bluuebunny/crossref_metadata_2025 huggingface dataset:
Are free trade agreements good for the environment? A panel data analysis
Authors: Nemati Mehdi , Hu Wuyang , Reed Michael
Published: October 2018

This study empirically examines the relationship between free trade agreements (FTAs) and greenhouse gas (GHG) emissions. For this purpose, we use three different FTAs: the Southern Common Market, the North American Free Trade Agreement, and the Australia–United States Free Trade Agreement. These FTAs are between developing, both developing and developed, and only developed countries, respectively. Panel unit root, panel cointegration, and fully modified ordinary least squares estimations are employed to examine the long‐run relationship between GHG emissions and trade liberalization. The results indicate that the environmental effects of FTAs depend on the different agreement types. When FTAs are between only developed or developing countries, overall there is no environmental damage, and these types of FTAs can be beneficial for the environmental quality in the long run. However, when developing and developed countries are in a trade agreement, overall environmental quality decreases due to increased GHG emissions.
Evaluating South African Fiscal and Monetary Policy Trade‐offs Using a Wavelet‐Based Model
Authors: Crowley Patrick M. , Hudgins David
Published: October 2018

The balance between South African fiscal and monetary policy in an open economy context poses some interesting questions for policymakers: questions such as whether more aggressive monetary or fiscal policy will likely deliver better growth prospects in the short and medium run, and what will the consequences be for the real exchange rate and for inflation? This research applies wavelet analysis to post‐apartheid South African quarterly macroeconomic data, and uses the decomposition to simulate a large state‐space linear‐quadratic tracking model. We find that restricted fiscal policy is the best option to realise growth, leading to lower interest rates, lower inflation, real exchange depreciation and improved trade balances compared to restricted monetary policy.
Choctaw as a Window into the Clitic/Agreement Split
Authors: Tyler Matthew
Published: October 2018

The Choctaw verb hosts argument‐referencing morphemes that could plausibly be analyzed as φ‐agreement affixes or argument‐doubling clitics. I argue that (almost) all the morphemes in question are clitics, on the basis of several state‐of‐the‐art tests. The bulk of the argumentation comes from two of the morphemes’ properties in particular: firstly, they participate in clitic‐climbing alternations, and secondly, they are able to license the extrinsic plural markeroklah, an element with the syntactic licensing conditions typical of floating quantifiers. Following much work proposing that clitics have the syntactic status of determiner heads in an A‐movement chain with theirDPassociate, I show that the properties just outlined follow straightforwardly from a clitic analysis, but would not be predicted under a φ‐agreement analysis.
Zircon fission‐track ages from Newfoundland—A proxy for high geothermal gradients and exhumation before opening of the Central Atlantic Ocean
Authors: Willner Arne P. , Thomson Stuart N. , Glodny Johannes , Massonne Hans‐Joachim , Romer Rolf L. , van Staal Cees R. , Zagorevski Alexandre
Published: October 2018

Following Appalachian orogenesis, metamorphic rocks in central Newfoundland were exhumed and reburied under Tournaisian strata. New zircon fission‐track (ZFT) ages of metamorphic rocks below the Tournaisian unconformity yield post‐depositionally reset ages of 212–235 Ma indicating regional fluid‐absent reheating to at least ≥220°C. Post‐Tournaisian sedimentary thicknesses in surrounding basins show that burial alone cannot explain such temperatures, thus requiring that palaeo‐geothermal gradients increased to ≥30–40°C/km before final late Triassic accelerated cooling. We attribute these elevated palaeo‐geothermal gradients to localized thermal blanketing by insulating sediments overlying radiogenic high‐heat‐producing granitoids. Late Triassic rifting and magmatism before break up of Pangaea likely also contributed to elevated heat flow, as well as uplift, triggering late Triassic accelerated cooling and exhumation. Thermochronological ages of 240–200 Ma are seen throughout Atlantic Canada, and record rifting and basaltic magmatism on the conjugate margins of the Central Atlantic Ocean preceding the onset of oceanic spreading at ~190 Ma.
Environmental flow assessment for rivers feeding a coastal wetland complex in the Pacific coast of northwest Mexico
Authors: Hernández‐Guzmán Rafael , Ruiz‐Luna Arturo , Cervantes‐Escobar Aimée
Published: October 2018

Hydrological variability is one of the main drivers for rivers structure, and functionality, making the environmental flow (EF) assessment a key element to understand some ecological processes depending on it. Therefore, we aimed to evaluate the EF regime for the main rivers feeding a coastal wetland complex in northwest Mexico, following the hydrologic methodology officially approved by the Mexican National Water Commission based on daily data series (1975–2014). A mean annual runoff around 11 556 Mm3 was estimated to feed the Marismas Nacionales (MN) wetlands system from the discharge of seven rivers. It is expected that the estimated flows, regarded as necessary for the MN system to function properly as a whole, will change because of regional hydraulic infrastructure plans, threatening the discharge of the San Pedro and Baluarte rivers by reducing the flow significantly with negative effects on the MN wetlands.
Weed interference with no‐till soyabeans influenced by fine‐scale covariation between soil properties and cover crop performance
Authors: Eslami S V , Davis A S
Published: October 2018

