bluuebunny/crossref_metadata_2025 huggingface dataset:
Rotational and relative translational control for satellite electromagnetic formation flying in low earth orbit
Authors: Fan Li , Hu Min , Yang Mingqi
Published: September 2017

Purpose

The purpose of this paper is to develop a theoretical design for the attitude control of electromagnetic formation flying (EMFF) satellites, present a nonlinear controller for the relative translational control of EMFF satellites and propose a novel method for the allocation of electromagnetic dipoles.

Design/methodology/approach

The feedback attitude control law, magnetic unloading algorithm and large angle manoeuvre algorithm are presented. Then, a terminal sliding mode controller for the relative translation control is put forward and the convergence is proved. Finally, the control allocation problem of electromagnetic dipoles is formulated as an optimization issue, and a hybrid particle swarm optimization (PSO) – sequential quadratic programming (SQP) algorithm to optimize the free dipoles. Three numerical simulations are carried out and results are compared.

Findings

The proposed attitude controller is effective for the sun-tracking process of EMFF satellites, and the magnetic unloading algorithm is valid. The formation-keeping scenario simulation demonstrates the effectiveness of the terminal sliding model controller and electromagnetic dipole calculation method.

Practical implications

The proposed method can be applied to solve the attitude and relative translation control problem of EMFF satellites in low earth orbits.

Originality/value

The paper analyses the attitude control problem of EMFF satellites systematically and proposes an innovative way for relative translational control and electromagnetic dipole allocation.
Real-time modeling of retractable self-launching glider using spreadsheets
Authors: Nogoud Yasser A. , Jonker Attie , Mansor Shuhaimi , Abuelnuor A.A.A.
Published: September 2017

Purpose

This paper aims to propose a spreadsheet method for modeling and simulation of a retraction system mechanism for the retractable self-launching system for a high-performance glider.

Design/methodology/approach

More precisely, the method is based on parametric link design using Excel spreadsheets.

Findings

This method can be used for kinematic and dynamic analysis, graphical plotting and allows simulation of control kinematics with the ability to make quick and easy parametric changes to a design. It also has the ability to calculate the loads imposed on each component in the control system as a function of input loads and position.

Practical implications

This paper shows that it is possible to model complex control systems quickly and easily using spreadsheet programs already owned by most small companies. The spreadsheet model is a parametric model, and it gives a simple visual presentation of the control system with interactive movement and control by the user.

Originality/value

This spreadsheet model in conjunction with a simple CAD program enables the rapid and cost-effective development of control system components.
Deployment and control of cable-driven flexible solar arrays
Authors: Li Haiquan , Duan Liucheng , Liu Xiaofeng , Cai Guoping
Published: September 2017

Purpose

The purpose of this study is to investigate the deployment and control of cable-driven flexible solar arrays.

Design/methodology/approach

First, dynamic model of the system is established by using the Jourdain’s velocity variation principle and the single direction recursive construction method, including the dynamic equation of a single flexible body, the kinematical recursive relation of two adjacent flexible bodies and the dynamic equation of the solar array system. Then, the contribution of joint friction to the dynamic equation of the system is derived based on the virtual power principle. A three-dimensional revolute joint model is introduced and discussed in detail. Finally, a proportion-differentiation (PD) controller is designed to control the drift of the system caused by the deployment.

Findings

Simulation results show that the proposed model is effective to describe the deployment of flexible solar arrays, joint friction may affect the dynamic behavior of the system and the PD controller can effectively eliminate the spacecraft drift.

Practical implications

This model is useful to indicate the dynamics behavior of the solar array system with friction.

