bluuebunny/crossref_metadata_2025 huggingface dataset:
Mechanical and physical properties of aluminium-silicon (Al-Si) casting alloys reinforced by Zinc Oxide (ZnO)
Authors: Puspitasari Poppy , Soepriyanto Okky Rachmadilla , Sasongko Muhammad Ilman Nur , Dika Johan Wayan , Andoko
Published: September 2018

This study aimed to enhance the properties of aluminium-silicon (Al-Si) alloys by adding zinc oxide as a reinforcing material. This study was a type of pre-experimental design called the one-shot case study, in which sample groups subjects were given treatments and then observed. The steps included melting the aluminium-silicon in a furnace at 900° C, adding a certain amount of zinc oxide (0.05%, 0.1%, or 0.2%), stirring the mixture for 1 minute, and pouring it into a permanent mould. Results showed that, among the three specimens, the specimen reinforced with 0.2% zinc oxide had the highest tensile strength of 23.9 kg/mm2, the greatest hardness of 134.4 HV, and a flat surface with evenly distributed grains and more brittle fracture.
Phase separation on ricinoleic acid freezing
Authors: Firman  , Hasan Barlian , Anshar Muhammad
Published: September 2018

Phase separation material essentially influence storage capacity or heat release. Ricinoleic acid is potential to be used as a heat storage material. However, the nature of the phase separation of the material has not been studied yet. Therefore, this research was aim to determine the nature of the material. The test of characteristics of heat fusion and crystallization temperature of the material are carried were examined by using differential scanning calorimetry (DSC). The test was carried out using 15-20 mg of ricinoleic acid with cooling rate of 2°C/min, 3°C/min, 4°C/min, 5°C/min, 10°C/min, and 15°C/min. Coagulation testing was done by using a digital microscope of data aquisition. For comparison, characterization on oleic acid was also done. The result that hydroxyl functional group affects the occurrence of phase separation on the ricinoleic acid freezing process.
Analyze the effect of phosphorus on the mechanical properties and microstructure on cast iron
Authors: Sambas Achmad , Gamawan Ananto , Gunara Sophiadi
Published: September 2018

Cast Iron FC250 with phosphorus alloy is used as electrode connector in the aluminum electrolysis process at PT. Indonesia Asahan Aluminium (Inalum), that is used to connect the rod with carbon anode. It will be crushed after the carbon anode dimension is reduced, that takes approximately 30 days. In order to make crushing process easier, phosphorus alloy then added into such FC250. The objective of the study is determining phosphorus effect on FC 250. The methodology consists of determine the test specimens, initiate such specimen of casting by varying the amount of phosphorus percentage of 0.3%, 0.5%, 0.7% and 0.9%, then perform mechanical testing and microstructure observation on each specimen. The result is, as the percentage of phosphorus in FC 250 increased, so its hardness value whereas the value of the tensile strength even decreased. Form the microstructure point of view, the “steadit” increased as well in line with the rise of phosphorus.
Fiberglass reinforced plastic as construction material for Indonesian fishing vessels – challenges and future potential development
Authors: Wibawa I Putu A. , Birmingham Richard W.
Published: September 2018

The continuous increase in the use of wood in many sectors and the growing concerns on the sustainability of the forest products has raised serious questions as to the sustainability of wood as a construction material for fishing vessels in Indonesia. Based on the current developments, Fiberglass Reinforced Plastic (FRP) material is potentially the top alternative substitute to wood for building fishing vessels in Indonesia. However, the initiatives to introduce FRP, particularly by the Indonesian government, as alternative construction material still have many problems including that of acceptance by the fishers themselves. The result of the study shows that some aspects that need to be developed for implementing FRP as construction material in the future, including: fishers’ knowledge and experiences regarding to FRP as construction material, the suitable design of the FRP fishing vessels for specific fishing communities and proper infrastructure to support the FRP boats industries.
Analisys of casting defects and mechanical properties on Al-Si alloys using Bangkalan local clays as sand casting binder
Authors: Syaifullah Candi Galih , Saputra Ayik Bela , Shabrina Ruhyatul F , Puspitasari Poppy
Published: September 2018

This research is aimed to know the defect of castings, tensile strength, and hardness of Al-Si alloy to the variation of binder. The research method used is descriptive quantitative research method. This beacuse the data is expressed in the form of numbers. This research uses pre-experimental research design using one-shot case study model. Based on the results of the study, it was found that most pinhole defects were owned by specimens using 90% bentonite binder that is 59 defects. Whereas the pinhole defect which is at least owned by the specimens using banngkalan local clay binder 9% that is 31 defects. The most common open grain structure defect is owned by metal casting specimens using a 9% bentonite binder, which is 81 defects. Whereas the defect of open grain structure is at least owned by the specimen result of casting of metal clad with bangkalan local clay 3% which amounted to 40 defects. The result of the research using bangkalan local clay binder of 9% has higher tensile strength than other binder. This is because the characteristic of bangkalan local clay which has a high content of calcium (Ca) is 92,81%. The value of the tensile strength of the bangkalan local clay is 12,8712 (kg/mm2), whereas the bentonite which is said to be the ideal binder for the mold has a tensile strength of 10,1612 (kg/mm2). The highest hardness value is owned by Al-Si alloy casting specimen with bend mixture variation of bangkalan local clay 9% that is 128,033 HV. While the lowest hardness value is owned by Al-Si alloy casting foundry with 9% bentonite binder 114,4 HV.
The potential of silk fibroin as a polymer composite reinforcement for bone implant materials
Authors: Purnomo  , Hadi Setyarini Putu , Hidayati Mukaromah Ana
Published: September 2018