Balancing trade‐offs in conservation agriculture between the conflicting impacts of soil disturbance on crop yield and soil quality is complicated by the need for adequate weed management, especially in production systems with low, or no, reliance upon herbicides. Production of soyabeans no‐till planted into a rolled‐crimped cereal rye cover crop is attracting increasing farmer interest. Experimental work on this approach to date has provided inferences at the field scale and above, helping to identify broad recommendation domains for best management practices. For individual growers, however, fine‐scale information may also be helpful for making in‐field adjustments to refine the system. In a three‐year field study in Illinois, USA, we quantified key associations among no‐till soyabean performance in a rolled rye system and decametre‐scale variation in soil characteristics, cover crop performance and weed growth. Subfield variation in soil properties had both direct and indirect effects on soyabean yield. Local soil potassium limitation was linked to reduced rye height, which in turn indirectly reduced soyabean yields through decreased weed suppression by the cover crop. Slow‐draining field areas that were still moist at the time of cover crop termination were associated with lower soyabean stands, directly reducing yields. Although the subfield characteristics influencing soyabean and cover crop performance may vary from farm to farm, this study highlights potential gains to be realised in this production system from a better understanding of how such properties covary at fine spatial scales and taking steps to create an environment conducive to maximising cover crop establishment and growth.
MATHEMATICAL MODELLING AND CONCEPTUAL DESIGN OF NOVEL AUTOMATIC TYRE INFLATING SYSTEM
Authors: Subramonian Sivarao , Umesh K. , Salleh M. S. , Sivakumar D. , Izamshah R. , Ali M. A. M.
Published: October 2018

Pneumatic tyres release 10-15 kPa of air pressure every month requires regular topping up. Vehicles run with improper tyre pressure has been identified as one of the primary factors which leads into major and catastrophic road accidents due to puncture and explosion. The main aim of this research work is to design a pressure chamber for an Automatic Tyre Inflating System (ATIS) to replenish the pressure loss of a pneumatic tyre. In this paper, a model has been developed to mathematically derive the critical amount of required pressurized air for ATIS intermediary chamber design. Finite element analysis was also performed onto the designed chamber considering critical engineering elements to ensure safe operation with the pressure of 8449kPa. ATIS is postulated to automatically replenish adequate amount of pressurised air into the tyre when the tyre pressure drops 10% below the desired pressure. Thus, the air loss from the tyre can be continuously compensated for 12 months to have them running with safe pressure at all time without having human intervention to inflate them.
Experiment-Based Quantitative Analysis of Picosecond Pulse-Induced Morphological Changes in Fused Silica
Authors: Yan Jingwen , Wang Han , Shen Hong
Published: October 2018

Due to its excellent quality, fused silica has been widely used in various industrial applications. The nonlinear absorptive nature of ultrafast laser pulses enables the induction of morphological changes within the bulk transparent materials. In this study, the interior modification of fused silica is induced by a picosecond pulsed laser, and the relationship between processing parameters and the modification geometry is demonstrated. Three different patterns are identified according to the geometric characteristics of the modification. Furthermore, a simple experiment-based model considering the incubation effect is put forward to predict picosecond pulse-induced morphological changes in fused silica.
The Effect of Anisotropy on the Percolation Threshold of Sealing Surfaces
Authors: Yang Zhimeng , Liu Jianhua , Ding Xiaoyu , Zhang Feikai
Published: October 2018

The percolation threshold strongly affects sealing performance. This paper investigates the relationship between the percolation threshold and the rough surface anisotropy, which is represented by the Peklenik number, γ. A series of anisotropic rough surfaces were generated and the conjugate gradient-fast Fourier transform (CG-FFT) method was used to determine the percolation threshold. The percolation threshold was found to be A/A0≈0.484±0.009 (averaged over 45 surfaces) was established for an isotropic rough surface (γ=1). Furthermore, it was also found that the percolation threshold decreased from A/A0≈0.528±0.011 to A/A0≈0.431±0.008 as 1/γ increased from 0.6 to 2. Our results differ from the theoretical result of Persson et al., where A/A0=γ/(1+γ). Comparing our calculated results with the theoretical results established the presence of an intersection value of 1/γ that was related to the effect of elastic deformation on the percolation threshold. When 1/γ was smaller than the intersection value, our calculated results were lower than the theoretical ones; and when 1/γ was greater than the intersection value, our calculated results were higher than the theoretical ones.
Soft Actuating Sit-to-Stand Trainer Seat
Authors: Fraiszudeen A. , Yeow C. H.
Published: October 2018

In this paper, we propose a novel type of soft robot for sit to stand (STS) training, which is made with soft bellow actuators. Analysis with five healthy human subjects revealed that there is a statistically significant decrease in the peak and mean muscle activation signal from three out of the four groups of lower limb muscle for STS transition, namely, tibialis anterior, hamstrings, and quadriceps. The peak muscle activation decreased most drastically on the quadriceps muscle group (0.726 ± 0.467 to 0.269 ± 0.334). As reduced muscle activation signal correlates to less muscular effort required by the users, the results show the effectiveness of the device in partially supporting the STS transition of the subject, which subsequently serves as an STS trainer device.
Heat Transfer and Friction Measurement in Pin-Fin Arrays Under Mist Flow Condition
Authors: Wang Szu-Kai , Liu Yao-Hsien
Published: October 2018

