bluuebunny/crossref_metadata_2025 huggingface dataset:
Robust Causal Inference with Continuous Instruments Using the Local Instrumental Variable Curve
Authors: Kennedy Edward H. , Lorch Scott , Small Dylan S.
Published: November 2018

Instrumental variables are commonly used to estimate effects of a treatment afflicted by unmeasured confounding, and in practice instruments are often continuous (e.g. measures of distance, or treatment preference). However, available methods for continuous instruments have important limitations: they either require restrictive parametric assumptions for identification, or else rely on modelling both the outcome and the treatment process well (and require modelling effect modification by all adjustment covariates). In this work we develop the first semiparametric doubly robust estimators of the local instrumental variable effect curve, i.e. the effect among those who would take treatment for instrument values above some threshold and not below. In addition to being robust to misspecification of either the instrument or treatment or outcome processes, our approach also incorporates information about the instrument mechanism and allows for flexible data-adaptive estimation of effect modification. We discuss asymptotic properties under weak conditions and use the methods to study infant mortality effects of neonatal intensive care units with high versus low technical capacity, using travel time as an instrument.
Development and implementation of a group based mental health intervention for unaccompanied minors
Authors: Garoff Ferdinand , Kangaslampi Samuli , Peltonen Kirsi
Published: November 2018

Unaccompanied refugee minors (UMs) are at significant risk to experience severe mental health symptoms (Derluyn, Broekaert & Schuyten). Trauma‐focused treatments have been found to be effective for traumatized refugees (Slobodin & de Jong). However, trauma‐focused mental health services are seldom available, and treatment fails when UMs lack trust in service providers (Majumder, O'Reilly, Karim & Vostanis). In order to address this gap, a 10‐session group based mental health intervention for UMs was developed and then pilot tested in 3 accommodation units for UMs in Finland. The implementation and effectiveness of the intervention was studied by qualitative and quantitative methods. The process was completed by 18 UMs. Symptom measures showed no statistically significant changes on the mental health variables studied. However, staff members and UMs reported increased trust and communication, and participating staff members felt empowered to facilitate groups independently. The group model promoted social interaction and built trust in the accommodation units. Further studies are required to UMs.
Spray‐dried plasma deficient in high‐molecular‐weight multimers of von Willebrand factor retains hemostatic properties
Authors: Meledeo Michael Adam , Liu Qiyong Peter , Peltier Grantham C. , Carney Ryan C. , McIntosh Colby S. , Taylor Ashley S. , Bynum James A. , Pusateri Anthony E. , Cap Andrew P.
Published: November 2018

BACKGROUND

Dried plasmas can overcome logistical barriers that prevent fresh frozen plasma (FFP) usage in acute resuscitation, but processing of these products can detrimentally alter the composition. Spray‐dried plasma (SpDP) from single units is deficient in high‐molecular‐weight multimers of von Willebrand factor (vWF), a critical facilitator of platelet adhesion and thrombus formation. We hypothesized that converting high‐molecular‐weight multimers to smaller‐molecular‐weight multimers would retain vWF's capacity to mediate platelet adhesion.

STUDY DESIGN AND METHODS

SpDP obtained from untreated FFP was reconstituted with glycine‐hydrochloric acid (HCl) and glycine (20 mM:50 mM) or pretreated with glycine‐HCl (20 mM) or glycine–glycine‐HCl (20 mM:50 mM) and reconstituted with water. In vitro hemostatic potential of SpDPs versus FFP or FFP spiked with 70 mM of glycine was evaluated, leading to a more detailed in vitro study of glycine‐HCl–glycine (20 mM:50 mM) pretreated SpDP. Plasmas were combined with RBCs and platelets to observe global coagulation response.

RESULTS

While vWF–ristocetin cofactor activity is significantly decreased (−41.13%; p < .0001) in SpDP, a model of vWF‐mediated platelet adhesion to collagen under flow showed enhanced function (+13%; p < .01). Fewer microparticles, particularly of platelet origin, were observed in SpDP versus FFP (p < .0001). Small but significant differences in thromboelastography results were observed, although SpDP and FFP were within normal ranges.

CONCLUSION

Comparable coagulability was observed in FFP and SpDP. The apparent paradox between vWF–ristocetin cofactor assay and vWF‐mediated platelet adhesion may be explained by the increase in smaller multimers of vWF in SpDP, producing different outcomes in these assays.
Statistical Tolerance Analysis of Over-Constrained Mechanical Assemblies With Form Defects Considering Contact Types
Authors: Goka Edoh , Homri Lazhar , Beaurepaire Pierre , Dantan Jean-Yves
Published: November 2018

