bluuebunny/crossref_metadata_2025_split huggingface dataset:
Topology optimisation of an aircraft nose-wheel fork for production in Ti6Al4V by the Aeroswift high-speed laser powder bed fusion machine
Authors: Monaheng L F , du Preez W B , Kotze N , Vermeulen M 
Published: October 2020

Recent levels of structural integrity of components built in the Aeroswift high-speed laser powder bed fusion machine have led to the decision to produce a structural aircraft component through this technology. The Aeroswift machine is capable of building larger Ti6Al4V parts at a more rapid pace than current commercial laser metal powder bed fusion systems. As prototype component, the nose-wheel fork of the AHRLAC aircraft, which was conventionally machined in aluminum alloy 7050, was selected. This paper describes the design, topology optimisation and the manufacturing approach taken in this project.
Given the design space, loads, strength requirements and boundary conditions prescribed by the AHRLAC engineers, topology optimisation was performed on the nose-wheel fork to design a lightweight component for production in Ti6Al4V. Different topology optimisation software suites were used, to establish their capabilities and fit-for-purpose features. The optimised design and percentage of weight saving are presented. An assessment based on the experience with the different software suites is offered.
Microstructure and Properties of 3D Ti-6Al-4V Articles Produced with Advanced Co-axial Electron Beam & Wire Additive Manufacturing Technology
Authors: Kovalchuk Dmytro , Ivasishin Orest , Savvakin Dmytro 
Published: October 2020

Ti-6Al-4V articles were produced with advanced additive manufacturing technology of Direct Energy Deposition (DED) type using profile electron beam and wire as feedstock material. The key distinctive feature of this additive manufacturing process is the applying of the hollow conical electron beam generated by low-voltage (<20kV) gas-discharge EB gun for heating and melting of the substrate and co-axially fed wire. Such configuration ensures precisely controllable liquid metal transfer from the wire end to the substrate, specific temperature gradients at the fusion area and heat flow from liquid metal pool. Such conditions of heating, melting and cooling during 3D manufacturing processing provide the ability for controllable microstructure formation, including grain size and material texture.
Influence of processing parameters and cooling conditions on crystallization, grain formation and intragrain structure of solidified material is discussed. Optimization of processing parameters allowed production of 3D Ti-6Al- 4V articles with isotropic microstructure and mechanical properties which met standard requirements for Ti-6Al-4V alloy.
Tensile properties of α-titanium alloys at elevated temperatures
Authors: Nawaya Tarik , Beck Werner , von Hehl Axel 
Published: October 2020

Hot-deep drawing is an innovative processing technology to produce complex shaped sheet metal components with constant wall thickness from high-strength lightweight materials. For some aerospace and automotive applications oxidation resistance at medium to high temperatures is an important aspect. In terms of this titanium α-alloys are often used due to their balanced relation of strength and oxidation resistance. In the presented study the stress-strain characteristics of several α-titanium alloys were determined at ambient and elevated temperatures by means of hot tensile tests. Besides the commercially pure Titanium alloy ASTM-Grade 4, two novel α-titanium alloys were investigated. Regarding the hot forming properties a comparison with α-β Ti-6Al-4V alloy was conducted. The hot tensile tests were carried out by means of a particular forming dilatometer type “Gleeble 3500” at 400, 500, 600, 650, 700 and 800 °C. The test showed favorable peak plasticity for all α-alloys at the temperature range between 600 and 650 °C in contrast to lower or higher temperatures. All samples were metallographically characterized.Key words: titanium α-alloys, hot tensile properties, elevated temperatures, Gleeble 3500.
Corrosion of titanium alloys in pressurized water at 300 °C and 15 MPa
Authors: Quentin BIGNON , Quentin AUZOUX , Frantz MARTIN , Amandine RAYNAL , Frédéric MISERQUE , Michel TABARANT , Laurence LATU-ROMAIN , Yves WOUTERS 
Published: October 2020

