bluuebunny/crossref_metadata_2025 huggingface dataset:
South American Nothochrysinae (Neuroptera, Chrysopidae): I. Description of Nothochrysa ehrenbergi sp. nov.
Authors: Tauber Catherine A.
Published: July 2019

A new species,Nothochrysaehrenbergisp. nov., is described from Chile; it is the first species ofNothochrysato be reported from the Southern Hemisphere and only the second from the New World. The genus now contains six extant species as well as two species known from late Oligocene and Miocene fossils. An updated catalog of the validNothochrysaspecies is presented, and threenomina dubiaare discussed. The inclusion of the new species inNothochrysais well supported by morphological features. However, it and other species currently in the genus also share significant features withArchaeochrysa, an older genus of Nothochrysinae which is known only from the Eocene (Ypresian) to the late Oligocene. It therefore appears thatN.ehrenbergiis among the least derivedNothochrysaspecies, and that the separation ofArchaeochrysafromNothochrysais open to question and further examination.
Measuring Student Perceptions of Clinical Competence
Authors: Clark Michele C. , Owen Steven V. , Tholcken Michele A.
Published: July 2019

In a large, southwestern, Gulf coast school of nursing, the faculty sought additional information to enhance their clinical evaluations of students. To gather such information, the faculty developed a rapid and psychometrically sound evaluation tool that elicited students' self-efficacy beliefs for newly learned clinical skills, and the perceived importance of the clinical skills they were mastering. The Self-Efficacy for Clinical Evaluation Scale (SECS) is a 30-item, dual-response scale that demonstrates strong psychometric properties. Scores on the SECS help faculty identify skills or content areas that students feel little confidence in using, even when students value those skills or content as very important. These insights are assisting course leaders in tailoring the course structure and teaching strategies to better meet students' educational and practice needs.
Crystallization kinetics of safflower and olive oils during low-temperature storage
Authors: Yoshida M. , Miyagawa Y. , Fujita H. , Adachi S.
Published: July 2019

The crystallization behaviors of safflower and olive oils were investigated according to changes in volume and transmitted light intensity during isothermal storage at low temperature. The changes between the oils were significantly different even though their fatty acid compositions were similar, with oleic acid accounting for more than 75% (w/w) of the total oil. It was expected that minor components with high melting points would affect the crystallization behaviors of these oils. The crystallization processes of the oils were then analyzed using a kinetic model in which the oil crystallizes through two different processes. It is suggested that although the crystallization behaviors were apparently different, the crystallization mechanisms of these oils are essentially the same.
Characterization of different ozonized sunflower oils I. Chemical changes during ozonization
Authors: Ledea-Lozano O. E. , Fernández-García L. A. , Gil-Ibarra D. , Tena N. , Garcés R. , Martínez-Force E. , Salas J. J.
Published: July 2019

Vegetable oils are usually rich in unsaturated fatty acids which are susceptible to oxidation. The oxidation of vegetable oils has been one of the most widely studied fields within lipid chemistry, because it alters their properties and nutritive value, inducing the formation of harmful compounds and off-flavors. Moreover, oxidized vegetable oils display altered physical and chemical properties which are conferred by the newer oxygenated compounds they contain. This is the case of ozonized oils. Ozone is a powerful oxidizing agent that mainly acts on olefinic compounds which generate ozonides and other peroxidic species that can decompose into carbonilic fragments. The action of the oxidant and the later reactions depend on the chemical environment of the reaction as well as the carbonyl termination products resulting from peroxide cleavage. In recent years, sunflower oils with different fatty acid compositions have been developed by breeding and mutagenesis. They displayed higher contents of oleic, stearic or palmitic acids, which mainly alters their triacylglycerol composition. Therefore, four different sunflower oils, common, high oleic, high stearic-high oleic and high palmitic-high oleic, were oxidized with ozone and the progress of the reaction was monitored by measuring the level of oil peroxygenation and the changes in the oils’ fatty acid compositions. The peroxidated species formed during ozonation were studied by FT-IR spectroscopy. The main conclusions of this work were that ozonation caused linear oxidation rates that were similar in all the oils assayed. The addition of water accelerated oxidation, which tended to occur in linoleic polyunsaturated fatty acid The FT-IR pointed to the presence of ozonide-derived peroxides as the major oxygenated species.
Model of Alumina Coating Microstructure Developed on the Base of Electrical Insulation Properties
Authors: Ulianitsky Vladimir Yu. , Shtertser Alexandr , Batraev Igor
Published: July 2019

On the CCDS2000 installation, detonation spraying of coatings from M28 and METCO 6103 aluminum oxide powders on steel substrates was carried out, and the dependence of the electrical resistivity of coatings on the atmosphere humidity was studied. It is shown that when the relative humidity changes from 14 to 80%, the specific electrical resistance of the coating decreases by 2-3 orders of magnitude from ρ ˃1013 Ω·cm to ρ ≈ 1011 Ω·cm. On the base of obtained data, the model of coating microstructure is proposed, according to which alumina layer contained through defects in a form of nanochannels with diameter in the range 1-10 nanometers. In a coating cross section, the area of nanochannels sums up to 1%. In presence of high atmospheric humidity, these nanochannels can be filled with absorbed water, increasing drasticcaly the coating electrical conductivity.
Laser Assisted High Entropy Alloy Coating on Low Carbon Steel
Authors: Souto Carlos Alberto , da Silva Gustavo Faria Melo , Rodriguez Laura Angelica Ardila , de Oliveira Aline C. , Cardoso Kátia Regina
Published: July 2019