Effects of air/water mist flow on endwall heat transfer in a square channel were experimentally investigated using infrared thermography. The purpose was to study the detailed heat transfer contour variation caused by the generation of the liquid films. The surface was roughened with staggered partial pin-fin arrays to enhance flow mixing and liquid entrainment. Two streamwise spacings (Xp/d = 3 and 6) of the fin array were investigated. The gas Reynolds number ranged from 7900 to 24,000. The calculated droplet deposition velocity was comparable to the literature results and was not substantially affected by the gas Reynolds number or fin spacing. For the pin-fin array, heat transfer was dominated by the water accumulation and liquid film formation, which was dependent on the carrier gas flow rate and fin spacing. Furthermore, thick liquid fragments entrained between the fins substantially enhanced local convective heat transfer coefficients. The average heat transfer enhancement on the finned surfaces using mist flow was four times as high as the air flow. The pressure drop from the mist flow was two times as high as the air flow.
Drillstring Failure—Identification, Modeling, and Experimental
Characterization
Authors: Abdo Jamil , Hassan Edris M. , Boulbrachene Khaled , Kwak Jan C. T.
Published: October 2018

Drilling is one of the costliest and risky activities in oil and gas industry due to complexity of interactions with downhole formation. Under such conditions, the uncertainty of drillstring behavior increases, and hence, it becomes difficult to predict the causes, occurrences, and types of failures. Lateral and torsional vibrations often cause failure of bottom hole assembly (BHA), drillstring failure, drill bit, and wall borehole damages. In this work, a model is presented to determine the impact of lateral and torsional vibrations on a drillstring during the drilling operation. The model aims to mimic real drillstring behavior inside a wellbore with regards to its dynamic movements due to multiple real situations such as eccentricity of collars, drill pipe sections, and stick-slip phenomena occurring due to the interaction of the bit and the drillstring with the well formation. The work aims to develop a basis for determining critical operating speeds and design parameters to provide safe drilling procedures and reduce drillstring fatigue failure. Lagrangian approach is used in this study to attain drillstring lateral and torsional vibration coupling equations. The nonlinear equations are solved numerically to obtain the response of the system. In this work, we also present a brief description of an in-house constructed experimental setup. The setup has the capability to imitate the downhole lateral and torsional vibration modes. Parameters from the experimental investigations are incorporated for validation of the mathematical models and for prediction of the drillstring fatigue life. Such investigations are essential for oil/gas industries as they provide solutions as well as recommendations about operating speed, lateral and torsional amplitudes measurements and corrections, and the conditions for avoiding occurrence of natural frequency(ies) of the system.
A Survey on Static Modeling of Miniaturized Pneumatic Artificial Muscles With New Model and Experimental Results
Authors: Ashwin K. P. , Ghosal A.
Published: October 2018

Pneumatic artificial muscles (PAMs) are linear pneumatic actuators consisting of a flexible bladder with a set of in-extensible fibers woven as a sheath on the outside. Upon application of pressure, the actuators contract or expand based on the angle of winding of the braid. Due to the similarity in properties of the actuators with biological muscles and the advantages thereof, these are increasingly being used in many robotic systems and mechanisms. This necessitates the development of mathematical models describing their mechanics for optimal design as well as for application in control systems. This paper presents a survey on different mathematical models described in the literature for representing the statics of PAM. Since it is observed that the validity of existing static models, based on energy balance methods, is not consistent with changes in parameters when applied to their miniaturized versions of pneumatic artificial muscles (MPAM), a new model has been proposed. The model takes into account material properties of the bladder as well as the end-effects which are prominent for MPAMs. Experiments conducted on fabricated MPAMs, of different diameters and lengths, show that the proposed model predicts the pressure-deformation characteristics of MPAMs with maximum error of less than 7%.
Prediction of Wheel Slipping Limits for Mobile Robots
Authors: Whitman Alan , Clayton Garrett , Ashrafiuon Hashem
Published: October 2018

In this paper, we present a method to accurately predict the wheel speed limits at which mobile robots can operate without significant slipping. The method is based on an asymptotic solution of the nonlinear equations of motion. Using this approach, we can predict wheel slipping limits of both the inside and outside wheel when the robot is in a constant circular motion of any radius. The analytical results are supported by experiments, which show that the inside wheel slipping limits for circular motions of various radii occur very close to the predicted values. The method is then applied to predict wheel speed profiles for general motion without slipping and experimentally verified for a sinusoidal path.
Comparison of Computational Fluid Dynamics Simulations and Experiments for Stratified Air-Water Flows in Pipes
Authors: Chinello Gabriele , Ayati Anis Awal , McGlinchey Don , Ooms Gijsbert , Henkes Ruud
Published: October 2018

Stratified gas–liquid flow is a flow regime typically encountered in multiphase pipelines. The understanding and modeling of this regime is of engineering importance especially for the oil and gas industry. In this work, simulations have been conducted for stratified air–water flow in pipes. We solved the Reynolds-averaged Navier–Stokes (RANS) equations with the volume of fluid (VOF) method. The aim of this work was to evaluate the performance of the k–ω shear stress transport (SST) turbulence model with and without damping of the turbulence at the gas–liquid interface. Simulation results were compared with some of the latest experimental results found in the literature. A comparison between the simulated velocity and kinetic energy profiles and the experimental results obtained with the particle image velocimetry (PIV) technique was conducted. The characteristics of the interfacial waves were also extracted and compared with the experiments. It is shown that a proper damping of the turbulence close to the interface is needed to obtain agreement with the experimental pressure drop and liquid hold-up. In its current form, however, RANS with the k–ω turbulence model is still not able to give an accurate prediction of the velocity profiles and of the interface waves.
Rib Turbulator Effects on Crossflow-Fed Shaped Film Cooling Holes
Authors: Fox Dale W. , Jones Fraser B. , McClintic John W. , Bogard David G. , Dyson Thomas E. , Webster Zachary D.
Published: October 2018