Silk fibroin is an outstanding material because of their biocompatible and excellent mechanical properties. This review article is focused on silk fibroin and silk fibroin-based composites that are used as biomaterials and their potential for composite reinforcing materials for artificial bone engineering. This material is chosen because it is biocompatible, low biodegradable, as well as ease of fabrication, as well as a variety of good mechanical behavior. The first part provides the introduction of some polymer-based materials used as biomaterials. The second part is more focused on silk fibroin applications as biomaterials that include silk fibroin structure, biocompatibility, degradation, immunological responses, sterilizability, drug delivery for osteogenesis, and fibroin reinforcement materials silk.
Growth of anodic Aluminum Oxide using titanium as cathode – a review
Authors: Setyarini Putu Hadi , Gapsari Femiana , Purnomo
Published: September 2018

Aluminum is a material with a variety of uses in various fields because this material is easy to obtain, can be made in various ways and has good corrosion resistance. Now this material begins to be studied and applied to the realm of biomaterials, with the use of the membrane of the aluminum oxide layer on the body of living things began to be applied. In this paper further elaborated on the use of titanium alloys as cathodes in the aluminum anodizing process. Deep discussion is emphasized on the growth process of the oxide layer that occurs during the anodizing process, where the oxide layer consists of a barrier layer and a pore layer. During the process, not only does the oxide layer grow with time but also the appearance of voids in the pore lining wall. In the final result, it was found that titanium was able to penetrate the oxide layer formed during the anodizing process. As for future applications, it is expected that the anodizing material is expected to be an alternative material in the field of biomaterial replacement
Heat treatment effect on metal matrix composite with brass matrix and fly ash
Authors: Aminnudin Aminnudin , Choiron Moch. Agus
Published: September 2018

Metal matrix composite (MMC) is a combination of two or more materials using metal as a matrix. In this paper we used brass as the matrix and fly ash as for the particle. The fly ash used is fly ash which is produced from coal combustion in the Paiton power plant. Fly ash composition in the MMC are 5% and 10%. The MMC was produced with gas furnace. Heat tratment to MMC was done at 350 and 400 °C.Hard testing process, tensile test and impack test are carried out at MMC before heat treatment and after heat treatment. From the test results showed an increase in hardness, tensile strength and impact test showed the heat treatment process at a temperature of 350 °C. Heat treatment at a temperature of 400 °C does not improve the mechanical properties of MMC
Study the effect of angle of attack on flow characteristics at racing bike helmet using CFD
Authors: Syamsuri  , Hasan Syafik M , Iswanto Yudho Putro
Published: September 2018

At a cyclist drag racing champions greatly affect the speed of the bike, especially on the use of racing bike helmets. If the aerodynamic force from the racing bike helmet is getting smaller than the use of helmets on the bike racing will be more optimal and will affect the rate of the racer. In this study, numerical simulations were used to investigate the magnitude of the drag force that occurs around the surface of the helmet. With CFD software, 4 variations of attack angle 0°, 10°, 20° and 30° and variations of Reynold number 7.14x104, 1.00x105, and 1.16x105 are simulated to determine the flow characteristics of each state. The simulation results show that large area vortex is formed at the bottom of the helmet curve and dominates at the attack angle 30°. The result of the drag coefficient generated at the angle of attack 0° to 20° tends to decrease but at the attack angle 200 and 30° the drag coefficient increases.
Enhancement of shearography-based damage identification using best tree wavelet packet analysis
Authors: Katunin Andrzej , Lopes Hernani , dos Santos José Viriato Araújo
Published: September 2018

Shearography found many industrial applications as a non-destructive testing method due to its high spatial resolution and contactless measurements. However, to detect small structural damage, shearography should be enhanced by applying advanced signal processing methods to results of experimental testing. In this paper, the authors present an enhanced method based on the best tree wavelet packet analysis, which allows for extraction of the most informative nodes from the 2D wavelet packet decomposition tree. The proposed method is more effective than typical wavelet transforms due to its ability of adaptive selection of the best basis. The efficiency of the method was verified experimentally on damaged plates. The obtained results clearly show high sensitivity to the introduced small damage, which make the method attractive for industrial applications.
Effect of friction welding conditions on tensile strength and hardness of AISI 310 stainless steel joints
Authors: Iswar Muhammad , Nur Rusdi
Published: September 2018