Commercially pure titanium (Ti CP) and two titanium alloys (Ti 64 and Ti10-2-3) representative of different metallurgical classes were exposed to pressurized water at 300 °C, 15 MPa in a dedicated stainless steel corrosion loop up to 1632 h.
Mass uptake measurements as well as extensive characterization of the oxides formed on the polished samples using scanning and transmission electron microscopy, Raman spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, photoelectrochemistry and glow discharge optical emission spectroscopy led to the following main conclusions:
• The oxide scale was made of a thin and continuous TiO2 layer topped by small TiO2 anatase crystallites and large FeTiO3 ilmenite crystallites.
• The interface tortuosity increased with exposure duration, as well as the amount of crystallites. From 217 h exposure, the thickness of the thin continuous TiO2 layer remained constant with exposure duration.
• The mass uptake increased approximately linearly with exposure duration.
These observations were consistent with a corrosion mechanism involving simultaneous oxide growth, dissolution and precipitation. The corrosion rate of the three studied materials was estimated to be around 3 µm/year.
Effect of Melting Interruption on Composition and Microstructure of BT22 Ingot in VAR
Authors: Hua Zhengli , Luo Wenzhong , He Tao , Lei Qiang , Wang Longzhou , Liu Xianghong 
Published: October 2020

BT22 ingot was remelted by vacuum arc remelting (VAR) furnace with a melting rate of 20kg/min. The power of VA R was interrupted for five minutes when the weight of the remelted ingot is approximately 4000 kg. The melting process was then resumed at the same melting rate after the five minutes interruption. Optical microscopy (OM), inductively coupled plasma-mass spectrometry (ICP-MS) and electron probe micro analyzer (EPMA) were utilized to analyze the microstructure, composition and distribution of elements. No significant microstructural difference was oberved at the remelting interrupted region. The variation of Al, Mo, V, Cr, Fe contents between the melting interruption region and normal region is within 0.23 wt%. The distribution of elements in equiaxed grains of the melting interruption region and the normal regions were compared by EPMA analysis. The contents of Al, V, Fe and Cr increase from the center of equiaxed grains to their grain boundaries. The content of Mo decreases from the center of equiaxed grains to their grain boundaries. The trend of element content in the normal region is similar to that of the melting interrupted region.
Key words: BT22; ingot; composition; microstructure
Ti and TiAl melting with a semi-industrial PAMCHR
Authors: Ruby-Meyer Fabienne , Doridot Emiliane , Delfosse Jérôme , Hans Stéphane 
Published: October 2020

Upscaling from laboratory trials to industrialization is a critical step in the development of new metallurgical processes and products. Pilot trials are an important way to provide data that can be used to better understand and model the industrial-scale process.MetaFensch has invested in a semi-industrial Plasma Arc Melter Cold Hearth Refiner (PAMCHR) in order to support the development of the recycling of titanium scraps into aeronautical grade titanium alloy ingots.This pilot supports the industrial scale PAMCHR of the company Ecotitanium in the frame of a collaborative project with Aubert & Duval and Safran as industrial partners.The work done on the pilot scale PAMCHR consists in studying the influence of various parameters like the type of melting feedstock, plasma arc parameters, operating pressure on the final quality of the cast ingot. The goal is to understand the physico-chemical mechanisms involved in the plasma arc interacting with the liquid metal in order to optimize the melting and refining parameters for the industrial scale furnace Ecotitanium (Ti64 alloy).Ti64 and TiAl ingots were cast in 150 mm and 100 mm diameter. Chemical composition and solidification structure were characterized. The effect of the different process parameters on the titanium melt and on the ingot quality are studied. Examples of exploitation of the thermograms obtained with the thermal camera situated above the refining cold hearth will also be presented in this paper.
Quantitative relationship between microstructural factors and fatigue life of Ti-5Al-2Sn-2Zr-4Cr-4 Mo (Ti-17) fabricated using a 1500-ton forging simulator
Authors: Niinomi M. , Akahori T. , Nakai M. , Koizumi Y. , Chiba A. , Nakano T. , Kakeshita T. , Yamabe-Mitarai Y. , Kuroda S. , Motohashi N. , Itsumi Y. , Choda T. 
Published: October 2020