Originality/value

The relationship between ideal constraint force and Lagrange multipliers is derived. The contribution of joint friction to the dynamic equation of the system is derived based on the virtual power principle. A PD controller is designed to control the drift of the system caused by the deployment of solar arrays.
Hybrid BTT/STT missile autopilot design
Authors: Bai Chengchao , Lu Fei , Xu Xibao
Published: September 2017

Purpose

Traditional skid-to-turn (STT) missile control mode is adopted mostly, but with the improvement of requirements for mobility and the emergence of new aerodynamic layout, a bank-to-turn (BTT) control mode gradually shows a greater advantage. However, the BTT missile also has certain defects, for example, when attacking against a maneuvering target and at the last section of guidance, the maximum lifting surface position of the missile needs to be adjusted frequently, thereby increasing the difficulty of control as well as introducing high-frequency noise.

Design/methodology/approach

Based on respective characteristics of the two control modes, this paper puts forward a hybrid autopilot design method based on nonlinear dynamic inversion. Firstly, the method converts overload instructions into corresponding angle instructions through the design of hybrid control guidance logic; secondly, based on the nonlinear dynamic inversion algorithm and combined with the fast-changing circuit/slowly changing circuit, a hybrid controller is designed; finally, combined with the missile mathematical model and actuator, it forms a autopilot design closed loop.

Findings

The simulation result shows that the non-linear dynamic inverse-based BTT/STT hybrid controller can input a track command well, normal overload and roll angle tracking performance have more advantages than the hybrid controller designed on the basis of classical control method in terms of overshooting and hysteretic characteristics.

Originality/value

The paper puts forward a new BTT/STT hybrid control method which has both the high mobile ability of the BTT missile and the precise control ability of the STT missile, which can adapt to the more complicated fighting environment. And, the method can effectively weaken the impact of the transformation of the control mode on the system.
Identification of mechanical properties of adhesive joints using ANN
Authors: Pazand Kamran , Nobari A.S.
Published: September 2017

Purpose

This paper aims to present a new approach to the fast determination of the effective, dynamic, mechanical properties of an adhesive for linear and nonlinear regions of the adhesive response, for both healthy and damaged states of the bond.

Design/methodology/approach

The proposed approach is based on the measurement of the linear and nonlinear frequency response function (FRF) of adhesive-bonded structure and using artificial neural network identification technique. For this purpose, linear and nonlinear FRFs are measured for several single-lap joint specimens that are fabricated in healthy and damaged configurations of the bond. The measured FRFs of healthy and damaged specimens are then used to identify the natural frequencies of the specimens. The experimental natural frequencies, in turn, would be used to train artificial neural network (ANN) which would be able to predict the effective Young’s and shear moduli and damping of adhesive in healthy and damaged specimens, for any given excitation level and frequency, within the training domain.

Findings

Simultaneous identification of the effective mechanical properties of adhesive for linear and nonlinear response regions, as well as healthy and damages states of the adhesive bond.

Practical implications

The introduced method is effective to model the assembled structures with the viscoelastic adhesive joints, for linear and nonlinear regions.

Originality/value

A fast methodology, using ANN, for identification the effective mechanical properties of adhesives, compared to other methods for both linear and nonlinear regions.
Design and analysis osculating general curved cone waverider
Authors: He Xuzhao , Le Jialing , Qin Si
Published: September 2017

Purpose

Waverider has high lift to drag ratio and will be an idea aerodynamic configuration for hypersonic vehicles. But a structure permitting aerodynamic like waverider is still difficult to generate under airframe’s geometric constrains using traditional waverider design methods. And furthermore, traditional waverider’s aerodynamic compression ability cannot be easily adjusted to satisfy the inlet entrance requirements for hypersonic air-breathing vehicles. The purpose of this paper is to present a new method named osculating general curved cone (OCC) method aimed to improve the shortcomings of traditional waveriders.

Design/methodology/approach

A basic curved cone is, first, designed by the method of characteristics. Then the waverider’s inlet captured curve and front captured tube are defined in the waverider’s exit plane. Osculating planes are generated along the inlet captured curve and the designed curved cone is transformed to the osculating planes. Streamlines are traced in the transformed curved cone flow field. Combining all streamlines which have been obtained, OCC waverider’s compression surface is generated. Waverider’s upper surface uses the free stream surface.

