bluuebunny/crossref_metadata_2025 huggingface dataset:
Supercritical Carbon Dioxide Extraction of Hevea Brasiliensis Seeds: Influence of Particle Size on to Oil Seed Recovery and its Kinetic
Authors: Yian Lee Nian , Putra Nicky Rahmana , Idham Zuhaili , Mohd Idrus Nor Faadila , Abdul Aziz Ahmad Hazim , Mohd Setapar Siti Hamidah , Che Yunus Mohd Azizi
Published: June 2021

The aim of this study is to investigate the effect of particle sizes on yield, diffusivity, mass transfer and morphological characterization on extraction rate of rubber seed oil recovery by supercritical carbon dioxide (ScCO2). Pressure 30 MPa, temperature 60 oC and average particle size 500 µm gives the maximum oil recovery (34.71%), diffusivity coefficient (5.13 E-12 m2/s) and extraction rate (0.6 mg/sec). The morphological characterization of extracted rubber seeds was done on the basis of scanning electron microscopy which was parallel with the results of the effect of particle size. The results obtained from gas chromatography-mass spectrometry showed that the rubber seeds oil contained significant essential fatty acids and certain chemical constituents which are very valuable.
Recent Progress on CVD Growth of Graphene from a Liquid Carbon Precursor
Authors: Mahyuddin Azzafeerah , Ismail Abd. Khamim , Omar Muhammad Firdaus , Karim Ainul Hakimah
Published: June 2021

Graphene has become a remarkable highlight of advanced material research because of its far superior properties compared to other materials. Chemical vapor deposition (CVD) has emerged as an essential method for scalable production and large area graphene for various applications. Various carbon precursors have been reported for graphene production as they can dramatically impact the graphene growth yield. In the early years of graphene CVD growth, hydrocarbon gases such as methane and acetylene have become favorable carbon precursors because of their stability at elevated temperature and controllable growth. However, hydrocarbon gases are known as explosives and toxic, therefore require a growth system with a high degree of safety and handling precautions. With the limitations mentioned above, liquid carbon source may change the graphene growth landscape as it is relatively inexpensive, non-explosive compared to the conventional gaseous precursor. This article aims to review a detailed synthesis of large-area graphene using liquid carbon precursors via the CVD technique. Challenges and future perspectives are highlights.
Finite Element Analysis of External Fixator for Treating Femur Fracture: Analysis on Stainless Steel and Titanium as Material of External Fixator
Authors: Mohammad Kata Nurnedilah , Zainal Abidin Nur Afikah , Abd Aziz Aishah Umairah , Abdullah Abdul Halim , Wui Ng Bing , Nasution Ahmad Kafrawi , Abdul Kadir Mohammed Rafiq , Ramlee Muhammad Hanif
Published: June 2021

An external fixator device is a medical implant used to keep fractured bones stabilized and in alignment. It consists of pins which are placed into the bone, extending outside the surface of the skin, and attached to a rigid external rod to keep it in place. The aim of this study is to investigate the most suitable material used for the external fixator. Firstly, the 3D model of two unilateral uniplanar external fixator with the properties of titanium and stainless steel were constructed at Solidworks software with all the other parameters set to constant. Meanwhile, CT images of the lower limb were used to reconstruct a 3D model of the femur fracture at Mimics Medical software. Positioning and meshing of both the external fixator and the femur done at 3-Matics Medical and export as Patran for simulation at Marc Mentat software. 375 N load was applied at the most proximal femur to simulate stance phase of a gait cycle. From the findings, external fixator by using stainless steel as material properties have lower maximum von Mises Stress (18.40 MPa) at the femur and (103.69 MPa) at the fixator compared to the titanium (32.38 MPa) at the femur and (182.93 MPa) at the fixator. The result shows a difference of 75% of maximum von Mises Stress at the femur and the external fixator. Configuration by using stainless steel displaced 1.15 mm at the femur and 1.01 mm at the fixator which almost double value of displacement for titanium material for both femur (2.35 mm) and external fixator (2.11 mm). In conclusion, stainless steel external fixators provide better stability when compared to titanium external fixators.
Fabrication, Characterization and Degradation of Electrospun Poly(ε-Caprolactone) Infused with Selenium Nanoparticles
Authors: Kamaruzaman Nurul Asyikin , Mohd Yusoff Abdull Rahim , Nik Malek Nik Ahmad Nizam , Talib Marina
Published: June 2021