The microstructures, tensile properties, and fatigue lives of the forged Ti-17 using a 1500-ton forging simulator subjected to different solution treatments and a common aging treatment under both load- and strain-controlled conditions to evaluate high cycle fatigue and low cycle fatigue lives, respectively were examined. Then, the tensile properties, microstructures, and relationships between fatigue lives and the microstructural factors were discussed.
The fatigue limit under load-controlled conditions increases with increasing solution treatment temperature up to 1143 K, which is in the (α + β) region. However, it decreases with further increase in the solution treatment temperature to 1203 K in the b region. The fatigue ratio at fatigue limit is increasing with decreasing solution treatment temperature, namely increasing the volume fraction of the primary α phase, and it relates well qualitatively with the volume fraction of the primary α phase when the solution treatment temperature is less than the b transus temperature. The fatigue life under strain-controlled conditions to evaluate the low cycle fatigue life increases with decreasing solution treatment temperature, namely increasing the volume fraction of the primary α phase. The fatigue life under strain-controlled conditions to evaluate the low cycle fatigue life relates well quantitatively with the tensile true strain at breaking of the specimen and the volume fraction of the primary α phase for each total strain range.
Infektionen unter Immunsuppression nach Nierentransplantation
Authors: Kemmner Stephan , Schönermarck Ulf 
Published: October 2020

ZUSAMMENFASSUNGUnter immunsuppressiver Therapie besteht ein deutlich erhöhtes Infektionsrisiko nach Nierentransplantation (NTx), insbesondere für virale Infektionen. Bereits vor einer geplanten NTx sollte auf einen aktuellen Impfstatus geachtet werden, da nach einer Transplantation unter immunsuppressiver Therapie einerseits Lebendimpfstoffe nicht mehr gegeben werden dürfen und andererseits eine adäquate Impfantwort schwieriger zu erreichen ist. Die saisonale Influenzaimpfung kann bereits einen Monat nach Transplantation gegeben werden, für alle anderen Impfungen wird ein Abwarten von 3–6 Monaten empfohlen. Eine prophylaktische Therapie kann das Auftreten bestimmter Infektionen effektiv verhindern. Nach NTx sollte für die ersten 6 Monate eine PjP-Prophylaxe (PjP: Pneumocystis-jirovecii-Pneumonie) mit Trimethoprim/Sulfamethoxazol verabreicht werden. Eine CMV-Prophylaxe (CMV: Zytomegalievirus) mit Valganciclovir erfolgt in Abhängigkeit vom Sero-Status von Empfänger und Spender i. d. R. für 3 bzw. 6 Monate. Im Falle einer Infektion kann in Abhängigkeit vom Schweregrad der Antimetabolit (meist MMF: Mycophenolatmofetil) dosishalbiert oder pausiert werden, jedoch ist dies mit einem erhöhten Rejektionsrisiko verbunden. Insbesondere bei Infektionen mit CMV und BKV (Polyomavirus BK) kann anstelle von MMF ein mTOR-Inhibitor (mTOR: „mechanistic target of rapamycin“) eingesetzt werden in Kombination mit einem niedrigdosierten Calcineurininhibitor (CNI). Bei einer COVID-19-Erkrankung (COVID-19: Coronavirus Disease 2019) nach NTx sollte wie bei anderen Infektionen in einer Kombinationstherapie zunächst der Antimetabolit bzw. der mTOR-Inhibitor dosisreduziert oder pausiert werden. Ein Absetzen des CNIs bei COVID-19 erscheint aus unserer Sicht nicht regelhaft indiziert, sondern bleibt schweren Verläufen im Einzelfall vorbehalten. Im Falle einer antiviralen Therapie bei COVID-19 muss immer an mögliche Interaktionen mit den Immunsuppressiva (v. a. mit CNI und mTOR-Inhibitoren) gedacht werden.
Patient Reported Outcomes (PROs) – a Tool for Strengthening
Patient Involvement and Measuring Outcome in Orthopaedic Outpatient
Rehabilitation
Authors: Müller Marcus , Brunssen Joscha , Messingschlager Martin 
Published: October 2020