Coatings with high entropy alloys of the AlCoCrFeNiV system were obtained by selective laser melting on low carbon steel substrates. The effect of the variation of the Fe and V contents as well as the laser processing parameters in the development of the coating were evaluated. The coatings were obtained from the simple powder mixtures of the high purity elemental components in a planetary ball mill. The coatings were obtained by using CO2laser with a power of 100 W, diameter of 0.16 mm, and scan speed varying from 3 to 12 mm/s. Phase constituents, microstructure and hardness were investigated by XRD, SEM, and microhardness tester, respectively. Wear resistance measurements were carried out by the micro-abrasion method using ball-cratering tests. The coatings presented good adhesion to the substrate and high hardness, of the order of 480 to 650 HV. Most homogeneous coating with nominal composition was obtained by using the higher scan speed, 12 mm/s. Vanadium addition increased hardness and gave rise to a high entropy alloy coating composed by BCC solid solutions. Ball cratering tests conducted on HEA layer showing improvement of material wear resistance, when compared to base substrate, decreasing up to 88% its wear rate, from 1.91x10-6mm3/Nmm to 0.23x10-6mm3/Nmm.
Ethylene Oxide Sterilization of TiN/TiO2 Coated Titanium Implant Material
Authors: Nikolova Maria P. , Nikolov Vesselin , Valkov Stefan , Yankov Emil , Zaharieva Vanya , Petrov Peter
Published: July 2019

The goal of this work is to evaluate a common final sterilization technique with EtO by measuring its effect on the physicochemical properties of PVD deposited TiN/TiO2 coatings on Ti-5Al-4V alloy. As the effectiveness of EtO sterilization corresponds to the operation parameters (temperature, duration, humidity, etc.), two different exposure cycles (cool (MS) at 37 °C for 220 min gas expose and warm (SS) at 55 °C for 100 min expose) were examined. SEM analysis revealed that the surface morphology of the coatings was not changed after both MS and SS treatments. In contrast to Ti 2p and O 1s peaks determined by XPS analysis, C 1s peak of TiO2 layer decreased with increasing sterilization temperature while the percentage contribution of Ti-OH in O 1s increased. This affected the surface hydrophilicity and free energy that increased from 47.37 for the control sample to 50.77 mJ m-2 in the case of SS specimen. Additionally, EtO sterilized samples demonstrated decreased values of corrosion and passivation current densities in simulated body fluid (pH 7.4) at 37 ± 0.05 °C as opposed to the control sample. The results indicate the suitability of both mild and severe EtO sterilization methods for improvement of the desired physicochemical properties of gradient TiN/TiO2 coatings.
Optimization of Microstructural Evolution during Laser Cladding of Ni Based Powder on GCI Glass Molds
Authors: Bourahima Fazati , Helbert Anne Laure , Ji Vincent , Rege Michel , Courteaux Arnaud , Brisset François , Baudin Thierry
Published: July 2019

In glass industry, laser cladding is an innovative surfacing technique allowing to deposit a layer of nickel to protect glass mold against corrosion, abrasion and thermal fatigue. This method (powder fusion by projection), well known in additive manufacturing represents a real technological leap for the glass industry. But during laser cladding of Ni-based powder on gray cast iron, cracks can be observed for some process conditions. These cracks are often due to the Heat Affected Zone that creates structural stresses linked to the development of a martensitic structure in the ferritic matrix of the lamellar graphite cast iron. The aim of this work is to observe the impact of laser cladding (without substrate pre-heating usually employed to limit cracking) on the coating behavior but also on the flake-graphite cast iron substrates. The microstructure and the mechanical properties were studied (SEM and microanalysis, microhardness) around the interface cladding/substrate. Also, the impact of the processing parameters (power P (1500-2300 W), scanning speed v (2.5-10 mm/s) and powder feeding rate PFR (24.5-32.5 g/min) was studied by using the ANOVA (ANalysis Of VAriance) technique. It has been observed that laser cladding on graphite cast iron is possible without cracks by limiting the linear energy induced by the process. Also, an optimization of the processing parameters (P, v, PFR) in order to obtain the industrial expected geometry of the coating has been proposed.
Improvement of Hydrophobic Property of Stainless-Steel Plates by Forming Lens-Like Protrusions Similar to Oxalis Leaf Surfaces
Authors: Horiuchi Toshiyuki , Imon Yoshie , Sumimoto Kazuya , Yanagida Akira , Kobayashi Hiroshi
Published: July 2019