Polycaprolactone (PCL) is widely used in the fabrication of nanofibers through electrospinning technique. PCL is a biodegradable material that is economical, simple and can be scaled up for industrial production. In this study, PCL was infused with selenium nanoparticles (SeNPs) via electrospinning to fabricate PCL-SeNPs nanofiber. Field emission scanning electron microscopy (FESEM) images of the samples revealed ‘aligned fibers’ was successfully fabricated with a diameter size of less than 350 nm and an average diameter of 185 nm. The presence of Se in the nanofiber was confirmed by energy dispersive X-ray analysis (EDX) and Raman spectra. Based on the X-ray diffraction (XRD) pattern, the structure of PCL did not change and remains in the PCL-SeNPs nanofibers. The functional groups of PCL, as indicated by infrared (IR) spectra remained the same after SeNPs infusion. These results demonstrated that the physical and chemical properties of PCL nanofibers were not affected by the infusion of SeNPs. In addition, the hydrophobicity of the PCL decreased slightly in the presence of SeNPs. The first month after degradation, disorganized and fibrous fibers of PCL-SeNPs nanofiber were observed followed by the formation of large fiber clumps as degradation time increased. An agglomerated SeNPs made PCL-SeNPs nanofiber pores looser and easier to be hydrolyzed after 4 months of degradation. The sticky surface of PCL-SeNPs nanofiber shows acceleration in the hydrolysis process after 24th weeks of degradation. The presence of SeNPs enhanced the degradation behavior as well as reducing the degradation time to break into pieces, starting after 6 months of degradation. The ‘aligned’ PCL-SeNPs nanofiber, which can mimic the natural tissue extracellular matrix (ECM) morphology, can potentially be used in biomedical applications such as tissue engineering, wound dressing, biomedicine, sensor and filtration application.
Response of Quasi-Integrable and Resonant Hamiltonian Systems to Fractional Gaussian Noise
Authors: Lü Q. F. , Zhu W. Q. , Deng M. L.
Published: June 2021

The major difficulty in studying the response of multi-degrees-of-freedom (MDOF) nonlinear dynamical systems driven by fractional Gaussian noise (fGn) is that the system response is not Markov process diffusion and thus the diffusion process theory cannot be applied. Although the stochastic averaging method (SAM) for quasi Hamiltonian systems driven by fGn has been developed, the response of the averaged systems still needs to be predicted by using Monte Carlo simulation. Later, noticing that fGn has rather flat power spectral density (PSD) in certain frequency band, the SAM for MDOF quasi-integrable and nonresonant Hamiltonian system driven by wideband random process has been applied to investigate the response of quasi-integrable and nonresonant Hamiltonian systems driven by fGn. The analytical solution for the response of an example was obtained and well agrees with Monte Carlo simulation. In the present paper, the SAM for quasi-integrable and resonant Hamiltonian systems is applied to investigate the response of quasi-integrable and resonant Hamiltonian system driven by fGn. Due to the resonance, the theoretical procedure and calculation will be more complicated than the nonresonant case. For an example, some analytical solutions for stationary probability density function (PDF) and stationary statistics are obtained. The Monte Carlo simulation results of original system confirmed the effectiveness of the analytical solutions under certain condition.
Experimental Study of the Sidewall Effect on Three-Dimensional Turbulent Wall Jet
Authors: Kumar Sarvesh , Kumar Amitesh
Published: June 2021

An experimental study on the effect of sidewalls on the flow characteristics of a three-dimensional turbulent square wall jet is carried out at a Reynolds number of 25,000. The sidewalls are defined as the two parallel plates along the vertical jet centerline. Four different sizes of sidewall enclosure (here after referred to as ‘SWE’) are placed at the lateral positions (z) of ±3.5h, ±4h,±4.5h, and ±5h from the vertical jet centerline plane, where h is the height of square jet. The mean characteristics of fluid flow in wall normal (y) and lateral (z) directions at different downstream locations (x/h=0.2−45) are measured using a hotwire anemometer. The velocity measurements are also performed in the z – y lateral plane at four downstream locations (x/h=30, 35, 40,  and  45). Results indicate that the mean velocity profile in lateral and wall normal directions behaves differently depending on the size of SWEs. The decay rate of the maximum mean velocity increases with decrease in size of SWEs after the downstream location (x/h≥20). The decay rate of the maximum mean velocity increases about 5.6% in 140 mm SWE as compared to 200 mm SWE. It is noted that spread of the jet in wall normal and lateral directions increases with decrease in size of SWEs after the attachment of the flow stream on the sidewalls. In the far-field location of the present case, the smaller size of SWE (140 mm SWE) has 10.7% and 23.1% higher spread rate as compared to larger size of SWE (200 mm SWE) in wall-normal and lateral directions, respectively. It is also seen that the self-similar profile gets delayed in wall-normal direction as compared to lateral direction for all the cases. The wall-normal self-similar profile is obtained early with increase in the size of SWEs and it is obtained at x/h=30, 27, 24, and 20 for 140 mm, 160 mm, 180 mm, and 200 mm SWEs, respectively. The flow stream seems to climb the sidewall and this tendency increases with increase in size of SWEs.
A General Outflow Theory Based on Momentum Balance
Authors: Malcherek Andreas
Published: June 2021

One of the oldest problems in the history of hydraulics is the outflow from a vessel through an orifice. In 1644, it was described by the Torricelli principle stating that the outflow velocity is the fall velocity from the filling level. From a theoretical point of view, the Torricelli principle is valid because it follows from Bernoulli's energy conservation principle. In this paper, the outflow problem will be described by Newton's momentum balance principle. Here, the Torricelli formula is obtained when the rounded orifice is treated as a contraction. For the sharp-edged orifice the bulk outflow velocity is the fall velocity from half the filling height. In this momentum balance theory, no artificial outflow coefficients are needed to distinguish between the cases of sharp-edged and rounded orifices.
Effects of Solution Viscosity on Poly(l-Lactic Acid) Porous Microtubes Fabricated by Core–Sheath Electrospinning
Authors: Zhou Yingge , Qavi Imtiaz , Tan George Z.
Published: June 2021

