening effect of multi-tree processing, the study yielded a viable prediction model for estimating CFDDC productivity as a function of mean tree size, tree form, bark–wood bond strength (BWBS), and machine type. Productivity increased with mean tree size on a logarithmic scale, and was lower for poorly formed trees and high BWBS. Under equal conditions, a separate delimber–debarker and a chipper were 10% to 20% less productive than the integrated delimber–debarker–chipper. Productivity estimates were consistent with those reported in published case studies of CFDDCs used in planted Eucalyptus. Neither this study nor any of the previous ones could offer a reliable estimate of long-term machine utilization, which would be an ideal subject for future research.
Impact of Biogenic Amines on Food Quality and Safety
Authors: Ruiz-Capillas Claudia , Herrero Ana
Published: February 2019

Today, food safety and quality are some of the main concerns of consumer and health agencies around the world. Our current lifestyle and market globalization have led to an increase in the number of people affected by food poisoning. Foodborne illness and food poisoning have different origins (bacteria, virus, parasites, mold, contaminants, etc.), and some cases of food poisoning can be traced back to chemical and natural toxins. One of the toxins targeted by the Food and Drug Administration (FDA) and European Food Safety Authority (EFSA) is the biogenic amine histamine. Biogenic amines (BAs) in food constitute a potential public health concern due to their physiological and toxicological effects. The consumption of foods containing high concentrations of biogenic amines has been associated with health hazards. In recent years there has been an increase in the number of food poisoning cases associated with BAs in food, mainly in relation to histamines in fish. We need to gain a better understanding of the origin of foodborne disease and how to control it if we expect to keep people from getting ill. Biogenic amines are found in varying concentrations in a wide range of foods (fish, cheese, meat, wine, beer, vegetables, etc.), and BA formation is influenced by different factors associated with the raw material making up food products, microorganisms, processing, and conservation conditions. Moreover, BAs are thermostable. Biogenic amines also play an important role as indicators of food quality and/or acceptability. Hence, BAs need to be controlled in order to ensure high levels of food quality and safety. All of these aspects will be addressed in this review.
Nucleolar Expression and Chromosomal Associations in Robertsonian Spermatocytes of Mus musculus domesticus
Authors: López-Moncada Fernanda , Tapia Daniel , Zuñiga Nolberto , Ayarza Eliana , López-Fenner Julio , Redi Carlo Alberto , Berríos Soledad
Published: February 2019

We studied and compared the nucleolar expression or nucleoli from specific bivalents in spermatocytes of the standard Mus musculus domesticus 2n = 40, of Robertsonian (Rb) homozygotes 2n = 24 and heterozygotes 2n = 32. We analyzed 200 nuclear microspreads of each specific nucleolar chromosome and spermatocyte karyotype, using FISH to identify specific nucleolar bivalents, immunofluorescence for both fibrillarin of the nucleolus and the synaptonemal complex of the bivalents, and DAPI for heterochromatin. There was nucleolar expression in all the chromosomal conditions studied. By specific nucleolar bivalent, the quantitative relative nucleolar expression was higher in the bivalent 12 than in its derivatives, lower in the bivalent 15 than in its derivatives and higher in the bivalent 16 than its Rb derivatives. In the interactions between non-homologous chromosomal domains, the nucleolar bivalents were preferentially associated through pericentromeric heterochromatin with other bivalents of similar morphology and sometimes with other nucleolar bivalents. We suggest that the nucleolar expression in Rb nucleolar chromosomes is modified as a consequence of different localization of ribosomal genes (NOR) in the Rb chromosomes, its proximity to heterochromatin and its associations with chromosomes of the same morphology.
Enemy and Officers in Emilio Lussu’s Un anno sull’Altipiano
Authors: Marcucci Dario
Published: February 2019

This essay explores the concept of enemy in Emilio Lussu’s WWI memoir Un anno sull’Altipiano (A Soldier on the Southern Front, 1938). The memoir portrays the conflict on the oft-forgotten Alpine Front, where Italian and Austro-Hungarian armies clashed from 1915 to 1918 in a series of battles fought at high altitudes. I argue that two crucial dynamics of modern warfare shape the concept of enemy in WWI literature: the impossibility of close-range encounters, which was due to the superiority of defensive firepower, and hatred for one’s own officers, which stemmed from the corrosive environment of the trenches, where the aggressive attitude of high-ranking officers often led hundreds of thousands to pointless death. I show how, in Lussu’s memoir, these dynamics subvert the traditional image of the enemy as imposed by military propaganda, and finally elicit feelings of empathy.
Functionalized Periodic Mesoporous Organosilica Nanoparticles for Loading and Delivery of Suramin
Authors: Knežević Nikola Ž. , Djordjević Sanja , Kojić Vesna , Janaćković Djordje
Published: February 2019