Most studies of turbine airfoil film cooling in laboratory test facilities have used relatively large plenums to feed flow into the coolant holes. However, a more realistic inlet condition for the film cooling holes is a relatively small channel. Previous studies have shown that the film cooling performance is significantly degraded when fed by perpendicular internal crossflow in a smooth channel. In this study, angled rib turbulators were installed in two geometric configurations inside the internal crossflow channel, at 45 deg and 135 deg, to assess the impact on film cooling effectiveness. Film cooling hole inlets were positioned in both prerib and postrib locations to test the effect of hole inlet position on film cooling performance. A test was performed independently varying channel velocity ratio and jet to mainstream velocity ratio. These results were compared to the film cooling performance of previously measured shaped holes fed by a smooth internal channel. The film cooling hole discharge coefficients and channel friction factors were also measured for both rib configurations with varying channel and inlet velocity ratios. Spatially averaged film cooling effectiveness is largely similar to the holes fed by the smooth internal crossflow channel, but hole-to-hole variation due to inlet position was observed.
A Comprehensive Model for the Auto-Ignition Prediction in Spark Ignition Engines Fueled With Mixtures of Gasoline and Methane-Based Fuel
Authors: Pipitone Emiliano , Beccari Stefano
Published: October 2018

The introduction of natural gas (NG) in the road transport market is proceeding through bifuel vehicles, which, endowed of a double-injection system, can run either with gasoline or with NG. A third possibility is the simultaneous combustion of NG and gasoline, called double-fuel (DF) combustion: the addition of methane to gasoline allows to run the engine with stoichiometric air even at full load, without knocking phenomena, increasing engine efficiency of about 26% and cutting pollutant emissions by 90%. The introduction of DF combustion into series production vehicles requires, however, proper engine calibration (i.e., determination of DF injection and spark timing maps), a process which is drastically shortened by the use of computer simulations (with a 0D two zone approach for in-cylinder processes). An original knock onset prediction model is here proposed to be employed in zero-dimensional simulations for knock-safe performances optimization of engines fueled by gasoline-NG mixtures or gasoline-methane mixtures. The model takes into account the negative temperature coefficient (NTC) behavior of fuels and has been calibrated using a considerable amount of knocking in-cylinder pressure cycles acquired on a Cooperative Fuel Research (CFR) engine widely varying compression ratio (CR), inlet temperature, spark advance (SA), and fuel mixture composition, thus giving the model a general validity for the simulation of naturally aspirated or supercharged engines. As a result, the auto-ignition onset is predicted with maximum and mean error of 4.5 and 1.4 crank angle degrees (CAD), respectively, which is a negligible quantity from an engine control standpoint.
Radial Basis Functions Update of Digital Models on Actual Manufactured Shapes
Authors: Evangelos Biancolini Marco , Cella Ubaldo
Published: October 2018

In the mechanical engineering world, there is a growing interest in being able to create so-called “digital twins” to assess the impact to performance or response. Part of the challenge is to be able to include and assess manufactured geometries as opposed to nominal design intent, particularly for components that are sensitive to small shape variations. In this paper, we show how the update of digital models adopted in computer aided engineering (CAE) can be conducted according to a mesh morphing workflow based on radial basis functions (RBF). The CAE mesh of the nominal design is updated onto the actual one as acquired from surveying a manufactured individual. The concept is demonstrated on a practical application, the wing structure of the RIBES experiment, showing how the new proposed method compares with a traditional one based on the reconstruction of the geometrical model.
Operating Hydrogen Gas Transmission Pipelines at Pressures Above
21 MPa
Authors: Drexler Elizabeth S. , Amaro Robert L. , Slifka Andrew J. , Bradley Peter E. , Lauria Damian S.
Published: October 2018

The economical and efficient transportation of hydrogen gas is necessary for it to become a widespread source of energy. One way to improve the economics is to lower the cost of building hydrogen gas pipelines. The recent modification to the ASME B31.12 Code for Hydrogen Piping and Pipelines begins to lower the cost of building pipelines for hydrogen service by allowing the use of high-strength steel that will provide the same margin of safety with thinner pipe walls. Less steel directly impacts the cost of materials and welding. A means of improving efficiency would be to increase the hydrogen gas pressure to augment the volume of products transmitted through the pipeline. The recent B31.12 code modification characterized dozens of fatigue crack growth test results conducted in hydrogen gas pressurized up to 21 MPa with an upper boundary of fatigue crack growth rate (FCGR), defined as a function where all measured FCGRs fall below this boundary. In this study, different pipe geometries, strengths, and pressures with established design protocols were evaluated to determine if the code would require further modifications should linepipes be designed for higher hydrogen gas pressures, up to 34 MPa. It was shown through a numerical exercise that the code could be minimally modified and safety margins would be adequate for those pressures for steels up to and including API-5 L Grade X70.
A Novel Kinematically Redundant Planar Parallel Robot Manipulator With Full Rotatability
Authors: Baron Nicholas , Philippides Andrew , Rojas Nicolas
Published: October 2018