Core–sheath electrospinning is a rapid microfabrication process for creating multilayer polymer microfibers. This paper presents a process based on core–sheath electrospinning to fabricate poly(L-lactic acid) (PLLA) microtubes with nanopores on the tube wall. The morphology of the microtubes mimics human fenestrated capillary vessels. This study investigates the effects of the viscosities of the core and the sheath solutions on the microtube outer diameter and the nanopore size. The core solution shows a dominating influence on the microtube diameter. At the same core solution viscosity level, the microtube diameter is negatively correlated to the core-to-sheath viscosity ratio. The pore size is positively correlated to the microtube diameter. Understanding the effects of solution viscosity on microtube morphology is the prerequisite for process control and microtube product development for future biomedical applications.
Simulations With a Thermodynamically Consistent Model for Convective Transport in Nanofluids
Authors: Bänsch Eberhard , Faghih-Naini Sara
Published: June 2021

A nonhomogeneous model is used to simulate convective transport in nanofluids. The model is a thermodynamically consistent version of the celebrated Buongiorno model. We study two situations in detail: flow through a pipe that is heated periodically in time at one lateral wall and a lid-driven cavity with a triangular heat source placed within. Both studies reveal the mechanisms of enhanced heat transfer by nanofluids through thermophoresis: the temperature gradient at the wall leads to a reduced concentration of nanoparticles. This reduces the concentration-dependent viscosity of the suspension close to the boundary, which in turn leads to a stronger convective transport.
Preliminary Evaluation of Hydraulic Needle Delivery System for Magnetic Resonance Imaging-Guided Prostate Biopsy Procedures
Authors: Mahcicek Davut Ibrahim , Yildirim Korel D. , Kasaci Gokce , Kocaturk Ozgur
Published: June 2021

In clinical routine, the prostate biopsy procedure is performed with the guidance of transrectal ultrasound (TRUS) imaging to diagnose prostate cancer. However, the TRUS-guided prostate biopsy brings reliability concerns due to the lack of contrast difference between prostate tissue and lesions. In this study, a novel hydraulic needle delivery system that is designed for performing magnetic resonance imaging (MRI)-guided prostate biopsy procedure with transperineal approach is introduced. The feasibility of the overall system was evaluated through in vitro phantom experiments under an MRI guidance. The in vitro experiments performed using a certified prostate phantom (incorporating MRI visible lesions). MRI experiments showed that overall hydraulic biopsy needle delivery system has excellent MRI compatibility (signal to noise ratio (SNR) loss < 3%), provides acceptable targeting accuracy (average 2.05±0.46 mm) and procedure time (average 40 min).
Neutronic and Thermal-Mechanical Coupling Schemes for Heat Pipe-Cooled Reactor Designs
Authors: Ma Yugao , Liu Minyun , Xie Biheng , Han Wenbin , Chai Xiaoming , Huang Shanfang , Yu Hongxing
Published: June 2021

Space fission power systems can enable ambitious solar-system and deep-space science missions. The heat pipe-cooled reactor is one of the most potential candidates for near-term space power supply, featuring safety, simplicity, reliability, and modularity. Heat pipe-cooled reactors are solid-state and high-temperature (up to 1500 K) reactors, where the thermal expansion is remarkable and the mechanical response significantly influences the neutronics and thermal analyses. Due to the considerable difference between heat pipe-cooled reactors and traditional water reactors in the structure and design concept, the coupling solutions for light water reactors cannot be directly applied to heat pipe-cooled reactor analyses. Therefore, a new coupling framework and program need to consider the coupling effects among neutronics, heat transfer, and mechanics. Based on the Monte Carlo program rmc and commercial finite element program ansysmechanicalansys parametric design language (APDL), this work introduces the three coupling fields of neutronics (N), thermal (T), and mechanics (M) for heat pipe cooled reactors. Besides, the finite element method and the Monte Carlo program use different meshes and geometry construction methods. Therefore, the spatial mapping and geometry reconstruction are also essential for the N/T-M coupling, which is discussed and established in detail. Furthermore, the N/T-M coupling methods are applied to the preliminary self-designed 10 kWel space heat pipe cooled reactor. Coupling shows that the thermal-mechanical feedback in the solid-state reactor has negative reactivity feedback (about −2000 pcm) while it has a deterioration in heat transfer due to the expansion in the gas gap.
serpent 2 Validation for Radiation Shielding Applications
Authors: Häkkinen Silja
Published: June 2021

This paper contributes to the validation of serpent's photon transport and coupled neutron–photon transport routines. Two benchmarks presenting measurements of neutron and photon flux through different sized iron and lead spheres have been calculated using a development version of serpent and mcnp6.2. The serpent results were compared to the measurement results and the mcnp6.2 calculations. Additionally, the development version has been compared to the currently distributed serpent version 2.1.31. In all cases, the serpent calculated neutron and photon spectra followed the measured spectra fairly well. For the iron spheres, differences between serpent and mcnp6.2 calculated neutron spectra were mostly below 2% at neutron energies below 4 MeV. Differences between photon spectra through the iron spheres were mostly below 3%. For the lead spheres, differences in the calculated neutron spectra were mostly below 1.5% in the energy range 0.04–4.0 MeV. Differences between photon spectra through the 10 cm lead sphere were mostly below 5% and for the larger spheres below 10% except at higher photon energies above 6.5 MeV. Differences between the development version and the serpent version 2.1.31 of the order of 3% were observed in the photon spectra through the largest lead spheres with radius 20 and 30 cm when Gaussian Energy Broadening was not applied. These are probably related to the coupled neutron-photon transport routines in the different versions.
Thermodynamic Investigation on the Performance of Closed Wet Cooling Tower
Authors: Fang Jiamei , Zhao Xuhui , Zhang Lin , Bu Shi , Yu Zhikang , Xu Weigang , Hu Yiyang , Shan Yanfei , Li Yong
Published: June 2021