Tolerance analysis aims toward the verification impact of the individual tolerances on the assembly and functional requirements of a mechanism. The manufactured products have several types of contact and are inherent in imperfections, which often causes the failure of the assembly and its functioning. Tolerances are, therefore, allocated to each part of the mechanism in purpose to obtain an optimal quality of the final product. Three main issues are generally defined to realize the tolerance analysis of a mechanical assembly: the geometrical deviations modeling, the geometrical behavior modeling, and the tolerance analysis techniques. In this paper, a method is proposed to realize the tolerance analysis of an over-constrained mechanical assembly with form defects by considering the contacts nature (fixed, sliding, and floating contacts) in its geometrical behavior modeling. Different optimization methods are used to study the different contact types. The overall statistical tolerance analysis of the over-constrained mechanical assembly is carried out by determining the assembly and the functionality probabilities based on optimization techniques combined with a Monte Carlo simulation (MCS). An application to an over-constrained mechanical assembly is given at the end.
Large Eddy Simulation of Boundary Layer Transition Mechanisms in a Gas-Turbine Compressor Cascade
Authors: Scillitoe Ashley D. , Tucker Paul G. , Adami Paolo
Published: November 2018

Large eddy simulation (LES) is used to explore the boundary layer transition mechanisms in two rectilinear compressor cascades. To reduce numerical dissipation, a novel locally adaptive smoothing (LAS) scheme is added to an unstructured finite volume solver. The performance of a number of subgrid scale (SGS) models is explored. With the first cascade, numerical results at two different freestream turbulence intensities (Ti's), 3.25% and 10%, are compared. At both Ti's, time-averaged skin-friction and pressure coefficient distributions agree well with previous direct numerical simulations (DNS). At Ti = 3.25%, separation-induced transition occurs on the suction surface, while it is bypassed on the pressure surface. The pressure surface transition is dominated by modes originating from the convection of Tollmien–Schlichting waves by Klebanoff streaks. However, they do not resemble a classical bypass transition. Instead, they display characteristics of the “overlap” and “inner” transition modes observed in the previous DNS. At Ti = 10%, classical bypass transition occurs, with Klebanoff streaks incepting turbulent spots. With the second cascade, the influence of unsteady wakes on transition is examined. Wake-amplified Klebanoff streaks were found to instigate turbulent spots, which periodically shorten the suction surface separation bubble. The celerity line corresponding to 70% of the free-stream velocity, which is associated with the convection speed of the amplified Klebanoff streaks, was found to be important.
Vibration-Enhanced Droplet Motion Modes: Simulations of Rocking, Ratcheting, Ratcheting With Breakup, and Ejection
Authors: Huber Ryan A. , Campbell Matthew , Doughramaji Nicole , Derby Melanie M.
Published: November 2018

Power plant water usage is a coupling of the energy–water nexus; this research investigates water droplet motion, with implications for water recovery in cooling towers. Simulations of a 2.6 mm-diameter droplet motion on a hydrophobic, vertical surface were conducted in xflow using the lattice Boltzmann method (LBM). Results were compared to two experimental cases; in the first case, experimental and simulated droplets experienced 30 Hz vibrations (i.e., ±0.1 mm x-direction amplitude, ±0.2 mm y-direction amplitude) and the droplet ratcheted down the surface. In the second case, 100 Hz vibrations (i.e., ±0.8 mm x-direction amplitude, ±0.2 mm y-direction amplitude) caused droplet ejection. Simulations were then conducted for a wide range of frequencies (i.e., 10–100 Hz) and amplitudes (i.e., ±0.018–50 mm), resulting in maximum accelerations of 0.197–1970 m/s2. Under low maximum accelerations (e.g., <7 m/s2), droplets rocked upward and downward in rocking mode, but did not overcome the contact angle hysteresis and, therefore, did not move. As acceleration increased, droplets overcame the contact angle hysteresis and entered ratcheting mode. For vibrations that prompted droplet motion, droplet velocities varied between 10–1000 mm/s. At capillary numbers above approximately 0.0044 and Weber numbers above 3.6, liquid breakup was observed in ratcheting droplets (e.g., the formation of smaller child droplets from the parent droplet). It was noted that both x- and y-direction vibrations were required for droplet ejection.
Analytical Study of Coupling Effects for Vibrations of Cable-Harnessed Beam Structures
Authors: Yerrapragada Karthik , Salehian Armaghan
Published: November 2018

This paper presents a distributed parameter model to study the effects of the harnessing cables on the dynamics of a host structure motivated by space structures applications. The structure is modeled using both Euler–Bernoulli and Timoshenko beam theories (TBT). The presented model studies the effects of coupling between various coordinates of vibrations due to the addition of the cable. The effects of the cable's offset position, pretension, and radius are studied on the natural frequencies of the system. Strain and kinetic energy expressions using linear displacement field assumptions and Green–Lagrange strain tensor are developed. The governing coupled partial differential equations for the cable-harnessed beam that includes the effects of the cable pretension are found using Hamilton's principle. The natural frequencies from the coupled Euler, Bernoulli, Timoshenko and decoupled analytical models are found and compared to the results of the finite element analysis (FEA).
Coarse-Grained Molecular Dynamics Simulation of Fatty Acid Additives in Lubricating Oil Sheared by Corrugated Solid Surfaces
Authors: Zhang Hedong , Washio Sho , Fukuzawa Kenji , Itoh Shintaro
Published: November 2018

