bluuebunny/crossref_metadata_2025 huggingface dataset:
Development of a foldable personal mobility vehicle with one drive wheel
Authors: Sakata Takanori , Nagai Isaku , Watanabe Keigo
Published: October 2019

As a form of new transportation, cooperation of Personal Mobility Vehicles (PMVs) and a public transportation facility attracts attention from a viewpoint of an environmental load. Various compact PMVs adopting the attitude control technology of an inverted pendulum have been already developed. However, it is reported that attitude control becomes unstable under the influence of road surface irregular and level difference in the vehicle using this attitude control. Thus, a foldable three-wheel style PMV is developed in this research. By folding up, carrying into a public transportation facility called a railroad or a bus becomes easy. Moreover, static stability is sustained to the body by being grounded with a total of three wheels, two of which are used in front part whereas one is used in rear part. This needs no introduction of attitude control, which is to make the attitude stable under the influence of a road surface, so that the risk of a fall of a driver can be reduced. Furthermore, the number of sensors and the number of motors can be reduced by setting not to use attitude control and a drive wheel to one. Thereby, the manufacture cost of the body can be held down. Therefore, it is economical, so that it is thought that general spread is easy. This paper reports the outline and design of hardware to be developed, the running speed control technique, and some running performance experiments to be conducted.
Kinematic Motion Control for Robot Mobile Manipulators as Fire Fighters
Authors: Syam Rafiuddin , Sutresman Onny S. , Fahruddin  , Tonggiroh Adi , Amiruddin  , Radja Abdul Mufti
Published: October 2019

The purpose of this research is to make mobile manipulator robot as firefighting, to derivate kinematical formulation for mobile robot manipulator system, beside that is to make control system of such robot. The design and experiments were conducted in a mobile manipulator study as a firefighter. The result of this unmanned robot unmanned robot design can still carry the appropriate the standard sprinkle of firefighting system. The design of mobile manipulutor mechanism is done by using 3 SolidWorks 2010 design software design. The process of making robot begins with mobile robot as base frame and then installed the robot manipulator. Direct control method was done in this research by using arduino mega as interface system. The conclusion of this research is that robot can move with direct control and autonavigation for tracking trajectory case as firefighting system.
Synthesis and Characterization of Ni-doped ZnO Thin Films Grown by Sol-Gel Spin Coating
Authors: Gareso P.L. , Pakabu Monika , Rauf N. , Juarlin E. , Aryanto Didik
Published: October 2019

ZnO thin film doped with nickel has been grown by sol-gel spin coating technique. The thin films were prepared using zinc acetate dehydrate, ISO propanol, and ethanolamine as a precursor, solvent, and stabilizer respectively. For dopant, Nickel (II) acetate tetrahydrate with different concentration of Ni was added to the mixture. The sol-gel was deposited on a corning glass substrate at room temperature with a speed rate of 3000 rpm during 60 seconds. The Ni-doped ZnO thin films were put into a tube furnace for heat treatment at 500°C for 60 minutes. The characterization of the film was studied using X-ray diffraction (X-RD), and the optical transmittance UV-Vis measurements. The X-RD results show that a good crystallite was clearly observed in a hexagonal wurtzite structure with preferential orientation of (101) plane. The optical UV-Vis measurements show that the transmittance value increased with increasing the concentration of a dopant percentage. The optical band gap of Ni-doped ZnO was in the range of 3.20 – 3.23 eV.
Optimization of rotation speed parameters and number of grinding wheels on the quality and production capacity of chicken feed pellets
Authors: Rasyid Syaharuddin , Muchtar Muas , Susanto Tri Agus
Published: October 2019

This paper presents an experimental design approach for the optimization process parameters for the chicken feed pellets. To achieve this goal, the speed parameters and number of grinding wheels are selected and two levels of this parameter are considered. Design of expert (DOE) of tests was used for experimental design and analysis of results. The chicken feed ingredients mixture is formed into pellets using a grinding wheel pellet machine with a variation of 150, 200 and 250 rpm rotation and variations in the number of grinding wheels 4, 6, and 8 pieces. The highest pellet production capacity (26.2 Kg/hour) occurs at 200 rpm rotating speed and 4 pieces of grinding wheels. The highest engine efficiency (87.6%) occurs at 200 rpm rotating speed and 4 pieces of grinding wheels. The highest pellet durability (91.6%) occurs at 200 rpm rotating speed and 4 pieces of grinding wheels. Optimal machining parameters are recommended to produce a pellet production capacity response of 25.6 Kg/hour, 85.53% efficiency machine, and 91.473% durability pellets are 150-225 rpm rotation speed range and 4-5 pieces grinding wheels.
The true working performance inversion simulation analysis of Jinping level-I arch dam
Authors: Zhang G X , Liu Y , Zhang L , Liu Y Z , Li S H
Published: October 2019