Findings

It is found that OCC waverider has good volumetric characteristics and good flow compression abilities compared with the traditional osculating cone (OC) waverider. The volume of OCC waverider is 25 per cent larger than OC waverider at the same design condition. Furthermore, OCC waverider can compress incoming flow to required flow conditions with high total pressure recovery in the waverider’s exit plane. The flow uniformity in the waverider exit plane is quite well.

Practical implications

The analyzed results show that the OCC waverider can be a practical high performance airframe/forebody for hypersonic vehicles. Furthermore, this novel waverider design method can be used to design a structure permitting aerodynamic like waverider for a practical hypersonic vehicle.

Originality/value

The paper puts forward a novel waverider design method which can improve the waverider’s volumetric characteristics and compression abilities compared with the traditional waverider design methods. This novel design approach can extend the waverider’s applications for designing hypersonic vehicles.
A hybrid Krylov-subspace-exponential and finite-difference time integration approach for multiscale electromagnetic simulations
Authors: Wang Jiawei , Chen Feng , Shao Jinghui , Zhang Weichen , Ma Xikui
Published: September 2017

Purpose

This paper aims to present a novel hybrid time integration approach for efficient numerical simulations of multiscale problems involving interactions of electromagnetic fields with fine structures.

Design/methodology/approach

The entire computational domain is discretized with a coarse grid and a locally refined subgrid containing the tiny objects. On the coarse grid, the time integration of Maxwell’s equations is realized by the conventional finite-difference technique, while on the subgrid, the unconditionally stable Krylov-subspace-exponential method is adopted to breakthrough the Courant–Friedrichs–Lewy stability condition.

Findings

It is shown that in contrast with the conventional finite-difference time-domain method, the proposed approach significantly reduces the memory costs and computation time while providing comparative results.

Originality/value

An efficient hybrid time integration approach for numerical simulations of multiscale electromagnetic problems is presented.
Numerical analysis of electromagnetic field in devices with the high-speed unit
Authors: Shao Jinghui , Kang Zhen , Wang Jiawei , Ma Xikui
Published: September 2017

Purpose

The purposes of this paper are to numerically analyse the distribution of the electromagnetic field in the electromagnetic device wherein a high-speed unit exists and to develop a strong tool to analyse the evolution of an electromagnetic field tangled with moving parts.

Design/methodology/approach

The precise integration time domain (PITD) method and parameter weighted averaging approximation scheme.

Findings

It is shown that that the electromagnetic field in the device is significantly affected by the velocity of the moving unit and the parameters of the base material. The computation resources of the proposed method are saved and the efficiency is enhanced.

Originality/value

The parameter approximation (PA)-PITD method can be an effective and efficient time domain method to analyse the evolution of the electromagnetic field in electromagnetic devices with moving parts and similar problems.
Simulation on motion characteristics of space charge in single oil-paper insulation
Authors: Yang Zhifei , Du Zhiye , Ruan Jiangjun , Jin Shuo , Huang Guodong , Lian Qixiang , Liao Yifan
Published: September 2017

Purpose

The purpose of this paper is numerical calculation of total electric field in oil-paper insulation. Now, there is no effective method to consider the influence of space charges when calculating the total electric field distribution in the main insulation system of the valve-side winding of an ultra-high-voltage direct current converter transformer.

Design/methodology/approach

To calculate the total electric field in an oil-paper insulation system, a new simulation method in single-layer oil-paper insulation based on the transient upstream finite element method (TUFEM) is proposed, in which the time variable is considered. The TUFEM is used to calculate the total electric field in an oil-paper insulation system by considering the move law of space charges. The simulation method is verified by comparing the simulation results to the test data. The move law of space charges and distribution characteristics of the electric field under difference voltage values in single-layer oil-paper insulation were presented.