Leaves of an obscure plant “oxalis deppei” are so hydrophobic that showered water droplets are almost completely repelled and hardly remained on their surfaces. For this reason, surface configurations were investigated. On the live leaves, there formed protrusions somewhat similar to those observed on lotus leaves which are well known as super hydrophobic leaves. However, in winter, it was found that even dead leaves were hydrophobic also. Because leaf tissues were shriveled and dried half, heights of protrusions with sizes of 20-50 μm were low, and undulations of surfaces were gentle and smooth, and pitches of undulations were as large as 30-70 μm. It was thought that such gentle lens-like protrusions would be probably formed on versatile stainless-steel plates using lithography and wet chemical etching. For this reason, arrays of protrusions with a size of 20 μm, a pitch of 35 μm, and heights of 6-7 μm were formed, and change of hydrophobic properties were investigated. As a result, the hydrophobic properties were effectively improved by forming even such gentle and smooth protrusions. It was also clarified that contact angles were improved almost in proportion to etched depths.
Improving the Surface Finish and other Properties of Engineering Metal Parts
Authors: Obeidi Muhannad A. , McCarthy Eanna , Ul Ahad Inam , Brabazon Dermot
Published: July 2019

The manufacture of metal parts requires post processing in most cases. These processes include heat treatment for releasing of the residual stresses resulting on the metal surface due to the excessive mechanical forces applies to cut the metal during machining, i.e. milling, turning and drilling. Another example would be the polishing of parts using different techniques. In predominant, polishing is used enhance the part’s roughness to improve the friction coefficient, to give the parts a better view and most important is to adjust the final dimensional accuracy in the microns and sub-microns scale. Traditional polishing methods include the mechanical polishing by using abrasive media or grinding machines, chemical polishing which has the benefit of reaching the inaccessible features although this method requires longer processing time in addition to the impact on environment. Sometimes the thermal deburring method is also applied for the chamfer of sharp edges and corners. In the recent years, the laser polishing technique exhibits interesting efforts and results regarding reproducibility, high control over the processing parameters which allow for the processing of different metals and non-metals materials in addition to the ultrashort processing time. This study is focusing on the laser surface polishing of metal parts, its potentials and limitations. In this study, laser surface polishing using CO2 laser beam irradiation was implemented on stainless steel Additive Manufactured produced surfaces. Two design of experiment models were implemented for the optimization of the main laser input processing parameters. The processing parameters examined were the laser beam power, the scanning speed, the number of laser scan passes, the percentage overlap of the laser tracks between the consecutive passes and the laser beam focal position. The characterization of the measured surface roughness and the modified layer microstructure were carried out using scanning electron microscopy (SEM) and 3D optical.
Study of the FDM Parameters of the ABS Parts in the Surface Quality after Machining Operations
Authors: Del Sol Irene , Domínguez Calvo Álvaro , Piñero David , Salguero Jorge , Batista Moises
Published: July 2019

Additive Manufacturing (AM) is one of the Key Enabling Technologies (KET’s) in Industry 4.0. One of the most worldwide used technologies is Fussed Deposition Modelling (FDM), a technology commonly used for domestic purposes. However, it could become a profitable option for industrial applications such as protections parts, flexible clamping systems or large volume parts. One of the issues that keeps this technology away from the mainstream industry is the lack of dimensional accuracy and the appearance of layer deposition defects that are produced as a consequence of the nature of the process. Those defects are usually reduced using chemicals post treatments. However, this option considerably increases the cost of the part as well as it environmental impact for big size parts. This work studied machining procedures as sustainable post-operation in order to reduce FDM dimensional and superficial defects. For this purpose, Acrylonitrile-Butadiene-Styrene (ABS) parts produced by FDM were machined using different machining strategies. Parts were perimetral milled using up milling and down milling strategies and finally a face milling operation was performed. The relationship between the layer height and the directionality of the layers in machining results was analyzed, in terms of surface quality (Ra, Rz, Rsm) and dimensional accuracy. Rz and Rsm results had been analyzed to verify that the grooves produced in FDM process disappeared. Ra values were reduced by up to ten times after milling process. Dimensional accuracy is increased by up to 50% while the removed rate was kept in a maximum of 7%. Additionally, removed material can be reused by means of proper chip extraction system, favoring the performance of the resources.
Air-Cooling Influence on Wire Arc Additive Manufactured Surfaces
Authors: Hackenhaar William , Montevecchi Filippo , Scippa Antonio , Campatelli Gianni
Published: July 2019

WAAM (Wire-Arc-Additive-Manufacturing) is an additive manufacturing process which uses arc welding to produce metal parts. This process is prone to heat accumulation, i.e. a progressive increase of the interlayer temperature and molten pool size, having detrimental consequences on the material properties and on the workpiece integrity. This paper investigates the effect of air jet impingement, an active cooling technique, to prevent heat accumulation, on the surfaces of WAAM workpieces. A reference test case was manufactured using traditional free convection cooling and air jet impingement. The workpiece temperature was measured using Ktype thermocouples. The manufactured surfaces were measured using a coordinate measuring machine and compared in terms of deposition efficiency, deposit height and average arithmetical deviation. The temperature results highlight that air jet impingement is effective in preventing the occurrence of heat accumulation. The surface data highlight that air jet impingement increase the deposited height and the surface waviness with a consequent decrease of the deposition efficiency.
Experimental Study of Functionalized Polymer Matrix Composite with Multi-Material Metal Coatings Produced by Means of Cold Spray Technology
Authors: Perna Alessia Serena , Viscusi Antonio , Astarita Antonello , Boccarusso Luca , Caraviello Antonio , Carrino Luigi , Durante Massimo , Sansone Raffaele
Published: July 2019

