bluuebunny/crossref_metadata_2025 huggingface dataset:
Properties of Alkali Activated Ground Granulated Blast Furnace Slag Based Geopolymers
Authors: Severin Ilenuta , Vlad Maria
Published: February 2017

Ground granulated blast furnace slag, red mud, wheat straw ash are secondary material which after alkaline activation can be used in the construction materials’ domain. Their disposal poses a threat to the environment, whereas by reusing them we would be able to reduce this negative impact. This paper describes the research carried out in order to synthesise some geopolymer recipes, which are based on ground granulated blast furnace slag, red mud and wheat straw ash, alkaline activated with sodium hydroxide or a solution made with sodium hydroxide and sodium silicate. Factors that influence the compression strength have been studied such as: the nature of the alkaline activator, the chemical composition of solid materials in the recipes and the curing time. The geopolymer samples have been dried at room temperature for 7 and 28 days, respectively, and after the compressive strength tests has been made. Following this research it has been found out that NaOH/Na2SiO3 activated geopolymer samples have shown a higher resistance in the compressive strength. From the SEM analysis it has been found out that the samples with a higher amount of ground granulated blast furnace slag in their composition had a more homogeneous and less porous design than those with a smaller amount of ground granulated blast furnace slag.
Behavior Analysis of a Ship Structure Made out of Composite Materials
Authors: Presura Adrian , Chirica Ionel , Beznea Elena Felicia
Published: February 2017

. In this paper a parametric static and torsion analysis on a catamaran ship structure made out of composites materials is performed. The best solution for material selection is based on specific criteria for certain analysis. For dynamic analysis, the main criteria is to obtain the structure natural frequencies in a range, far from the resonance frequencies produced by the ship propulsion installation, wave loads etc. For static analysis the comparative criteria is to obtain the lowest weight of structure for the same strength. Also, buckling item is other criteria for comparative analysis. The comparative analysis is performed between rule based scantling structure and a FEM based structure for a composite material twin hull deck, in order to reduce the total hull weight. Material used for ship deck structure of the analyzed ship is e-glass polyester.
Obtaining and Characterization of Ni-Ti Alloys Processed through Powder Metallurgy
Authors: Potecaşu Florentina , Potecaşu Octavian , Braz Fernandes Francisco Manuel , Alexandru Petrică , Alexa Alexandru
Published: February 2017

This study presents the result of the researches regarding the obtaining of NiTi alloy through powder metallurgy (PM) as a possible alternative to present technologies (melting through induction in vacuum—MIV and re-melting with electric arch in vacuum—VAR). The researches made by the authors have aim at the obtaining of Ni-Ti materials with fine grain or ultrafine grain through powder metallurgy techniques, starting from ordinary metallic powders of Ti, Ni, Cu, with grain size less than 100 micrometers, and also using processing through severe plastic deformation (HPT — high pressure torsion). The fabrication through PM has an important advantage because a product requires low processing subsequent considering that it can get with sizes and shape very similar to the final ones, which is not negligible if one takes into account that the alloys Ni-Ti do not excel on cutting processability. Cylindrical samples were produced by cold uniaxial compression, at the specific pressure of 600 MPa, dosed in a proportion of 52.5 % Ni + 43.5 % Ti + 4.0 % Cu, mass composition. The compressed samples, after the sintering in vacuum and severe plastic deformation have been characterized by X-ray diffraction (XRD) , differential scanning calorimetry (DSC) and optical microscopy.
Buckling and Ultimate Strength Assessment of Ship Hull Layered Composite Panels
Authors: Lupu Bogdan Ionut , Beznea Elena Felicia , Chirica Ionel
Published: February 2017

Parametric study to evaluate the influence of the sides ratio on the axial buckling and postbuckling behaviour of the layered composite plates used in ship deck structure, is presented. In the deck structure, the plates (outlined by two pairs of longitudinal and transversal stiffeners) have obviously quadrilateral shape (from triangle to quadratic shapes). The presence of the in-plane loading, occurred from the ship hull general bending, may cause buckling of layered panels. The parametric calculus was performed for various values of ratio between the minimum and maximum value of the sides. The numerical analysis on the trapezoidal plates is presented, including the graphical results for all values of loading and side ratios.
The Selection and Characterization of the Absorptive Coatings Used to Laser Surface Treatments of Tool Steel Parts
Authors: Alexandru Petrică , Boiciuc Simona
Published: February 2017

The paper presents the experimental results on the surface quenching by CO2 continuous wave laser action of solid phase steel with 1%C obtained, using different absorptive (ZnO, TiO2, ZrO2, graphite) powder coatings. The absorptivity of these coatings was determined by resolving the thermal conductivity equation for the irradiation with an energy punctual source on the massive body. Among the four investigated powders, for thermal treatment with laser of tools carbon steel it is recommend the powder of zinc oxide as coating with most efficient absorption capacity.
Analytical Technique for Estimating the Termophysical Properties of Hybrid Nanofluids
Authors: Moldoveanu Madalina Georgiana , Simionescu Tudor Mihai , Minea Alina Adriana , Dima Adrian
Published: February 2017