Findings

The results show that the TUFEM has an excellent accuracy compared with the test data. When carrier mobility is a constant, the time to reach the steady state is inversely correlated with the initial electric field intensity, and the distortion rate of the internal total electric field is positively correlated with the initial electric field intensity.

Originality/value

This paper provides an exploratory research on the simulation of space charge transport phenomenon in oil-paper and has guiding significance to the design of oil-paper insulation.
Fast analytical calculation method for eddy current induced by gradient fields in an MRI system
Authors: Xu Zheng , Wu Jiamin , Li Lu , He Yucheng , He Wei , Yu Dengjie
Published: September 2017

Purpose

Eddy currents are inevitable in magnetic resonance imaging (MRI) systems. These currents are mainly induced by gradient fields. This study aims to propose a fast analytical method to calculate eddy currents induced by frequently switching gradient fields in a traditional C-shape MRI system.

Design/methodology/approach

Fourier decomposition and magnetic vector potentials were used to calculate the eddy currents. Calculations with the proposed analytical method revealed the spatial distribution and temporal evolution of eddy currents.

Findings

Calculation and Maxwell simulation results were consistent. The agreement between calculation and simulation results indicates that increasingly sophisticated structures could be developed. The calculated results could guide the design of improved gradient coils.

Originality/value

Eddy currents induced by gradient current are decomposed into currents induced by each time-harmonic component, and then adding them together to obtain complete contribution of the eddy current. The analytical method was used to characterize the properties of symmetric and asymmetric eddy currents induced by gradient coils in MRI systems. The analytical method can be used to improve the gradient shield during the design of the gradient coil in the MRI system.
A novel saturated open-core fault current limiter and its nonlinear magnetic circuit model
Authors: Li Lei , Li Lin
Published: September 2017

Purpose

This paper aims to present a novel energy-efficient saturated open-core fault current limiter (FCL) with special permanent magnet (PM) modules.

Design/methodology/approach

The special PM modules are used to drive the cores of FCL into a saturated state from different directions in the normal operation condition, reducing the DC current of the saturated open-core FCL. An equivalent magnetic circuit model of the saturated open-core FCL with PM modules is built to calculate the magnetic flux density in the cores of FCL. By applying the modified nodal approach on the circuit, the nonlinear equations of the magnetic circuit can be achieved. The Newton – Raphson method is used to solve the nonlinear equations. The model shows good accuracy verified by finite element simulation and a physical experiment.

Findings

Compared with the original saturated open-core FCL structure with PMs, the novel saturated open-core FCL structure can save 84% DC power. The physical experiment results show that the saturated open-core FCL has a good performance on limiting the fault current.

Originality/value

A novel saturated open-core FCL structure with PM modules is proposed in this paper. A physical model of the saturated open-core FCL structure with PM modules is manufactured and tested. About 84% DC power can be reduced by using the PM modules in this saturated open-core FCL, and it can save most of the cost of the saturated open-core FCL.
Measurement and modelling of rotational anomalous loss considering skin effect of electrical steel sheets
Authors: Li Jingsong , Wang Lixiang , Yang Qingxin , Wang Shanming , Li Yongjian , Zhang Changgeng , Qu Baojun
Published: September 2017

Purpose

Due to existence of skin effect under rotational excitation, especially to high-frequency motors and power transformers run at the frequency of hundreds or even thousands of hertz, core losses will increase significantly, which may cause local overheating damage, and the efficiency and longevity will be decreased. The purpose of this paper is to accurately calculate the rotational anomalous loss in electrical steel sheets.

Design/methodology/approach

The influence of skin effect to rotational anomalous loss coefficient is described in detail. Based on the rotational core losses calculation approach, the transformed coefficient and parameters of rotational anomalous loss are determined in accordance with experimental data obtained by using 3D magnetic properties testing system. Then, a variable loss coefficient calculation model of rotational anomalous loss is built. Meanwhile, a separation of the total 2D elliptical rotation experimental core losses is worked out.