Suramin (SUR) is a known drug for treating parasitic infections though research studies and some clinical trials have shown its applicability for a plethora of other diseases. Herein we report on a novel SUR nanocarrier for the drug delivery to cells. We synthesized periodic mesoporous organosilica nanoparticles with spherical morphology, having mean diameter of 240 nm and high surface area (778 m2/g). The material’s surface is modified with an amine-containing organic moiety N-[3-(Trimethoxysilyl)propyl]ethylenediamine (DA), followed by surface attachment with the drug. The rate of SUR release in physiological condition was low, though in vitro experiments on MRC-5 cell line demonstrate effective delivery of the drug to the cells and low toxicity of the materials without the adsorbed drug. These results are promising for opening new treatment strategies with SUR-bearing nanocarriers, with high efficiency and low adverse effects on healthy tissues.
Syntheses, Structures, and Catalytic Hydrocarbon Oxidation Properties of N-Heterocycle-Sulfonated Schiff Base Copper(II) Complexes
Authors: Hazra Susanta , Rocha Bruno G. M. , Guedes da Silva M. Fátima C. , Karmakar Anirban , Pombeiro Armando J. L.
Published: February 2019

Reaction of the o-[(o-hydroxyphenyl)methylideneamino]benzenesulfonic acid (H2L) (1) with CuCl2·2H2O in the presence of pyridine (py) leads to [Cu(L)(py)(EtOH)] (2) which, upon further reaction with 2,2’-bipyridine (bipy), pyrazine (pyr), or piperazine (pip), forms [Cu(L)(bipy)]·MeOH (3), [Cu2(L)2(μ-pyr)(MeOH)2] (4), or [Cu2(L)2(μ-pip)(MeOH)2] (5), respectively. The Schiff base (1) and the metal complexes (2–5) are stabilized by a number of non-covalent interactions to form interesting H-bonded multidimensional polymeric networks (except 3), such as zigzag 1D chain (in 1), linear 1D chain (in 2), hacksaw double chain 1D (in 4) and 2D motifs (in 5). These copper(II) complexes (2–5) catalyze the peroxidative oxidation of cyclic hydrocarbons (cyclooctane, cyclohexane, and cyclohexene) to the corresponding products (alcohol and ketone from alkane; alcohols, ketone, and epoxide from alkene), under mild conditions. For the oxidation of cyclooctane with hydrogen peroxide as oxidant, used as a model reaction, the best yields were generally achieved for complex 3 in the absence of any promoter (20%) or in the presence of py or HNO3 (26% or 30%, respectively), whereas 2 displayed the highest catalytic activity in the presence of HNO3 (35%). While the catalytic reactions were significantly faster with py, the best product yields were achieved with the acidic additive.
Surface Modification of Electrospun Scaffolds for Endothelialization of Tissue-Engineered Vascular Grafts Using Human Cord Blood-Derived Endothelial Cells
Authors: Ardila Diana , Liou Jr-Jiun , Maestas David , Slepian Marvin , Badowski Michael , Wagner William , Harris David , Vande Geest Jonathan
Published: February 2019

Tissue engineering has gained attention as an alternative approach for developing small diameter tissue-engineered vascular grafts intended for bypass surgery, as an option to treat coronary heart disease. To promote the formation of a healthy endothelial cell monolayer in the lumen of the graft, polycaprolactone/gelatin/fibrinogen scaffolds were developed, and the surface was modified using thermoforming and coating with collagen IV and fibronectin. Human cord blood-derived endothelial cells (hCB-ECs) were seeded onto the scaffolds and the important characteristics of a healthy endothelial cell layer were evaluated under static conditions using human umbilical vein endothelial cells as a control. We found that polycaprolactone/gelatin/fibrinogen scaffolds that were thermoformed and coated are the most suitable for endothelial cell growth. hCB-ECs can proliferate, produce endothelial nitric oxide synthase, respond to interleukin 1 beta, and reduce platelet deposition.
Moscatilin Inhibits Growth of Human Esophageal Cancer Xenograft and Sensitizes Cancer Cells to Radiotherapy
Authors: Chen Wun-Ke , Chen Chien-An , Chi Chih-Wen , Li Li-Hui , Lin Chin-Ping , Shieh Hui-Ru , Hsu Ming-Ling , Ko Chun-Chuan , Hwang Jeng-Jong , Chen Yu-Jen
Published: February 2019