Over the past years, the development of functional heat transfer fluids by compounding different substances or different phases of matter (solid, liquid, or gas) has raised increasing interest in view of their potential applications in technologies. In particular, the nanofluids in which the solid particles (<100 nm or smaller) are incorporated as the dispersed phase in the suspensions, are currently focus of great attention because of their perspective potentials as high-performance heat transfer fluids. The potential advantage of utilizing the nanofluid lies mainly in its drastic increase in the thermal conductivity. This paper presents a study of the thermophysical characteristics of some nanofluids and their hybrids. General correlations for the effective thermal conductivity and viscosity of nanofluids are used for this analysis. Regarding the importance of thermophysical properties of water based drilling fluids, the effects of insertion of two oxides in an alumina-water nanofluid on the thermal conductivity, viscosity and density of distilled water were investigated. According to the results, viscosity and density of the nanofluids increased with the concentration. At high concentrations, the least increase in the viscosity of distilled water by adding the nanomaterials is related to H2 (8.2% increase at 1.0 wt.%). As the results show, increase in the density of distilled water by adding the nanomaterials is insignificant, that in the worst case it did not exceed 0.9%. The least increase in the density of base fluid at high concentrations was for H1.
The Influence of Electrodes Deposition on the Interface and Dielectric Characteristics of Polymer Gate for Thin Films Transistors
Authors: Herbei Elena Emanuela , Jank Michael P.M. , Oertel Susanne , Frangu Laurentiu , Mușat Viorica
Published: February 2017

The paper presents some results on the effect of the metal electrode deposition on the electrical performance of amorphous polymthylmetacrylate (PMMA) thin films, measured in a MIM structure consisting of metal (Al)-insulator (PMMA)-metal (Ta). Aluminium (Al) electrode was deposited by physical vapor deposition method (PVD) on the top of PMMA film with the deposition rate of 5 and 10Å/s. The effect of aluminium deposition rate and post deposition annealing temperature on the morphology of the interface between Al electrode (100 or 300 nm thick) and PMMA thin film (40 or 70 nm thick) has been investigated by cross-section scanning electron microscopy (SEM). Based on SEM data, I-V characteristic measurements and dielectric constant values of insulating films, the deposition parameters of Al top-electrode was optimised. Our results showed that when the deposition of the Al electrode take place at a rate of 10 Å/s, no inter-diffusion or interfacial reaction at the interface between Al electrode and PMMA films were observed and the best delectric parameters of PMMA thin film were measured, which led to the best dielectric performance of PMMA layer in TFT configuration.
Effect of Severe Plastic Deformation on the Structure and Magnetic Behaviour of an Fe-Mn-Si Shape Memory Alloy
Authors: Gurau Gheorghe , Gurau Carmela , Tolea Felicia , Valeanu Mihaela , Sampath Vedamanickam , Bujoreanu Leandru Gheorghe
Published: February 2017

This work focuses on the relation between severe plastic deformation process via HSHPT and magnetic properties of an Fe–Mn–Si-Cr shape memory alloy. High speed high pressure torsion (HSHPT) was applied on cast state of alloy. Microstructure evolution of severe plastic deformed iron based alloy subjected to different deformation degree were investigated. The microstructure and phase compositions of alloy were characterized using optical microscopy, scanning electron microscopy and transmission electron microscopy. The magnetic properties are discussed on the basis of the severe plastic deformation process and the underlying martensitic transformation. Thermomagnetic curves, between 150 K and 390 K and magnetic hysteresis loops at 300 K temperatures were measured. The thermo-resistivity measurements were done by standard four-probe. The magnetic properties are interpreted and correlated with microstructure.
Microstructure and Wear Resistance of FeNiCrMnCu High Entropy Alloy
Authors: Buluc Gheorghe , Florea Iulia , Chelariu Romeu , Rusu Oana , Carcea Ioan
Published: February 2017

In this paper it is presented the microstructure and wear resistance of FeNiCrMnCu high entropy alloy. High entropy alloys are composed by at least five metallic elements in equimolar or non-equimolare proportions. High entropy alloys a brand new category of metallic materials, appeared to be a new effort in materials science and engineering, which attracted great interest. To obtain FeNiCrMnCu high entropy alloy we used an 8000 Hz induction furnace. The chemical composition was determined by EDAX. Microstructural analysis was performed using optical microscopy and SEM (scanning electron microscopy), which showed that the FeNiCrMnCu high entropy alloy has a dentritic structure and form a solid solution. Choosing copper as the main element (copper tends to segregate in interdentritic region due to its positive enthalpy of mixing with many common elements) [1], along with the iron, nickel, chromium and manganese, led to obtaining a dentritic structure specify for solid solution, which, however, did not lead to a significant hardness for FeNiCrMnCu high entropy alloy. In this work we selected pure metallic elements like: Fe, Ni, Cr, Mn and Cu. The quantity of alloy developed has 1.5 kg. Friction and wear resistance were the studied by using a reciprocating sliding test machine, in a pin on disk configuration, using aluminum as counter face. Hardness value regarding FeNiCrMnCu high entropy alloy was 184 HV and medium friction coefficient value for FeNiCrMnCu high entropy alloys was 0.86 for 28 minutesc and 1.13 for the first 20 seconds.
Wettability in Aluminium-Graphite Particles Composites (Review)
Authors: Faleh Hazim , Noori Muna , Ştefănescu Florin , Neagu Gigel , Stefan Eduard Marius
Published: February 2017