Findings

The two methods are analysed and compared qualitatively. It should be noted that the novel calculation model can be more effectively presented anomalous loss features. Moreover, quantitative comparisons between 2D elliptical rotation and alternating core losses have achieved beneficial conclusions.

Originality/value

Transformed rotational anomalous loss coefficient and parameters of electrical steel sheets considering skin effect are determined. Based on that, a novel calculation model evaluating 2D elliptical rotation anomalous loss is presented and verified based on the experimental measurement and the separation of the total 2D elliptical rotation core losses. The 2D elliptical rotation core losses separation method and quantitative comparison with alternating excitation are helpful to engineering application.
The study of design and harmonic suppression for 800 kV EHV MSCR in engineering applications
Authors: Wang Qingpeng , Bai Baodong , An Zhen , Chen Dezhi
Published: September 2017

Purpose

The purpose of this paper is to solve the reactive power adjustment and the overvoltage suppression problems in the extra high voltage (EHV) long distance grid, which often appears transient overvoltage, light load loss and other issues.

Design/methodology/approach

One 800 kV EHV magnetically saturation controllable reactor (MSCR) used self-power supply control system is designed. The structure and the working mechanism of the novel MSCR are analyzed in detail. Then the control and capacity step adjustment characteristics are obtained by experiments. The harmonic characteristic is studied by theoretical analysis and low voltage test.

Findings

To solve the problem of harmonics in the working current of nets windings, the fifth and the seventh filers are equipped between the compensation windings and the control system. The effectiveness of the harmonic suppression method is proved by simulation and experiments.

Originality/value

It proves that the 800 kV EHV MSCR design in this paper can achieve the purpose of the reactive power continuous linear adjustment, and the capacity adjustment is sensitive. After filtering, the harmonics level of the working current meets the standard of the EHV grid.
Event and community involvement of sport event volunteers
Authors: Hallmann Kirstin , Zehrer Anita
Published: September 2017

Purpose

The purpose of this paper is to investigate the potential interrelationship between different types of volunteer involvement (event involvement and community involvement) and their impact on the behavioural intentions of different types of events.

Design/methodology/approach

By means of a survey, data from an one-off sport event (n=316), including volunteer tourists, and from annual sport events (n=278) in Germany were collected. Structural equation modelling was employed for data analysis.

Findings

Findings show that event involvement and community involvement are significantly correlated. Both influence future behavioural intentions for one-off events. But only event involvement and not community involvement influences behavioural intentions for annual events.

Research limitations/implications

The findings are underpinning the rationale of social identity theory from a theoretical perspective.

Practical implications

Volunteer managers learn that not only the volunteers’ involvement with event organisations, but also with the community (i.e. hosting destination) seems to be a key contributor of behavioural intentions and should therefore be fostered during the recruitment process and prior to the event.

Originality/value

This study is the first to compare involvement with two objects for different types of events. Therefore, this study adds to the rare literature looking at different event types in which an individual can volunteer.
The validity of two diagnostic systems for personality disorder in people with intellectual disabilities: a short report
Authors: Lindsay William R. , van Logten Anne , Didden Robert , Steptoe Lesley , Taylor John L. , Hogue Todd E.
Published: September 2017

Purpose

Over the last ten years, there has been greater interest in the diagnosis of personality disorder (PD) in people with intellectual and developmental disabilities (IDD). One important characteristic of a diagnostic system is that it should have validity as a contribution to utility. PD has been found to have a predictive relationship with violence and the purpose of this paper is to review two methods for the diagnosis of PD in offenders with IDD in order to evaluate the utility of the diagnoses.

Design/methodology/approach

In total, 212 offenders with ID were recruited from three settings – maximum-security, medium/low security and community services. Diagnoses of PD in the case files were compared with a structured system of diagnosis based on DSM-IV traits.