A thorough understanding of the dynamic behavior of friction modifier additives added to lubricating oil is crucial for improving the performance of boundary lubrication. However, such understanding is still lacking due to difficulty in measurements. In this study, we used coarse-grained (CG) molecular dynamics (MD) simulations to gain insight into the behavior of stearic acid additives physically adsorbed on corrugated or smooth hematite surfaces which were separated by lubricating oil of dodecane at a nanometric distance and sheared relative to each other. Compared with all-atom MD simulations, our CG MD simulations provided comparable accuracy and 40 times faster computational speed. The simulation results showed that, in contrast to the case of smooth solid surfaces, shear-induced desorption of stearic acid molecules and re-adsorption during rest occurred at the convex portions of the corrugated solid surfaces. This demonstrates that roughness of sliding surfaces largely influences the dynamic behavior of additives in lubricating oil.
A Predictive Approach to the Fault Detection in Fail-Safe System of Autonomous Vehicle Based on the Multi-Sliding Mode Observer
Authors: Oh Kwangseok , Park Sungyoul , Yi Kyongsu
Published: November 2018

This paper describes a predictive method for fault detection in the fail-safe system of autonomous vehicles based on the multi sliding mode observer. In order to detect faults in sensors, such as radar and acceleration sensors used for longitudinal control of the autonomous vehicles, the kinematic model-based sliding mode observer and a predictive algorithm have been used. The driving condition that the subject vehicle is driving with a preceding vehicle has been considered in this study. The relative acceleration has been reconstructed based on the sliding mode observer using relative displacement and velocity. Based on the reconstructed relative acceleration, the upper and lower limits of longitudinal acceleration for fault detection have been derived based on the stochastic analysis of the driver’s driving data. The measured longitudinal acceleration of the subject vehicle has been used to predict the relative states using the longitudinal kinematic model. The predicted relative states have been stored, and the stored states that represent the current states have been used to detect faults in the sensors. With regard to longitudinal acceleration, the multi sliding mode observer has been used to detect faults in the acceleration sensor. The predictive fault detection algorithm proposed in this study can detect faults in the environment sensors individually based on past sensor information. In order to obtain a reasonable performance evaluation, actual driving data and a 3D full vehicle model constructed in the Matlab/Simulink environment have been used in this study. The results of the performance evaluation show that the predictive fault detection algorithm was successfully able to detect faults in the sensors for longitudinal control individually.
An Extended Kalman Filter Based Object Tracking Algorithm for Autonomous Guided Truck Using 1-Layer Laser Scanner
Authors: Oh Kwangseok , Song Taejun , Lee Hyewon
Published: November 2018

This paper describes an extended Kalman filter based object tracking algorithm for autonomous guided truck using 1-layer laser scanner. The 1-layer laser scanner has been used to obtain 2D cloud point data to detect the preceding object for tracking control. The object tracking algorithm proposed in this study consists of perception, decision, and control stages. In the perception stage, object’s information such as relative coordinate and yaw angle has been derived based on coordinate transformation, clustering, and state estimation algorithm using the obtained point data from laser scanner. In order to estimate object’s states such as coordinate and velocity, the extended Kalman filter has been used in this study. Based on the estimated states of the object, the desired path has been derived for calculation of steering angle. The simplified mathematical model of the truck has been derived to design optimal controller. The optimal controller designed in this study is based on the linear quadratic regulator for computing the optimal angle of steering module used for tracking. In order for reasonable performance evaluation, actual data from laser scanner and the derived mathematical model of truck have been used. The developed tracking algorithm and performance evaluation have been designed and conducted on Matlab/Simulink environment. Results of the performance evaluation show that the developed object tracking algorithm has been able to track the preceding object using 1-layer laser scanner.
Antiparasitic Effect of Copper Alloy Surface on
Cryptocaryon irritans
in Aquaculture of
Larimichthys crocea
Authors: Yin Fei , Bao Peibo , Liu Xiao , Yu Youbin , Wang Lei , Wang Lumin
Published: November 2018

Cryptocaryon irritans
, a parasitic ciliate that penetrates the epithelium of the gills, skin, and fins of marine fish, causes acute suffocation and death in cultured fish within days of infection. Much of the existing research centers around the prevention of
C. irritans
infection, but no cure has been found. Studies demonstrate that copper has strong antimicrobial properties, and fish grown in copper-containing cages have lower rates of
C. irritans
infection, compared to those grown in other currently used aquaculture cages. In this study, we found that an alloy containing 74% to 78% copper by weight effectively killed
C. irritans
cells and prevented cryptocaryoniasis outbreaks within a 1-week period. These findings offer a new perspective on the prevention and control of cryptocaryoniasis.
Noninvasive Detection of Equid Herpesviruses in Fecal Samples
Authors: Seeber Peter A. , Dayaram Anisha , Sicks Florian , Osterrieder Nikolaus , Franz Mathias , Greenwood Alex D.
Published: November 2018

Equid herpesviruses (EHVs) establish latent infections, and many EHVs are shed and transmitted via nasal discharge primarily through droplet and aerosol infection. Obtaining nasal swabs and other invasive samples from wildlife is often not possible without capture and physical restraint of individuals, which are resource intensive and a health risk for the captured animals. Fecal EHV shedding has never been demonstrated for naturally infected equids. We established the conditions for fecal EHV screening, and our results suggest that testing fecal samples is an effective noninvasive approach for monitoring acute EHV shedding in equids.
Segmental Variation in a Duplicated
msp2
Pseudogene Generates
Anaplasma marginale
Antigenic Variants
Authors: Graça Telmo , Ku Pei-Shin , Silva Marta G. , Turse Joshua E. , Hammac G. Kenitra , Brown Wendy C. , Palmer Guy H. , Brayton Kelly A.
Published: November 2018