In this activity, customized panels for the CS deposition have been produced and aluminium has been deposited using air as a carrier gas. The custom-made panels were made with different matrix thicknesses on the surface in order to point out the influence of the fibres in the deposition and to study the feasibility and the growth of the coating. The polymer chosen for the matrix is polypropylene, widely used in the automotive sector, while for the reinforcements glass fibres have been used. Different process parameters have been examined in order to point out the influence of temperature, stand-off distance and pressure chosen, on the compaction and densification of the coating produced. In addition, morphological investigations were performed to further characterize the coatings deposited. It has been noticed that aluminium powders can be effectively deposited on polypropylene panels, leading to significantly better results when the thickness of the matrix is ​​sufficient to prevent the powders bouncing elastically on the fibres, while benefiting from the stiffening effect of the latter.
Osteoblast Cell Response to LIPSS-Modified Ti-Implants
Authors: Orazi Leonardo , Pogorielov Maksym , Deineka Volodumyr , Husak Evhenia , Korniienko Victoriia , Mishchenko Oleg , Reggiani Barbara
Published: July 2019

In the present work, the surface of Ti-6Al-7Nb samples was patterned with Laser Induced Periodic Surface Structures in order to improve biocompatibility, increase tissue ingrowth and decrease bacterial adhesion and inflammatory response for applications in dental and orthopedic implants. Polished and sandblasted disks 10 mm in diameter were treated generating LIPSS under two different sets of parameters. The surface morphology and chemistry were investigated both by secondary electrons imaging, EDS analysis and Atomic Force Microscopy. Primary rat osteoblast culture (passage 2) was used to assess cell toxicity and biocompatibility. Alamar Blue assay was used to access cell viability and proliferation on day 1, 3 and 7. The difference between cell adhesion on polished and sandblasted surface as well as between polished and LIPSS-modified surface are described and discussed.
Comparison of Tribological Behaviour between Natural and Synthetic Fibres Composites
Authors: de Fazio Dario , Boccarusso Luca , Durante Massimo
Published: July 2019

This work aims to study the wear resistance of composite materials that mainly differ in the fibre typologies used as reinforcement. In detail hemp, glass and carbon fibres in form of woven fabric were used. For the production of the composite materials, an epoxy resin was used as matrix, and the vacuum infusion process was adopted. In order to compare the tribological behaviour of the manufactured composites, a detailed experimental campaign, including tribological tests and microgeometrical measurements, was carried out. In particular, the tribological behaviour was studied through the pin-on-disk tests conducted at 210 mm/s as peripheral speed under 50 N as applied load testing both the composite and the single un-impregnated fabrics. These tests were followed by microgeometrical measurements in order to critically observe the wear tracks, evaluate their depth, width and volume and then to calculate the final less of volume. The tests results showed a good and interesting behaviour of composite materials reinforced with hemp fibres.
Effects of Surface Treatments on the Fatigue Response of High Strength Fasteners
Authors: Reggiani Barbara , Olmi Giorgio , Orazi Leonardo , Tomesani Luca , Fini Stefano , Barozzi Lorenzo , Pelaccia Riccardo , Bandini Michele
Published: July 2019

The aim of the present work was the assessment of the impact of deep-rolling and shot-peening performed in the underhead and in the unthreaded shank of two high strength screws (36 NiCrMo and 42 CrMoV) for fatigue life enhancement. The experimental campaign consisted of six combinations, including the non-treated state. The aforementioned treatments were evaluated alone or with shot-peening performed after deep-rolling in the underhead fillet of the screws. Deep rolling was carried out at the optimal rolling force, whereas two shot diameters were considered for shot-peening (Z100 and UFS70). The results have been evaluated in terms of fatigue limits and factor effects have been assessed by marginal mean plots.
A Finite Elements Study on Porosity Creation Mechanisms in Cold Sprayed Coatings
Authors: Weiller Sebastien , Delloro Francesco , Lomonaco Patrizio , Jeandin Michel , Garion Cédric
Published: July 2019

Porosity is a crucial property in cold sprayed coatings. If it can be beneficial for certain applications,e.g.lubricated contacts in tribology, it is generally detrimental for mechanical and anti-corrosion properties and for gas tightness of the coating. It is thus important to understand what are the process variables affecting coating porosity and quantify their effects. However, at present day, the experimental observation of cold spray coating build up and porosity creation mechanisms is far from achievable. In this study, a Coupled Eulerian Lagrangian (CEL) numerical 3D finite element analysis of single and multi-particle impacts was led to understand the mechanisms involved in the creation of porosity. All simulations were carried out on Abaqus/Explicit v6.14. Single particle impact simulations addressed the influence of mesh size, particle temperature, size and speed on particle temperature and equivalent plastic deformation after impact. Jetting phenomena appeared and their relationship to the mesh size was established. Nevertheless, the porosity creation mechanisms seemed to arise within the more complex context of multiple particle interactions at impact. For this reason, multiparticle impact simulations were carried out, based on experimental powder granulometry distributions and particle in-flight velocity measurements. Porosity in these simulations was quantified by computing the successive layered convex hulls of the particle cluster after impact. Individual particles were also tracked during the simulations, in order to understand the porosity creation mechanisms. Finally, those porosity rates were compared to those experimentally measured in 2D by SEM image analysis.
Effect of Optimized Heat Treatments on the Tensile Behavior and Residual Stresses of Selective Laser Melted AlSi10Mg Samples
Authors: Colombo Chiara , Biffi Carlo Alberto , Fiocchi Jacopo , Tuissi Ausonio , Vergani Laura
Published: July 2019