The paper presents some aspects regarding the wetting conditions in aluminium – graphite composite. The wettability depends on several factors like the presence of the oxide skin at the melt surface, formation Al4C3 at the interface between Al and particles, temperature, pressure etc. In this paper, the conditions of perfect wettability of carbon by molten Al achieved under MCl–K2TiF6 molten salts (fluxes), alloying of the melt with surface active elements, heat treatment of reinforcement material and coating of the particles with a metallic thin layer.
Distribution of five toxic heavy metals in biotic and abiotic constituents of the Negombo Lagoon, Sri Lanka
Authors: Sivanantha N. , Wijesinghe M.R. , Wijesekara R.D.
Published: February 2017

The presence of toxic metals in water has become a matter of national concern. This situation is potentially more dangerous when it occurs in lagoons and estuaries which are both highly productive and sensitive in comparison to other natural habitats. In this study, the levels of five toxic heavy metals, As, Cd, Cr, Pb and Hg, present in several abiotic and biotic constituents of the Negombo lagoon, Sri Lanka, were investigated with the objective of assessing the potential risks of accumulation. Sampling, in five locations, was conducted from December 2014 to April 2015. Water, sediment, soil, bark and leaves of the mangrove Bruguiera gymnorhiza, and fauna of selected taxa were collected and heavy metals were analyzed using ICP – OES following microwave digestion. Apart from Cr which was detected at low levels, none of the other metals were detected in the water. Nevertheless, the five heavy metals were present in relatively large amounts in one or more of the other tested constituents, indicating lagoon pollution, depicting an overall trend water < leaves < bark < snails < fish < crab < sediment < soil. Our investigation suggests that As and Cd, due to their high levels of accumulation in soil and sediment, impose the highest potential risks. Trends in accumulation suggest non-point sources for Cd, Cr and Pb. Findings reported here call for continual monitoring and for controlling discharge of contaminated effluents into productive lagoon ecosystems.
In ligte laaie se gedigte sing soos ’n feniks deur vlamme bevry van die oortollige
Authors: De Wet Karen
Published: February 2017

No abstract available.
Vehicle OBD II Compliance Test Cases
Authors:   Vehicle E E System Diagnostic Standards Committee
Published: February 2017

The main purpose of this Recommended Practice is to verify that vehicles are capable of communicating a minimum subset of information, in accordance with the diagnostic test services specified in SAE J1979: E/E Diagnostic Test Modes, or the equivalent document ISO 15031-5: Communication Between Vehicle and External Equipment for Emissions-Related Diagnostics – Part 5: Emissions-related diagnostic services.

Any software meeting these specifications will utilize the vehicle interface that is defined in SAE J2534, Recommended Practice for Pass-Thru Vehicle Programming.
LIN Network for Vehicle Applications
Authors:   Vehicle Architecture For Data Communications Standards
Published: February 2017

This document covers the requirements for SAE implementations based on LIN 2.0. Requirements stated in this document will provide a minimum standard level of performance to which all compatible ECUs and media shall be designed. This will assure full serial data communication among all connected devices regardless of supplier.

The goal of SAE J2602-1 is to improve the interoperability and interchangeability of LIN devices within a network by resolving those LIN 2.0 requirements that are ambiguous, conflicting, or optional. Moreover, SAE J2602-1 provides additional requirements that are not present in LIN 2.0 (e.g., fault tolerant operation, network topology, etc.).

This document is to be referenced by the particular vehicle OEM component technical specification that describes any given ECU in which the single wire data link controller and physical layer interface is located. Primarily, the performance of the physical layer is specified in this document. ECU environmental and other requirements, when provided in the component technical specification, shall supersede the requirements of this document.

The intended audience includes, but is not limited to, ECU suppliers, LIN controller suppliers, LIN transceiver suppliers, component release engineers and vehicle system engineers.
Tire Pressure Systems - Management (CTIS) Type For Medium and Heavy Duty Highway Vehicles
Authors:   Truck and Bus Tire Committee
Published: February 2017

This SAE recommended practice defines the system and component functions, measurement metrics, testing methodologies for evaluating the functionality and performance of ground vehicle CTIS. Systems of this type allow the driver to select the operational tire pressure set point (TPSP) based on off-highway conditions, and, upon returning to highway operations, maintain the inflation pressure to the vehicle specified level.

These systems are recommended to address all serviceable tires as originally installed on a vehicle by the OEM and/or specialty vehicle manufacturer, and, for the aftermarket (including replacement or spare parts) are recommended (but optional) to address all tire/rim combinations installed after initial vehicle sale or in-use dates.

Systems for use by military and some other very rigorous off-road applications require such extreme performance requirements, particularly at very high and low temperature and other combat-based extremes that such applications may fall outside the recommended parameters of the subject document. In those cases, it’s the responsibility of the procuring customer, vehicle OEM, and applicable component(s) OEM to determine what compromises might be required, and the suitability of design and performance solutions that may be outside of those recommended here.

This document is applicable to all axle and all wheel combinations for the following vehicle types, but does not preclude it’s use on other vehicle types - single unit powered vehicles exceeding 7257 kg (16,000_US lbs) gross vehicle weight rating (GVWR), and multi-unit vehicle combinations, up to three (3) towed units, which use an SAE J560 connector for power and/or communication, or equivalent successor connector technology. For combination vehicles including two or more trailers, the dolly axles are also included. The included vehicles can be newly manufactured vehicles or existing vehicles, fitted with air or hydraulic braking systems.