This paper presents a novel kinematically redundant planar parallel robot manipulator, which has full rotatability. The proposed robot manipulator has an architecture that corresponds to a fundamental truss, meaning that it does not contain internal rigid structures when the actuators are locked. This also implies that its rigidity is not inherited from more general architectures or resulting from the combination of other fundamental structures. The introduced topology is a departure from the standard 3-RPR (or 3-RRR) mechanism on which most kinematically redundant planar parallel robot manipulators are based. The robot manipulator consists of a moving platform that is connected to the base via two RRR legs and connected to a ternary link, which is joined to the base by a passive revolute joint, via two other RRR legs. The resulting robot mechanism is kinematically redundant, being able to avoid the production of singularities and having unlimited rotational capability. The inverse and forward kinematics analyses of this novel robot manipulator are derived using distance-based techniques, and the singularity analysis is performed using a geometric method based on the properties of instantaneous centers of rotation. An example robot mechanism is analyzed numerically and physically tested; and a test trajectory where the end effector completes a full cycle rotation is reported. A link to an online video recording of such a capability, along with the avoidance of singularities and a potential application, is also provided.
An Artificial Bee Colony Algorithm for Solving Hydraulic Shaking Table Acceleration Harmonic Estimation Problem
Authors: Yao Jianjun , Wan Zhenshuai , Fu Yu , Sheng Tang , Yang Ming
Published: October 2018

Hydraulic shaking table is an important device to stimulate vibration environment, which has been widely applied to seismic simulation, aerospace and construction engineering. However, the response from the hydraulic shaking table are not considered sinusoid waveform when corresponds to a sinusoidal acceleration excitation due to the presence of harmonic distortion. This work presents an approach based on the artificial bee colony (ABC) algorithm for the harmonic component estimation in a hydraulic shaking table. The results demonstrate that the proposed method can precisely identify the harmonic component and it has great advantage of convergence as well as real-time performance.
Sound Absorption Characteristic of Glass and Plastic Bottles: Considerations of Their Dependences on Material Properties
Authors: Iwase Teruo , Sugie Satoshi , Kurono Hiroyasu , Abe Masayuki , Okada Yasuaki , Yoshihisa Koichi
Published: October 2018

Great number of bottles made by glass, plastic and metal are used to store beverages, liquid ingredients as water, milk, vinegar and also liqueur. Empty bottles after usage are collected for recycling use and resources. Many of them have narrow open mouth and look like typical shape in kinds of Helmholtz resonator. Authors thought that their reuse for functional building parts with sound absorption would be very valuable from points of view of green building and environmental policies, and authors then measured each resonance frequency and sound absorption coefficient of representative, including light-soft-plastic, bottles, with net capacity from 7 to 2000 ml, by setting on the edge of sound tube with diameter of 100 mm.

Sound resonances with sound absorption coefficient of 0.3–1.0 at frequencies from 100 to 1000 Hz clearly depending on the capacity could be confirmed. It was also found that measured result was well matched to the numerical calculation based on acoustic impedance change at each section area gradually changed in bottle. It is thought that combination use of recycled bottles with independent resonance frequency is more effective than use of new uniform perforated plates for wide space where we need additional sound absorption in certain frequency range.
Analysis of the Impact of Different Types of Vibration Isolation on the Dynamic Loading of Machines and the Surrounding Environment
Authors: Ziaran Stanislav , Chlebo Ondrej , Musil Milos
Published: October 2018

The resulting dynamic loading on machines, the environment and humans generated by vibration and noise is dependent on the vibro-insulating components and the quality of resilient materials used in the mounting of these components. Well-designed vibration isolation of vibrating sources can effectively reduce the transmission of vibro-acoustic energy into supporting and surrounding structures. Based on frequency spectrum, the vibro-isolation efficiency of various vibro-insulating components and their resilient materials is analysed. The solution of this problem is based on theoretical knowledge and methodology of the transmission of vibration-sound waves and measurement of the machines involved. Measurements of vibration at the sources and along the path of transmission, as well as sound measurements, were performed for different vibro-isolators to compare real results with theory. Measured components include; isolation of a recirculation fan in a heating plant, air-conditioning unit, and combustion engine of a passenger vehicle. For the detection of the vibro-acoustic energy the vibration and sound were measured and FFT analysis was applied. Finally, this paper suggests measures which can be taken to reduce undesirable vibro-acoustic energy on machines, the environment and bystanders.
Application of an Experimental Modal Analysis on Composite Pressure Vessels for Monitoring Prestress Conditions
Authors: John Sebastian , Eisermann René , Mair Georg
Published: October 2018