This study aims to determine the effect of rotational speed and forging time on tensile strength and hardness through the friction welding process of stainless steel AISI 310. The research was carried out by friction welding process by using the lathe machine with varying rotational speed (550, 1020 and 1800 rpm), forging time (25, 35, 45 seconds), and welding temperature of 1050°C ± 10°. Axial pressure was obtained through the addition of a hydraulic system to the release head of a lathe machine with a forging pressure of 123.8 N/mm2. Furthermore, the friction welding results were tested mechanically by conducting the tensile and hardness tests. The experimental results showed that the highest tensile strength of the friction welding result of 706,61 N/mm2 was obtained at 1800 rpm and 45 seconds, and this value is lower when compared with raw material (780,25 N/mm2). The highest hardness value (61.5 HRC-A) was located on the welded joint section with 550 rpm of rotational speed and 25 seconds of forging time. The hardness of the parent metal is 69.45 HRC-A. The rotational variation influences the hardness value, the higher the rotational speed will increase the hardness. The longer of forging time will decrease the hardness.
GECOBRIDGE: A concept of a smart eco-friendly integrated bridge utilizing geopolymer and graded concrete technology
Authors: Pratama M. Mirza Abdillah , Pratiwi Yustika Dyah , ’Ilmi Miftah Aliyil , Mahardika Alifah
Published: September 2018

The development of geopolymer concrete technology was initially inspired by environmental issues from the use of cement as one of the main constituents in concrete that contribute to the major greenhouse gas emissions on earth. The utilization of fly ash is expected to reduce cement in concrete so that the effects of environmental pollution can be minimised. Fly ash is a by-product of coal combustion available abundantly in hundreds of coal-fired power plant spread all over Indonesia which also could become a source of the environmental pollutant. The integration of graded concrete technology along with geopolymer concrete can create high-performance structural elements while still being cost efficient. Currently, research development related to geopolymer concrete and graded concrete is potentially applied to public infrastructures such as bridges that can support the economic activities of local people. The application of porous asphalt and an integrated drainage system make GECOBRIDGE become concepts of a smart, efficient, and environmentally friendly bridge, both in terms of construction, operation, and maintenance. GECOBRIDGE is expected to become a bridge that can conserve water through rain harvesting so that it can be utilized for the cultivation of a hydroponic farm in the upstream area.
Effect of concession model and deregulation logistics policy for increasing port customer satisfaction in Indonesia
Authors: Sirajuddin  , Sunaryo  , Zagloel T. Yuri
Published: September 2018

This paper analyzes the effect of port concession and the deregulation of logistics policy implementation on port customer satisfaction. This research uses 5 latent variables and 18 manifest / indicator variables which are described in the form of Likert scale questionnaires distributed to Port Customers in Indonesia which are freight forwarder, import-export companies and port operators. From SEM structural equations and model measurement results, it can be concluded that the effect of concession and deregulation logistics policy on the overall customer satisfaction is acceptable and data support the model. Port concession variable has positive path coefficient of 0.88 and t statistic of 5.86 > 1.96. Infrastructure and Superstructure Variable has positive path coefficient of 0.61 and t statistic of 3.66 > 1.96 deregulation logistics policy Variable has positive path coefficient of 0.24 with t statistic of 2.04 > 1.96. Integration System Technology Variable has positive path coefficient of 0.21 with t statistic of 2.39 > 1.96 so it can be concluded that the overall hypothesis can be accepted and data supports the model.
Hardness analysis on carburized steel weld joint by SMAW using different welding current
Authors: Pradana Yanuar Rohmat Aji , Wahono  , Tanzila Dicky , Lukman Azmi
Published: September 2018

Low-cost weld joint on wear-resist gear train component was introduced for replacing conventional bolted connection to avoid its additional material and holes requirement. This study was concerned on the hardness analysis of carburized steel weld joint generated from SMAW with different welding currents, namely 80, 100, and 120 A. The results indicated that the hardness is decreased at HAZ and subsequently increased at weld metal for all samples. On the other hand, the highest welding current applied during welding shows the highest hardness curve among the other currents up to 226.5±2 HV at weld metal. By micro-and macrostructural analyses, phases evolution during thermal cycle on welding process played the crucial role to determine the hardness of HAZ, while the weld metal hardness was dominantly driven by the carbon-rich element distribution.
Estimation of calcaneal deformation while standing from the boolean operation between 3D and footprint image and its comparison with lateral x-ray
Authors: Wibowo Dwi Basuki , Suprihanto Agus , Widodo Achmad , Haryadi Gunawan Dwi
Published: September 2018

Load and deformation in the calcaneal/heel region are often studied because of their potential for pain. Research conducted before proved that the calcaneal region receives large loads, both standing and walking, mainly due to excessive body weight. While heel pad deformation is not always associated with body weight, but its influenced by the mechanical properties of plantar soft tissues. In the older person the deformation of the calcaneal region while standing is lower than the adult person, which indicates the loss of the elasticity of the heel pad in aged adults. The aim of this study is estimating deformation of calcaneal area while standing from the Boolean Operation between 3D and footprint image of foot which is a novelty. Thirteen patients who feel pain due to calcanea spur were asked to volunteer research (3 males and 10 females, age 56 ±10 years old, and BMI 25.53±3.74 kg/m2). The 3D image is obtained from 3D scanner for foot orthotics, while the 2D footprint image is obtained from the digital footprint scanner. To determine the accuracy of this method compared with the deformation result of lateral x-rays due to its own weight.
Development model of train rescheduling model consider predictive delay
Authors: Iswardani Kurnia , Rusdiansyah Ahmad
Published: September 2018