Jinping Level-I Super-high Arch Dam, which is up to 305 m high, ranks the highest among all the arch dams that are built up and under construction in the world. But various technical problems have appeared in the design and construction of the super-high arch dam. Therefore, it is necessary to precisely evaluate and predict the temperature, stress and deformation and address the working performance well during the construction, which is critical for the dam construction quality and safe operation of the dam. By performing a whole-dam whole-process simulation analysis, the paper discusses the true load simulation, the simulation of the transverse joint, adiabatic temperature rising model and efficient technologies to resolve difficulties for the super-high arch dam. The whole-dam whole-process simulation analysis platform – SapTis is used to conduct simulation computation in order to track the true working performance of Jinping Level-I super-high arch dam during its construction. Through analysis of the monitoring data and inversion simulation of the computation parameters, the paper simulates the current working performance of the dam, predicts late-stage response, researches the various problems occurring in the construction to come up with effective solutions. The use of the inversion simulation analysis helps have a whole picture of the true working conditions and performance of the dam during its construction, water impounding and operation and guarantee the dam construction quality and operation safety, while creating a new technology solution for the control of high arc dam construction quality.
Structural design and strength analysis of multi-ring packed flywheel with heavy metal alloy segments
Authors: Jiang L , Zhang W , Wu C W , Zhang L P , Zhang Y X , Liu Z Y
Published: October 2019

Flywheel, as a kinetic energy storage and conversion device, has promising applications due to its high efficiency, no pollution and long lifetime. In particular, with a three-layer structure packed with heavy metal alloy middle layer, a flywheel can achieve both a large rotational inertia and a high energy density. To guarantee structural strength safety of this type of multi-ring packed flywheel operating at high temperature, structural and thermal stress analysis for a flywheel with a tungsten alloy layer sandwiched between two stainless steel layers is carried out using finite element method (FEM). Based on plane stress assumption, flywheel stress characteristic along radius under assembly force, centrifugal force and thermal loading is demonstrated. The results show that, the rise of temperature causes inconsistent thermal expansion between neighbouring layers and results in a large thermal stress. Particularly, a high circumferential tensile stress occurs in the middle layer. It is also found that, the segments of the middle tungsten alloy layer can efficiently relieve the inconsistent thermal expansion and lower the thermal stress. Moreover, the number of segments significantly influences the efficiency of thermal stress releasing and the reserved gap between adjacent segments significantly improves the contact pressure between inner hub and tungsten alloy layer. This work may provide reference for structural design of the multi-ring packed flywheels under thermal loading.
Research on vibration characteristic simulation of the 220 kV gas insulated metal enclosed switchgear equipment
Authors: Wang X P , Jiang X P , Wang Q , Long Y K , Tan J W , Hao J
Published: October 2019

GIS equipment (gas insulated switchgear) is more and more popular in power system, and people often pay more attention to its discharge fault than other mechanical faults. But in the operation of GIS, besides discharge faults, mechanical faults are also a major cause of accidents. Therefore, we should give more research to abnormal mechanical vibration. At the same time, compared with discharge signal, mechanical vibration fault is more difficult to study. In this article, based on the size of real GIS equipment, we first built a three-dimensional model through COMSOL software to study the propagation characteristics of vibration signals. Simply considered, the bus air chamber is two-dimensional axisymmetric. Firstly, the natural vibration frequency of the equipment is calculated by finite element method, and the vibration propagation characteristics of GIS shield cover loose of the GIS equipment are calculated and analyzed. The simulation calculation shows that the longer the shell is, the lower the natural vibration frequency is. Therefore, we should pay more attention to the natural vibration frequency far away from 100 Hz, when designing and manufacturing GIS equipment, so as to avoid serious consequences caused by resonance. Because the basic vibration frequency caused by the loosening of shield cover is twice as high as the power frequency of 50 Hz. Then the 100 Hz simulation source is added to COMSOL model as the vibration source of loosening fault, and the propagation rule and characteristics of vibration fault about GIS are received. After the vibration fault occurs, the loosening vibration signal at the connection between the GIS shell and the basin insulator is the strongest. These conclusions by simulation also conform to objective rules and facts. Meanwhile it can guide us to arrange sensors reasonably and improve the signal-to-noise ratio of vibration detection signals.
Numerical modelling for the simulation of nonlinear ultrasound in liquids with gas bubbles
Authors: Vanhille C , Tejedor Sastre M T
Published: October 2019