Esophageal cancer prognosis remains poor in current clinical practice. We previously reported that moscatilin can induce apoptosis and mitotic catastrophe in esophageal cancer cells, accompanied by upregulation of polo-like kinase 1 (Plk1) expression. We aimed to validate in vitro activity and Plk1 expression in vivo following moscatilin treatment and to examine the treatment’s radiosensitizing effect. Human esophageal cancer cells were implanted in nude mice. Moscatilin was intraperitoneally (i.p.) injected into the mice. Tumor size, body weight, white blood cell counts, and liver and renal function were measured. Aberrant mitosis and Plk1 expression were assessed. Colony formation was used to measure survival fraction after radiation. Moscatilin significantly suppressed tumor growth in mice bearing human esophageal xenografts without affecting body weight, white blood cell counts, or liver and renal function. Moscatilin also induced aberrant mitosis and apoptosis. Plk1 expression was markedly upregulated in vivo. Moreover, moscatilin pretreatment enhanced CE81T/VGH and BE3 cell radioresponse in vitro. Moscatilin may inhibit growth of human esophageal tumors and sensitize esophageal cancer cells to radiation therapy.
PET Radiopharmaceuticals for Specific Bacteria Imaging: A Systematic Review
Authors: Auletta Sveva , Varani Michela , Horvat Rika , Galli Filippo , Signore Alberto , Hess Søren
Published: February 2019

Background: Bacterial infections are still one of the main factors associated with mortality worldwide. Many radiopharmaceuticals were developed for bacterial imaging, both with single photon emission computed tomography (SPECT) and positron emission tomography (PET) isotopes. This review focuses on PET radiopharmaceuticals, performing a systematic literature review of published studies between 2005 and 2018. Methods: A systematic review of published studies between 2005 and 2018 was performed. A team of reviewers independently screened for eligible studies. Because of differences between studies, we pooled the data where possible, otherwise, we described separately. Quality of evidence was assessed by Quality Assessment of Diagnostic Accuracy Studies (QUADAS) approach. Results: Eligible papers included 35 published studies. Because of the heterogeneity of animal models and bacterial strains, we classified studies in relation to the type of bacterium: Gram-positive, Gram-negative, Gram-positive and negative, others. Conclusions: Results highlighted the availability of many promising PET radiopharmaceuticals for bacterial imaging, despite some bias related to animal selection and index test, but few have been translated to human subjects. Results showed a lack of standardized infection models and experimental settings.
Rifabutin-Based Rescue Therapy for Helicobacter pylori Eradication: A Long-Term Prospective Study in a Large Cohort of Difficult-to-Treat Patients
Authors: Ribaldone Davide Giuseppe , Fagoonee Sharmila , Astegiano Marco , Durazzo Marilena , Morgando Anna , Sprujevnik Tatiana , Giordanino Chiara , Baronio Monica , De Angelis Claudio , Saracco Giorgio Maria , Pellicano Rinaldo
Published: February 2019

The most commonly used regimens fail to eradicate Helicobacter pylori (H. pylori) infection in 5–10% of patients. Those not cured with treatments based on amoxicillin, clarithromycin, nitroimidazoles, fluoroquinolones, bismuth or tetracycline have no other conventional options thereafter. In this prospective long-term monocentric study, patients who failed to eradicate H. pylori following treatment with all conventional antibiotics were included. All subjects were treated with rifabutin 150 mg, amoxicillin 1 g and a standard dose of proton pump inhibitor, twice daily for 14 days. A negative 13C-urea breath test was used four weeks after treatment completion as an index of H. pylori eradication. Three hundred and two patients were included. Fifty-four percent (164/302) had peptic ulcer disease while 45.7% (138/302) had gastritis or functional dyspepsia. Per-protocol eradication and intention-to-treat eradication were achieved in 72.7% and 71.5%, respectively. A univariate analysis showed that gender, ethnic background, smoking habits and familial history of gastric diseases were not predictive factors of response, while with multiple logistic regression analysis, the ethnic background (Italian) predicted a poor response in the second period of the study (2010–2017). In conclusion, this study on a large cohort of very difficult-to-treat patients showed that rifabutin-based rescue therapy is an acceptable and safe strategy after multiple eradication failures with conventional antibiotics.
Obesity, Inflammation, and Prostate Cancer
Authors: Fujita Kazutoshi , Hayashi Takuji , Matsushita Makoto , Uemura Motohide , Nonomura Norio
Published: February 2019

The prevalence of obesity is increasing in the world, and obesity-induced disease, insulin-resistance, cardiovascular disease, and malignancies are becoming a problem. Epidemiological studies have shown that obesity is associated with advanced prostate cancer and that obese men with prostate cancer have a poorer prognosis. Obesity induces systemic inflammation via several mechanisms. High-fat diet-induced prostate cancer progresses via adipose-secretory cytokines or chemokines. Inflammatory cells play important roles in tumor progression. A high-fat diet or obesity changes the local profile of immune cells, such as myeloid-derived suppressor cells and macrophages, in prostate cancer. Tumor-associated neutrophils, B cells, and complements may promote prostate cancer in the background of obesity. Interventions to control systemic and/or local inflammation and changes in lifestyle may also be viable therapies for prostate cancer.
The Interaction between Genetic Polymorphisms in FTO and TCF7L2 Genes and Dietary Intake with Regard to Body Mass and Composition: An Exploratory Study
Authors: Nasreddine Lara , Akika Reem , Mailhac Aurelie , Tamim Hani , Zgheib Nathalie
Published: February 2019