Due to high specific stiffness, fibre reinforced plastics are the dominant material group for the design of mobile pressure vessels. At the Federal Institute for Materials Research and Testing (BAM) aging process of composite pressure vessels is studied to be able to give more accurate lifetime predictions in future. Investigations are based on type III breathing air cylinders consisting of an aluminium tank which is fully wrapped with carbon fibre reinforced plastics. The goal is to detect changes of residual stresses over life time which directly affect fatigue strength. Within this paper an approach is presented to monitor residual stresses via an experimental modal analysis (EMA). First, the influence of changed stress conditions on modal parameters is analysed via a numerical study. Secondly, a test bench for an EMA is set up. To be able to analyse cylinders of different prestress condition, several specimens are prestress modified via high-temperature and high-pressure treatment. During the modification processes, specimens are monitored via optical fibres to control prestress modifications. Through experimental measurements of the modified specimens via EMA changes in prestressing can be detected. Finally, the validity and accuracy of the EMA is evaluated critically by comparing all numerically and experimentally obtained data.
Intensity Perception for Complex Vertical Whole-Body Vibration
Authors: Schwendicke Anna , Cheng Shuyue , Yu Xudong , Altinsoy M. Ercan
Published: October 2018

Whole-body vibrations are an integral part of daily life experience. A thorough understanding of human vibration perception is necessary, e.g., for both the design of multi-modal virtual environments as well as the evaluation of comfort in the automotive industry. In this study, intensity perception for whole-body vibrations near threshold has been measured using amplitude modulated signals as well as narrow band noises. Stevens’ exponents have been calculated showing a significant dependence on frequency between 31.5 Hz and 125 Hz with higher frequencies leading to lower Stevens’ exponents. Amplitude modulation does not have an effect on intensity perception. The use of narrow band noise leads to bigger differences among Stevens’ exponents compared to those of sinusoidal signals. It is concluded that perceptual data from experiments with sinusoidal signals can be used to model the intensity perception of modulated signals, but adjustments have to be made for noisy signals.
Climbing the crustal ladder: Magma storage-depth evolution during a volcanic flare-up
Authors: Gualda Guilherme A. R. , Gravley Darren M. , Connor Michelle , Hollmann Brooke , Pamukcu Ayla S. , Bégué Florence , Ghiorso Mark S. , Deering Chad D.
Published: October 2018

Very large eruptions in the TVZ (New Zealand) reveal rapid magma assembly and eruption and progressive magma shallowing with time.
Microphysiological 3D model of amyotrophic lateral sclerosis (ALS) from human iPS-derived muscle cells and optogenetic motor neurons
Authors: Osaki Tatsuya , Uzel Sebastien G. M. , Kamm Roger D.
Published: October 2018

3D physiological models of neuromuscular junctions could facilitate drug screening and research on pathogenesis of ALS.
ITGBL1 modulates integrin activity to promote cartilage formation and protect against arthritis
Authors: Song Eun Kyung , Jeon Jimin , Jang Dong Gil , Kim Ha Eun , Sim Hyo Jung , Kwon Keun Yeong , Medina-Ruiz Sofia , Jang Hyun-Jun , Lee Ah Reum , Rho Jun Gi , Lee Hyun-Shik , Kim Seok Jung , Park Chan Young , Myung Kyungjae , Kim Wook , Kwon Taejoon , Yang Siyoung , Park Tae Joo
Published: October 2018

ITGBL1 promotes chondrogenesis and protects joint cartilage from osteoarthritis by inhibiting integrin-extracellular matrix interaction.
Long noncoding RNA
lnc-TSI
inhibits renal fibrogenesis by negatively regulating the TGF-β/Smad3 pathway
Authors: Wang Peng , Luo Man-Li , Song Erwei , Zhou Zhanmei , Ma Tongtong , Wang Jun , Jia Nan , Wang Guobao , Nie Sheng , Liu Youhua , Hou FanFan
Published: October 2018

A human long noncoding RNA targeting the TGF-β/Smad pathway reduced fibrogenesis in mouse models of renal fibrosis.
PIEZO2 mediates injury-induced tactile pain in mice and humans
Authors: Szczot Marcin , Liljencrantz Jaquette , Ghitani Nima , Barik Arnab , Lam Ruby , Thompson James H. , Bharucha-Goebel Diana , Saade Dimah , Necaise Aaron , Donkervoort Sandra , Foley A. Reghan , Gordon Taylor , Case Laura , Bushnell M. Catherine , Bönnemann Carsten G. , Chesler Alexander T.
Published: October 2018

The stretch-gated ion channel PIEZO2 is required for inflammation-induced tactile allodynia.
The mechanosensitive ion channel Piezo2 mediates sensitivity to mechanical pain in mice
Authors: Murthy Swetha E. , Loud Meaghan C. , Daou Ihab , Marshall Kara L. , Schwaller Frederick , Kühnemund Johannes , Francisco Allain G. , Keenan William T. , Dubin Adrienne E. , Lewin Gary R. , Patapoutian Ardem
Published: October 2018

Piezo2 ion channels mediate mechanical allodynia in mice.
Efficacy of Antifungal Monotherapies and Combinations against Aspergillus calidoustus
Authors: Glampedakis E. , Coste A. T. , Aruanno M. , Bachmann D. , Delarze E. , Erard V. , Lamoth F.
Published: October 2018

Invasive fungal infections due to
Aspergillus calidoustus
with decreased azole susceptibility are emerging in the setting of azole prophylaxis and are associated with poor outcomes. We assessed the
in vitro
activity of antifungal drugs used alone or in combinations against
A. calidoustus
and found a synergistic effect between voriconazole and terbinafine at concentrations within the therapeutic range.
H
2
S, a Bacterial Defense Mechanism against the Host Immune Response
Authors: Toliver-Kinsky Tracy , Cui Weihua , Törö Gabor , Lee Seung-Jin , Shatalin Konstantin , Nudler Evgeny , Szabo Csaba
Published: October 2018