Special Note: Equipment known as ‘dual tire equalizers’ are commonly used with this category of vehicles. When installing a CTIS system, dual tire equalizers systems are not recommended as they run counter to the purpose of the management system.

NOTE: The following systems are not being addressed in this edition of the subject document.

1

Tire Pressure Monitoring Systems - these systems have been addressed under SAE J2848-1.

2

Tire Pressure Maintenance Systems - these systems have been addressed under SAE J2848-2.
Brake Rotor Thermal Cracking Procedure for Vehicles Below 4 540 kg GVWR
Authors:   Brake Dynamometer Standards Committee
Published: February 2017

This recommended practice is derived from common test sequences used within the industry. This procedure applies to all on-road passenger cars and light trucks up to 4 540 kg of GVWR. This recommended practice does not address other aspects such as performance, NVH, and durability. Test results from this recommended practice should be combined with other measurements and dynamometer tests (or vehicle-level tests), and acceptance criteria to validate a given design or configuration.
SAE Electrical Energy Storage Device Labeling Recommended Practice
Authors:   Battery Tape and Label Committee
Published: February 2017

This SAE Recommended Practice provides for labeling guidelines at all levels of component, subsystem and system level architectures describing content, placement and durability requirements of specific unit throughout the total product life cycle from inception to reclamation.
Friction Material Elastic Constants Determination through FRF Measurements and Optimization
Authors:   Brake NVH Standards Committee
Published: February 2017

This SAE Standard specifies necessary procedures and control parameters in estimating anisotropic elastic constants of friction material based on pad assembly FRF measurements and optimization. It is intended to provide a set of elastic constants as inputs to brake NVH simulation, with the objective of ensuring pad assembly vibration correlation between simulation and measurements.
Devising a Sketch Grammar for Academic Portuguese
Authors: Zingano Kuhn Tanara , Kosem Iztok
Published: February 2017

This paper presents the development of a new sketch grammar designed specifically for CoPEP, a newly compiled 40-million corpus comprising texts from academic journals, tagged with Freeling v3, the default tagger available in the Sketch Engine for corpora of Portuguese. We first provide an overview and evaluation of existing sketch grammars for Portuguese, followed by a detailed description of the development of a new sketch grammar, and the presentation of some of the problems encountered. We conclude by summarizing the main findings, highlighting important implications, and offering suggestions for further improvement of the sketch grammar. More accurate and varied word sketch results than those offered by the current default sketch grammar indicate that our sketch grammar can be used for advanced lexicographic tasks such as automatic extraction of lexical data from CoPEP, the methodology of knowledge acquisition planned for the compilation of the proposed dictionary of Portuguese for university students. Moreover, this new sketch grammar can be used with any other corpus of Portuguese tagged with Freeling v3, which makes it an important resource for lexicographic and corpus linguistic research of the Portuguese language.
Aerosol vertical distribution and optical properties over China from long-term satellite and ground-based remote sensing
Authors: Tian Pengfei , Cao Xianjie , Zhang Lei , Sun Naixiu , Sun Lu , Logan Timothy , Shi Jinsen , Wang Yuan , Ji Yuemeng , Lin Yun , Huang Zhongwei , Zhou Tian , Shi Yingying , Zhang Renyi
Published: February 2017

Abstract. The seasonal and spatial variations of vertical distribution and optical properties of aerosols over China are studied using long-term satellite observations from the Cloud–Aerosol Lidar with Orthogonal Polarization (CALIOP) and ground-based lidar observations and Aerosol Robotic Network (AERONET) data. The CALIOP products are validated using the ground-based lidar measurements at the Semi-Arid Climate and Environment Observatory of Lanzhou University (SACOL). The Taklamakan Desert and Tibetan Plateau regions exhibit the highest depolarization and color ratios because of the natural dust origin, whereas the North China Plain, Sichuan Basin and Yangtze River Delta show the lowest depolarization and color ratios because of aerosols from secondary formation of the anthropogenic origin. Certain regions, such as the North China Plain in spring and the Loess Plateau in winter, show intermediate depolarization and color ratios because of mixed dust and anthropogenic aerosols. In the Pearl River Delta region, the depolarization and color ratios are similar to but higher than those of the other polluted regions because of combined anthropogenic and marine aerosols. Long-range transport of dust in the middle and upper troposphere in spring is well captured by the CALIOP observations. The seasonal variations in the aerosol vertical distributions reveal efficient transport of aerosols from the atmospheric boundary layer to the free troposphere because of summertime convective mixing. The aerosol extinction lapse rates in autumn and winter are more positive than those in spring and summer, indicating trapped aerosols within the boundary layer because of stabler meteorological conditions. More than 80 % of the column aerosols are distributed within 1.5 km above the ground in winter, when the aerosol extinction lapse rate exhibits a maximum seasonal average in all study regions except for the Tibetan Plateau. The aerosol extinction lapse rates in the polluted regions are higher than those of the less polluted regions, indicating a stabilized atmosphere due to absorptive aerosols in the polluted regions. Our results reveal that the satellite and ground-based remote-sensing measurements provide the key information on the long-term seasonal and spatial variations in the aerosol vertical distribution and optical properties, regional aerosol types, long-range transport and atmospheric stability, which can be utilized to more precisely assess the direct and indirect aerosol effects on weather and climate.
Technical note: Simultaneous fully dynamic characterization of multiple input–output relationships in climate models
Authors: Kravitz Ben , MacMartin Douglas G. , Rasch Philip J. , Wang Hailong
Published: February 2017