Several numerical models have been developed in different configurations to simulate the behaviour of finite-amplitude ultrasound when interacting with tiny gas bubbles in a liquid. Since this interaction is highly nonlinear, specific models must be developed to understand the propagation of the waves in this kind of dispersive media for which their nonlinear and attenuation coefficients, as well as the sound speed, are extremely dependent on the ratio of the driven frequency to the bubble resonance. The bubble volume variation is mathematically modelled in the time domain through a Rayleigh-Plesset equation with terms up to the second order, whereas the time-dependent acoustic field relies on the wave equation in one or several dimensions. Both differential equations are coupled and auxiliary conditions are imposed. The differential systems are solved by the developed numerical models. In this paper we study in a three-dimensional resonator with axial symmetry how new harmonics obtained by nonlinear distortion can be enhanced by taking the nonlinear resonance effect into account, and we show that the generation of new frequency components by nonlinear frequency mixing exists. We also analyse the stable cavitation phenomenon in a three-dimensional focused field with axial symmetry by considering a nonlinear dependence of bubble generation in the liquid and the existence of primary Bjerknes forces.
Particle swarm optimization particle filter denoising algorithm with mutation operator
Authors: Chen H X , Fang L , Fan D L , Huang W J , Zhang G Y , Cao C H , Huang J M , Yang L
Published: October 2019

In this paper, a novel particle filter (NPSO-PF) algorithm is proposed, which is called particle cluster optimization particle filter algorithm with mutation operator, which is used for real-time filtering and noise reduction of nonlinear vibration signals. Because of its introduction of mutation operator, this algorithm has no problem that particle swarm optimization (PSO) algorithm is easy to fall into local optimal value and the calculation accuracy is not high. At the same time, through the mutation operation, the distribution and diversity of particles in the sampling process are improved, and the particle filter (PF) algorithm is solved in which the particles are poor and the utilization rate is not high. The mutation control function makes the particle set optimization process in the early and late stages, and improves the convergence speed of the particle set, which greatly reduces the running time of the whole algorithm. Simulation experiments show that compared with PF algorithm and PSO-PF algorithm, the proposed new particle swarm optimization particle filter (NPSO-PF) algorithm has lower root mean square error, shorter running time, higher signal to noise ratio and more stable filtering performance. It is proved that the algorithm is suitable for real-time filtering and noise reduction processing of nonlinear signals.
Numerical study of the reflected elastic waves using Rayleigh diffraction integral
Authors: Maghlaoui N , Djelouah H , Oudina A , Ourak M , Benmeddour F
Published: October 2019

In this work, the transient ultrasonic waves radiated by a linear phased array transducer in a liquid then reflected at a liquid solid interface is studied. A model based on the Rayleigh integral is used where the reflection at the plane interface is considered by using the reflection coefficients for harmonic plane waves. The transient field is obtained by an inverse Fourier transform of the harmonic field. The obtained results highlight the different components of the ultrasonic field: the direct and edge waves as well as the longitudinal head waves or leaky Rayleigh waves. The temporal representation of these waves has been analyzed and discussed by the rays’ model. Instantaneous cartographies allowed a clear description of all the waves which appear at the liquid-solid interface. The results have been compared to those obtained by using a finite element method.
Study on dynamic characteristics of horizontal suspension in engineering vehicle seat based on rolling vibration isolation principle
Authors: Yan Z H , Zhang X J , Liu G Q , Wang Z Y , Luo Y R
Published: October 2019

The low frequency horizontal vibration of engineering vehicles is a part of multidimensional vibration, which causes driver's occupational disease. Therefore, the design of low frequency horizontal vibration isolation is of great significance. The principle of rolling vibration isolation is applied to seat suspension for low frequency horizontal vibration isolation in this paper. The natural frequency characteristic model of horizontal suspension and the seat-human system dynamics model with horizontal suspension based on the Lagrangian equation are established. The dynamic characteristics of rolling horizontal suspension are studied on account of the established models. Results show that this horizontal suspension can achieve very low natural frequency so as to isolate the low frequency vibration in horizontal direction by the matching design of the rollers and concave dimensions. The vibration isolation characteristics of the front and back seat–human system are improved with the reduction of the rollers’ radius. The vibration isolation characteristic of the front and back seat - human system increases with the increase of the concave surfaces’ radius.
Piezo-actuated device for a bio-structural monitoring application through vibration-based condition and electromechanical impedance measurements
Authors: Barco D R , Tinoco H A , Cardona C I , Peña F M
Published: October 2019

This study presents a numerical and experimental development of a piezo-actuated device used for monitoring the stiffness variations of its support through electromechanical impedance measurements. The piezo-device and its components define a clamped beam system activated dynamically by two piezo-transducers that transmit vibrations to the support (monitoring substrate). An harmonic finite element analysis was carried out to understand the effects of the substrate properties on the dynamics of the piezo-device. Experimental tests corroborated the simulations with the correspondence of modal shapes and frequency response functions (FRFs) when the substrate varies its stiffness. A biomedical application was conducted in a bone specimen with three embedded teeth to monitor the stiffness variations induced by drillings in the bone. Results showed that the bone stiffness monitoring could be possible through the teeth due to that the drillings effect were quantified by electrical impedance signals.
Parameter optimization of centrifugal pump impeller
Authors: Zhang X Z , Wang Y W , Hu J S
Published: October 2019