Anaplasma marginale
is a prototypical highly antigenically variant bacterial pathogen dependent on the sequential generation of major surface protein 2 (Msp2) outer membrane variants to establish persistent infection. Msp2 is encoded by a single expression site, and diversity is achieved by gene conversion of chromosomally encoded
msp2
pseudogenes.
Defining the Metabolic Pathways and Host-Derived Carbon Substrates Required for Francisella tularensis Intracellular Growth
Authors: Radlinski Lauren C. , Brunton Jason , Steele Shaun , Taft-Benz Sharon , Kawula Thomas H.
Published: November 2018

The widespread onset of antibiotic resistance prioritizes the need for novel antimicrobial strategies to prevent the spread of disease. With its low infectious dose, broad host range, and high rate of mortality,F. tularensisposes a severe risk to public health and is considered a potential agent for bioterrorism.F. tularensisreaches extreme densities within the host cell cytosol, often replicating 1,000-fold in a single cell within 24 hours. This remarkable rate of growth demonstrates thatF. tularensisis adept at harvesting and utilizing host cell nutrients. However, like most intracellular pathogens, the types of nutrients utilized byF. tularensisand how they are acquired is not fully understood. Identifying the essential pathways forF. tularensisreplication may reveal new therapeutic strategies for targeting this highly infectious pathogen and may provide insight for improved targeting of intracellular pathogens in general.
Silver and Copper Acute Effects on Membrane Proteins and Impact on Photosynthetic and Respiratory Complexes in Bacteria
Authors: Tambosi Reem , Liotenberg Sylviane , Bourbon Marie-Line , Steunou Anne-Soisig , Babot Marion , Durand Anne , Kebaili Nouari , Ouchane Soufian
Published: November 2018

The use of metal ions represents a serious threat to the environment and to all living organisms because of the acute toxicity of these ions. Nowadays, silver nanoparticles are one of the most widely used nanoparticles in various industrial and health applications. The antimicrobial effect of nanoparticles is in part related to the released Ag
+
ions and their ability to interact with bacterial membranes. Here, we identify, both
in vitro
and
in vivo
, specific targets of Ag
+
ions within the membrane of bacteria. This include complexes involved in photosynthesis, but also complexes involved in respiration.
Using Lipoamidase as a Novel Probe To Interrogate the Importance of Lipoylation in Plasmodium falciparum
Authors: Jhun Hugo , Walters Maroya S. , Prigge Sean T.
Published: November 2018

Lipoate is an essential cofactor for a small number of enzymes that are important for central metabolism. Malaria parasites require lipoate scavenged from the human host for growth and survival; however, it is not known why this cofactor is so important. To address this question, we designed a probe of lipoate activity based on the bacterial enzyme lipoamidase (Lpa). Expression of this probe in different subcellular locations allowed us to define the mitochondrion as the compartment housing essential lipoate metabolism. To gain further insight into the specific uses of lipoate in the mitochondrion, we designed a series of catalytically attenuated probes and employed the probes in conjunction with a chemical bypass system. These studies suggest that two lipoylated proteins are required for parasite survival. We were able to express Lpa with different catalytic abilities in different subcellular compartments and driven by different promoters, demonstrating the versatility of this tool and suggesting that it can be used as a probe of lipoate metabolism in other organisms.
Proteomic Dissection of the Cellulolytic Machineries Used by Soil-Dwelling
Bacteroidetes
Authors: Taillefer Marcel , Arntzen Magnus Ø. , Henrissat Bernard , Pope Phillip B. , Larsbrink Johan
Published: November 2018

Cellulose is the most abundant renewable polymer on earth, but its recalcitrance limits highly efficient conversion methods for energy-related and material applications. Though microbial cellulose conversion has been studied for decades, recent advances showcased that large knowledge gaps still exist. Bacteria of the phylum
Bacteroidetes
are regarded as highly efficient carbohydrate metabolizers, but most species are limited to (semi)soluble glycans. A few species, including the soil bacteria
C. hutchinsonii
and
S. myxococcoides
, are regarded as cellulose specialists, but their cellulolytic mechanisms are not understood, as they do not conform to the current models for enzymatic cellulose turnover. By unraveling the proteome setups of these two bacteria during growth on both crystalline cellulose and pectin, we have taken a significant step forward in understanding their idiosyncratic mode of cellulose conversion. This report provides a plethora of new enzyme targets for improved biomass conversion.
Community collective efficacy is associated with reduced physical intimate partner violence (IPV) incidence in the rural province of Mpumalanga, South Africa: findings from HPTN 068
Authors: Leddy Anna M , Lippman Sheri A , Neilands Torsten B , Twine Rhian , Ahern Jennifer , Gómez-Olivé Francesc Xavier , DeLong Stephanie M , MacPhail Catherine , Kahn Kathleen , Pettifor Audrey E
Published: November 2018

Background

Intimate partner violence (IPV) is a human rights violation and is associated with a variety of adverse physical and mental health outcomes. Collective efficacy, defined as mutual trust among community members and willingness to intervene on the behalf of the common good, has been associated with reduced neighbourhood violence. Limited research has explored whether community collective efficacy is associated with reduced incidence of IPV. This is of particular interest among adolescent girls and young women (AGYW) in sub-Saharan Africa, where the burden of HIV is greatest and IPV is common.