Delay on the train is caused by some disturbance that occurs on the train or at the station, such as a broken train engine, broken train line signals, and others. The train operator at the station will reschedule the train schedule in the event of a delay. Currently, the train only reschedules when the delay occurs on the spot, consequently the rescheduling determination takes a long time. This can be anticipated by taking preventive action, ie rescheduling by using predictive delay. Possible conflicts that will occur when rescheduling single track are overtaking and crossing. This research will focus on the development of rescheduling considering predictive delay. The purpose of this study is to minimize the total delay time. The output of this research is a decision support tool that can generate free-conflict timetable when delay occurs.
Vehicle Routing Problem (VRP) for courier service: A review
Authors: Purnamasari Citra Dewi , Santoso Amelia
Published: September 2018

The internet development access is really very fast and change all aspects for life activities include buying and selling transactions of goods or services that can arrange online or also called e-commerce which courier service influence. The courier basic operational is logistics of a supply chain. Transportation is a vital component in logistics management because it becomes the largest cost component in its activities that is about 50-60% of the total logistics costs. The purpose of this study is to find out what kind of vehicle routing problem (VRP) is used for courier service so can be used as reference for further research. Collect and selection process found 40 science journals for analyse. There has been a lot of research about the shortest route problem for courier service or can also called city logistics with VRP which the optimum solution obtained with heuristic and metaheuristic algorithm. Result found VRP type often used for courier service are dynamic VRP (DVRP) and VRP with time window (VRPTW) or can merging both dynamic VRP with time window (DVRPTW).
Job shop scheduling considering material handling process
Authors: Pakpahan Eka K.A. , Kristina Sonna , Setiawan Ari , Merlians Evelin
Published: September 2018

This paper discussed job shop scheduling considering material handling process. This process is a very important aspect on a flexible manufacturing system, where raw material or semi-finished goods are delivered from one processing point unto another by utilizing automated material handling equipment, functioned as shared resources. The starting time of each process is affected by the ability of the material handling equipment to conduct timely delivery from one point to another, therefore considering this process unto scheduling is important to enable planner to get precise estimation of the process makespan. We take the case where the flexible manufacturing system is consisted of four identical machines; each has the capability of processing various jobs due to the various cutting tools installed on their tools magazine. Jobs are dispatched based on longest processing time rule and then allocated to machine which has minimum load. Being a shared resource, material handling equipment has pick-up and delivery priority rule when handling multiple requests. The two most common rules are longest waiting and closest entity. This paper will analyzed the impact of each rule to the process makespan and material handling equipment utilization. Simulation model were built using Promodel to give decision maker better visualization of the system under consideration.
Failure simulation of connecting rods without pistons using finite element method
Authors: Andoko  , Saputro Nanang Eko
Published: September 2018

The combustion of fuel takes place inside the cylinder with the oxygen of the air, producing a very high-pressure combustion gas. The combustion gas does work on the piston and then passes through the connecting rod to the crankshaft. The reciprocating translational motion of the piston may damage the connecting rod. A simulation using ANSYS was performed on each of the three connecting rod materials. Results showed that the maximum deformation occurred in the connecting rod made of structural steel, aluminium alloy, and titanium alloy was 0.239 mm, 0.672 mm, and 0.496 mm, respectively.
Effects of DP steel microstructure on the disappearance of discontinuous yielding
Authors: Basoeki Prita Dewi
Published: September 2018

Although in terms of quality is not as high as TRIP steel, DP steel has been developed as an option to meet the minimum standard industrial requirement for automotive. Steel development for automotive material leads to posses high strength without suffering its ductility and weld ability, in addition there is no appearance of discontinuous yielding that cause stretcher strain marking. The change of micro structure as a result of the intercritical annealing process not only increases the strength of Dual Phase Steel, but also eliminates the discontinuous yielding. The phenomenon of discontinuous yielding is no longer appear in Dual Phase Steel which heating time on intercritical annealing process more than 1 minute, the minimum time is equal to the disappearance of discontinuous yielding. The phenomenon of upper yield point and discontinuous yielding on carbon steel is strongly influenced by the magnitude of the stress acting on the Ferrite phase to move the dislocation of the pinned state by the interstitial atom. From the recent works gives the result that the disappearance of discontinuous yielding in Dual Phase Steel resulting from the intercritical annealing process makes Dual Phase Steel very suitable as an automotive material.
Experimental investigation of design parameters for laboratory scale Pelton wheel turbine using RSM
Authors: Permanasari Avita Ayu , Ainul Yaqin Fajri Faizal , Wulandari Retno , Sukarni  , Puspitasari Poppy
Published: September 2018

Response Surface Methodology (RSM) is used in this study as an experimental design to obtain optimum conditions for each parameter. This study uses pelton turbines on a laboratory scale. The purpose of this study is to determine the optimum number of buckets and flow rates against turbine performance. The performance measured in this study is turbine efficiency. RSM is used to obtain mathematical equations from the performance of the turbine at optimum conditions. The optimum results obtained from RSM is to improve the performance of Pelton turbines that are 15,7714 (16 pieces) and flow rate of 0.1583 ℓ / s (0.16 ℓ / s) resulting in turbine efficiency of 29.16%.
Effet de l’addition de TiB2 sur les propriétés mécaniques et tribologiques de revêtements NiCrBSi déposés par projection thermique
Authors: Kazamer Norbert , Kossman Stephania , Baranyi István , Chicot Didier , Serban Viorel-Aurel , Rajnai Zoltán , Voda Mircea
Published: September 2018