After the hydraulic calculation of the centrifugal pump, some design parameters of the impeller can be obtained. The axial projection of the impeller can then be drawn by conventional methods, but in the process, the determination of some parameters in the axial projection map ignores whether it is an optimal solution. In this paper, orthogonal test method is used to determine the optimal solution and optimal combination of some design parameters in the axial projection map, to achieve multi-objective optimization, and to optimize the axial projection of the impeller, improve the flow curve of the impeller and improve Work efficiency.
Development and engineering application of high-precision and multi-function simulation system for double reheat ultra-supercritical units
Authors: Cai B L , Wang H C
Published: October 2019

Laiwu ultra-super critical double reheat unit is the highest ultra-super critical double reheat unit, with the highest parameters in China, from the safe and economical to run level put forward higher requirements. Taking ultra-super critical double reheat unit as the research object, a high-precision and multi-functional simulation system for ultra-super critical double reheat unit was developed before the unit was generated, to realize the dynamic analysis of ultra-super critical double reheat unit, control strategy verification and operation technique validation; and conduct operator operation and accident management training. provides technical support for the smooth construction, and safe and stable operation of the ultra-super critical double reheat unit.
Relation between stress intensity factor of circumferential crack and adhesive thickness in bonded round bar
Authors: Oda K , Kasamura Y , Nishi M , Tsutsumi N
Published: October 2019

The fracture of the bonded dissimilar materials generally occurs near the interface or at the interface edge. In this study, the stress intensity factors of the circumferential crack near the interface and the circumferential interface crack are analysed by the crack tip stress method. The relation between the dimensionless stress intensity factor of the circumferential crack and the adhesive thickness is investigated. The dimensionless stress intensity factors are defined by using the singular stress value at the crack tip point in bonded round bar without crack. The dimensionless stress intensity factors based on the singular stress value become constant irrespective of the adhesive thickness. In addition, the dimensionless stress intensity factor of the circumferential crack in bonded round bar is compared with that of the edge crack in bonded plate. Both factors coincide with each other when the geometrical condition and material combinations are the same.
A feather precision measurement method
Authors: Zhao Y P , Zhao J S
Published: October 2019

The methods of measurement of the microscopic and macroscopic morphology of feathers are discussed. A three-dimensional coordinate measuring machine and optical microscope are used together, that is, the macroscopic size of the feather is measured using the detection technology of the three-dimensional coordinate measuring machine, and the optical microscope is then used. The static accuracy error produced by the measurement result is (2.9064-4.0235) um, which is much smaller than the measurement error of 0.5 mm of the millimetre measuring ruler; The microscopic dimensions of the plume of the feather plume are measured by microscopy: the result is accurate to micron level, and the gradated scale is accurate to ± 0.5 mm. This study contributes to basic theoretical research in the fields of feather morphology, fractal analysis, and ecology.
Experimental study on dynamic characteristics of wire-cable vibration isolator
Authors: Wang H X , Chen D D , Ji Y Y
Published: October 2019

This study considers the dynamic experimental characteristics of the wire-cable vibration isolator. Orthogonal design scheme is adopted to reduce the test times. A wire-cable vibration isolator will be experimentally tested in the tension-compression mode to analyze its hysteretic behavior in more detail. Experimental data of restoring force and displacement are obtained through periodic test loading. The shape of hysteresis loops of vibration isolator under different excitation amplitudes, excitation frequencies and number of wire-cable loops have been obtained; the area of each hysteresis loop will be calculated by definite integral. The hysteresis loops under different conditions are studied, the results show that the wire-cable vibration isolator has excellent shock isolation characteristics; the isolator exhibits asymmetric hysteresis loops, which possess a hardening loading overlap in the loading curves. Finally, the key influence parameters of the dynamic characteristics are obtained, which establishes the foundation for designing the high performance wire-cable vibration isolator.
Contact force analysis in a planar mechanism with translational clearance joint considering complex contact modes
Authors: Qian M B , Qin Z , Yan S Z , Zhang L
Published: October 2019

A translational joint model with clearance was established. A contact mode identification method was derived on the basis of the classification of contact modes. The positional relationships were classified into three different contact modes. The identification method was applied to a planar mechanism with translational joint. The influences of clearance size and velocity on dynamic characteristics between them were studied. The mean square error value of contact force can be used to evaluate the influence of the clearance on the dynamic characteristics of the mechanism.
Study on parameter identification of vibration absorption system based on acceleration signal
Authors: Guo T N , Yang T , Gu Y C
Published: October 2019

Based on the analysis and processing of acceleration signals, the time domain least square method and frequency domain analytic method are proposed to identify the parameters of vibration absorption system. The mathematical model of vibration reduction and Simulink simulation system are established, two parameter identification methods are validated by known system parameters and vibration signals; and then, based on the acceleration signal, the influence of signal processing on identification accuracy is analyzed. The two identification methods proposed in this paper can accurately identify the parameters of the vibration absorption system, Finally, the experimental results show that the two identification methods have good engineering applicability and scientific research applicability.
Dynamic modelling and analysis of super-high acceleration macro-micro-macro movement platform
Authors: Zhang L F , Ma B , Wu J , Li H , Li G Q
Published: October 2019