In contrast to the large number of genetic studies on obesity, there has been significantly less nutrigenetics investigation of the interaction between diet and single nucleotide polymorphisms (SNPs) in obesity, especially within Eastern Mediterranean populations. The aim of this study was to evaluate the potential interactions between three candidate SNPs, namely, rs1558902 and rs9939609 in the fat mass and obesity (FTO) gene and the rs7903146 variant of the Transcription factor 7 like 2 (TCF7L2) gene, and macronutrient intake with regard to obesity, body fat, and muscle composition. Three hundred and eight healthy Lebanese adults were included in this study. Data collection included a questionnaire for demographics and lifestyle in addition to a detailed dietary assessment using a culture-specific 80-item semi-quantitative food frequency questionnaire. This was coupled with anthropometric measurements and peripheral blood withdrawal for DNA and genotyping using Taqman allele discrimination assays. The two FTO candidate SNPs were not associated with risk of obesity in this population sample, yet there was a trend, though not a significant one, towards lower muscle mass among carriers of the risk allele of either FTO SNPs. To our knowledge, these results have not been previously reported. As for the TCF7L2 rs7903146 variant, results were congruent with the literature, given that individuals who were homozygous for the risk allele had significantly higher body mass index (BMI) and body fat despite lower intakes of saturated fat. Similar interactions, though not significant, were shown with muscle mass, whereby individuals who were homozygous for the risk allele had lower muscle mass with higher intakes of saturated fat, a result that, to our knowledge, has not been previously reported.
Geometric No-Arbitrage Analysis in the Dynamic Financial Market with Transaction Costs
Authors: Tang Wanxiao , Zhao Jun , Zhao Peibiao
Published: February 2019

The present paper considers a class of financial market with transaction costs and constructs a geometric no-arbitrage analysis frame. Then, this paper arrives at the fact that this financial market is of no-arbitrage if and only if the curvature 2-form of a specific connection is zero. Furthermore, this paper derives the fact that the no-arbitrage condition for the one-period financial market is equivalent to the geometric no-arbitrage condition. Finally, an example states the equivalence between the geometric no-arbitrage condition and the existence of the solutions for a maximization problem of expected utility.
Analysis of High Temporal Resolution Land Use/Land Cover Trajectories
Authors: Mas Jean-François , Nogueira de Vasconcelos Rodrigo , Franca-Rocha Washington
Published: February 2019

In this study, methods, originally developed to assess life course trajectories, are explored in order to evaluate land change through the analysis of sequences of land use/cover. Annual land cover maps which describe land use/land cover change for the 1985–2017 period for a large region in Northeast Brazil were analyzed. The most frequent sequences, the entropy and the turbulence of the land trajectories, and the average time of permanence were computed. Clusters of similar sequences were determined using different dissimilarity measures. The effect of some covariates such as slope and distance from roads on land trajectories was also evaluated. The obtained results show the potential of these techniques to analyze land cover sequences since the availability of multidate land cover data with both, high temporal and thematic resolutions, is continuously increasing and poses significant challenges to data analysis.
Fabrication and Microstructure of Laminated HAP–45S5 Bioglass Ceramics by Spark Plasma Sintering
Authors: Meng Ye , Qiang Wenjiang , Pang Jingqin
Published: February 2019

Hydroxyapatite (HAP) has excellent biocompatibility with living bone tissue and does not cause defensive body reactions, therefore, it has become one of the most widely used calcium phosphate materials in dental and medical fields. However, its poor mechanical properties have been a substantial challenge in the application of HAP for the replacement of load-bearing or large bone defects. Laminated HAP–45S5 bioglass ceramics composites were prepared by the spark plasma sintering (SPS) technique. The interface structures between the HAP and 45S5 bioglass layers and the mechanical properties of the laminated composites were investigated. It was demonstrated that there was mutual transfer and exchange of Ca and Na atoms at the interface between 45S5 bioglass/HAP laminated layers, which contributed considerably to the interfacial bonding. Due from the laminated structure and strong interface bonding, laminated HAP–45S5 bioglass is recommended for structural applications.
Mechanical Properties of Gas Main Steels after Long-Term Operation and Peculiarities of Their Fracture Surface Morphology
Authors: Hutsaylyuk Volodymyr , Maruschak Pavlo , Konovalenko Ihor , Panin Sergey , Bishchak Roman , Chausov Mykola
Published: February 2019