AbstractThe present study serves to establish Patient Reported Outcomes (PROs) as a tool
for strengthening patient involvement and measuring outcomes in orthopaedic
outpatient rehabilitation. Assessments by FFbH-R (Hannover Back Function
Questionnaire for patients with back problems), Quick-DASH (Disabilities of Arm,
Shoulder, and Hand Score for patients with upper extremity lesions), and LEFS
(Lower Extremity Function Scale for patients with lower extremity lesions) were
employed in 20 outpatient rehabilitation centres over a period of 12 months to
evaluate changes in performance and participation from the subjective patient
perspective. The following questionnaires were used: FFbH-R status post: lumbar
disc surgery; cervical disc surgery; spinal canal decompression; conservative
back pain treatment; other; Quick-DASH status post: rotator cuff reconstruction;
shoulder arthroplasty; fracture (conservative or osteosynthesis); other; LEFS
status post: hip arthroplasty; knee arthroplasty; anterior cruciate ligament
repair; osteotomy; fracture (conservative treatment or osteosynthesis); other.
Analysis of the 6,751 usable data sets demonstrated significant positive changes
in all scores and diagnostic subgroups. The mean difference in score was 14.2
points in the FFbH-R, − 22 points in the Quick-DASH and 18 points in the LEFS.
Thus, this study proves the positive effects of orthopaedic rehabilitation in an
outpatient setting. PROs were instituted on a permanent basis in seven of the
participating institutions.
Robotic-Assisted Lobectomy Favors Early Lung Recovery versus Limited Thoracotomy
Authors: Lacroix Valérie , Kahn David , Matte Pascal , Pieters Thierry , Noirhomme Philippe , Poncelet Alain , Steyaert Arnaud 
Published: October 2020

Abstract
Background Postoperative pulmonary recovery after lobectomy has showed early benefits for the video-assisted thoracoscopic surgery and sparing open techniques over nonsparing techniques. Robotic-assisted procedures offer benefits in term of clinical outcomes, but their advantages on pulmonary recovery and quality of life have not yet been distinctly prospectively studied.
Methods Eighty-six patients undergoing lobectomy over a period of 29 months were prospectively studied for their pulmonary function recovery and pain score level during the in-hospital stay and at 1, 2, and 6 months. Quality of life was evaluated at 2 and 6 months. Forty-five patients were operated by posterolateral limited thoracotomy and 41 patients by robotic approach. The postoperative analgesia protocol differed for the two groups, being lighter for the robotic group.
Results The pulmonary tests were not significantly different during the in-hospital stay. At 1 month, the forced expiratory volume in 1 second, forced vital capacity, vital capacity, and maximal expiratory pressure were significantly better for the robotic group (p = 0.05, 0.04, 0.05, and 0.02, respectively). There was no significant difference left at 2 and 6 months. Pain intensity was equivalent during the in-hospital stay but was significantly lower for the robotic group at 1 month (p = 0.02). At 2 and 6 months, pain and quality of life were comparable.
Conclusion Robotic technique can offer similar pulmonary and pain recovery during the in-hospital stay with a lighter analgesia protocol. It clearly favors the early term recovery compared with the open limited technique. The objective and subjective functional recovery becomes equivalent at 2 and 6 months.
Management of Cutaneously Exposed Carotid Stents in Recurrent and Unresectable Head and Neck Cancer
Authors: Beer-Furlan André , Heilingoetter Ashley , Rayle Christopher , O'Toole Thomas , Nielsen Thomas J. , Crowley Richard Webster , Al-Khudari Samer 
Published: October 2020

AbstractObjective Carotid blowout syndrome (CBS) is a rare but potentially life-threatening complication of head and neck cancer (HNC) treatment. Patients with CBS are managed with covered stents, limited published information exists regarding the management of delayed complications, specifically cutaneous exposure of stents. Here, we present our experience managing cutaneously exposed carotid artery stents (CAS) in patients with recurrent and unresectable HNC.Methods A single-institution retrospective analysis was performed to identify recurrent HNC patients who underwent CAS placement for CBS and complicated with cutaneous exposure of the stent between 2014 and 2016. Medical records were reviewed with attention to treatment history, pre-, intra-, and postoperative courses, anticoagulation needs, and durability of the reconstruction.Results We identified three patients who presented with a right CAS fully exposed in a large, ulcerative wound. All patients underwent a right pectoralis major myocutaneous flap (PMMF) to cover the exposed stent within 30 days of presentation to our institution. Two of three patients attained adequate coverage of the stent for more than 30 days, while one experienced partial flap dehiscence within 12 days. Two patients developed postoperative chest hematomas, which were managed conservatively. Two of three patients were able to undergo further palliative adjuvant treatments within 60 days of the initial surgical procedure.Conclusion In this small series, durable coverage of an exposed carotid artery with PMMF was successful in two of three patients with extensive disease burden and complex prior treatment history. No mortalities occurred within 30 days postoperatively.
Multifunctional oxides for topological magnetic textures by design
Authors: Lim Z S , Ariando A 
Published: October 2020