In microelectronics manufacturing industry, to obtain the high-acceleration of Marco-micro movement platform was very crucial and difficult. In this paper, a new macromicro-macro movement platform is described. In addition, by the analysis of its driving principle, nine simplified dynamic models and dynamic equations under different motion conditions are established respectively. In different driving modes (single VCM driving mode, double VCMs reverse driving mode and double VCMs same driving mode, respectively), the displacement and velocity of floating stator, macro system and micro system was calculated, respectively. These results imply that the macro-micro-macro movement platform takes a periodic reciprocating motion and the max displacement and velocity of floating stator, macro system and micro system make different change rules, respectively. It concluded that the floating stator effectively isolating the vibration of macro-micro-macro movement platform.
Research on seismic absorption performance of adjacent structures with additional tuned mass dampers
Authors: Sun Q X
Published: October 2019

In order to investigate the seismic performance of adjacent structures with additional tuned mass dampers, this article takes two adjacent single degree of freedom systems as an example, and takes the transfer rate of displacement response of adjacent structures as performance index, analyses the relationship between damping parameters and structural parameters of adjacent structures with additional tuned mass dampers. The numerical relationship between the structural parameters of adjacent structures with tuned mass dampers, the parameters of tuned mass dampers, and Specific Performance of the adjacent structures in Earthquakes has been find out.The optimum structural parameters are obtained by theoretical deduction. Taking displacement response curve as an index, the reliability of the optimum structural parameters is verified.
Simulation design method of free boundary simulator for high precision spacecraft on orbit
Authors: Liu M H , Cao H , Gao H Y
Published: October 2019

The reproduction of on-orbit free boundary is one of the key technologies for highly accurate ground micro-vibration test of high precision optical spacecraft. This paper focuses on the simulation design method of the free boundary simulator based on finite element method (FEM). The preliminary design is modeled by one-dimensional spring elements, which is effective to optimize the critical design parameters. Then the detailed design model is established to verify the capability of strength, the stability and the modal performance of the free boundary simulator. The actual simulator is manufactured according to the simulation design. And the test of the actual simulator indicates that, the simulation results match well with the experimental results. The development of the free boundary simulator of spacecraft can be instructed effectively by the simulation method in this paper.
How to guarantee the results of investigations with limited statistical information
Authors: Voinov K , Esbulatova A
Published: October 2019

What kind of problems do researchers usually have after investigations connected with different physical processes (e.g., temperature, deterioration, pressure, vibration, and so forth)? In many mathematical papers, textbooks and reference books it is suggested that 340-360 statistical data are needed to obtain the right conclusion by experimentation [1-3]. In these cases, much money (and time, days and even months) will be required. Usually, researchers try to restrict the amount of statistical data to 3, 5, 10 or 30 data points. But in this case, they do not have enough information to determine the trustworthiness of their deductions. Our task is the following: to solve this problem and demonstrate the fact that if there are even only three points of observation, we can still obtain a convincing response/result. It is rather difficult to overestimate the significance of this achievement in practice.
Binding non-signatories to arbitration agreements—who are persons ‘claiming through or under’ a party?
Authors: Priskich Vicky
Published: October 2019

The International Arbitration Acts of the UK, Australia, Singapore, and Hong Kong recognize that third persons who are non-signatories to an arbitration agreement but who are ‘claiming through or under’ a party to the arbitration agreement have the status of a party.1 In the UK and Singapore that status means not only that court proceedings involving such non-signatories may be stayed in favour of arbitration but it also binds them to an award. In Hong Kong that status binds non-signatories to an award. In Australia, that status affects whether court proceedings involving non-signatories are stayed in favour of arbitration. A recent judgment by a majority of Australia’s highest appeal court, the High Court of Australia, in Rinehart v Hancock Prospecting Pty Ltd2 has taken a different approach to that prevailing in England as to the range of persons who are capable of ‘claiming through or under’ a party to the arbitration agreement, thereby significantly expanding the range of disputes involving non-signatories that must be referred to arbitration.3 The issue has not arisen for determination before appellate courts in Singapore or Hong Kong. Rinehart therefore represents an important development in common law jurisdictions, compelling arbitration between a signatory and non-signatory to an arbitration agreement.
The Arteries of the Central Forehead: Implications for Facial Plastic Surgery
Authors: Koziej Mateusz , Polak Jakub , Hołda Jakub , Trybus Marek , Hołda Mateusz , Kluza Piotr , Moskała Artur , Chrapusta Anna , Walocha Jerzy , Woźniak Krzysztof
Published: October 2019

Background

The forehead has substantial importance as an aesthetic unit. The central and supraorbital parts of this area are supplied by the supratrochlear (ST) and supraorbital (SO) arteries as well as the recently defined paracentral (PA) and central arteries.