Regularities of steel structure degradation of the “Novopskov-Aksay-Mozdok” gas main pipelines (Nevinnomysskaya CS) as well as the “Gorky-Center” pipelines (Gavrilovskaya CS) were studied. The revealed peculiarities of their degradation after long-term operation are suggested to be treated as a particular case of the damage accumulation classification (scheme) proposed by prof. H.M. Nykyforchyn. It is shown that the fracture surface consists of sections of ductile separation and localized zones of micro-spalling. The presence of the latter testifies to the hydrogen-induced embrittlement effect. However, the steels under investigation possess sufficiently high levels of the mechanical properties required for their further safe exploitation, both in terms of durability and cracking resistance.
Thermoelectric Properties of Ca3Co2−xMnxO6 (x = 0.05, 0.2, 0.5, 0.75, and 1)
Authors: Kanas Nikola , Singh Sathya Prakash , Rotan Magnus , Desissa Temesgen Debelo , Grande Tor , Wiik Kjell , Norby Truls , Einarsrud Mari-Ann
Published: February 2019

High-temperature instability of the Ca3Co4−yO9+δ and CaMnO3−δ direct p-n junction causing the formation of Ca3Co2−xMnxO6 has motivated the investigation of the thermoelectric performance of this intermediate phase. Here, the thermoelectric properties comprising Seebeck coefficient, electrical conductivity, and thermal conductivity of Ca3Co2−xMnxO6 with x = 0.05, 0.2, 0.5, 0.75, and 1 are reported. Powders of the materials were synthesized by the solid-state method, followed by conventional sintering. The material Ca3CoMnO6 (x = 1) demonstrated a large positive Seebeck coefficient of 668 μV/K at 900 °C, but very low electrical conductivity. Materials with compositions with x < 1 had lower Seebeck coefficients and higher electrical conductivity, consistent with small polaron hopping with an activation energy for mobility of 44 ± 6 kJ/mol and where both the concentration and mobility of hole charge carriers were proportional to 1−x. The conductivity reached about 11 S·cm−1 at 900 °C for x = 0.05. The material Ca3Co1.8Mn0.2O6 (x = 0.2) yielded a maximum zT of 0.021 at 900 °C. While this value in itself is not high, the thermodynamic stability and self-assembly of Ca3Co2−xMnxO6 layers between Ca3Co4−yO9+δ and CaMnO3−δ open for new geometries and designs of oxide-based thermoelectric generators.
Bio-Inspired 3D Infill Patterns for Additive Manufacturing and Structural Applications
Authors: Podroužek Jan , Marcon Marco , Ninčević Krešimir , Wan-Wendner Roman
Published: February 2019

The aim of this paper is to introduce and characterize, both experimentally and numerically, three classes of non-traditional 3D infill patterns at three scales as an alternative to classical 2D infill patterns in the context of additive manufacturing and structural applications. The investigated 3D infill patterns are biologically inspired and include Gyroid, Schwarz D and Schwarz P. Their selection was based on their beneficial mechanical properties, such as double curvature. They are not only known from nature but also emerge from numerical topology optimization. A classical 2D hexagonal pattern has been used as a reference. The mechanical performance of 14 cylindrical specimens in compression is quantitatively related to stiffness, peak load and weight. Digital image correlation provides accurate full-field deformation measurements and insights into periodic features of the surface strain field. The associated variability, which is inherent to the production and testing process, has been evaluated for 3 identical Gyroid specimens. The nonlinear material model for the preliminary FEM analysis is based on tensile test specimens with 3 different slicing strategies. The 3D infill patterns are generally useful when the extrusion orientation cannot be aligned with the build orientation and the principal stress field, i.e., in case of generative design, such as the presented branching structure, or any complex shape and boundary condition.
Research and Method of Roughness Prediction of a Curvilinear Surface after Titanium Alloy Turning
Authors: Matras Andrzej , Zębala Wojciech , Machno Magdalena
Published: February 2019

This paper deals with the optimization of process parameters (such as cutting speed and feed rate) to minimize surface roughness in the turning of a titanium alloy (Ti-6Al-4V) workpiece with spherical shape. In the first part of the article, based on the results analysis, a mathematical model is developed. It is shown that cutting speed has little effect on the surface roughness. The second part of the paper presents the application of the developed method to optimize cutting data such as feed rate in order to obtain the surface roughness parameters Ra and Rz of the curvilinear surface of the titanium alloy workpiece at acceptable and aligned, values regardless of the surface shape and its tilted angle. A case study verifies the correctness of the proposed method. The machining time was substantially shortened in comparison to the non-optimized cutting process.
Model Selection Criteria on Beta Regression for Machine Learning
Authors: Espinheira Patrícia L. , da Silva Luana C. Meireles , Silva Alisson de Oliveira , Ospina Raydonal
Published: February 2019