Abstract. We introduce system identification techniques to climate science wherein multiple dynamic input–output relationships can be simultaneously characterized in a single simulation. This method, involving multiple small perturbations (in space and time) of an input field while monitoring output fields to quantify responses, allows for identification of different timescales of climate response to forcing without substantially pushing the climate far away from a steady state. We use this technique to determine the steady-state responses of low cloud fraction and latent heat flux to heating perturbations over 22 regions spanning Earth's oceans. We show that the response characteristics are similar to those of step-change simulations, but in this new method the responses for 22 regions can be characterized simultaneously. Furthermore, we can estimate the timescale over which the steady-state response emerges. The proposed methodology could be useful for a wide variety of purposes in climate science, including characterization of teleconnections and uncertainty quantification to identify the effects of climate model tuning parameters.
Depolarization Ratios Retrieved by AERONET Sun/Sky Radiometer Data and Comparison to Depolarization Ratios Measured With Lidar
Authors: Noh Youngmin , Müller Detlef , Lee Kyunghwa , Kim Kwanchul , Lee Kwonho
Published: February 2017

Abstract. The linear particle depolarization ratios at 440, 675, 870, and 1020 nm were derived using data taken with AERONET sun/sky radiometer at Seoul (37.45° N, 126.95° E), Kongju (36.47° N, 127.14° E), Gosan (33.29° N, 126.16° E), and Osaka (34.65° N, 135.59° E). The results are compared to the linear particle depolarization ratio measured by lidar at 532 nm. The correlation coefficient R2 between the linear particle depolarization ratio derived by AERONET data at 1020 nm and the linear particle depolarization ratio measured with lidar at 532 nm is 0.90, 0.92, 0.79, and 0.89 at Seoul, Kongju, Gosan, and Osaka, respectively. A good correlation between the lidar-measured depolarization ratio at 532 nm and the one retrieved by AERONET at 870 nm. We find correlation coefficients R2 of 0.89, 0.92, 0.76, and 0.88 at Seoul, Kongju, Gosan, and Osaka, respectively. The correlation coefficient for the data at 675 nm is lower than the correlation coefficient at 870 and 1020 nm. We find correlation values of 0.81, 0.90, 0.64, and 0.81 at Seoul, Kongju, Gosan, and Osaka, respectively. The lowest correlation values are found for the AERONET-derived linear particle depolarization ratio at 440 nm. We find values of 0.38, 0.62, 0.26, and 0.28 at Seoul, Kongju, Gosan, and Osaka, respectively. The linear particle depolarization ratio can be used as a parameter to obtain insight into the variation of optical and microphysical properties of dust when it mixed with anthropogenic pollution particles. The single-scattering albedo decreases with increasing measurement wavelength for low linear particle depolarization ratios. In contrast, single-scattering albedo increases with decreasing wavelength for high linear particle depolarization ratios. The retrieved volume particle size distributions are dominated by the fine-mode fraction if linear particle depolarization ratios are less than 0.15 at 532 nm. The fine-mode fraction of the size distributions decreases and the coarse-mode fraction of the size distribution increases for increasing the linear particle depolarization ratio at 1020 nm. The dust ratio based on using the linear particle depolarization ratio derived from AERONET data is 0.12 to 0.17 lower than the coarse-mode fraction derived from the volume concentrations of particle size distributions in which case we can compute the coarse-mode fractions of dust.
A new device to mount portable energy-dispersive X-ray fluorescence spectrometers (p-ED-XRF) for semi-continuous analyses of split (sediment) cores and solid samples
Authors: Hoelzmann Philipp , Klein Torsten , Kutz Frank , Schütt Brigitta
Published: February 2017

Abstract. Portable energy-dispersive X-ray fluorescence spectrometers (p-ED-XRF) have become increasingly popular in sedimentary laboratories to quantify the chemical composition of a range of materials such as sediments, soils, solid samples, and artefacts. Here, we introduce a low-cost, clearly arranged unit that functions as a sample chamber (German industrial property rights no. 20 2014 106 048.0) for p-ED-XRF devices to facilitate economic, non-destructive, fast, and semi-continuous analysis of (sediment) cores or other solid samples. The spatial resolution of the measurements is limited to the specifications of the applied p-ED-XRF device – in our case a Thermo Scientific Niton XL3t p-ED-XRF spectrometer with a maximum spatial resolution of 0.3 cm and equipped with a charge-coupled device (CCD) camera to document the measurement spot. We demonstrate the strength of combining p-ED-XRF analyses with this new sample chamber to identify Holocene facies changes (e.g. marine vs. terrestrial sedimentary facies) using a sediment core from an estuarine environment in the context of a geoarchaeological investigation at the Atlantic coast of southern Spain.
Detection systems for antibody responses against herpes B virus
Authors: Pöhlmann Stefan , Krüger Astrid , Hafezi Wali , Schneider Stefan , Gruber Jens , Winkler Michael , Kaul Artur
Published: February 2017