L’influence de TiB2 dans des revêtements à base nickel est étudiée du point de vue microstructurale (identification des phases et mesure de la porosité), mécanique (dureté et module d’élasticité par indentation instrumentée) et du comportement mécanique (résistance au frottement par usure pion/disque). Dans les deux revêtements à 2,5 et 10 % de TiB2, on note la présence de siliciures, carbures et borures mais uniquement la présence d’oxyde de titane pour la teneur à 10 %. La porosité est plus élevée (6 %) lorsque la teneur en TiB2 est plus petite, elle est de 1,2 % pour l’autre revêtement. Après une discussion sur l’effet de taille et l’influence de la porosité sur la mesure des propriétés par indentation, la dureté est trouvée sensiblement la même dans les deux cas, autour de 3 GPa, alors que le module d’élasticité semble plus élevé (175 GPa au lieu de 150 GPa) pour la teneur la plus élevée en TiB2. Enfin, le coefficient de frottement est plus grand dans la zone de transition ou de rodage avant d’atteindre la même valeur moyenne de 0,6 dans le régime stationnaire.
Second-order sensitivity analysis for parametric equilibrium problems in set-valued optimization
Authors: Anh Nguyen Le Hoang
Published: September 2018

In the paper, we first establish relationships between second-order contingent derivatives of a given set-valued map and that of the weak perturbation map. Then, these results are applied to sensitivity analysis for parametric equilibrium problems in set-valued optimization.
A linear programming based approach for composite-action Markov decision processes
Authors: Zhang Zhicong , Li Shuai , Yan Xiaohui , Zhang Liangwei
Published: September 2018

We study a time homogeneous discrete composite-action Markov decision process (CMDP) which needs to make multiple decisions at each state. In this particular Markov decision process, the state variables are divided into two separable sets and a two-dimensional composite action is chosen at each decision epoch. To solve a composite-action Markov decision process, we propose a novel linear programming model (Contracted Linear Programming Model, CLPM). We show that the CLPM model obtains the optimal state values of a CMDP process. We analyze and compare the number of variables and constraints of the CLPM model and the Traditional Linear Programming Model (TLPM). Computational experiments compare running times and memory usage of the two models. The CLPM model outperforms the TLPM model in both time complexity and space complexity by theoretical analysis and computational experiments.
A computationally efficient algorithm to approximate the pareto front of multi-objective linear fractional programming problem
Authors: Stanojević Bogdana , Stanojević Milan
Published: September 2018

The main contribution of this paper is the procedure that constructs a good approximation to the non-dominated set of multiple objective linear fractional programming problem using the solutions to certain linear optimization problems. In our approach we propose a way to generate a discrete set of feasible solutions that are further used as starting points in any procedure for deriving efficient solutions. The efficient solutions are mapped into non-dominated points that form a 0th order approximation of the Pareto front. We report the computational results obtained by solving random generated instances, and show that the approximations obtained by running our procedure are better than those obtained by running other procedures suggested in the recent literature. We evaluated the quality of each approximation using classic metrics.
The Value of Detailed First-Trimester Ultrasound Anomaly Scan for the Detection of Chromosomal Abnormalities
Authors: Tekesin Ismail
Published: September 2018

Purpose To evaluate the performance of first-trimester ultrasound screening involving a detailed anomaly scan for the detection of trisomy 18, trisomy 13, triploidy, Turner syndrome and trisomy 21.

Methods Data of pregnant women who underwent aneuploidy screening at 11–13 weeks of gestation was retrospectively analyzed. Crown-rump length (CRL), fetal nuchal translucency thickness (NT) and nasal bone (NB) anatomy, blood flow across the tricuspid valve (TV) and through the ductus venosus (DV) were assessed. Furthermore, a detailed scan for fetal anatomical anomalies (FA) was carried out. Performance of these markers was assessed by logistic regression and ROC analyses for different screening models.

Results 4005 fetuses were analyzed. 3856 were euploid, 149 aneuploid (trisomy 18: 40; trisomy 13: 14; triploidy: 3; Turner syndrome: 17; trisomy 21: 75 cases). 70–100 % of the fetuses with trisomy 18 and 13, triploidy and Turner syndrome but only 34.7 % with trisomy 21 had at least one fetal defect. Considering all aneuploidies, the detection rate (DR) for screening based on MA+NT+NB+TV+DV was 90.6 % and improved to 96.0 % if an FA was added (fixed false-positive rate: 3 %). If screening was based on MA+NT+FA, the detection rate for all aneuploidies was 85.2 %. However, the DR for trisomy 18, trisomy 13, triploidy and Turner syndrome (excluding trisomy 21) was 94.6 %, indicating the high diagnostic value of an anomaly scan for these aneuploidies.