Objectives

The authors aimed to assess the morphometry of the vessels of the forehead in the context of plastic surgery and minimally invasive cosmetic procedures.

Methods

This research included 40 cadavers directed for forensic autopsy and subjected to postmortem computed tomography angiography. In total, 75 hemifaces were examined for the course and location of arteries relative to the bones and surrounding structures.

Results

The arteries were observed as follows: ST in 97.3%, SO in 89.3%, and PA in 44.0%. The PA can be expected in the 13-mm-wide zone starting 2 mm laterally from the midline. The ST should be expected in the 10-mm-wide area extended laterally from the tenth millimeter from the midline, and the SO should be expected in the slightly wider (11 mm) area extending laterally from the 20th millimeter from the midline. For the proximal main trunks of the ST and SO arteries, we observed no overlap between the zones of occurrence, whereas the zones for the PA and ST main proximal trunks did overlap. No distinctive central artery was observed in the midline region of the forehead, but instead a network of small vessels in the midline region was visible.

Conclusions

The ST is the main and most conservative artery of this region and the PA is the most variable. A unique and detailed anatomical map was created to better understand the vasculature of the forehead area.
Ferritin Light Chain (FTL) competes with long noncoding RNA Linc00467 for miR-133b binding site to regulate chemoresistance and metastasis of colorectal cancer
Authors: Li Zengyao , Liu Jing , Chen Hang , Zhang Ye , Shi Haoze , Huang Longchang , Tao Jianxin , Shen Renhui , Wang Tong
Published: October 2019

Although the colorectal cancer (CRC) mortality rates are decreasing in virtue of CRC screening and improved therapeutic methods, CRC is still a leading cause of cancer deaths. One of the main causes is chemoresistance occurrence in CRC. Understanding of the molecular mechanisms of chemoresistance benefits to CRC diagnosis and treatment. In this study, gene expression was determined by western blot and qRT-PCR. The biological functions of genes in CRC cells were studied by knocking down or overexpressing the gene in CRC cells and then analyzing cell sensitivity to 5-Fu by the MTT assay and the flow cytometry, and analyzing cell migration and invasion by transwell assays. The luciferase reporter assay was used to examine microRNA regulation of target gene expression, and biotin pull-down assay was performed to detect interaction between RNA molecules. This study found that ferritin light chain (FTL) and long intergenic noncoding RNA Linc00467 were both upregulated in CRC tissues and cell lines, and inversely correlated to CRC patient survival. FTL and Linc00467 promoted CRC cells abilities to resistance against 5-fluor-ouracil (5-Fu), migration and invasion. These effects were compromised by miR-133b which targeted both FTL and Linc00467. miR-133b interacted with Linc00467 and miR-133b inhibitor prevented Linc00467 knockdown-induced alternations of FTL expression and biological functions. Both FTL and Linc00467 are oncogenes in CRC. FTL expression upregulated in CRC via Linc00467/ miR-133b axis, and leads to CRC cell resistance against 5-FU treatment and promotes CRC metastasis.

FTL expression upregulated in CRC via Linc00467/miR-133b axis, and leads to CRC cell resistance to 5-FU treatment and promotes CRC metastasis.
Blood Cultures Versus Respiratory Cultures: 2 Different Views of Pneumonia
Authors: Haessler Sarah , Lindenauer Peter K , Zilberberg Marya D , Imrey Peter B , Yu Pei-Chun , Higgins Tom , Deshpande Abhishek , Rothberg Michael B
Published: October 2019

Background

Choice of empiric therapy for pneumonia depends on risk for antimicrobial resistance. Models to predict resistance are derived from blood and respiratory culture results. We compared these results to understand if organisms and resistance patterns differed by site. We also compared characteristics and outcomes of patients with positive cultures by site.

Methods

We studied adult patients discharged from 177 US hospitals from July 2010 through June 2015, with principal diagnoses of pneumonia, or principal diagnoses of respiratory failure, acute respiratory distress syndrome, respiratory arrest, or sepsis with a secondary diagnosis of pneumonia, and who had blood or respiratory cultures performed. Demographics, treatment, microbiologic results, and outcomes were examined.

Results

Among 138 561 hospitalizations of patients with pneumonia who had blood or respiratory cultures obtained at admission, 12 888 (9.3%) yielded positive cultures: 6438 respiratory cultures, 5992 blood cultures, and 458 both respiratory and blood cultures. Forty-two percent had isolates resistant to first-line therapy for community-acquired pneumonia. Isolates from respiratory samples were more often resistant than were isolates from blood (54.2% vs 26.6%; P < .001). Patients with both culture sites positive had higher case-fatality, longer lengths of stay, and higher costs than patients who had only blood or respiratory cultures positive. Among respiratory cultures, the most common pathogens were Staphylococcus aureus (34%) and Pseudomonas aeruginosa (17%), whereas blood cultures most commonly grew Streptococcus pneumoniae (33%), followed by S. aureus (22%).