Abstract. Herpes B virus (BV) infection is highly prevalent among adult Asian macaques and rarely causes severe disease in infected animals. In contrast, BV infection of humans can induce fatal encephalitis in the absence of treatment. Therefore, the development of diagnostic tests for specific and sensitive detection of antibodies against BV is an important task. The cross-reactivity of antibodies against BV with related simplex viruses of other primates may afford an opportunity to obtain sensitive detection systems without the need to work with the highly pathogenic BV. Moreover, it has been proposed that use of recombinant viral glycoproteins may allow for a detection of antibody responses against BV with high specificity. However, limited data are available for both approaches to BV diagnostic. Here, we report that simian agent 8 (SA8; infects African green monkeys)- and herpesvirus papio 2 (HVP-2; infects baboons)-infected cells allow for a more sensitive detection of antibody responses against BV in macaques than lysates of herpes simplex virus type 1 and 2 (HSV-1/2; infect humans)-infected cells and a commercial HSV ELISA (Enzygnost® Anti-HSV/IgG). In addition, we show that sera from BV-infected macaques frequently contain antibodies against the recombinant BV glycoprotein gD (BV gD) that has been previously proposed as a diagnostic target for discriminating BV- and HSV-induced antibodies. However, we found that antibodies of some HSV-infected human patients also reacted with BV gD. In contrast, only sera of HSV-1- and HSV-2-infected humans, but not sera from BV-infected macaques, reacted with HSV-1/2 gG. Collectively, these results suggest that both SA8 and HVP-2 allow for sensitive and comparable detection of BV-directed antibody responses in macaques and that the combination of BV gD and HSV-1/2 gG needs to be complemented by a least one additional viral glycoprotein for reliable discrimination between antibody responses against BV and HSV-1/2 in humans.
Brief Communication: On the influence of vertical velocity profiles on the combined power output of two model wind turbines in yaw
Authors: Schottler Jannik , Hölling Agnieszka , Peinke Joachim , Hölling Michael
Published: February 2017

Abstract. The effect of vertical velocity gradients on the total power output of two aligned model wind turbines as a function of yaw misalignment of the upstream turbine is studied experimentally. It is shown that asymmetries of the power output of the downstream turbine and the combined power of both with respect to the upstream turbine's yaw misalignment angle can be linked to the vertical velocity gradient of the inflow.
Normal Values for Microperimetry with the MAIA Microperimeter: Sensitivity and Fixation Analysis in Healthy Adults and Children
Authors: Molina-Martín Ainhoa , Piñero David P. , Pérez-Cambrodí Rafael J.
Published: February 2017

Purpose

To establish normative values of retinal sensitivity and parameters describing the fixation pattern using macular analyzer integrity assessment (MAIA) microperimetry (Centervue, Padova, Italy) in adults and children.

Methods

A sample of 237 eyes of 237 healthy subjects aged between 10 and 70 years (mean age 30.63 ± 16.23 years) was evaluated using the MAIA microperimeter. The following parameters provided by the MAIA device were evaluated: average threshold (AT), macular integrity, fixation indexes (P1% and P2%), bivariate contour ellipse area (BCEA) for 95% and 63% of points, and horizontal (H) and vertical (V) axes of the ellipse of fixation. Differences between different age-related groups were evaluated. Correlation of microperimetric parameters with age was also assessed.

Results

Median retinal sensitivity of the overall sample was 32.90 dB (interquartile range 1.80 dB). Median P1 and P2 values were 98.00% (6.00) and 100.00% (1.00), respectively. Median BCEA for 95% and 63% of points were 2.40°2 (4.50) and 0.30°2 (0.50), respectively. Median H and V were 0.90° (0.80) and 0.90° (0.70), respectively. Age was significantly correlated with the following parameters in subjects from 21 to 70 years of age (p<0.01): AT (rho -0.47), P1 (rho -0.37), BCEA95 (rho 0.43), BCEA63 (rho 0.42), H (rho 0.43), and V (rho 0.40).

Conclusions

Retinal sensitivity in healthy eyes tends to decrease with age as well as the stability of the pattern of fixation. A normative database in terms of retinal sensitivity threshold and fixation performance can be established in this type of eyes.
The Evaluation of Central Corneal Thickness and Intraocular Pressure in Conjunction with Tear IGF-1 Levels in Patients with Acromegaly
Authors: Kan Emrah , Kan Elif K. , Okuyucu Ali
Published: February 2017

Purpose

To compare the central corneal thickness (CCT), intraocular pressure (IOP), and tear insulin-like growth factor 1 (IGF-1) levels between patients with acromegaly and a control group and to evaluate the possible effect of tear IGF-1 and duration of the disease on CCT and IOP.

Methods

We included 31 patients with acromegaly (study group) and 40 age- and sex-matched controls in the study. Patients with acromegaly were divided into 2 subgroups based on disease status (active/inactive). All participants underwent complete ophthalmologic evaluation including CCT and IOP values. Basal tear samples were collected from both groups and tear IGF-1 levels were measured. The CCT, IOP, and tear IGF-1 levels were compared between groups and subgroups and the association between tear IGF-I levels and ocular parameters (CCT, IOP) and disease duration were also evaluated.