Conclusion Incorporation of a detailed fetal anomaly scan (FA) into first-trimester screening algorithms can improve the detection rates for trisomy 18 and 13, triploidy and Turner syndrome.
Practical Deoxygenation of Oxazole N-Oxides by PCl3/Collidine
Authors: Shirinian Valerii , Lonshakov Ilya , Zakharov Alexey , Lvov Andrey , Krayushkin Mikhail
Published: September 2018

A new chemoselective method for the synthesis of 2-aryl-1,3-oxazoles by deoxygenation of the corresponding N-oxides has been developed. As the deoxygenation reagent, a previously unknown complex of collidine with phosphorus trichloride in a 2:1 ratio has been used. The developed method enabled the preparation of a wide range of 2-aryl-1,3-oxazoles comprising various functional groups in good yields. The advantage of this reagent is its tolerance to nitro, methyl, hydroxyl, formyl, and acetyl groups, and double bonds. Due to chemoselectivity and availability of reagents, the method may be used for deoxygenation of N-oxides of other heterocyclic compounds (thiazole, pyridine, quinoline, etc.).
Prologue: Atropisomerism
Authors: Siegel Jay
Published: September 2018

Jay S. Siegel received his Ph.D. from Princeton (1985), was a Swiss Universities Fellow at ETH Zurich (1983-4), and NSF–CNRS postdoctoral fellow at the University of Louis Pasteur in Strasbourg (1985-6). He began as Assistant Professor of Chemistry (1986) at UCSD, was promoted to Associate Professor (1992) and Full Professor (1996). In 2003, he was appointed as Professor and co-director of the Organic chemistry institute of the University of Zurich (UZH) and Director of its laboratory for process chemistry research (LPF). He served as Dean of Studies and Head of the Research Council for the Faculty of Sciences at UZH. He moved to Tianjin University in 2013 as dean, and joined the Schools of Pharmaceutical and Life Sciences into a new Health Science Platform. His research is in the area of Stereochemistry and Physical Organic Chemistry.
Synthesis of Isoquinoline-Fused Quinazolinones through Ag(I)-Catalyzed Cascade Annulation of 2-Aminobenzamides and 2-Alkynylbenzaldehydes
Authors: Koketsu Mamoru , Sonawane Amol , Shaikh Yunnus , Garud Dinesh
Published: September 2018

A new route for the expedient synthesis of a specific regioisomer of isoquinoline-fused quinazolinones is reported. Silver(I)-catalyzed cascade cyclization of 2-aminobenzamides and 2-alkynylbenzaldehydes followed by in situ oxidation gives 12-butyl- or 12-aryl-6H-isoquinolino[2,1-a]quinazolin-6-ones in 69–91% yields. The structure of the isoquinoline-fused quinazolinone was confirmed by X-ray crystallography analysis.
N-Oxide-Controlled Chemoselective Reduction of Nitrofuroxans
Authors: Fershtat Leonid , Bystrov Dmitry , Zhilin Egor , Makhova Nina
Published: September 2018

A facile and chemoselective SnCl2-mediated mild reduction of regioisomeric 3- and 4-nitrofuroxans for the synthesis of amino­furazans and aminofuroxans in good yields is developed. Reduction of 4-nitrofuroxans results in the selective formation of 4-aminofuroxans, while analogous reduction of 3-nitrofuroxans affords 3-aminofurazans as a result of simultaneous reduction of the nitro group and exocyclic N–O bond.
Interpreting Osteogenesis Imperfecta Variants of Uncertain Significance in the Context of Physical Abuse: A Case Series
Authors: Canter Jennifer , Rao Vinod , Palusci Vincent , Kronn David , Manaster Michal , Altman Robin
Published: September 2018

Unexplained childhood fracture(s) warrant consideration of physical abuse and osteogenesis imperfecta (OI). Genetic OI testing may identify “variants of unknown significance (VUS).” Interpretation of VUS in context of potential abuse may have protective, criminal, and medical impacts. This case series explores practices regarding clinicians' interpretation of VUS during child abuse evaluations. Variability was noted regarding factors considered for interpreting clinical significance. Based on these cases, recommendations for careful and thorough evaluation are detailed, including proposed use of a limited follow-up skeletal survey in 3 months, as a consideration to assess healing of prior fractures and to look for any additional injuries.
On the estimation of the Mori-Zwanzig memory integral
Authors: Zhu Yuanran , Dominy Jason M. , Venturi Daniele
Published: September 2018

We develop a thorough mathematical analysis to deduce conditions for the accuracy and convergence of different approximations of the memory integral in the Mori-Zwanzig (MZ) equation. In particular, we derive error bounds and sufficient convergence conditions for short-memory approximations, the t-model, and hierarchical (finite-memory) approximations. In addition, we derive useful upper bounds for the MZ memory integral, which allow us to estimate a priori the contribution of the MZ memory to the dynamics. Such upper bounds are easily computable for systems with finite-rank projections. Numerical examples are presented and discussed for linear and nonlinear dynamical systems evolving from random initial states.
Parallel 2D FFT implementation on FPGA suitable for real-time MR image processing
Authors: Li Limin , Wyrwicz Alice M.
Published: September 2018

We report the design and implementation of a parallel two-dimensional fast Fourier transform (2D FFT) algorithm on a Field Programmable Gate Array (FPGA) for real-time MR image processing. Although a number of architectures of 2D FFT hardware processors have been reported, these generic processors or IP cores are not always effective for processing MRI data. The key feature of our design is that our processors are customized solely for real-time MRI applications. We demonstrate that by considering the unique features of real-time MRI data streams, we were able to develop and implement the 2D FFT processors that are resource-efficient and flexible enough to handle both regular and irregular data. Using a data-driven approach, we were able to simplify the inter-processor data communication while maintaining data synchronization without a synchronous clock signal bus and complex interconnection network. We experimentally verified our designs by processing multi-slice image data sets with 128 × 128 and 256 × 256 in-plane resolution. The results demonstrate the effectiveness of our 2D FFT processors and show that image reconstruction can be accelerated in proportion to the parallel processing factor. We achieved image-reconstruction processing rates up to 3000 and 800 slices per second for images with 128 × 128 and 256 × 256 in-plane resolution, respectively. The results also indicate that the image-reconstruction acceleration is primarily limited by the speed of the data transfer between the FPGA device and external sensors.
AGES: Automated Gas Environment System for in situ neutron powder diffraction
Authors: Kirkham Melanie , Heroux Luke , Ruiz-Rodriguez Mariano , Huq Ashfia
Published: September 2018