Conclusions

Patients with positive respiratory tract cultures are clinically different from those with positive blood cultures, and resistance patterns differ by source. Models of antibiotic resistance should account for culture source.
A randomized cross-over study with objective quantification of the performance of an asymmetric triacetate and a polysulfone dialysis membrane using different anticoagulation strategies
Authors: Vanommeslaeghe Floris , Josipovic Iván , Boone Matthieu , Dhondt Annemie , Van Biesen Wim , Eloot Sunny
Published: October 2019

Background

Different strategies can be used to counteract coagulation of extracorporeal systems. Systemic anticoagulation is most widely used in routine clinical practice, but can be contraindicated in specific settings. The Solacea™ dialyser, containing the asymmetric triacetate membrane, claims improved biocompatibility, which should result in decreased tendency for coagulation. We quantified the performance of the Solacea™ versus the FX800CORDIAX dialyser regarding resistance to fibre blocking as assessed by micro-computed tomography (CT).

Methods

This cross-over study with four arms randomized consecutively 10 maintenance haemodialysis patients to a 4-h post-dilution haemodiafiltration session at midweek, using either Solacea™ 19 H or FX800CORDIAX, with either regular or half dose of anticoagulation (EC2017/1459-NCT03820401). Dialyser fibre blocking was visualized in the dialyser outlet potting using a 3D CT scanning technique on micrometre resolution. Extraction ratios of middle molecules [myoglobin, lambda and kappa free light chains (FLCs)] were determined.

Results

The relative number of open fibres post-dialysis was lower in FX800CORDIAX versus Solacea™ dialyser, and this was irrespective of the anticoagulation dose used or the threshold for counting open fibres. Extraction ratios of FLCs were not different at regular anticoagulation between Solacea™ and FX800CORDIAX (21% ± 4% for kappa and 32% ± 8% for lambda with Solacea™ versus 23% ± 7% and 38% ± 6% for FX800CORDIAX), but were superior with the Solacea™ (34% ± 12% versus 22% ± 8% with FX800CORDIAX; P = 0.02) for myoglobin in case of halving anticoagulation dose. No clinically relevant albumin loss was detected.

Conclusions

The Solacea™ dialyser seems to be promising for use in conditions where systemic anticoagulation is contraindicated, as even under conditions of low systemic anticoagulation, virtually no signs of fibre blocking could be observed using the sensitive micro-CT scanning technique. This finding is in line with its presumed good performance in terms of biocompatibility.
A Bayesian Optimization Approach to Compute Nash Equilibrium of Potential Games Using Bandit Feedback
Authors: Aprem Anup , Roberts Stephen
Published: October 2019

Computing a Nash equilibrium for strategic multi-agent systems is challenging for black box systems. Motivated by the ubiquity of games involving exploitation of common resources, this paper considers the above problem for potential games. We use a Bayesian optimization framework to obtain novel algorithms to solve finite (discrete action spaces) and infinite (real interval action spaces) potential games, utilizing the structure of potential games. Numerical results illustrate the efficiency of the approach in computing a Nash equilibrium of static potential games and linear Nash equilibrium of dynamic potential games.
Valvular calcification and risk of peripheral artery disease: the Multi-Ethnic Study of Atherosclerosis (MESA)
Authors: Garg Parveen K , Buzkova Petra , Meyghani Zahra , Budoff Matthew J , Lima Joao , Criqui Michael , Cushman Mary , Allison Matthew
Published: October 2019

Aims

The detection of cardiac valvular calcification on routine imaging may provide an opportunity to identify individuals at increased risk for peripheral artery disease (PAD). We investigated the associations of aortic valvular calcification (AVC) and mitral annular calcification (MAC) with risk of developing clinical PAD or a low ankle–brachial index (ABI).

Methods and results

AVC and MAC were measured on cardiac computed tomography in 6778 Multi-Ethnic Study of Atherosclerosis participants without baseline PAD between 2000 and 2002. Clinical PAD was ascertained through 2015. Incident low ABI, defined as ABI <0.9 and decline of ≥0.15, was assessed among 5762 individuals who had an ABI >0.9 at baseline and at least one follow-up ABI measurement 3–10 years later. Adjusted Cox proportional hazards and Poisson regression modelling were used to determine the association of valvular calcification with clinical PAD and low ABI, respectively. There were 117 clinical PAD and 198 low ABI events that occurred over a median follow-up of 14 years and 9.2 years, respectively. The presence of MAC was associated with an increased risk of clinical PAD [hazard ratio 1.79; 95% confidence interval (CI) 1.04–3.05] but not a low ABI (rate ratio 1.28; 95% CI 0.75–2.19). No significant associations were noted for the presence of AVC and risk of either clinical PAD.