Closed wet cooling tower (CWCT) is an indirect-contact evaporative cooler, in which ambient air, spray water, and process water function together. In order to improve its thermal performance, a new heat transfer strategy is proposed. The influence of fan frequency, spray density, and processing water flow on the thermal performance of CWCT is obtained by combining theoretical and experimental research. By fitting the experimental data, the empirical formula of heat and mass transfer coefficient is obtained. The research results can be used to improve the cooling efficiency and enhance the heat and mass transfer of CWCT.
Experimental Study of Nanoscale Head-Disk Heat Transfer In Heat-Assisted Magnetic Recording
Authors: Cheng Qilong , Bogy David B.
Published: June 2021

To study the nanoscale heat transfer and laser-related protrusions in heat-assisted magnetic recording (HAMR), we performed static touchdown experiments between HAMR waveguide heads and non-rotating media such as a silicon wafer and a recording disk with an AlMg substrate. During the static touchdown, the laser element is energized with DC current and the embedded contact sensor (ECS) is used to monitor the head temperature. The experimental results show that the thermal fly-height control (TFC) touchdown power decreases with increasing laser current. Meanwhile, the head temperature increases due to the laser heating. From this the ECS resistance rise induced by the laser is extracted. The results show that the silicon wafer dissipates heat effectively under the laser exposure, while the AlMg-substrate disk undergoes a higher temperature rise, which in turn heats the head.
Control of Head Smear Generated From DLC Films Using an External Electric Field
Authors: Tani Hiroshi , Lu Renguo , Koganezawa Shinji , Tagawa Norio
Published: June 2021

In this study, the dependence of the electric field between the magnetic disk and Si wafer, used as the counter surface, on the hydrocarbon smear generated from the diamond-like carbon (DLC) overcoat was investigated. As a result, the positive electric field from the disk to the Si wafer increased the amount of smear, and the negative field reduced it. The positive electric field was estimated to extract hydrocarbon ions from the thermal plasma toward the Si wafer, and the opposite field attracts the hydrocarbon ions to the DLC surface. Therefore, the electric field between the slider and disk possibly controls the smear generation from the DLC overcoat, which is heated by laser irradiation in the heat-assisted magnetic recording).
Electromagnetic Energy Harvester for Transportation Infrastructure Using Vehicle-Tread Force
Authors: Koganezawa Shinji , Morii Kota , Tani Hiroshi , Lu Renguo , Tagawa Norio
Published: June 2021

We propose a novel electromagnetic energy-harvesting device (EHD) for structural health monitoring systems of transportation infrastructures. The EHD is embedded in the road surface and uses the tread force of cars as the input force when tires of cars pass over it. Because the input force is very fast, the proposed EHD can generate a large amount of energy. The footprint of the device is 20 × 20 mm, its height is 7.5 mm, and its volume is 2.4 cm3. We measured the energy generated when a bicycle passed over the EHD 34 times at various speeds between 5 and 15 km/h. Subsequently, we obtained the regression curve from the results, which showed the relationship between the bicycle speed and generated energy, and estimated the electric energy generated by car at higher speeds. The results showed that, even though the size of the EHD was small, electric energies of 100 μJ, and 1.0 mJ could be generated at car speeds of 17 km/h, and 52 km/h, respectively.
Modeling 3D Convolution Architecture for Actions Recognition
Authors: Radulescu Bogdan Alexandru , Radulescu Victorita
Published: June 2021

Action recognition infrastructure can be applied anywhere behavior analysis is required and represents presently a domain of maximum actuality in security and surveillance. The model based on 3D Convolutions is a middle ground between simple key-frame approaches based on 2D convolutions, and other more complex approaches based on Recurrent Neural Networks. Behavior analysis represents a domain greatly improved by action recognition. By placing human actions in different categories it is possible to extract statistics regarding a person’s behavior, characteristics, abilities and preferences which can be processed later by specialized personnel, depending on the selected domain. The proposed model follows simple 3D convolution architecture. Hidden layers are composed of a convolution operation, an activation function and, sometimes, a pooling layer. Leaky ReLU was used as activation function to alleviate the problem of vanishing gradients. Batch Normalization is a technique used for scaling and adjusting the output of an activation layer, and it has been used to reduce over-fitting and decrease the training time. The 3D Convolution structure has the advantage of learning spatio-temporal features, because the convolution is applied over a sequence of frames. In the present paper is presented a proposed 3D convolution model that has average results, with an accuracy of approximately 55% on the NTU RGB+D dataset.
Evaluation of Mechanical Reliability of Micro Bump in Semiconductors Through a Shear Test
Authors: Cho Y. J. , Han M. B. , Bae J. S. , Choi I. J. , Choi D. S. , Noh H. G. , Yoo S. J. , Jang G. H.
Published: June 2021