The use of additive manufacturing (AM) technique is recently increased due to its ability in producing complex-shaped components. AlSi10Mg alloy is largely employed for AM and, in particular, for selective laser melting (SLM). Hence, the interest on this alloy is growing, together with the studies to control its mechanical performances, which can be increased by microstructure modification. With this focus, low temperature heat treatments to enhance AlSi10Mg mechanical behavior have been proposed in the recent literature. The present work focuses on two post-additive thermal treatments, with temperatures specifically selected for SLMed AlSi10Mg alloy. The study investigates their effect on mechanical performances, with a particular attention to residual stresses. Experimental measurements of residual stresses obtained by an X-ray diffractometer (XRD) are presented, considering samples produced with their main dimension along the in-plane scanning directions (XY configuration) and the Z direction. Different conditions are accounted: 1) as-built; 2) after heat treatment at 244°C for 180 minutes; 3) after heat treatment at 290°C for 45 minutes. Tensile properties are correlated with the measurements of the residual stresses, allowing for a critical discussion and for a deeper insight on the correlation of the mechanical performance with the process parameters and the following thermal treatments.
Set-Up of an Experimental Procedure for the Surface Smoothing of FDM Parts through Acetone Vapor
Authors: Coppola Antonio , Impero Filomena , Ruggiero Cuono , Scala Fabrizio , Squillace Antonino
Published: July 2019

Fused deposition modeling (FDM) is an additive manufacturing technology where three-dimensional physical models are manufactured by layer-by-layer deposition. However, the layered surface built with FDM suffers from poor surface quality and dimensional accuracy even for basic part geometries. This proves to be unacceptable and not satisfactory for most general purposes with the consequence of a decreased value of the final product. Several methods for post-processing were proposed to achieve fine surface of manufactured components. In particular, for components manufactured with polylactic acid (PLA) the chemical post-processing with dimethyl ketone (acetone), named vapor smoothing process, seems to be very promising to significantly improve the surface roughness. Moreover, acetone has the main advantage to have a low cost, low toxicity and high diffusion rate. However, this polishing procedure may dissolve the outer surface of the parts affecting the structural reliability of the part. In this work, a novel device, consisting of a cylindrical chamber in Pyrex, is set-up for the vapor smoothing process with acetone. The system is designed to permit the injection of a gas containing acetone at different concentrations and at different operating conditions (temperature, contact time). The samples used for the test are truncheon design manufactured using different printer settings; each truncheon is built at inclination angles varying from 0° to 45° in step of 5°. The variation of the surface roughness was investigated using a confocal microscope Leica DCM3D, equipped with the software LeicaScan and LeicaMap.
Influence of Processing Parameters on the Local Scratch Resistance of Cold Sprayed Ti6Al4V Coatings
Authors: Sirvent Paloma , Garrido-Maneiro Miguel Ángel , Poza Pedro
Published: July 2019

Ti6Al4V coatings were cold sprayed onto the same bulk alloy at standard conditions, using 800 °C as gas temperature, and a set of new conditions, using 1100°C as gas temperature, which improved coatings performance. Some of these coatings, processed with innovative parameters, were heat treated to promote adhesion and reduce porosity. Scratch tests were performed using a nanoindenter Agilent G200 and the effect of both normal load and scratch velocity were explored. The different mechanisms responsible of wear were evaluated, identifying ploughing and cutting as the main abrasion mechanisms. The wear rate measured in the standard coating was the highest, indicating that this material could not be used to repair the bulk component. However, the abrasion resistance measured in the coatings sprayed at 1100°C was similar to that found in the bulk substrate. Therefore, cold spray could be used for repairing using the new conditions evaluated in this work.
Integrin Binding to the Trimeric Interface of CD40L Plays a Critical Role in CD40/CD40L Signaling
Authors: Takada Yoko K. , Yu Jessica , Shimoda Michiko , Takada Yoshikazu
Published: July 2019

CD40L plays a major role in immune response and is a major therapeutic target for inflammation. Integrin α5β1 and CD40 simultaneously bind to CD40L. It is unclear if α5β1 and CD40 work together in CD40/CD40L signaling or how α5β1 binds to CD40L. In this article, we describe that the integrin-binding site of human CD40L is predicted to be located in the trimeric interface by docking simulation. Mutations in the predicted integrin-binding site markedly reduced the binding of α5β1 to CD40L. Several CD40L mutants defective in integrin binding were defective in NF-κB activation and B cell activation and suppressed CD40L signaling induced by wild-type CD40L; however, they still bound to CD40. These findings suggest that integrin α5β1 binds to monomeric CD40L through the binding site in the trimeric interface of CD40L, and this plays a critical role in CD40/CD40L signaling. Integrin αvβ3, a widely distributed vascular integrin, bound to CD40L in a KGD-independent manner, suggesting that αvβ3 is a new CD40L receptor. Several missense mutations in CD40L that induce immunodeficiency with hyper-IgM syndrome type 1 (HIGM1) are clustered in the integrin-binding site of the trimeric interface. These HIGM1 CD40L mutants were defective in binding to α5β1 and αvβ3 (but not to CD40), suggesting that the defect in integrin binding may be a causal factor of HIGM1. These findings suggest that α5β1 and αvβ3 bind to the overlapping binding site in the trimeric interface of monomeric CD40L and generate integrin-CD40L-CD40 ternary complex. CD40L mutants defective in integrins have potential as antagonists of CD40/CD40L signaling.
MD-2 Homologue Recognizes the White Spot Syndrome Virus Lipid Component and Induces Antiviral Molecule Expression in Shrimp
Authors: Gao Jie , Wang Jin-Xing , Wang Xian-Wei
Published: July 2019