High fluxes available at modern neutron and synchrotron sources have opened up a wide variety of in situ and operando studies of real processes using scattering techniques. This has allowed the user community to follow chemistry in the beam, which often requires high temperatures, gas flow, etc. In this paper, we describe an integrated gas handling system for the general-purpose powder diffraction beamline Powgen at the Spallation Neutron Source. The Automated Gas Environment System (AGES) allows control of both gas flow and temperature (room temperature to 850 °C), while measuring the partial pressure of oxygen and following the effluent gas by mass spectrometry, concurrent with neutron powder diffraction, in order to follow the structural evolution of materials under these conditions. The versatility of AGES is illustrated by two examples of experiments conducted with the system. In solid oxide fuel cell electrode materials, oxygen transport pathways in double perovskites PrBaCo2O5+δ and NdBaCo2O5+δ were elucidated by neutron diffraction measurements under atmosphere with oxygen partial pressures (pO2) of 10−1 to 10−4 (achieved using mixtures of nitrogen and oxygen) and temperatures from 575 to 850 °C. In another example, the potential oxygen storage material La1−xSrxFeO3 was measured under alternating flows of 15% CH4 in N2 and air (20% O2 in N2) at temperatures from 135 to 835 °C. From the oxygen stoichiometry, the optimal composition for oxygen storage was determined.
WAND2—A versatile wide angle neutron powder/single crystal diffractometer
Authors: Frontzek M. D. , Whitfield R. , Andrews K. M. , Jones A. B. , Bobrek M. , Vodopivec K. , Chakoumakos B. C. , Fernandez-Baca J. A.
Published: September 2018

Wide Angle Neutron Diffractometer Squared is a high-flux versatile diffractometer with a 2-Dimensional Position Sensitive Detector at the High Flux Isotope Reactor. The instrument has strengths in both powder and single crystal diffraction. It is a unique instrument in the neutron scattering landscape of North America, and its capabilities are at least equal to similar instruments in the world.
A uniaxial load frame for in situ neutron studies of stress-induced changes in cementitious materials and related systems
Authors: White Claire E. , Garg Nishant , Olds Daniel , Vocaturo Joseph , Everett S. Michelle , Page Katharine
Published: September 2018

For in situ neutron scattering experiments on cementitious materials, it is of great interest to have access to a robust device which can induce uniaxial load on a given solid sample. Challenges involve selection of materials making up the apparatus that are both weak neutron scatterers and yet adequately strong to induce loads of up to a few kilonewtons on the sample. Here, the design and experimental commissioning of a novel load frame is provided with the intended use as a neutron scattering sample environment enabling time-dependent stress-induced changes to be probed in an engineering material under compression. The frame is a scaled down version of a creep apparatus, which is typically used in the laboratory to measure deformation due to creep in concrete. Components were optimized to enable 22 MPa of compressive stress to be exerted on a 1 cm diameter cement cylinder. To minimize secondary scattering signals from the load frame, careful selection of the metal components was needed. Furthermore, due to the need to maximize the wide angular detector coverage and signal to noise for neutron total scattering measurements, the frame was designed specifically to minimize the size and required number of support posts while matching sample dimensions to the available neutron beam size.
Influence of the Hall-bar geometry on harmonic Hall voltage measurements of spin-orbit torques
Authors: Neumann Lukas , Meinert Markus
Published: September 2018

Harmonic Hall voltage measurements are a wide-spread quantitative technique for the measurement of spin-orbit induced effective fields in heavy-metal/ferromagnet heterostructures. In the vicinity of the voltage pickup lines in the Hall bar, the current is inhomogeneous, which leads to a hitherto not quantified reduction of the effective fields and derived quantities, such as the spin Hall angle or the spin Hall conductivity. Here we present a thorough analysis of the influence of the aspect ratio of the voltage pickup lines to current channel widths on the apparent spin Hall angle. Experiments were performed with Hall bars with a broad range of aspect ratios and a substantial reduction of the apparent spin Hall angle is already seen in Hall crosses with an aspect ratio of 1:1. Our experimental results are confirmed by finite-element simulations of the current flow.
Upgrade of X-ray crystal spectrometer for high temperature measurement using neon-like xenon lines on EAST
Authors: Hu R. J. , Chen J. , Delgado-Aparicio L. F. , Wang Q. P. , Du X. W. , Shen J. , Yang X. S. , Wang F. D. , Fu J. , Li Y. Y. , Bitter M. , Hill K. W. , Pablant N. A. , Lee S. G. , Shi Y. J. , Wan B. N. , Ye M. Y. , Lyu B.
Published: September 2018