Results

Central corneal thickness, IOP, and tear IGF-1 levels did not show a significant difference between study and control groups. We also did not find a significant difference in terms of CCT, IOP, or tear IGF-1 levels between subgroups of patients. Correlation analysis did not show an association between the duration of disease and tear IGF-1 levels with CCT or IOP.

Conclusions

There was no significant difference in tear IGF-1 levels between patients with acromegaly and controls. Additionally, there was no correlation between disease duration and tear IGF-1 levels with CCT or IOP levels. This lack of association may suggest that tear IGF-1 levels might not have an effect on CCT or IOP findings in patients with acromegaly.
Effect of Intravitreal Aflibercept on Central Retinal Arterial Blood Flow in Type 1 Retinopathy of Prematurity
Authors: Sukgen Emine A. , Söker Gökhan , Koçluk Yusuf , Gülek Bozkurt
Published: February 2017

Purpose

To evaluate the blood flow changes of the central retinal artery measured with color Doppler imaging (CDI) in infants receiving intravitreal aflibercept (IVA) for treatment of type 1 retinopathy of prematurity (ROP).

Methods

Patients with type 1 ROP were assessed prospectively by CDI following IVA. Color Doppler imaging was used to measure the peak systolic velocity, end diastolic velocity (EDV), pulsatility index (PI), and resistivity index (RI) of the central retinal artery (CRA) before IVA injection and 1 hour, 1 week, and 1 month after injection.

Results

A total of 29 eyes of 15 infants were included in this study. The mean gestational age at birth was 28.62 ± 2.48 weeks and the mean birthweight was 1,198.62 ± 348.99 g. All treated eyes showed complete regression of ROP and peripheral retinal vascularization continued. Measurements of EDV-CRA, RI-CRA, and PI-CRA showed significant changes after IVA treatment.

Conclusions

This study showed that IVA is an effective treatment for type 1 ROP. After IVA treatment, vascular resistance increases, ocular blood flow decreases, and changes in hemodynamic parameters of CRA may remain for a month. Further studies are needed to evaluate the effect of anti-vascular endothelial growth factor agents on ocular hemodynamics in infants with ROP.
Intravitreal Dexamethasone Implant (Ozurdex®) for Exudative Retinal Detachment after Proton Beam Therapy for Choroidal Melanoma
Authors: Malclès Ariane , Nguyen Anh-Minh , Mathis Thibaud , Grange Jean-Daniel , Kodjikian Laurent
Published: February 2017

Purpose

To evaluate the efficacy and safety of intravitreal 0.7-mg dexamethasone implant (DEX-I) (Ozurdex®) in the treatment of extensive exudative retinal detachment (RD) associated with uveal melanoma treated using proton beam therapy (PBT).

Methods

Data from 10 patients with exudative RD after PBT treated with intravitreal injection of 0.7-mg DEX-I were reviewed retrospectively. The main outcome measures were resolution of exudative RD, visual acuity, and safety profile.

Results

Mean age was 55.6 years (range 34-85). Mean time between PBT and DEX-I was 12.4 months (range 3-25). Mean follow-up was 9.9 months (range 4-15). Intravitreal Ozurdex® reduced exudative RD in 7 cases (70%) on average 3.1 months after injection with complete resolution of RD in 6 of these (60%). For half of the patients, their level of vision remained stable; the other half experienced a deterioration in visual acuity at the end of follow-up. No adverse effects were observed.

Conclusions

In this small case series, treatment with intravitreal DEX-I reduced exudative RD in the majority of cases and had an acceptable safety profile.
Inverted Femoral Head Graft versus Standard Core Decompression in Nontraumatic Hip Osteonecrosis at Minimum 3 Years Follow-up
Authors: Sallam Asser A. , Imam Mohamed A. , Salama Khaled S. , Mohamed Osman A.
Published: February 2017

Purpose

Numerous salvage surgeries were popularised to halt the progression of hip osteonecrosis (ON). We aimed to compare the clinico-radiological outcomes of inverted femoral head graft (IFHG) versus standard core decompression (SCD) in treatment of nontraumatic hip ON at pre-arthritic stage.

Methods

A case review was performed at a minimum 3 years follow-up of 61 patients (71 hips; mean age 32.96 (19-50) years; mean follow-up 7.86 (3-14) years; mean body mass index 28.58 (19-46); 32 males, 29 females) suffering nontraumatic hip ON at pre-arthritic stage. 38 hips underwent SCD and 33 IFHG. The outcome was assessed by changes in modified Harris Hip Score (MHHS), need for revision surgery and progression of modified Ficat-Arlet staging. Data were analysed including logistic regression and Kaplan-Meier survivorship analysis.

Results

13/34 (38.2%) hips in SCD group were revised at 4.61 ± 2.61 years, while 7/33 (21.2%) in IFHG group at 8.43 ± 4.32 years (p = 0.023). MHHS was significantly higher in IFHG group at 1 and 3 years as well as at last follow-up (p = 0.014, 0.001 and 0.023 respectively). Clinical and radiological significant differences were found in survivorship analysis between both groups, in favor of IFHG. A higher clinical failure was noted among obese patients.