Beta regression models are a class of supervised learning tools for regression problems with univariate and limited response. Current fitting procedures for beta regression require variable selection based on (potentially problematic) information criteria. We propose model selection criteria that take into account the leverage, residuals, and influence of the observations, both to systematic linear and nonlinear components. To that end, we propose a Predictive Residual Sum of Squares (PRESS)-like machine learning tool and a prediction coefficient, namely P 2 statistic, as a computational procedure. Monte Carlo simulation results on the finite sample behavior of prediction-based model selection criteria P 2 are provided. We also evaluated two versions of the R 2 criterion. Finally, applications to real data are presented. The new criterion proved to be crucial to choose models taking into account the robustness of the maximum likelihood estimation procedure in the presence of influential cases.
Fractional Derivatives: The Perspective of System Theory
Authors: Duarte Ortigueira Manuel , Tenreiro Machado José
Published: February 2019

This paper addresses the present day problem of multiple proposals for operators under the umbrella of “fractional derivatives”. Several papers demonstrated that various of those “novel” definitions are incorrect. Here the classical system theory is applied to develop a unified framework to clarify this important topic in Fractional Calculus.
Monarch Butterfly Optimization for Facility Layout Design Based on a Single Loop Material Handling Path
Authors: Kim Minhee , Chae Junjae
Published: February 2019

Facility layout problems (FLPs) are concerned with the non-overlapping arrangement of facilities. The objective of many FLP-based studies is to minimize the total material handling cost between facilities, which are considered as rectangular blocks of given space. However, it is important to integrate a layout design associated with continual material flow when the system uses circulating material handling equipment. The present study proposes approaches to solve the layout design and shortest single loop material handling path. Monarch butterfly optimization (MBO), a recently-announced meta-heuristic algorithm, is applied to determine the layout configuration. A loop construction method is proposed to construct a single loop material handling path for the given layout in every MBO iteration. A slicing tree structure (STS) is used to represent the layout configuration in solution form. A total of 11 instances are tested to evaluate the algorithm’s performance. The proposed approach generates solutions as intended within a reasonable amount of time.
Convergence Theorems for Modified Inertial Viscosity Splitting Methods in Banach Spaces
Authors: Pan Chanjuan , Wang Yuanheng
Published: February 2019

In this article, we study a modified viscosity splitting method combined with inertial extrapolation for accretive operators in Banach spaces and then establish a strong convergence theorem for such iterations under some suitable assumptions on the sequences of parameters. As an application, we extend our main results to solve the convex minimization problem. Moreover, the numerical experiments are presented to support the feasibility and efficiency of the proposed method.
Kinetic Investigation of Silver Recycling by Leaching from Mechanical Pre-Treated Oxygen-Depolarized Cathodes Containing PTFE and Nickel
Authors: Schosseler Jil , Trentmann Anna , Friedrich Bernd , Hahn Klaus , Wotruba Hermann
Published: February 2019

This paper focuses on the recycling of silver from spent oxygen-depolarized cathodes through an innovative combination of pre-treatment methods and leaching. A silver- and polytetrafluorethylene (PTFE)-rich fraction was produced by cryogenic milling, screening, and magnetic separation. In order to understand the kinetic leaching mechanism, the silver-rich fraction was leached by different concentrations of nitric acid and hydrogen peroxide. Results showed that nickel influences the silver leaching. This leads to complex reaction systems, which cannot be described by the Arrhenius law.
Numerical Computation of Material Properties of Nanocrystalline Materials Utilizing Three-Dimensional Voronoi Models
Authors: Bazios Panagiotis , Tserpes Konstantinos , Pantelakis Spiros
Published: February 2019

Nanocrystalline metals have been the cause of substantial intrigue over the past two decades due to their high strength, which is highly sensitive to their microstructure. The aim of the present project is to develop a finite element two-phase model that is able to predict the elastic moduli and the yield strength of nanostructured material as functions of their microstructure. The numerical methodology uses representative volume elements (RVEs) in which the material microstructure, i.e., the grains and grain boundaries, is presented utilizing the three-dimensional (3D) Voronoi algorithm. The implementation of the 3D Voronoi particles was performed on the nanostructure investigation of ultrafine materials by SEM and TEM. Proper material properties for the grain interiors (GI) and grain boundaries (GB) were computed using the Hall-Petch equation and a dislocation-based analytical approach, respectively. The numerical outcomes show that the Young’s Modulus of nanostructured copper increased by increasing the crystallite volume fraction, while the yield strength increased by decreasing the grain size. The numerical predictions were strongly confirmed in opposition to finite element outcomes, experimental results from the open literature, and predictions from the rule of mixtures and the Mori-Tanaka analytical models.
Heterogeneous Immunoassay Using Channels and Droplets in a Digital Microfluidic Platform
Authors: Liu Yuguang , Papautsky Ian
Published: February 2019