A two-crystal X-ray spectrometer system has been implemented in the EAST tokamak to simultaneously diagnose high- and low-temperature plasmas using He- and H-like argon spectra. But for future fusion devices like ITER and Chinese Fusion Engineering Test Reactor (CFETR), argon ions become fully stripped in the core and the intensity of the H-like lines will be significantly at high temperatures (Te > 5 keV). With increasing auxiliary heating power on EAST, the core plasma temperature could also reach 5 keV and higher. In such conditions, the use of a xenon puff becomes an appropriate choice for both ion-temperature and flow-velocity measurements. A new two-crystal system using a quartz 110 crystal (2d = 4.913 Å) to view He-like argon lines and a quartz 011 crystal (2d = 6.686 Å) to view Ne-like xenon spectra has been deployed on a poloidal X-ray crystal spectrometer. While the He-like argon spectra will be used to measure the plasma temperature in the edge plasma region, the Ne-like xenon spectra will be used for measurement in the hot core. The new crystal arrangement allows a wide temperature measurement ranging from 0.5 to 10 keV or even higher, being the first tests for burning plasmas like ITER and CFETR. The preliminary result of lab-tests, Ne-like xenon lines measurement will be presented.
Development of a tracer-containing compact-toroid injection system
Authors: Kobayashi D. , Asai T. , Yamada S. , Ishikawa Y. , Tamura N. , Narushima Y.
Published: September 2018

The accumulation and behavior of impurities is one of the most important subjects in the development of magnetically confined fusion reactors because impurities can potentially cause cooling and worsen the confinement of the hot core plasma. Tracer-encapsulated solid pellets (TESPELs) have demonstrated some results for impurity injection for fusion-reactor plasma studies [N. Tamura et al., J. Phys. Conf. Ser. 823, 012003 (2017)]. However, the TESPEL technique has several shortcomings, for example, the penetration depth and the amounts of tracer impurities. In the present study, we have developed a tracer-containing, compact-toroid (TCCT) injection system that utilizes a magnetized coaxial plasma gun (MCPG). The discharge current through the MCPG sputters and ionizes the electrode material, and the Lorenz self-force accelerates it as a plasmoid. The MCPG easily accelerates a magnetized plasmoid to speeds greater than the ion thermal velocity of several tens of kilometers per second. The accelerated and ejected plasmoid that contains the tracer ions is itself a warm, ionized plasma. Therefore, a TCCT can potentially be injected into the core region of a target plasma with less adverse effect.
Uncertainty quantification confirms unreliable extrapolation toward high pressures for united-atom Mie λ-6 force field
Authors: Messerly Richard A. , Shirts Michael R. , Kazakov Andrei F.
Published: September 2018

Molecular simulation results at extreme temperatures and pressures can supplement experimental data when developing fundamental equations of state. Since most force fields are optimized to agree with vapor-liquid equilibria (VLE) properties, however, the reliability of the molecular simulation results depends on the validity/transferability of the force field at higher temperatures and pressures. As demonstrated in this study, although state-of-the-art united-atom Mie λ-6 potentials for normal and branched alkanes provide accurate estimates for VLE, they tend to over-predict pressures for dense supercritical fluids and compressed liquids. The physical explanation for this observation is that the repulsive barrier is too steep for the “optimal” united-atom Mie λ-6 potential parameterized with VLE properties. Bayesian inference confirms that no feasible combination of non-bonded parameters (ϵ, σ, and λ) is capable of simultaneously predicting saturated vapor pressures, saturated liquid densities, and pressures at high temperatures and densities. This conclusion has both practical and theoretical ramifications, as more realistic non-bonded potentials may be required for accurate extrapolation to high pressures of industrial interest.
Insulin dimer dissociation in aqueous solution: A computational study of free energy landscape and evolving microscopic structure along the reaction pathway
Authors: Banerjee Puja , Mondal Sayantan , Bagchi Biman
Published: September 2018

The dissociation of an insulin dimer to two monomers is an important life process. Although the monomer is the biologically active form of the hormone, it is stored in the β-cells of the pancreas in the hexameric form. The latter, when the need comes, dissociates to dimers and the dimers in turn to monomers to maintain the endogenous delivery of the hormone. In order to understand insulin dimer dissociation at a molecular level, we perform biased molecular dynamics simulations (parallel tempering metadynamics in the well-tempered ensemble) of the dissociation of the insulin dimer in water using two order parameters and an all-atom model of the protein in explicit water. The two order parameters selected (after appropriate studies) are the distance (RMM) between the center of mass of two monomers and the number of contacts (NMM) among the backbone-Cα atoms of the two monomers. We calculated the free energy landscape as a function of these two order parameters and determined the minimum free energy pathway of dissociation. We find that the pathway involves multiple minima and multiple barriers. In the initial stage of dissociation, the distance between the monomers does not change significantly but the NMM decreases rapidly. In the latter stage of separation, the opposite occurs, that is, the distance RMM increases at nearly a constant low value of NMM. The configurations of the two monomeric proteins so formed are found to be a bit different due to the entropic reasons. Water is seen to play a key role in the dissociation process stabilizing the intermediates along the reaction path. Our study reveals interesting molecular details during the dissociation, such as the variation in the structural and relative orientational arrangement of the amino acid residues along the minimum energy path. The conformational changes of monomeric insulin in the stable dimer and in the intermediate states during dimer dissociation have been studied in detail.