The biological mediator hydrogen sulfide (H
2
S) is produced by bacteria and has been shown to be cytoprotective against oxidative stress and to increase the sensitivity of various bacteria to a range of antibiotic drugs. Here we evaluated whether bacterial H
2
S provides resistance against the immune response, using two bacterial species that are common sources of nosocomial infections,
Escherichia coli
and
Staphylococcus aureus
.
Granzyme B Is an Essential Mediator in CD8+T Cell Killing ofTheileria parva-Infected Cells
Authors: Yang Jie , Pemberton Alan , Morrison W. Ivan , Connelley Tim
Published: October 2018

There is established evidence that cytotoxic CD8+T cells are important mediators of immunity against the bovine intracellular protozoan parasiteTheileria parva. However, the mechanism by which the specific CD8+T cells kill parasitized cells is not understood.
Disrupted Synthesis of a Di-
N
-acetylated Sugar Perturbs Mature Glycoform Structure and Microheterogeneity in the
O
-Linked Protein Glycosylation System of Neisseria elongata subsp.
glycolytica
Authors: Wang Nelson , Anonsen Jan Haug , Viburiene Raimonda , Lam Joseph S. , Vik Åshild , Koomey Michael
Published: October 2018

The genus
Neisseria
includes three major species of importance to human health and disease (
Neisseria gonorrhoeae
,
Neisseria meningitidis
, and
Neisseria lactamica
) that express broad-spectrum
O
-linked protein glycosylation (Pgl) systems. The potential for related Pgl systems in other species in the genus, however, remains to be determined. Using a strain of
Neisseria elongata
subsp.
glycolytica
, a unique tetrasaccharide glycoform consisting of di-
N
-acetylbacillosamine and glucose as the first two sugars followed by a rare sugar whose mass spectrometric fragmentation profile was most consistent with di-
N
-acetyl hexuronic acid and a
N
-acetylhexosamine at the nonreducing end has been identified. Based on established mechanisms for UDP-di-
N
-acetyl hexuronic acid biosynthesis found in other microbes, we searched for genes encoding related pathway components in the
N. elongata
subsp.
glycolytica
genome. Here, we detail the identification of such genes and the ensuing glycosylation phenotypes engendered by their inactivation. While the findings extend the conservative nature of microbial UDP-di-
N
-acetyl hexuronic acid biosynthesis, mutant glycosylation phenotypes reveal unique, relaxed specificities of the glycosyltransferases and oligosaccharyltransferases to incorporate pathway intermediate UDP-sugars into mature glycoforms.

IMPORTANCE
Broad-spectrum protein glycosylation (Pgl) systems are well recognized in bacteria and archaea. Knowledge of how these systems relate structurally, biochemically, and evolutionarily to one another and to others associated with microbial surface glycoconjugate expression is still incomplete. Here, we detail reverse genetic efforts toward characterization of protein glycosylation mutants of
N. elongata
subsp.
glycolytica
that define the biosynthesis of a conserved but relatively rare UDP-sugar precursor. The results show both a significant degree of intra- and transkingdom conservation in the utilization of UDP-di-
N
-acetyl-glucuronic acid and singular properties related to the relaxed specificities of the
N. elongata
subsp.
glycolytica
system
A New Putative Caulimoviridae Genus Discovered through Air Metagenomics
Authors: Rastrojo Alberto , Núñez Andrés , Moreno Diego A. , Alcamí Antonio
Published: October 2018

Members of the
Caulimoviridae
family are important plant pathogens. These circular double-stranded DNA viruses may integrate into the host genome, although this integration is not required for the viral replication cycle.
PacBio Genome Sequences of Escherichia coli Serotype O157:H7, Diffusely Adherent E. coli, and Salmonella enterica Strains, All Carrying Plasmids with an
mcr-1
Resistance Gene
Authors: Lindsey Rebecca L. , Batra Dhwani , Smith Peyton , Patel Pooja N. , Tagg Kaitlin A. , Garcia-Toledo Lisley , Loparev Vladimir N. , Juieng Phalasy , Sheth Mili , Joung Yoo Jin , Rowe Lori A.
Published: October 2018

We report here Illumina-corrected PacBio whole-genome sequences of an
Escherichia coli
serotype O157:H7 strain (2017C-4109), an
E. coli
serotype O[undetermined]:H2 strain (2017C-4173W12), and a
Salmonella enterica
subsp.
enterica
serovar Enteritidis strain (2017K-0021), all of which carried the
mcr-1
resistance gene on an IncI2 or IncX4 plasmid.
Whole-Genome Sequences of Six Listeria monocytogenes Strains Isolated from Food
Authors: Horlbog Jule Anna , Jang Hyein , Gopinath Gopal , Stephan Roger , Guldimann Claudia
Published: October 2018

Here, we report the whole-genome sequences of six
Listeria monocytogenes
strains isolated from meat and milk products in Switzerland. All of these strains carry premature stop codons or amino acid deletions in
inlA
.
Draft Genome Sequences of the Escherichia coli Reference (ECOR) Collection
Authors: Patel Isha R. , Gangiredla Jayanthi , Mammel Mark K. , Lampel Keith A. , Elkins Christopher A. , Lacher David W.
Published: October 2018