This work presents a heterogeneous immunoassay using the integrated functionalities of a channel and droplets in a digital microfluidic (DMF) platform. Droplet functionality in DMF allows for the programmable manipulation of discrete sample and reagent droplets in the range of nanoliters. Pressure-driven channels become advantageous over droplets when sample must be washed, as the supernatant can be thoroughly removed in a convenient and rapid manner while the sample is immobilized. Herein, we demonstrate a magnetic bead-based, enzyme-linked immunosorbent assay (ELISA) using ~60 nL of human interleukin-6 (IL-6) sample. The wash buffer was introduced in the form of a wall-less virtual electrowetting channel by a syringe pump at the flow rate of 10 μL/min with ~100% bead retention rate. Critical parameters such as sample wash flow rate and bead retention rate were optimized for reliable assay results. A colorimetric readout was analyzed in the International Commission on Illumination (CIE) color space without the need for costly equipment. The concepts presented in this work are potentially applicable in rapid neonatal disease screening using a finger prick blood sample in a DMF platform.
Evaluating Metal Criticality for Low-Carbon Power Generation Technologies in Japan
Authors: Miyamoto Wataru , Kosai Shoki , Hashimoto Seiji
Published: February 2019

Given a potential increase in low-carbon power generation, assessing the criticality of metals used for its technologies is of significant importance. While several studies analyzed the metal criticality of an individual technology, the national metal criticality for a wide range of low-carbon power generation technologies and the comparison of overall criticality of each technology have yet to be fully evaluated. Therefore, this study firstly evaluates the criticality of 29 metals used in facilities for renewable energy and highly efficient thermal power generation in Japan and then compares the overall criticality for each technology to identify metals that might impose limitations on these technologies and to discuss measures for removal of factors hindering the spread of low-carbon power generation technologies. It was discovered that solar power generation technology is the most critical technology from the perspective of supply risk due to the use of indium, cadmium and selenium, while wind power generation is the most critical technology from the perspective of vulnerability to supply restriction because of the use of neodymium and dysprosium. A developed approach would have a significant potential to contributing to energy-mineral nexus, which may assist in providing policy implications from the perspectives of both specific metals and technologies.
New Rigid Polycyclic Bis(phosphane) for Asymmetric Catalysis
Authors: Pietrusiewicz K. Michał , Szwaczko Katarzyna , Mirosław Barbara , Dybała Izabela , Jasiński Radomir , Demchuk Oleg M.
Published: February 2019

A simple, highly efficient synthesis of a series of novel chiral non-racemic rigid tetracyclic phosphorus ligands, applicable in important chemical asymmetric transformations, was performed. In a tandem cross-coupling/C-H bond activation reaction, a well-recognised and readily available ligand (R,R)-NORPHOS was used as the starting material. The palladium complexes of new ligands were obtained and characterised on the example of a crystalline dichloropalladium complex of [(1R,2R,9S,10S,11R,12R)-4-phenyltetracyclo[8.2.1.02,9.03,8]trideca-3,5,7-triene-11,12-diyl]bis(diphenylphosphane). A notably high activity and stereoselectivity of the palladium catalysts based on the new ligands were confirmed in a model asymmetric allylic substitution reaction. Herein, we discuss the geometry of the palladium complexes formed and its impact on the efficiency of the catalysts. A comparison of their geometric features with other bis(phosphane) ligand complexes found in the Cambridge Structural Database and built density functional theory (DFT) commutated models is also presented and rationalised.
Simultaneous Determination of Thirteen Q-Markers in Raw and Processed Tussilago farfara L. by UPLC-QQQ-MS/MS Coupled with Chemometrics
Authors: Yang Liu , Jiang Hai , Hou Ajiao , Guo Xinyue , Man Wenjing , Yan Meiling , Xing Xudong , Yang Bingyou , Wang Qiuhong , Kuang Haixue
Published: February 2019

The purpose of this study was to establish a rapid, reliable, and sensitive ultra-performance liquid chromatography with triple-quadrupole tandem mass spectrometry coupled with chemometric method to measure and evaluate the differences between thirteen compounds in raw and processed Tussilago farfara L. from different sources. This assay method was validated, and the results indicated that the calibration curves for the thirteen compounds had good linearity (R2 > 0.9990). The limits of detection and limits of quantification of the thirteen compounds ranged from 0.0012 to 0.0095 μg/mL and from 0.0038 to 0.0316 μg/mL, respectively. The relative standard deviations (RSD) of the intra- and inter-day precisions and stability ranged from 1.06 to 2.00%, 0.26 to 1.99%, and 0.75 to 1.97%, respectively. The sample recovery rates of the thirteen compounds with different concentrations were 94.47–104.06%. The chemometric results, including principal component analysis, hierarchical clustering analysis, three-dimensional analysis, and box plot analysis, indicated that there are significance differences in raw and processed Tussilago farfara L. The results of this study confirm that the proposed method is the first reported method that has been successfully applied for simultaneous determination and discovery of the difference between thirteen compounds of raw and processed Tussilago farfara L. Thus, this method could be a helpful tool for the detection and confirmation of the quality of traditional Chinese medicines and provide a basis for future pharmacological studies.
A Survey of Assistive Technologies for Assessment and Rehabilitation of Motor Impairments in Multiple Sclerosis
Authors: Rajavenkatanarayanan Akilesh , Kanal Varun , Tsiakas Konstantinos , Calderon Diane , Papakostas Michalis , Abujelala Maher , Galib Marnim , Ford James C. , Wylie Glenn , Makedon Fillia
Published: February 2019