Methods

We collected longitudinal data among 2533 AGYW (ages 13–20) enrolled in the HPTN 068 cohort in Mpumalanga province, South Africa between 2011 and 2016. We included participants from 26 villages where community surveys were collected during the HPTN 068 study. Collective efficacy was measured at the village level via two population-based cross-sectional surveys in 2012 and 2014. Multivariable Poisson generalised estimating equation regression models estimated the relative risk ratio (RR) between village collective efficacy scores and subsequent physical IPV 12 month incidence, adjusting for village-level clustering and covariates.

Results

Thirty-eight per cent of the cohort (n=950) reported at least one episode of recent physical IPV during follow-up. For every SD higher level of collective efficacy, there was a 6% lower level of physical IPV incidence (adjusted RR: 0.94; 95% CI 0.89 to 0.98) among AGYW after adjusting for covariates.

Conclusions

Community-level interventions that foster the development of collective efficacy may reduce IPV among AGYW.
Early versus late anticoagulation for ischaemic stroke associated with atrial fibrillation: multicentre cohort study
Authors: Wilson Duncan , Ambler Gareth , Banerjee Gargi , Shakeshaft Clare , Cohen Hannah , Yousry Tarek A , Al-Shahi Salman Rustam , Lip Gregory Y H , Houlden Henry , Brown Martin M , Muir Keith W , Jäger Hans Rolf , Werring David J
Published: November 2018

Background and purpose

The optimal time to start oral anticoagulant (OAC) in patients with ischaemic stroke due to non-valvular atrial fibrillation (AF) is unknown. We reviewed OAC timing in relation to 90-day clinical outcomes as a post hoc analysis from a prospective multicentre observational study.

Methods

We included patients with data on time to initiation of OAC from CROMIS-2 (Clinical Relevence Of Microbleeds In Stroke-2), a prospective observational inception cohort study of 1490 patients with ischaemic stroke or transient ischaemic attack (TIA) and AF treated with OAC. The primary outcome was the composite outcome of TIA, stroke (ischaemic stroke or intracranial haemorrhage) or death within 90 days of the qualifying stroke or TIA. We performed adjusted logistic regression analyses to compare early (0–4 days) and later (≥5 days or never started) OAC initiation.

Results

We included 1355 patients, mean age 76 (SD 10), 580 (43%) women. OAC was started early in 358 (26%) patients and later (or not at all) in 997 (74%) patients. The event rate within 90 days was 48/997 (5%) in the late-OAC group (2 intracranial haemorrhages, 18 ischaemic strokes or TIAs and 31 deaths (three deaths were as a result of new ischaemic strokes)) versus 7/358 (2%) in the early-OAC group (5 ischaemic strokes or TIAs and 2 deaths). In adjusted analyses, late OAC was not associated with the composite outcome (adjusted OR 1.17, 95% CI 0.48 to 2.84, p=0.736).

Conclusion

In adjusted analyses, early OAC after acute ischaemic stroke or TIA associated with AF was not associated with a difference in the rate of the composite outcome of stroke, TIA or death at 90 days, compared with late OAC. However, despite adjustment for important baseline factors, patients selected for early OAC and late OAC might still have differed in important respects; evaluation of OAC timing in adequately powered randomised trials is required.

Clinical trial registration

NCT02513316.
A blind image deblurring algorithm based on relative gradient and sparse representation
Authors: Chen Qiwei , Wang Yiming
Published: November 2018

A blind image deblurring algorithm based on relative gradient and sparse representation is proposed in this paper. The layered method restores the image by three steps: edge extraction, blur kernel estimation and image reconstruction. The positive and negative gradients in texture part have reversal changes, and the edge part that reflects the image structure has only one gradient change. According to the characteristic, the edge of the image is extracted by using the relative gradient of image, so as to estimate the blur kernel of the image. In the stage of image reconstruction, in order to overcome the problem of oversize of the image and the overcomplete dictionary matrix, the image is divided into small blocks. An overcomplete dictionary is used for sparse representation, and the image is reconstructed by the iterative threshold shrinkage method to improve the quality of image restoration. Experimental results show that the proposed method can effectively improve the quality of image restoration.
Control of multi-scroll attractors in a memristor-coupled resonator via time-delayed feedback
Authors: Liu Zhilong , Wu Fuqiang , Alzahrani Faris , Ma Jun
Published: November 2018

A four-variable dynamical system composed of memristor is proposed to investigate the dependence of multi-scroll attractor on initial setting for one variable with memory, and the description for physical background is supplied. It is found that appropriate setting of initial values for the memory variable can induce different numbers of attractor, as a result, resetting initials can change the profile of attractors which is also dependent on the calculating period. Time-delayed feedback is used to stabilize the dynamical system thus the effect of initial dependence is suppressed and multi-scroll attractors are controlled by applying appropriate time delay and feedback gain in the controller. Furthermore, the system is verified on FPGA circuit platform and memristor is used to describe the memory effect of variable related to magnetic flux. It is confirmed that multi-scroll attractors can be stabilized and the dependence of initials setting is suppressed in experiment way.
Computing Complex Horseshoes by Means of Piecewise Maps
Authors: López Álvaro G. , Daza Álvar , Seoane Jesús M. , Sanjuán Miguel A. F.
Published: November 2018