Micro bump in semiconductor devices is an element to connect silicon dies with through-silicon via to be stacked on each other. The failure of these micro bumps is directly related to the reliability of semiconductors. Of the various mechanical tests, a shear test is commonly used to evaluate mechanical reliability because it provides relatively simple and reliable evaluation data. This paper investigated the failure modes of micro bump due to the structure of micro bumps and tip speed through finite element analysis and shear test. A shear test was conducted for four structures of micro bumps with the radius of 25 μm using a Dage4000+ bond tester under two tip speeds. A finite element model representing the shear test was developed by ANSYS and the analysis was conducted under the same conditions as the experiment. It shows that tungsten via are effective in increasing shear strength of micro bump. Moreover, it also proposes a robust design to increase shear strength of a micro bump.
A New Low Power Photoplethysmography Signal Acquisition System For Mental Stress Estimation
Authors: Pandey Rajeev Kumar , Chao Paul C.-P.
Published: June 2021

This study presents a new low power and robust reflectance type optical Photoplethysmography (PPG) acquisition system for the mental distress estimation. The front-end circuit is implemented in the integrated chip with chip area of 1200μm × 1200μm and fabricated via TSMC T18 process. The sensing range of the readout circuit is 20nA to 11μA, and the total power consumption of the readout system is 100μW. The total power consumption of the design chip including the OLED driver power is 1.64mW. The designed acquisition system is applied to the wrist artery of the two healthy patients when they are calculating the pictorial puzzles and when they are in relax state. The statistical deviation of the heart rate (HR) from the average HR is increased when subjects are in the stress. Also, the standard deviation of pulse rate variability (PRV), the dynamic range of pulse repetition time (PRT), and the standard deviation of PRV derivative show the increasing temporal value when subjects are in the stress.
Mineral Oil As an Alternative Cooling Method
Authors: Estejab Bahareh , Tobin John
Published: June 2021

In an effort to increase the performance ceiling and reduce the size of modern personal computers especially gaming computers and consequently data centers and supercomputers, mineral oil is proposed as the working fluid to cool the system. Mineral oil operates as an avenue for transmission rather than a liquid heatsink for heat storage, which differentiates this project from traditional mineral oil systems. Using non-conductive liquid as cooling fluid brings many advantages due to its higher convective heat transfer coefficient, which leads to more compact computers, higher speed of data transition, more efficient processors, lower noise levels, and less upkeep costs with respect to data centers. Modeling and simulations are done in NX to gauge temperature expectations; which is the most important limitation when designing and testing a computer before construction. The temperature range was found to be 34°C–50°C in the motherboard and 45°C–67°C in the graphic card. Based on the modeling results, a prototype of the proposed computer is built and tested. Ultimately, this project is trying to open up an avenue through which processor design can be reconsidered.
Networking of Digital Twins in the Digital Factory for Single Part Manufacturing Simulation
Authors: Olbort Johannes , Kutscher Vladimir , Moser Maximilian , Anderl Reiner
Published: June 2021

Organizing manufacturing in dynamic networks instead of inflexible production lines is one of the key aspects of Industry 4.0. This should serve to realize automation and effectiveness to a higher degree than previously achievable. For this modernization, Cyber-Physical Systems should be utilized, where a Digital Twin mirrors the behavior of its Physical Twin and makes the data during manufacturing externally available via communication interfaces. This Digital Twin should be an instantiation of a Digital Master, which must meet the requirements for communication in dynamically changing value-added networks. The networking capability of objects requires semantic information. This information is associated with rules for decision making within a value-added network. This paper addresses the need for research on how to add networking capabilities during the development of Digital Masters. With these added capabilities, the communication between Digital Masters and Twins in terms of a single part manufacturing simulation should be verifiable in a Digital Factory. For this purpose, the concept of this paper aims to outline guidelines on how to add networking capabilities to the single part, machines and other resources needed during manufacturing.
Scratch Detection on Hard Disk Drive Media to Reduce Head Disk Interaction and Prevent Data Loss
Authors: Venkatesh Karthik , Srivastava Abhishek , Rai Rahul , Knigge Bernhard
Published: June 2021

Accurately detecting irregularities in the media — thermal asperities and delamination — and mapping them out from further usage is critical to prevent data loss and minimize head disk interaction (HDI). Defect growth is a common concern in hard disk drives (HDD) and the immediate vicinity of media defects are also mapped out to provide sufficient protection against defect growth. A class of media defects that prove more complex to protect against defect growth is scratches on the media. Margining a media scratch involves filling in the gaps between the components of a scratch and margining the vicinity of the scratch in the defect growth direction. While Hough transform based techniques and deeplearning models have been developed to identify media patterns, they cannot be implemented in the hard disk drive firmware due to memory and computational limitations. Here, we present a computationally simple and efficient alternative to identify scratches on the media by combining clustering and an iterative parameter estimation to fit a line to the scratch in noisy conditions. The result is a method that is capable of modeling linear, spiral and parabolic scratches on a media and fill gaps in the scratch and extend the margining at either end of the scratch.
Characterization of Electric Fields Generated by Electricidal Coatings for Biofilm-Resistant Catheters
Authors: Lindgren Luke , Simoes-torigoe Rafaela , Morris Karcher , Talke Frank E.
Published: June 2021