Findings

There were significant differences between the two systems with a significantly higher frequency of PD diagnosis in the community forensic setting in the structured assessment system. There was no relationship between the case files diagnosis of PD and future violence but there was a significant predictive relationship between the structured diagnosis of PD and future violence with an AUC=0.62.

Research limitations/implications

As with all such studies, the research is limited by the quality of the case files available to the researchers.

Practical implications

Only the structured assessment of PD had utility for the prediction of violence. Reasons for the differences between the systems are discussed and suggestions made on how a diagnosis of PD can be structured for the busy clinician.

Social implications

The accurate diagnosis of PD has important implications since the PD is a crucial addition to any violence risk evaluation.

Originality/value

This study is the first of its kind to review the way in which clinicians assess PD.
Social-moral awareness and theory of mind in adult offenders who have intellectual disabilities
Authors: Hammond Sarah , Beail Nigel
Published: September 2017

Purpose

There has been little empirical investigation into the theoretical relationship between moral reasoning and offending in people with intellectual disabilities (ID). The purpose of this paper is to compare offending and non-offending ID groups on a new measure of social-moral awareness, and on theory of mind (ToM).

Design/methodology/approach

A between groups design was used. The scores of 21 male offenders and 21 male non-offenders, all with ID and matched for IQ, were compared on the Social-Moral Awareness Test (SMAT) and on two ToM tasks.

Findings

There was no significant difference in SMAT scores or on first- or second-order ToM tasks between offending and non-offending groups. Better ToM performance significantly predicted higher SMAT scores and non-offending groups. Better ToM performance significantly predicted higher SMAT scores.

Research limitations/implications

Results were inconsistent with previous research. Further work is required to establish the validity and theoretical underpinnings of the SMAT. Development in the measurement of ToM for people with ID is also required.

Originality/value

This is the first use of the SMAT with a population of offenders who have ID. The findings suggest caution in its use in clinical settings.
Gen Y-ers’ brand loyalty drivers in emerging devices
Authors: Giovanis Apostolos , Athanasopoulou Pinelopi
Published: September 2017

Purpose

In emerging devices (smartphones, tablets, and notebooks) markets, increasing brand loyalty is critical for suppliers. Generation Y (Gen Y) is the first global target group and the best customer segment for emerging devices. The purpose of this paper is to propose a conceptual framework that assesses the brand value of emerging devices as perceived by Gen Y-ers, identify the components that contribute to its formulation, and investigate its relative influence on the development of brand relationships, represented by satisfaction and brand trust, and on brand loyalty.

Design/methodology/approach

A mall-intercept survey of a sample of 1,109 Gen Y consumers was implemented using a structured questionnaire with established scales. Data were analyzed with PLS-PM, a SEM methodology.

Findings

Results show that brand satisfaction and reliability are the main drivers of Gen Y-ers’ brand loyalty followed by brand intentions, while both trust dimensions (reliability and intentions) and satisfaction partially mediate the relationship between brand value and brand loyalty. Brand value is also directly related to brand loyalty irrespective of consumer-brand relationship quality. Also, functional value-quality and emotional value are shown to be the most important components for brand value formulation followed by functional value-price and brand reputation (BRP) whereas symbolic value is the least important.

Research limitations/implications

The sample is country specific and this may affect generalizability of findings. Also, the cross-sectional design adopted does not reflect temporal changes.

Practical implications

Emerging devices should provide customers both functional (e.g. advanced features, attractive style, quality, durability) and emotional (entertainment, communication) benefits in order to increase brand loyalty. Furthermore, firms should manage their BRP since it can affect significantly brand value, customer-brand relationship quality, and brand loyalty.