A systematic procedure to numerically compute a horseshoe map is presented. This new method uses piecewise functions and expresses the required operations by means of elementary transformations, such as translations, scalings, projections and rotations. By repeatedly combining such transformations, arbitrarily complex folding structures can be created. We show the potential of these horseshoe piecewise maps to illustrate several central concepts of nonlinear dynamical systems, as for example, the Wada property.
Analysis of Different Management Strategies for Annual Ryegrass (Lolium rigidum) Based on a Population Dynamic Model
Authors: D’Amico María Belén , Calandrini Guillermo L. , González-Andujar José L. , Chantre Guillermo R.
Published: November 2018

Weed species present high competitive capacity, rapid adaptability and herbicide resistance, hindering their effective control across worldwide cropping regions. Since field-conducted experiments are very time-consuming and usually expensive, mathematical population-based models are valuable tools to test and develop long-term weed management programs. Within this context, the objective of this paper is to formalize analytically the possible seed bank dynamics of the Lolium rigidum, subjected to different control strategies. The first focus is on studying in detail the effects of integrating constant actions, promoting more environmentally and economically sustainable scenarios. From the same perspective, an alternative to applying time-variant programs is introduced. The proposed control guarantees that the weed population is sufficiently small or, alternatively, is kept below a given economic threshold level in a ten-year planning horizon. Furthermore, an optimization criterion is adopted for distributing necessary efficiency into diverse integrated options. Numerical simulations are included to illustrate the analytical findings.
Effects of Time Delay on Burst Synchronization Transition of Neuronal Networks
Authors: Sun Xiaojuan , Xue Tianshu
Published: November 2018

In this paper, we focus on investigating the effects of time delay on burst synchronization transitions of a neuronal network which is locally modeled by Hindmarsh–Rose neurons. Here, neurons inside the neuronal network are connected through electrical synapses or chemical synapses. With the numerical results, it is revealed that burst synchronization transitions of both electrically and chemically coupled neuronal networks could be induced by time delay just when the coupling strength is large enough. Meanwhile, it is found that, in electrically and excitatory chemically coupled neuronal networks, burst synchronization transitions are observed through change of spiking number per burst when coupling strength is large enough; while in inhibitory chemically coupled neuronal network, burst synchronization transitions are observed for large enough coupling strength through changing fold-Hopf bursting activity to fold-homoclinic bursting activity and vice versa. Namely, two types of burst synchronization transitions are observed. One type of burst synchronization transitions occurs through change of spiking numbers per burst and the other type of burst synchronization transition occurs through change of bursting types.
Two Simplest Quadratic Chaotic Maps Without Equilibrium
Authors: Panahi Shirin , Sprott Julien C. , Jafari Sajad
Published: November 2018

Two simple chaotic maps without equilibria are proposed in this paper. All nonlinearities are quadratic and the functions of the right-hand side of the equations are continuous. The procedure of their design is explained and their dynamical properties such as return map, bifurcation diagram, Lyapunov exponents, and basin of attraction are investigated. These maps belong to the hidden attractor category which is a newly introduced category of dynamical system.
Easily Cascaded Memristor-CMOS Hybrid Circuit for High-Efficiency Boolean Logic Implementation
Authors: Dong Zhekang , Qi Donglian , He Yufei , Xu Zhao , Hu Xiaofang , Duan Shukai
Published: November 2018

Memristor is a novel passive electronic element with resistance-switching dynamics. Due to the threshold property and the variable conductivity of the memristive element, its composite circuits are promising for the implementation of logic operations. In this paper, a flexible logic circuit based on the threshold-type memristor and the mature complementary metal-oxide-semiconductor (CMOS) technology is designed for the realization of Boolean logic operations. Specifically, the proposed method is able to perform the NAND, AND, OR, and NOR gate operations through two phases, i.e. the writing operation and the reading operation. In such implementation, the total delay is very small especially for time-sequence inputs. Furthermore, for existing memristor-based logic implementation, a contrastive analysis with relevant computer simulations is carried out. The experimental results indicate that the proposed method is capable of realizing all basic Boolean logic operations, and some more complicated cascaded logic operations with more compact circuit structures, higher efficiency, and lower operating cost.
Invariant Algebraic Surfaces and Hopf Bifurcation of a Finance Model
Authors: Cândido Murilo R. , Llibre Jaume , Valls Claudia
Published: November 2018

Recently there are several works studying the finance model [Formula: see text] where [Formula: see text] and [Formula: see text] are positive parameters. The first objective of this paper is to show that this model exhibits one small-amplitude periodic solution emerging from a Hopf bifurcation at the equilibrium point [Formula: see text] and in the second one we show that this system does not have invariant algebraic surfaces for any value of the parameters.
A Piecewise Linear Maximum Entropy Method for Invariant Measures of Random Maps with Position-Dependent Probabilities
Authors: Jin Congming , Upadhyay Tulsi , Ding Jiu
Published: November 2018