Catheter associated urinary tract infections (CAUTIs) are an endemic problem in the American medical system, causing nearly 32% of all hospital-acquired infections (HAIs) [1]. Novel antimicrobial coatings for catheters, consisting of metal powders (Ag/Ag2O) and polydimethylsiloxane (PDMS), have recently been developed to combat this problem [2,3]. The active ingredients in these coatings were modeled using simplified assumptions in both ANSYS Maxwell and Quantum Espresso to determine the electric field strength at various particle radii. SEM/EDX analysis of the Ag/Ag2O coating was also performed to simulate the particles in ANSYS and provide comparison between idealized models and actual particle geometries.
Development of Algorithms for Performance Index-Based Actuator Fault Detection and Fault-Tolerant Control of Autonomous Vehicle With Adaptive Feedback
Authors: Oh Se-Chan , Oh Kwang-Seok , Lee Jong-Min , Yi Kyong-Su
Published: June 2021

This study proposes algorithms for performance index-based actuator fault detection and fault-tolerant control with adaptive feedback. Longitudinal control algorithm of autonomous vehicles is generally divided into three main parts such as supervisory, upper level, and lower level controllers. In the supervisory controller part, desired behavior is determined based on control targets. Therefore, desired vehicle motion such as longitudinal acceleration can be designed in the upper level controller part using various control methods. In the lower level controller part, actuator control input is determined for tracking the desired vehicle motion designed in the upper level controller part. In order for fault detection and fault-tolerant control of actuators used for longitudinal autonomous driving, adaptive feedback controller has been designed with the MIT rule for determination of the desired longitudinal acceleration and the control input has been compared with the actual acceleration for performance index-based fault detection. It is designed that the adaptive feedback controller adjust the desired acceleration for making reasonable desired behavior despite of existence of actuator fault or performance degradation. The window-based weighted standard deviation of error between the adaptive desired longitudinal acceleration and current acceleration of vehicle has been used for computation of performance index. Performance evaluation has been conducted using Matlab/Simulink and commercial software (CarMaker).
Computational and Experimental Investigation of Contact Detect Response of a Head-Integrated Thermistor on HAMR vs. PMR Media
Authors: Anaya-Dufresne Manuel C. , Li Yixuan , Murthy Peri M. D. , Kiely James , Johnson Michael T. , Bodurtha Kent , Carper Matthew
Published: June 2021

The migration from perpendicular magnetic recording (PMR) to heat-assisted magnetic recording (HAMR) in the hard disc drive (HDD) industry brings unique challenges for head-disc contact detection (CD) and with precisely setting head-disc clearance. In this study we provide numerical model calculations of a head-integrated thermistor’s electric resistance as a function of head-disc clearance and compare the modeled results with measurements of thermistor resistance for heads flying over PMR and HAMR media. Such comparisons serve to assess the accuracy of the modeling techniques and to understand the impact that the media type plays in CD capability of the head-integrated thermistor.
Mn
2+
coordinates Cap-0-RNA to align substrates for efficient 2′-
O
-methyl transfer by SARS-CoV-2 nsp16
Authors: Minasov George , Rosas-Lemus Monica , Shuvalova Ludmilla , Inniss Nicole L. , Brunzelle Joseph S. , Daczkowski Courtney M. , Hoover Paul , Mesecar Andrew D. , Satchell Karla J. F.
Published: June 2021

Efficient RNA capping by the SARS-CoV-2 methyltransferase requires metal ions and a unique four-residue insert.
RAP1 moonlights to activate NF-κB and Notch in ALT
Authors: Churikov Dmitri , Géli Vincent
Published: June 2021

SUMOylated RAP1 dissociates from telomeres to promote their maintenance by ALT (Robinson
et al.
, in 29 June 2021 issue).
Distributing apoptosis protects epithelia
Authors: VanHook Annalisa M.
Published: June 2021

EGFR signaling protects the integrity of epithelia by ensuring that apoptosis events are limited in both space and time.
Subversion of Lipopolysaccharide Signaling in Gingival Keratinocytes via MCPIP-1 Degradation as a Novel Pathogenic Strategy of Inflammophilic Pathobionts
Authors: Gasiorek Anna , Dobosz Ewelina , Potempa Barbara , Ciaston Izabela , Wilamowski Mateusz , Oruba Zuzanna , Lamont Richard J. , Jura Jolanta , Potempa Jan , Koziel Joanna
Published: June 2021

Periodontitis is a highly prevalent disease caused by accumulation of a bacterial biofilm. Periodontal pathogens use a number of virulence strategies that are under intensive study to find optimal therapeutic approaches against bone loss.
DegP Initiates Regulated Processing of Filamentous Hemagglutinin in Bordetella bronchiseptica
Authors: Johnson Richard M. , Nash Zachary M. , Dedloff Margaret R. , Shook John C. , Cotter Peggy A.
Published: June 2021

Two-partner secretion (TPS) systems are broadly distributed among Gram-negative bacteria and play important roles in bacterial pathogenesis. FhaB-FhaC is the prototypical member of the TPS family and we here identified the protease that initiates a processing cascade that controls FhaB function.
Benign myoepithelioma of the soft palate: an unusual clinical entity
Authors: Mireles Marianna Guadalupe , Julián Angelica , Salgado-Chavarría Fabiola , González Guillermo Manuel
Published: June 2021