The myeloid differentiation factor 2 (MD-2)–related lipid-recognition (ML) domain is found in multiple proteins, including MD-2, MD-1, Niemann–Pick disease type C2, and mite major allergen proteins. The significance of ML proteins in antibacterial signal transduction and in lipid metabolism has been well studied. However, their function in host–virus interaction remains poorly understood. In the current study, we found that the ML protein family is involved in resistance against white spot syndrome virus in kuruma shrimp, Marsupenaeus japonicus. One member, which showed a high similarity to mammalian MD-2/MD-1 and was designated as ML1, participated in the antiviral response by recognizing cholesta-3,5-diene (CD), a lipid component of the white spot syndrome virus envelope. After recognizing CD, ML1 induced the translocation of Rel family NF-κB transcription factor Dorsal into the nucleus, resulting in the expression of Vago, an IFN-like antiviral cytokine in arthropods. Overall, this study revealed the significance of an MD-2 homologue as an immune recognition protein for virus lipids. The identification and characterization of CD–ML1–Dorsal–Vago signaling provided new insights into invertebrate antiviral immunity.
A Pervasive Sensing Approach to Automatic Assessment of Trunk Coordination Using Mobile Devices
Authors: Liang Zilu , Yoshida Yasuyuki , Iino Nami , Nishimura Takuichi , Alberto Chapa-Martell Mario , Nishimura Satoshi
Published: July 2019

Assessing trunk coordination has many potential applications in health promotion. However, traditional bio-mechanical approaches are not suited for daily use as they require expensive devices and manual analysis. This study aimed to develop an approach for automatic classification of good and poor trunk coordination using widely available mobile devices. We investigated different combinations of sensor locations (i.e. chest and pelvis), sensing modalities (i.e. accelerometer and gyroscope) and classification techniques (i.e. SVM, KNN, and decision tree). Results showed that using both sensing modalities at chest and pelvis with SVM produced the best classification accuracy: 96% for chest rotation and 100% for pelvis rotation. In practice, however, using one device with both sensing modalities (i.e. accelerometer and gyroscope) will achieve a better trade-off between feasibility and accuracy. In this case, the device should be fixed on the chest. KNN should be selected as the classification technique for chest rotation (best accuracy 95%), and SVM should be selected as the classification technique for pelvis rotation (best accuracy 79%). Post hoc analysis found that poor coordination during chest rotation was associated to weak cross-correlation of angular velocity between chest and pelvis in the frontal plane, while poor coordination during pelvis rotation was associated to weak correlations of angular velocity between the three orthogonal components at chest. This study demonstrated how simple mobile devices can capture relevant motion data and extract key features that help construct computational models for automatic assessment of trunk coordination.
Bounded Depth Ascending HNN Extensions and -Semistability at infinity
Authors: Mihalik Michael L.
Published: July 2019

A well-known conjecture is that all finitely presented groups have semistable fundamental groups at infinity. A class of groups whose members have not been shown to be semistable at infinity is the class ${\mathcal{A}}$ of finitely presented groups that are ascending HNN-extensions with finitely generated base. The class ${\mathcal{A}}$ naturally partitions into two non-empty subclasses, those that have “bounded” and “unbounded” depth. Using new methods introduced in a companion paper we show those of bounded depth have semistable fundamental group at infinity. Ascending HNN extensions produced by Ol’shanskii–Sapir and Grigorchuk (for other reasons), and once considered potential non-semistable examples are shown to have bounded depth. Finally, we devise a technique for producing explicit examples with unbounded depth. These examples are perhaps the best candidates to date in the search for a group with non-semistable fundamental group at infinity.
A general thermodynamical model for adhesive frictional contacts between viscoelastic or poro-viscoelastic bodies at small strains
Authors: Roubíček Tomáš
Published: July 2019

A general model covering a large variety of the so-called adhesive or cohesive, possibly also frictional, contact interfaces between visco-elastic bodies with inertia considered in a thermodynamical context is presented. A semi-implicit time discretisation which conserves energy, is numerically stable and convergent, and which advantageously decouples the system is devised. An extension to porous media with adhesive contact influenced by a diffusant concentration is devised, too.
Large time behavior of a two phase extension of the porous medium equation
Authors: Ait Hammou Oulhaj Ahmed , Cancès Clément , Chainais-Hillairet Claire , Laurençot Philippe
Published: July 2019