Multiple sclerosis (MS) is a disease that affects the central nervous system, which consists of the brain and spinal cord. Although this condition cannot be cured, proper treatment of persons with MS (PwMS) can help control and manage the relapses of several symptoms. In this survey article, we focus on the different technologies used for the assessment and rehabilitation of motor impairments for PwMS. We discuss sensor-based and robot-based solutions for monitoring, assessment and rehabilitation. Among MS symptoms, fatigue is one of the most disabling features, since PwMS may need to put significantly more intense effort toward achieving simple everyday tasks. While fatigue is a common symptom across several neurological chronic diseases, it remains poorly understood for various reasons, including subjectivity and variability among individuals. To this end, we also investigate recent methods for fatigue detection and monitoring. The result of this survey will provide both clinicians and researchers with valuable information on assessment and rehabilitation technologies for PwMS, as well as providing insights regarding fatigue and its effect on performance in daily activities for PwMS.
Microstructures and Photodegradation Performance toward Methylene Orange of Sputtering-Assisted Decoration of ZnFe2O4 Crystallites onto TiO2 Nanorods
Authors: Liang Yuan-Chang , Liu Yen-Chen
Published: February 2019

In this study, TiO2–ZnFe2O4 (ZFO) core-shell nanorods with various ZFO crystallite thicknesses were synthesized through sputtering-deposited ZFO thin films onto the surfaces of TiO2 nanorods. By coupling the ZFO narrow bandgap oxide with TiO2, an enhanced photodegradation efficiency of methylene orange under irradiation was achieved. Structural analyses revealed that ZFO crystallites fully covered the surfaces of the TiO2 nanorods. The sputtering-deposited ZFO crystallites on the head region of the composite nanorods were markedly thicker than those covering the lateral region of the composite nanorods. The coverage of ZFO crystallites on the TiO2 nanorods led to an improved light harvesting, a decrease in the hole–electron recombination rate, as well as the enhanced photodegradation activity of the TiO2–ZFO heterostructures under irradiation. The optimized ZFO thickness on the head region of the composite nanorods was approximately 43 nm on average and that at the lateral region of the composite nanorods was 15 nm, which exhibited superior photodegradation ability to methylene orange and retained a stable photodegradation efficiency of approximately 97% after cycling tests. The results herein demonstrate that sputtering deposition of ZFO crystallite with tunable thickness is a promising approach to designing TiO2–ZFO composite nanorods with various ZFO coverage sizes and to adjust their photodegradation ability toward organic dyes.
Antioxidant Nanomaterial Based on Core–Shell Silica Nanospheres with Surface-Bound Caffeic Acid: A Promising Vehicle for Oxidation-Sensitive Drugs
Authors: Arriagada Francisco , Günther Germán , Nos Jaume , Nonell Santi , Olea-Azar Claudio , Morales Javier
Published: February 2019

The design of efficient, biocompatible, and easily prepared vehicles for drug delivery is a subject of great interest for medicine and pharmaceutical sciences. To achieve the above goals, surface functionalization is critical. Here, we report a hybrid nanocarrier consisting of core–shell silica nanospheres and the antioxidant caffeic acid linked to the surface, to evaluate their in vitro antioxidant capacity, their capability to protect oxidation-sensitive compounds incorporated in nanoparticles, and to study the interaction with bovine serum albumin protein. The results show that the radical-scavenging activity of immobilized caffeic acid is attenuated in the silica nanospheres; however, other antioxidant properties such as Fe2+-chelating activity and singlet oxygen quenching are enhanced. In addition, caffeic acid is protected from binding to proteins by the nanoparticle, suggesting that this nanosystem is more likely to maintain the antioxidant activity of caffeic acid in biological media. Finally, the natural antioxidant barrier on the nanocarrier is able to delay the degradation of a compound incorporated into this nanovehicle. Considering all findings, this work proposes a suitable tool for pharmaceutical and cosmetic industries as an antioxidant nanocarrier for oxidation-sensitive drugs.