Abstract
Several challenges in designing an operational skyrmion racetrack memory are well known. Among those challenges, a few contradictions can be identified if researchers are to rely only on metallic materials. Hence, expanding the exploration of skyrmion physics into oxide materials is essential to bridge the contradicting gap. In this topical review, we first briefly revise the theories and criteria involved in stabilizing and manipulating skyrmions, followed by studying the behaviors of dipolar-stabilized magnetic bubbles. Next, we explore the properties of multiferroic skyrmions with magnetoelectric coupling, which can only be stabilized in Cu2OSeO3 thus far, as well as the rare bulk Néel-type skyrmions in some polar materials. As an interlude section, we review the theory of the anomalous and topological Hall effect (THE), before going through the recent progress of THE in oxide thin films. The debate about an alternative interpretation is also discussed. Finally, this review ends with a future outlook regarding the promising strategies of using interfacial charge transfer and (111)-orientation of perovskites to benefit the field of skyrmion research.
Body-size-dependent Iodine-131 S values
Authors: Yeom Yeon Soo , Griffin Keith , Shin Bangho , Choi Chansoo , Han Haegin , Moon Sungho 
Published: October 2020

Abstract
In a recent epidemiologic risk assessment on late health effects of patients treated with radioactive iodine (RAI), organ/tissue doses of the patients were estimated based on iodine-131 S values derived from the reference computational phantoms of the International Commission on Radiological Protection (ICRP). However, the use of the S values based on the reference phantoms may lead to significant biases in the estimated doses of patients whose body sizes (height and weight) are significantly different from the reference body sizes. To fill this critical gap, we established a comprehensive dataset of body-size-dependent iodine-131 S values (rT ← thyroid) for 30 radiosensitive target organs/tissues by performing Monte Carlo dose calculations coupled with a total of 212 adult male and female computational phantoms in different heights and weights. We observed that the S values tend to decrease with increasing body height; for example, the S value (gonads ← thyroid) of the 160 cm male phantom is about 3 times higher than that of the 190 cm male phantom at the 70 kg weight. We also observed that the S values tend to decrease with increasing body weight for some organs/tissues; for example, the S value (skin ← thyroid) of the 45 kg female phantom is about two times higher than that of the 130 kg female phantom at the 160 cm height. For other organs/tissues, which are relatively far from the thyroid, in contrast, the S values tend to increase with increasing body weight; for example, the S value (bladder ← thyroid) of the 45 kg female phantom is about 2 times lower than that of the 130 kg female phantom. Overall, the majority of the body-size-dependent S values deviated to within 25% from those of the reference phantoms. We believe that the use of body-size-dependent S values in dose reconstructions should help quantify the dosimetric uncertainty in epidemiologic investigations of RAI-treated patients.
Heated thin film gauge arrangements to reduce uncertainty in transient heat transfer measurements
Authors: Usandizaga Inés , Beard Paul , Chana Kam , Povey Thomas 
Published: October 2020

Abstract
This paper describes the development of heated double-sided thin film gauge configurations for transient heat transfer measurements. By heating the substrate it is possible to measure the heat flux over a range of surface temperatures and deduce the adiabatic wall temperature and the external heat transfer coefficient. The accuracy of the measurement depends on the stability of the regression of heat flux against wall temperature and can be improved by extending the range of wall temperature over which the regression is performed. In this paper we compare two methods of local heating: double-sided gauges with an underside thin film heater and self-heating double-sided gauges. Both arrangements have been used in the Oxford Turbine Research Facility to measure the heat transfer on the uncooled turbine shroud of the MT1 high-pressure turbine stage at engine-representative conditions. These measurements yield improved regressions compared to conventional techniques to determine the adiabatic wall temperature and the heat transfer coefficient.