We present a numerical method for the approximation of absolutely continuous invariant measures of one-dimensional random maps, based on the maximum entropy principle and piecewise linear moment functions. Numerical results are also presented to show the convergence of the algorithm.
Impacts of Introducing Index Futures on Stock Market Volatilities: New Evidences from China
Authors: Gao Yang , Sun Bianxia
Published: November 2018

In April 2015, two index futures, IH and IC, respectively underlying big blue chip and small-medium stock indexes, were launched in China. However, because of a market crash, they came under strict control four months later. Using a panel-data evaluation approach, this paper examines how the introduction of IH and IC affect the volatility of their corresponding stocks. Results show that IH significantly reduces spot volatility before (after) a crash, but its function is significantly weakened during a crash. IC always fails to stabilize the spot market and even largely magnifies volatility during (after) a crash. Such different intervention effects on the two spot markets result mainly from the different levels of speculation on them.
Path-dependent martingale problems and additive functionals
Authors: Barrasso Adrien , Russo Francesco
Published: November 2018

The paper introduces and investigates the natural extension to the path-dependent setup of the usual concept of canonical Markov class introduced by Dynkin and which is at the basis of the theory of Markov processes. That extension, indexed by starting paths rather than starting points, will be called path-dependent canonical class. Associated with this is the generalization of the notions of semi-group and of additive functionals to the path-dependent framework. A typical example of such family is constituted by the laws [Formula: see text], where for fixed time [Formula: see text] and fixed path [Formula: see text] defined on [Formula: see text], [Formula: see text] is the (unique) solution of a path-dependent martingale problem or more specifically the weak solution of a path-dependent SDE with jumps, with initial path [Formula: see text]. In a companion paper we apply those results to study path-dependent analysis problems associated with BSDEs.
NEW SPIHT-BASED ALGORITHM FOR ELECTROCARDIOGRAM SIGNAL COMPRESSION
Authors: BOUKAACHE ABDELNOUR , DOGHMANE NOUREDDINE , BOUDJEHEM DJALIL
Published: November 2018

In this paper, we propose an electrocardiogram (ECG) signal compression algorithm that is based on wavelet and a new modified set partitioning in hierarchical trees (SPIHT) algorithm. The proposed algorithm contains a preprocessing of the approximation subband before the coding step by mean removing. Three other modifications are also introduced to the SPIHT algorithm. The first one is a new initialization of the two lists of insignificant points (LIP) and insignificant sets (LIS), while the second is concerning the position of inserting new entries of type [Formula: see text] at the LIS, and in the last one, the redundancy in checking type [Formula: see text] entries in the original method was found and avoided. The new proposed coding algorithm is applied to ECG signal compression and the obtained numerical results on the MIT-BIH database show the efficient performances of the proposed SPIHT algorithm over the original method and other existing methods.
EFFECT OF WEARING INSOLE WITH DIFFERENT DENSITY ON STANDING AND WALKING PLANTAR PRESSURE DISTRIBUTION
Authors: TAFTI NAHID , TURK SAJJAD BAYAT , HEMMATI FATEMEH , NOROUZI EHSAN , SHARIFMORADI KEYVAN , KARIMI MOHAMMAD TAGHI , KASHANI REZA VAHAB
Published: November 2018

Diabetic ulcers can lead to infection and amputation. Using insole can help to reduce and prevent foot ulceration and amputation in a diabetic patient. The aim of this study was to analyze the effect of wearing an insole with different density on standing and walking plantar pressure distribution. Methods: A group of 10 diabetic patients participated in this one-grouped before-after trial. Plantar pressure distribution was measured during walking and standing. Repeated Measure was used to test differences. Results: Repeated measure test showed that use of insole decreased foot pressure while walking significantly ([Formula: see text]). Pairwise comparison showed that wearing shoe insole with shore 30 decreased pressure compared to wearing shoe insole with shore 50 ([Formula: see text]) and walking without insole respectively ([Formula: see text]). Conclusion: The insole has more effect on plantar pressure during walking than standing, it also concluded that insole with shore 30 decreased pressure during walking more than that of the insole with shore 50. It could be said that patients who suffer from pain and discomfort on hind and forefoot may benefit insole with shore 30 to relieve from plantar pressure on the hindfoot and forefoot regions during standing and walking.
PALMAZ–SCHATZ STENT-OPENING MECHANICS USING A SIMPLE APPROACH INVOLVING THE BALLOON–STENT AND STENT–ARTERY CONTACT PROBLEM: APPLICATION TO BIOPOLYMER STENTS
Authors: BOKOV PLAMEN , DANTAN PHILIPPE , FLAUD PATRICE
Published: November 2018