We study the large time behavior of the solutions to a two phase extension of the porous medium equation, which models the so-called seawater intrusion problem. The goal is to identify the self-similar solutions that correspond to steady states of a rescaled version of the problem. We fully characterize the unique steady states that are identified as minimizers of a convex energy and shown to be radially symmetric. Moreover, we prove the convergence of the solution to the time-dependent model towards the unique stationary state as time goes to infinity. We finally provide numerical illustrations of the stationary states and we exhibit numerical convergence rates.
Non-transversal intersection of the free and fixed boundary in the mean-field theory of superconductivity
Authors: Indrei Emanuel
Published: July 2019

Non-transversal intersection of the free and fixed boundary is shown to hold and a classification of blow-up solutions is given for obstacle problems generated by fully nonlinear uniformly elliptic operators in two dimensions which appear in the mean-field theory of superconducting vortices.
Groups of Extended Affine Lie Type
Authors: Azam Saeid , Farahmand Parsa Amir
Published: July 2019

We construct certain Steinberg groups associated to extended affine Lie algebras and their root systems. Then by the integration methods of Kac and Peterson for integrable Lie algebras, we associate a group to every tame extended affine Lie algebra. Afterwards, we show that the extended affine Weyl group of the ground Lie algebra can be recovered as a quotient group of two subgroups of the group associated to the underlying algebra similar to Kac–Moody groups.
Absolute Schauder Decompositions and Linearization of Holomorphic Mappings of Bounded Type
Authors: Botelho Geraldo , Fávaro Vinícius V. , Mujica Jorge
Published: July 2019

This paper has a twofold purpose: (i) to prove that the linearization of a holomorphic function of bounded type can be represented by means of the linearizations of its derivatives; (ii) to characterize when the identity operator on the predual

G_b(U)

of the space of holomorphic functions of bounded type on a balanced open subset

U

of a Banach space belongs to a given closed operator ideal. These two results rely on the existence of an

\cal S

-absolute Schauder decomposition for

G_b(U)

.
Multiplicity of bounded solutions to the $k$-Hessian equation with a Matukuma-type source
Authors: Miyamoto Yasuhito , Sánchez Justino , Vergara Vicente
Published: July 2019

The aim of this paper is to deal with the

k

-Hessian counterpart of the Laplace equation involving a nonlinearity studied by Matukuma. Namely, our model is the problem

(1)\quad\begin{cases} S_k(D^2u)= \lambda \,\frac{|x|^{\mu-2}}{(1+|x|^2)^{{\mu}/{2}}} \,(1-u)^q &\text{in } B,\\ u < 0 & \text{in } B,\\ u=0 &\text{on }\partial B, \end{cases}

where

B

denotes the unit ball in

\mathbb{R}^n

,

n > 2k

(

k\in\mathbb{N}

),

\lambda > 0

is an additional parameter,

q > k

and

\mu\geq 2

. In this setting, through a transformation recently introduced by two of the authors that reduces problem (1) to a non-autonomous two-dimensional generalized Lotka–Volterra system, we prove the existence and multiplicity of solutions for the above problem combining dynamical-systems tools, the intersection number between a regular and a singular solution and the super and subsolution method.
Notions of Dirichlet problem for functions of least gradient in metric measure spaces
Authors: Korte Riikka , Lahti Panu , Li Xining , Shanmugalingam Nageswari
Published: July 2019

We study two notions of Dirichlet problem associated with BV energy minimizers (also called functions of least gradient) in bounded domains in metric measure spaces whose measure is doubling and supports a (1, 1)-Poincaré inequality. Since one of the two notions is not amenable to the direct method of the calculus of variations, we construct, based on an approach of Juutinen and Mazón-Rossi–De León, solutions by considering the Dirichlet problem for

p

-harmonic functions,

p > 1

, and letting

p \to 1

. Tools developed and used in this paper include the inner perimeter measure of a domain.
The arithmetic Kuznetsov formula on GL(3), I: The Whittaker case
Authors: Buttcane Jack
Published: July 2019

The original formulae of Kuznetsov for SL(2,

\mathbb Z

) allowed one to study either a spectral average via Kloosterman sums or to study an average of Kloosterman sums via a spectral interpretation. In previous papers, we have developed the spectral Kuznetsov formulae at the minimal weights for SL(3, Z), and in these formulae, the big-cell Kloosterman sums occur with weight functions attached to four different integral kernels, according to the choice of signs of the indices. These correspond to the

J

- and

K

-Bessel functions in the case of GL(2). In this paper, we demonstrate a linear combination of the spherical and weight-one SL(3,

\mathbb Z

) Kuznetsov formulae that isolates one particular integral kernel, which is the spherical GL(3) Whittaker function. Using the known inversion formula of Wallach, we give the first arithmetic Kuznetsov formula for SL(3,

\mathbb Z

) and use it to study smooth averages and the Kloosterman zeta function attached to this particular choice of signs.
A fundamental differential system of Riemannian geometry
Authors: Albuquerque Rui
Published: July 2019