Myoepitheliomas are rare benign tumours that affect the exocrine glands and are sporadically located in the salivary glands. The most common location of myoepithelioma in the oral cavity is the parotid gland and it is seldom encountered in the palate. The diagnosis of this entity is challenging since its clinical presentation may resemble those of more common neoplasms, rendering a complex histopathological diagnosis. The aim of the present case report is to describe an unusual case of myoepithelioma of the soft palate in a male patient, which developed as an asymptomatic, slowly growing mass. The tumour was assessed with histopathological examination and the diagnosis was verified via immunohistochemistry. Finally, the treatment included surgical resection of the tumour and no signs of recurrence were noted 2.5 years after the surgical procedure. Early diagnosis and treatment plays an important role in the prognosis of this pathological entity.
Role of amyloid β-peptide in the pathogenesis of age-related macular degeneration
Authors: Wang Minwei , Su Shiqi , Jiang Shaoyun , Sun Xinghuai , Wang Jiantao
Published: June 2021

Age-related macular degeneration (AMD) is the most common eye disease in elderly patients, which could lead to irreversible vision loss and blindness. Increasing evidence indicates that amyloid β-peptide (Aβ) might be associated with the pathogenesis of AMD. In this review, we would like to summarise the current findings in this field. The literature search was done from 1995 to Feb, 2021 with following keywords, ‘Amyloid β-peptide and age-related macular degeneration’, ‘Inflammation and age-related macular degeneration’, ‘Angiogenesis and age-related macular degeneration’, ‘Actin cytoskeleton and amyloid β-peptide’, ‘Mitochondrial dysfunction and amyloid β-peptide’, ‘Ribosomal dysregulation and amyloid β-peptide’ using search engines Pubmed, Google Scholar and Web of Science. Aβ congregates in subretinal drusen of patients with AMD and participates in the pathogenesis of AMD through enhancing inflammatory activity, inducing mitochondrial dysfunction, altering ribosomal function, regulating the lysosomal pathway, affecting RNA splicing, modulating angiogenesis and modifying cell structure in AMD. The methods targeting Aβ are shown to inhibit inflammatory signalling pathway and restore the function of retinal pigment epithelium cells and photoreceptor cells in the subretinal region. Targeting Aβ may provide a novel therapeutic strategy for AMD.
Mass drug administration campaigns for scabies and impetigo: protocol for a systematic review and meta-analysis
Authors: Ghosh Pousali , Tesfaye Wubshet , Manandhar Avilasha , Calma Thomas , Bushell Mary , Oguoma Victor M , Kosari Sam , McMillan Faye , Peterson Greg , Thomas Jackson
Published: June 2021

Introduction

Scabies is recognised as a neglected tropical disease, disproportionately affecting the most vulnerable populations around the world. Impetigo often occurs secondarily to scabies. Several studies have explored mass drug administration (MDA) programmes, with some showing positive outcomes—but a systematic evaluation of such studies is yet to be reported. The main aim of this systematic review is to generate comprehensive evidence on the effect and feasibility of MDA programmes in reducing the burden of scabies and impetigo.

Methods and analysis

A systematic review and meta-analysis will be conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis statement. Electronic databases to be searched will include CINAHL EBSCOhost, Medline Ovid, ProQuest, Science Direct, PubMed and SCOPUS. In addition, grey literature will be explored via the Australian Institute of Health and Welfare, Australian Indigenous HealthInfoNet, Informit, OaIster database and WHO. No language restrictions will be applied. All treatment studies following an MDA protocol, including randomised/quasi-controlled trials, and prospective before–after interventional studies, will be considered. The main outcome is the change in prevalence of scabies and impetigo The Cochrane collaboration risk of bias assessment tool will be used for assessing the methodological quality of studies. A random-effect restricted maximum likelihood meta-analysis will be performed to generate pooled effect (OR) using STATA V.16. Appropriate statistical tests will be carried out to quantify heterogeneity between studies and publication bias.

Ethics and dissemination

Ethical approval is not required since data will be extracted from published works. The findings will be communicated to the scientific community through a peer-reviewed journal publication. This systematic review will present an evidence on the effect of MDA interventions on scabies and impetigo, which is instrumental to obtain a clear understanding of the treatments widely used in these programmes.

PROSPERO registration number

CRD42020169544,
Regional anesthesia and acute compartment syndrome: principles for practice
Authors: Dwyer Tim , Burns David , Nauth Aaron , Kawam Kaitlin , Brull Richard
Published: June 2021

Acute compartment syndrome (ACS) is a potentially reversible orthopedic surgical emergency leading to tissue ischemia and ultimately cell death. Diagnosis of ACS can be challenging, as neither clinical symptoms nor signs are sufficiently sensitive. The cardinal symptom associated with ACS is pain reported in excess of what would otherwise be expected for the underlying injury, and not reasonably managed by opioid-based analgesia. Regional anesthesia (RA) techniques are traditionally discouraged in clinical settings where the development of ACS is a concern as sensory and motor nerve blockade may mask symptoms and signs of ACS. This Education article addresses the most common trauma and elective orthopedic surgical procedures in adults with a view towards assessing their respective risk of ACS and offering suggestions regarding the suitability of RA for each type of surgery.
High-dimensional Schwarzschild black holes in scalar–tensor–vector gravity theory
Authors: Cai Xin-Chang , Miao Yan-Gang
Published: June 2021