Originality/value

The model developed provides a useful guideline for marketers in identifying the most important brand benefits for Gen Y-ers for developing relationships and stay loyal to a brand.
Plant Polyphenols as Antioxidant and Antibacterial Agents for Shelf‐Life Extension of Meat and Meat Products: Classification, Structures, Sources, and Action Mechanisms
Authors: Papuc Camelia , Goran Gheorghe V. , Predescu Corina N. , Nicorescu Valentin , Stefan Georgeta
Published: September 2017

Oxidative processes and meat spoilage bacteria are major contributors to decreasing the shelf‐life of meat and meat products. Oxidative processes occur during processing, storage, and light exposure, lowering the nutritional and sensory value and acceptability of meat and generating toxic compounds for humans. Polyphenols inhibit oxidative processes in 3 ways: as reactive species scavengers, lipoxygenase inhibitors, and reducing agents for metmyoglobin. Thus, polyphenols are candidate antioxidants for meat and meat products. The cross‐contamination of meat with spoilage and pathogenic microorganisms can occur in production lines and result in economic losses. The ability of polyphenols to interact with bacterial cell wall components and the bacterial cell membrane can prevent and control biofilm formation, as well as inhibit microbial enzymes, interfere in protein regulation, and deprive bacterial cell enzymes of substrates and metal ions. Thus, polyphenols are candidate antimicrobial agents for use with meat and meat products. Commercially available polyphenols can decrease primary and secondary lipid peroxidation levels, inhibit lipoxygenase activity, improve meat color stability, minimize the degradation of salt‐soluble myofibrillar protein and sulfhydryl groups, and retard bacterial growth. Further studies are now needed to clarify the synergistic/antagonistic action of various polyphenols, and to identify the best polyphenol classes, concentrations, and conditions of use.
The Causal Role of Alcohol Use in Adolescent Externalizing and Internalizing Problems: A Mendelian Randomization Study
Authors: Chao Miao , Li Xinying , McGue Matt
Published: September 2017

Background

The co‐occurrence of alcohol use and externalizing/internalizing problems threatens adolescents’ mental health. Research on whether alcohol use and these problems are causal and the direction of the potential causal relationships is needed to understand the mechanisms of the co‐occurrence.

Methods

A Mendelian randomization analysis was conducted in which the aldehyde dehydrogenase 2 (ALDH2) rs671 polymorphism was used as an instrumental variable for alcohol use phenotypes. In total, 1,608 Chinese adolescents (mean age 14.11 ± 1.83 years) were genotyped for the ALDH2 rs671 polymorphism. Three externalizing problems (aggression, delinquency, and attention problems) were measured with the Youth Self‐Report inventory, and 2 internalizing problems (depression and anxiety) were measured with the self‐reported Children's Depression Inventory and the Trait subscale of the State‐Trait Anxiety Inventory.

Results

Alcohol use was positively associated with all 3 externalizing and 2 internalizing problems, and the ALDH2 polymorphism had a significant effect on alcohol use. Aggression and attention problems were also significantly affected by the ALDH2 polymorphism, whereas no significant association was observed between the ALDH2 polymorphism and delinquency, anxiety, or depression.

Conclusions

The results suggest that alcohol use is a cause of adolescent aggression and attention problems but not adolescent delinquency, anxiety, or depression.
Neurotensin in the posterior thalamic paraventricular nucleus: inhibitor of pharmacologically relevant ethanol drinking
Authors: Pandey Surya , Badve Preeti S. , Curtis Genevieve R. , Leibowitz Sarah F. , Barson Jessica R.
Published: September 2017