We discover a fundamental exterior differential system of Riemannian geometry; indeed, an intrinsic and invariant global system of differential forms of degree

n

associated to any given oriented Riemannian manifold

M

of dimension

n + 1

. The framework is that of the tangent sphere bundle of

M

. We generalise to a Riemannian setting some results from the theory of hypersurfaces in flat Euclidean space. We give new applications and examples of the associated Euler–Lagrange differential systems.
Предельная теорема для надкритического ветвящегося блуждания с источниками различной интенсивности
Authors: Khristolyubov Ivan , Yarovaya Elena Borisovna
Published: July 2019

Рассматривается надкритическое симметричное ветвящееся случайное блуждание по многомерной решетке с непрерывным временем и конечным числом источников генерации частиц различной интенсивности без ограничения на дисперсию скачков случайного блуждания, лежащего в основе процесса. Предполагается, что спектр эволюционного оператора средних численностей частиц содержат хотя бы одно положительное собственное значение. Доказано, что при этом старшее положительное собственное значение является простым и определяет экспоненциальный рост численностей частиц как в каждом узле решетки, так и на всей решетке.
Отражающиеся процессы Леви и порождаемые ими семейства линейных операторов
Authors: Ibragimov Il'dar Abdullovich , Smorodina Natal'ya Vasil'evna , Faddeev Mikhail Mikhailovich
Published: July 2019

В работе рассматриваются одномерные марковские процессы специального вида, которые являются процессами Леви, принимающими значения на конечном интервале и отражающимися от граничных точек. Показано, что в этом случае кроме стандартной полугруппы операторов, порожденных марковским процессом, возникает еще семейство "граничных" случайных операторов, переводящих функции, заданные на границе интервала, в элементы пространства $L_2$ на всем интервале. В случае, когда исходный процесс является винеровским, эти операторы выражаются через локальное время процесса на границе интервала.
The Arusha Protocol on plant varieties protection: balancing breeders' and farmers' rights for food security in Africa
Authors: Kabau Tom , Cheruiyot Faith
Published: July 2019

The adoption of the Arusha Protocol for the Protection of New Varieties of Plants (Arusha Protocol) in 2015 created a harmonized regional legal mechanism for the protection of plant breeders’ rights (PBRs) in the African Regional Intellectual Property Organization (ARIPO) member states. Regrettably, the Arusha Protocol, which is to enter into force after the requisite ratifications, reaffirms the often criticized International Convention for the Protection of New Varieties of Plants of 1991 (UPOV 1991) in its extensive limitation of the traditional farmers’ rights to freely save, replant and exchange seeds of protected plant varieties, while liberally conceptualizing PBRs. The stated farmers’ rights are essential for the food security of the developing ARIPO member states, as their agriculture is predominantly characterized by impoverished small-scale farmers who rely on informal seed exchanges. On that basis, this article is premised on the view that the legal regime for plant varieties protection established under the Arusha Protocol is inappropriate for ARIPO members as it fails to balance breeders’ and farmers’ rights in a manner that promotes food security. It proceeds to evaluate the appropriate approach that can suitably balance breeders’ and farmers’ rights for the purposes of promoting food security in Africa.
Illegal copyright works and the remedial discretion of the court
Authors: McCutcheon Jani , Leahy Jordan
Published: July 2019

Copyright works are frequently created in breach of one or more laws. These works vary in degrees of wrongfulness and the laws and interests that are impacted by them. The works may contain illegal content, such as child pornography. Laws may also be contravened in the process of creating copyright material, such as a graffiti artist committing trespass. Courts’ remedial responses to these ‘illegal works’ generate important social and policy issues. Granting owners of copyright in illegal works the full panoply of remedies might incentivize or normalise illegal behaviour and effectively reward wrongdoing. And yet, moderating remedies may appoint judges as moral guardians. Focusing on Anglo-Australian law, this article examines whether the unlawfulness infecting illegal works can and should be considered by courts in exercising their remedial discretion in two main contexts. First, it investigates when and why courts have refused to enforce copyright on public policy grounds, and attempts to distil relevant principles from diverse decisions. Second, the article considers the relevance of illegality when courts exercise their equitable jurisdiction, focusing on the remedy of a constructive trust which grants the benefit of copyright to the victim of the author's wrongdoing. The article argues that, in narrow circumstances, courts should have the flexibility to offset the illegality on public policy grounds and by imposing a remedial constructive trust.
Los dibujos de Aldo van Eyck para su casa en Loenen aan de Vecht: un laberinto hecho de cosas
Authors: Campos Uribe Alejandro
Published: July 2019

Aldo y Hannie van Eyck se trasladaron de Amsterdam a Loenen en 1964, reformando una antigua construcción junto al río Vecht que ha permanecido inédita hasta la actualidad. En su casa, habitada hasta 1999, Van Eyck desplegó las mismas estrategias arquitectónicas que en sus proyectos más conocidos, construyendo un interior  que refleja su modo de comprender la profesión y su manera de habitar. Este breve ensayo se fija en los dibujos elaborados por el arquitecto en el proceso de proyecto, publicados por primera vez, recomponiendo la casa como montaje de fragmentos autónomos  estudiados individualmente. Los dibujos, mezcla de bocetos y planimetrías a escala, presentan una casa hecha de cosas, un verdadero laberinto que exige la participación del que la recorre para ser comprensible. Al fin y al cabo, el dibujo no es tanto una herramienta de representación como un instrumento que facilita el pensamiento.