Conclusions

An IFHG technique offers a better alternative regarding postoperative clinico-radiological outcomes in nontraumatic hip ON at the pre-arthritic stage. A cautious prognosis is recommended in obese patients.
Usefulness of Measuring Acetabular Anterior Coverage Using a Tomosynthesis Imaging System
Authors: Ohtsuru Tadahiko , Morita Yasuyuki , Horiuchi Yuhei , Murata Yasuaki , Shimamoto Shuji , Morita Yuji , Munakata Yutaro , Kato Yoshiharu
Published: February 2017

Purpose

The purpose of this study was to compare the usefulness of measuring acetabular anterior coverage by tomosynthesis and false profile (FP) radiography.

Methods

70 hips in 35 patients who were diagnosed with early stage osteoarthritis of the hip, and 60 hips from 30 healthy volunteers were analysed. Plain FP radiographs were taken, and vertical-centre-anterior margin (FP-VCA) angles were measured. Acetabular anterior coverage was measured in the natural standing position using a tomosynthesis imaging system in the sagittal plane. As with FP radiography, we measured vertical-centre-anterior margin (TS-VCA) angles.

Results

The median values of the FP-VCA angle, and TS-VCA angle were 43.8°, 54.4°, respectively. The TS-VCA angle was significantly larger than the FP-VCA angle. For FP radiographs, the intraobserver intraclass correlation coefficient (ICC) was 0.68, and the interobserver ICC was 0.79. For tomosynthesis sagittal images, the intraobserver ICC was 0.85, and the interobserver ICC was 0.92. There was a strong positive correlation between the TS-VCA angle and the FP-VCA angle. When the FP-VCA angle was 25°, the TS-VCA angle was 35° in regression analysis.

Conclusions

Measuring acetabular anterior coverage using sagittal plane tomosynthesis correlates well with FP radiography. Regardless of the presence of acetabular deformities, tomosynthesis demonstrated high reproducibility, simple posture setting, low effective doses, and high versatility. A cut-off value of 35° was useful for the detection of developmental dysplasia of the hip joint using the TS-VCA angle.
Stable Migration Pattern of an Ultra-Short Anatomical Uncemented Hip Stem: A Prospective Study with 2 Years Radiostereometric Analysis Follow-Up
Authors: Mahmoud Ahmed Nageeb , Kesteris Uldis , Flivik Gunnar
Published: February 2017

Introduction

Shorter, anatomically shaped and proximally loading stems have been developed to achieve better stress distribution and be more bone preserving. The purpose of this prospective study was to evaluate the migration pattern of the Proxima™ ultra-short uncemented stem using radiostereometric analysis (RSA), and to review the literature regarding the migration of short stemmed hip arthroplasty.

Methods

25 patients (28 hips) with hip osteoarthritis received a Proxima stem during total hip arthroplasty (THA). To measure stem migration, repeated RSA examinations were done during a 2 year follow up period. The patients were evaluated with the hip specific (HOOS) and the generic health (EQ5D) scores up to 1 year, and clinically for 6 years postoperatively.

Results

Almost all migration occurred within the first 3 months, with mean subsidence of 0.22 mm and varus rotation of 1.04°, being the primary effect variables. After the third postoperative month and up to the 2 year RSA follow up no further significant migration occurred. The outcome scores showed substantial improvement after 1 year. No revisions were performed or indicated for any stem after a mean clinical follow up of 72.1 months.

Conclusions

Like many other uncemented stems, the Proxima showed early migration up to 3 months hereafter osseointegration seems to have occurred. The achieved stability and clinical outcomes indicate favorable early results for this stem in younger patients who have good bone quality and average BMI. We found, however, the surgical technique to be slightly more demanding compared to conventional stems owing to the unique implant design that necessitates specific adjusted femoral cutting and broaching procedures.
Screws Are Not Needed when Secure Interference Fit of Uncemented Acetabular Components is Adequate: A 5- to 15-Year Follow-up with Clinical and Radiological Analysis
Authors: García-Rey Eduardo
Published: February 2017

Purpose

Even with good surgical preparation, adequate primary stability of the acetabular component is not always achieved after primary total hip replacement (THR). We hypothesise that adequate bone preparation for appropriate cortical loading would allow us to avoid screw use.

Methods

A total of 791 uncemented cups were analysed to compare the need for screws to obtain primary fixation in 5 different designs. Arthritic hips with inflammatory arthritis or severe congenital hip disease were excluded. A press-fit technique was first tried in all hips and screws were only used when strictly needed. Radiological acetabular shape and postoperative cup position were assessed in all hips. The mean follow-up was 9.6 ( 5 – 15 ) years.

Results

Screws were required in 155 hips (19.6%). We could not detect any difference in the percentage of screw use between designs. We found that female patients (odds ratio [OR] 2.06; 95% confidence interval [CI], 1.41-3.02) and cups with a greater distance to the hip rotation centre on the postoperative radiograph (OR 1.69; 95% CI, 1.17-2.45) had a higher risk for screw use. A greater anteversion of the cup had a lower risk for screw use (OR 0.96; 95% CI, 0.94-0.99). At latest follow-up no hips had needed revision for aseptic loosening.

Conclusions

Good intraoperative technique is not enough to avoid screw use since more accurate cup position and reconstruction of the hip rotation centre are required for an adequate interference fit. A press-fit technique can provide similar mid-term results to screw use in hips without severe deformities.