Here, we report the genomes of all 72 isolates belonging to the
Escherichia coli
reference (ECOR) collection. Strains in this collection were isolated from diverse hosts and geographic locations and have been used for more than 30 years to represent the phylogenetic diversity of
E. coli
.
Incidence of tuberculosis and the influence of surveillance strategy on tuberculosis case-finding and all-cause mortality: a cluster randomised trial in Indian neonates vaccinated with BCG
Authors: Jenum Synne , Selvam Sumithra , Jesuraj Nelson , Ritz Christian , Hesseling Anneke C , Cardenas Vicky , Lau Esther , Doherty T Mark , Grewal Harleen M S , Vaz Mario
Published: October 2018

Introduction

Accurate tuberculosis (TB) incidence and optimal surveillance strategies are pertinent to TB vaccine trial design. Infants are a targeted population for new TB vaccines, but data from India, with the highest global burden of TB cases, is limited.

Methods

In a population-based prospective trial conducted between November 2006 and July 2008, BCG-vaccinated neonates in South India were enrolled and cluster-randomised to active or passive surveillance. We assessed the influence of surveillance strategy on TB incidence, case-finding rates and all-cause mortality. Predefined criteria were used to diagnose TB. All deaths were evaluated using a verbal autopsy.

Results

4382 children contributed to 8164 person-years (py) of follow-up (loss to follow-up 6.9%); 749 children were admitted for TB evaluation (active surveillance: 641; passive surveillance: 108). The TB incidence was 159.2/100 000 py and the overall case-finding rate was 3.19 per 100 py (95% CI 0.82 to 18.1). Whereas, the case-finding rate for definite TB was similar using active or passive case finding, the case-finding rate for probable TB was 1.92/100 py (95% CI 0.83 to 3.78) with active surveillance, significantly higher than 0.3/100 py (95% CI 0.01 to 1.39, p=0.02) with passive surveillance. Compared to passive surveillance, children with active surveillance had decreased risk of dying (OR 0.68, 95%CI 0.47 to 0.98) which was mostly attributable to reduction of death from pneumonia/respiratory infections (OR 0.34, 95%CI 0.14 to 0.80).

Conclusion

We provide reliable estimates of TB incidence in South Indian children <2 years of age. Active surveillance increased the case-finding rates for probable TB and was associated with reduced all-cause mortality.
Anti–NMDAR encephalitis complicating pregnancy
Authors: Kalam Sabrina , Baheerathan Aravindhan , McNamara Cillian , Singh-Curry Victoria
Published: October 2018

Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis was first reported in 2005 in four patients with ovarian teratomas; there have been many further cases reported since the antigen for the NMDAR antibody was confirmed in 2007. Patients characteristically have a well-defined set of features, characterised by psychiatric disturbance, seizures and cognitive disturbance, followed by movement disorders, disorders of consciousness and dysautonomia. To date, 14 cases of NMDAR encephalitis have been described in the context of pregnancy. We report a case of NMDAR encephalitis in a 34-year-old woman at 8 weeks’ gestation. She had a turbulent clinical course and was initially admitted to a psychiatric unit. She was successfully treated with first-line immunomodulatory therapies and surgical resection of an ovarian teratoma. Following discharge she delivered a healthy baby and made a complete clinical recovery.
History and significance of the trauma resuscitation flow sheet
Authors: Dunn Julie A , Schroeppel Thomas J , Metzler Michael , Cribari Chris , Corey Katherine , Boyd David R
Published: October 2018

There is little to no written information in the literature regarding the origin of the trauma flow sheet. This vital document allows programs to evaluate initial processes of trauma care. This information populates the trauma registry and is reviewed in nearly every Trauma Process Improvement and Patient Safety conference when discerning the course of patient care. It is so vital, a scribe is assigned to complete this documentation task for all trauma resuscitations, and there are continual process improvement efforts in trauma centers across the nation to ensure complete and accurate data collection. Indeed, it is the single most important document reviewed by the verification committee when evaluating processes of care at site visits. Trauma surgeons often overlook its importance during resuscitation, as recording remains the domain of the trauma scribe. Yet it is the first document scrutinized when the outcome is less than what is expected. The development of the flow sheet is not a result of any consensus statement, expert work group, or mandate, but a result of organic evolution due to the need for relevant and better data. The purpose of this review is to outline the origin, importance, and critical utility of the trauma flow sheet.
Early and late complications of bariatric operation
Authors: Lim Robert , Beekley Alec , Johnson Dirk C , Davis Kimberly A
Published: October 2018

Weight loss surgery is one of the fastest growing segments of the surgical discipline. As with all medical procedures, postoperative complications will occur. Acute care surgeons need to be familiar with the common problems and their management. Although general surgical principles generally apply, diagnoses specific to the various bariatric operations must be considered. There are anatomic considerations which alter management priorities and options for these patients in many instances. These problems present both early or late in the postoperative course. Bariatric operations, in many instances, result in permanent alteration of a patient’s anatomy, which can lead to complications at any time during the course of a patient’s life. Acute care surgeons diagnosing surgical emergencies in postbariatric operation patients must be familiar with the type of surgery performed, as well as the common postbariatric surgical emergencies. In addition, surgeons must not overlook the common causes of an acute surgical abdomen—acute appendicitis, acute diverticulitis, acute pancreatitis, and gallstone disease—for these are still among the most common etiologies of abdominal pathology in these patients.