Conclusion

MAC is associated with an increased risk of developing clinical PAD. Future studies are needed to corroborate our findings and better understand whether MAC holds any predictive value as a risk marker for PAD.
A realistic appraisal of the use of embryonic stem cell-based therapies for cardiac repair
Authors: Wysoczynski Marcin , Bolli Roberto
Published: October 2019

Despite the well-documented capacity of embryonic stem cells (ESCs) to differentiate into cardiomyocytes, transplantation of ESCs or ESC-derived cells is plagued by several formidable problems, including graft rejection, arrhythmias, and potential risk of teratomas. Life-long immunosuppression is a disease in itself. Transplantation of human ESC-derived cells in primates causes life-threatening arrhythmias, and the doses used to show efficacy are not clinically relevant. In contemporary clinical research, the margin of tolerance for such catastrophic effects as malignancies is zero, and although the probability of tumours can be reduced by ESC differentiation, it is unlikely to be completely eliminated, particularly when billions of cells are injected. Although ESCs and ESC-derived cells were touted as capable of long-term regeneration, these cells disappear rapidly after transplantation and there is no evidence of long-term engraftment, let alone regeneration. There is, however, mounting evidence that they act via paracrine mechanisms—just like adult cells. To date, no controlled clinical trial of ESC-derived cells in cardiovascular disease has been conducted or even initiated. In contrast, adult cells have been used in thousands of patients with heart disease, with no significant adverse effects and with results that were sufficiently encouraging to warrant Phase II and III trials. Furthermore, induced pluripotent stem cells offer pluripotency similar to ESCs without the need for lifelong immunosuppression. After two decades, the promise that ESC-derived cells would regenerate dead myocardium has not been fulfilled. The most reasonable interpretation of current data is that ESC-based therapies are not likely to have clinical application for heart disease.
Carbo-loading in Coccidioides spp.: a quantitative analysis of CAZyme abundance and resulting glycan populations
Authors: Mitchell Natalie M , Grys Thomas E , Lake Douglas F
Published: October 2019

Coccidioides spp. are important pneumonia-causing pathogens of the American southwest, but little is known about their glycobiology and how their glycosylations differ from other pneumonia-causing fungi. There is mounting preliminary evidence to suggest genus or even species-specific glycosylations in the fungal kingdom due to the presence of unique Carbohydrate-Active Enzymes (CAZymes) in fungal genomes (Deshpande and others 2008; Karkowska-Kuleta and Kozik 2015). If Coccidioides spp.-specific glycans can be identified, it may be possible to exploit these differences to develop more specific diagnostic approaches and more effective therapeutics. Herein we i) mined Coccidioides spp. and other pathogenic fungal genomes to identify CAZymes specific for Coccidiodes spp., ii) proteomically determined the Coccidioides spp. “CAZome” produced in vivo and in vitro, and iii) utilized glycomics to differentiate Coccidioides genus-specific N-glycans from other pathogenic fungi. As far as we are aware, this is the first proteomic and glycomic comparison of the N-glycomes and CAZomes of different fungal genera during infection in human hosts.
The right to freedom of religion and the right against religious discrimination: Theoretical distinctions
Authors: Khaitan Tarunabh , Norton Jane Calderwood
Published: October 2019

This article argues that while they are often conflated, the right to freedom of religion and the right against religious discrimination are in fact distinct human rights. Religious freedom is best understood as protecting our interest in religious adherence (and non-adherence), understood from the committed perspective of the (non)adherent. This internal, committed perspective generates a capacious and realistic conception of religious adherence, which reflects the staggering plurality of forms of religiosity (or lack thereof) as extant in contemporary societies. The right against religious discrimination is best understood as protecting our non-committal interest in the unsaddled membership of our religious group. Thus understood, the two rights have distinct normative rationales. Religious freedom is justified by the need to respect our decisional autonomy in matters of religious adherence. The prohibition on religious discrimination is justified by the need to reduce any significant (political, sociocultural, or material) advantage gaps between different religious groups. These differences reveal a complex map of two overlapping, but conceptually distinct, human rights which are not necessarily breached simultaneously.
On Fingerprinting of Public Malware Analysis Services
Authors: Botas Alvaro , Rodríguez Ricardo J , Matellan Vicente , Garcia Juan F , Trobajo M T , Carriegos Miguel V
Published: October 2019

Automatic public malware analysis services (PMAS, e.g. VirusTotal, Jotti or ClamAV, to name a few) provide controlled, isolated and virtual environments to analyse malicious software (malware) samples. Unfortunately, malware is currently incorporating techniques to recognize execution onto a virtual or sandbox environment; when an analysis environment is detected, malware behaves as a benign application or even shows no activity. In this work, we present an empirical study and characterization of automatic PMAS, considering 26 different services. We also show a set of features that allow to easily fingerprint these services as analysis environments; the lower the unlikeability of these features, the easier for us (and thus for malware) to fingerprint the analysis service they belong to. Finally, we propose a method for these analysis services to counter or at least mitigate our proposal.