We used the finite element method-based toolbox COMSOL Multiphysics to address the important question of biopolymer coronary stent mechanics. We evaluated the diameter of the stent, the immediate elastic recoil, the dogboning and the foreshortening during deployment while using an idealized model that took into account the presence of the balloon and the coronary artery wall (equivalent pressure hypothesis). We validated our model using the well-known mechanics of the Palmaz–Schatz metal stent and acquired new data concerning a poly-L-lactic acid (PLLA) stent and some other biodegradable co-polymer-based stents. The elastic recoil was relatively high (26.1% to 31.1% depending on the biopolymer used) when taking into account the presence of both the balloon and artery. The dogboning varied from 31% to 46% for the polymer stents and was 62% for the metal stent, suggesting that less arterial damage could be expected with biopolymer stents. Various strut thicknesses were tested for the PLLA stent (114, 180 and 250[Formula: see text][Formula: see text]m) and no significant improvement in elastic recoil was observed. We concluded that the stent geometry has a greater impact on the scaffolding role of the structure than the strut thickness, or even the mechanical properties of the stent.
Reaction force surface for the hydrogen transfer reaction in malonaldehyde: A classical wavefront-based formulation
Authors: Dey Bijoy K. , Shaw Shaquille
Published: November 2018

This paper investigates the simulation of a modified Hamilton–Jacobi equation in order to provide a classical wavefront-based formulation of reaction dynamics. Here, the wavefront is interpreted as minimizing a particular action functional. The method is rooted in the geometric optics and an eikonal equation is typically used for describing the light wave propagation. We have introduced a general formulation for reaction force surface (RFS) and a host of several force-based properties, which offer a reinvigorated understanding of the occurrence of a reaction event at molecular level. The calculation is performed on a model potential energy surface representing the hydrogen transfer reaction in malonaldehyde.
Occupation to Profession: The Need, Drivers and Course of Action for Regulating the South African Environmental Control Officer Industry
Authors: Wessels Johannes Albertus , Mostert Ruan Samson Colyn , Morrison-Saunders Angus
Published: November 2018

An unregulated Environmental Control Officer (ECO) industry is currently validating compliance to sustainability commitments made during the Environmental Impact Assessment (EIA) process of projects across South Africa. This paper follows an action research routine and explores the need and drivers for regulating professionalism of this industry. A self-administered survey questionnaire and interviews were used to generate empirical data from environmental practitioners. A total of 171 survey questionnaires were completed, and four interviews were conducted with key stakeholders. The data gathered were analysed and categorised in relation to theoretical perspectives on drivers for regulating verification professions within the context of attributes (or criteria) of a profession. To achieve the transition from an occupation to a profession, a six-step process is laid out tailored to meet the needs of the industry. This paper provides international environmental practitioners with insight to the need for regulating environmental verification industries such as ECOs.
Strengthening Climate Change Cooperation between China and India: Significance and Cooperation Areas
Authors: KANG Wenmei , WANG Mou
Published: November 2018

In international climate negotiations, China and India are both members of the BASIC countries and Like Minded Group of Developing Countries (LMDC). In recent years, due to the different development levels, the two countries have differed in issues such as willingness to reduce emissions, peak emissions and funding. China tends to engage in international climate governance with a more proactive approach, while India, constrained by its development level, has continued to emphasize the traditional stance of a developing country. Although differences between the two sides on some issues have not yet led to the collapse of China–India climate cooperation, more efforts need to be made to further analyze and define the pursuits of both sides, future trends in their cooperation and priority areas for collaboration. In the authors’ opinion, the two countries still have common ground in seeking further socio-economic development and getting emission allowances, which will serve as the foundation for future climate cooperation. Strengthening the cooperation between China and India on climate change will not only help unite developing countries to fight for and safeguard their rights to equitable development, but also enhance the cooperative actions and bilateral ties between the two countries. Moreover, the cooperation may as well work as a potential platform where China can disseminate the idea of ecological civilization and promote the shift towards a green and low-carbon development model. In the post-Paris Agreement era, China should maintain and advance its cooperation with India on climate change, strengthen existing cooperation mechanisms and launch pragmatic cooperation programs in regard to equitable development, the utilization of renewable resources and research on ecological civilization.
Modeling the Human-Robot Trust Phenomenon
Authors: Wagner Alan R. , Robinette Paul , Howard Ayanna
Published: November 2018

This article presents a conceptual framework for human-robot trust which uses computational representations inspired by game theory to represent a definition of trust, derived from social psychology. This conceptual framework generates several testable hypotheses related to human-robot trust. This article examines these hypotheses and a series of experiments we have conducted which both provide support for and also conflict with our framework for trust. We also discuss the methodological challenges associated with investigating trust. The article concludes with a description of the important areas for future research on the topic of human-robot trust.
Central Heating System Constrained Control with Input Delay Based on Neural Networks
Authors: Wang Hongwei , Tu Fangwen , Feng Guohui , Ao Xin
Published: November 2018

An output constrained control with input delay is proposed for a central heating system. Due to the delay of signal transmission and valves opening time, an input delay is considered into the system and an auxiliary system is employed to handle this issue by converting the delayed input into a delay-free one. Moreover, to ensure the output supply water temperature within a limited range, Barrier Lyapunov algorithm is involved to achieve desired control accuracy. Finally, external disturbance and model uncertainty are incorporated into the dynamic system and neural networks (NN) are trained in an online fashion for the compensation. The stability of the control system is guaranteed through rigorous Lyapunov analysis and the excellent control performance over traditional PID control is demonstrated via numerical simulation study.