We obtain a high-dimensional Schwarzschild black hole solution in the scalar–tensor–vector gravity (STVG), and then analyze the influence of parameter $$\alpha $$
α
associated with a deviation of the STVG theory from General Relativity on event horizons and Hawking temperature. We calculate the quasinormal mode frequencies of massless scalar field perturbations for the high-dimensional Schwarzschild STVG black hole by using the sixth-order WKB approximation method and the unstable null geodesic method in the eikonal limit. The results show that the increase of parameter $$\alpha $$
α
makes the scalar waves decay slowly, while the increase of the spacetime dimension makes the scalar waves decay fast. In addition, we study the influence of parameter $$\alpha $$
α
on the shadow radius of this high-dimensional Schwarzschild STVG black hole and find that the increase of parameter $$\alpha $$
α
makes the black hole shadow radius increase, but the increase of the spacetime dimension makes the black hole shadow radius decrease. Finally, we investigate the energy emission rate of the high-dimensional Schwarzschild STVG black hole, and find that the increase of parameter $$\alpha $$
α
makes the evaporation process slow, while the increase of the spacetime dimension makes the process fast.
Magnetoelectric boundary simulated by a Chern–Simons-like model
Authors: Oliveira H. L. , Borges L. H. C. , Barone F. E. , Barone F. A.
Published: June 2021

In this work we study some physical phenomena that emerge in the vicinity of a magnetoelectric boundary. For simplicity, we restrict to the case of a planar boundary described by a coupling between the gauge field with a planar external Chern–Simons-like potential. The results are obtained exactly. We compute the correction undergone by the photon propagator due to the presence of the Chern–Simons coupling and we investigate the interaction between a stationary point-like charge and the magnetoelectric boundary. In the limit of a perfect mirror, where the coupling constant between the field and the potential diverges, we recover the image method. For a non perfect mirror, we show that we have an attenuated image charge and, in addition, an image magnetic monopole whose field strength does not exhibit the presence of the undesirable and artificial divergences introduced by Dirac strings. We also study the interaction between the plate and a quantum particle with spin. In this case we have a kind of charge-magnetic dipole interaction due to the magnetoelectric properties of the plate.
Effects of blood flow characteristics on rupture of cerebral aneurysm: Computational study
Authors: Shen Xiao-Yong , Gerdroodbary M. Barzegar , Poozesh Amin , Musa Abazari Amir , Imani S. Misagh
Published: June 2021

In recent decades, cardiovascular disease and stroke are recognized as the most important reason for the high death rate. Irregular bloodstream and the circulatory system are the main reason for this issue. In this paper, Computational Fluid dynamic method is employed to study the impacts of the flow pattern inside the cerebral aneurysm for detection of the hemorrhage of the aneurysm. To achieve a reliable outcome, blood flow is considered as a non-Newtonian fluid with a power-law model. In this study, the influence of the blood viscosity and velocity on the pressure distribution and average wall shear stress (AWSS) are comprehensively studied. Moreover, the flow pattern inside the aneurysm is investigated to obtain the high-risk regions for the rupture of the aneurysm. Our results indicate that the wall shear stress (WSS) increases with increasing blood flow velocity. Furthermore, the risk of aneurysm rupture is considerably increased when the AWSS increases more than 0.6. Indeed, the blood flow with high viscosity expands the high-risk region on the wall of the aneurysm. Blood flow indicates that the angle of the incoming bloodstream is substantially effective in the high-risk region on the aneurysm wall. The augmentation of the blood velocity and vortices considerably increases the risk of hemorrhage of the aneurysm.
COMPLEXITY AND MEMORY-BASED COMPARISON OF THE BRAIN ACTIVITY BETWEEN ADHD AND HEALTHY SUBJECTS WHILE PLAYING A SERIOUS GAME
Authors: DAWI NORAZRYANA MAT , KUCA KAMIL , KREJCAR ONDREJ , NAMAZI HAMIDREZA
Published: June 2021

Attention deficit hyperactivity disorder (ADHD) is a mental health disorder that is very common among children and may last into their adulthood. It is known that ADHD affects the attention of patients due to problems with short-term memory. Therefore, analysis of attention and memory of these patients should come into consideration. In this study, the complexity and memory of Electroencephalogram (EEG) signals are analyzed to investigate the reduction in attention and memory of patients with ADHD compared to normal subjects while playing a serious game. To achieve this, the fractal dimension and sample entropy of EEG signals are analyzed to evaluate the alterations in the complexity of EEG signals. Moreover, the Hurst exponent of EEG signals for ADHD and non-ADHD subjects is calculated to discuss the memory of EEG signals. The results showed a smaller fractal dimension and sample entropy of EEG signals for patients with ADHD that reflects their lower attention. Besides, the Hurst exponent of EEG signals for these patients reflects their lower memory than normal subjects. Therefore, it can be concluded that the reductions of attention and memory in ADHD subjects are mapped on the reduction of complexity and memory of their EEG signals.
Critical Success Factors for Leveraging Technology Transfer from Higher Education Institutions to Industry: Indian Context
Authors: Kanojia Meenakshi , Shukla Balvinder , Wali Anil , Joshi Manoj
Published: June 2021

This study aims to identify and empirically evaluates the critical factors of successful technology transfer (TT) from higher education institutions (HEI) to industry and to develop a TT model in the Indian context. With the help of questionnaire survey, the perception profile of 318 respondents was collected from PAN-India. Utilizing the survey data, factor analysis identified six constructs representing five critical factors of TT and an outcome factor. The results of multiple regression analysis indicate significant effect of all five critical factors on an outcome factor. The findings of the study validate the TT Model and identify supportive and promotive TT environment factor, market and finance factor and HEI factor to be the most important factors of successful TT. This study may help the policymakers in strategizing future initiatives to improve the rate of successful TT.