Individuals prone to ethanol overconsumption may have preexisting neurochemical disturbances that contribute to their vulnerability. This study examined the paraventricular nucleus of the thalamus (PVT), a limbic structure recently shown to participate in ethanol intake. To identify individuals prone to ethanol overconsumption, we tested Long–Evans rats in behavioral paradigms and found high levels of vertical time (rearing behavior) in a novel activity chamber to be a consistent predictor of subsequent excessive 20 percent ethanol drinking under the intermittent access model. Examining neurochemicals in the PVT, we found before ethanol exposure that prone rats with high rearing, compared with non‐prone rats, had significantly lower levels of neurotensin (NTS) mRNA and peptide in the posterior (pPVT) but not anterior (aPVT) subregion of the PVT. Our additional finding that ethanol intake has no significant impact on either rearing or NTS levels indicates that these measures, which are different in prone rats before ethanol consumption, remain stable after ethanol consumption. The possibility that NTS directly controls ethanol drinking is supported by our finding that NTS administration specifically suppresses ethanol drinking when injected into the pPVT but not aPVT, with this effect occurring exclusively in higher drinkers that presumably have lower endogenous levels of NTS. Further, an NTS antagonist in the pPVT augments intake in lower drinkers with presumably more endogenous NTS, while NTS in the pPVT inhibits novelty‐induced rearing that predicts excessive drinking. Together, these results provide strong evidence that low endogenous levels of NTS in the pPVT contribute to an increased propensity toward excessive ethanol drinking.
‘It's like a frog leaping about in your chest’: Illness and treatment perceptions in persistent atrial fibrillation
Authors: Taylor Elaina C. , O'Neill Mark , Hughes Lyndsay D. , Carroll Susan , Moss‐Morris Rona
Published: September 2017

Objectives

Persistent atrial fibrillation (AF) is an abnormal heart rhythm associated with low quality of life (QoL) and significant health‐related costs. The purpose of the study was to examine patients’ illness and treatment beliefs and ways of coping with AF symptoms, to provide insight into promoting better QoL and treatment‐specific management.

Design

Beliefs were explored across three procedural treatment groups using a qualitative cross‐sectional design.

Methods

Thirty semi‐structured interviews were carried out with patients undertaking cardioversion (n = 10), catheter ablation (n = 11) and atrioventricular node ablation (n = 9). Interviews were transcribed and analysed using inductive thematic analysis with elements of grounded theory.

Results

An overarching theme of a vicious cycle was evident, which related to perceived lack of knowledge and understanding of AF, attempts to control symptoms and negative emotional reactions to failed control attempts. This vicious cycle related to three subordinate themes: (1) unpredictability and uncertainty of AF and symptoms; (2) coping with symptoms through (a) avoidance (b) all‐or‐nothing‐ (c) slowing down behaviours; and (3) concerns and expectations about treatment.

Conclusions

Patients outlined a need to gain control of unpredictable symptoms by monitoring and varying activity levels. These behaviours were often appraised as ineffective at controlling symptoms, leading to heightened uncertainty and increased activity avoidance. Treatment concerns escalated with increasing number and invasiveness of procedures. Improving AF patients’ perceived understanding of their illness and treatment and promoting more effective symptom‐management strategies may alleviate psychological distress and improve QoL. Themes elaborated on the common‐sense model whereby patients’ beliefs about illness and treatment interact with coping behaviours.

Statement of contribution

What is already known about this subject?

Quality of life (QoL) is disproportionately low in people with persistent atrial fibrillation (psAF).

The common‐sense model suggests illness perceptions and coping predict QoL in chronic illnesses.

No previous studies have examined the idiosyncratic beliefs and coping behaviours of psAF patients.

What does this study add?

A vicious cycle of perceived lack of understanding of AF, attempts to control AF and distress at failed attempts at control, was a key theme.

PsAF patients reported continued avoidance/all‐or‐nothing behaviours despite symptomatic relief post‐procedure, and disengagement from enjoyable activities.

PsAF patients reported procedure‐specific concerns/expectations, which could be targeted in future interventions aimed at reducing distress.
Selective HDAC6 inhibition decreases early stage of lupus nephritis by down-regulating both innate and adaptive immune responses
Authors: Ren J , Liao X , Vieson M D , Chen M , Scott R , Kazmierczak J , Luo X M , Reilly C M
Published: September 2017

We have demonstrated previously that histone deacetylase (HDAC6) expression is increased in animal models of systemic lupus erythematosus (SLE) and that inhibition of HDAC6 decreased disease. In our current studies, we tested if an orally active selective HDAC6 inhibitor would decrease disease pathogenesis in a lupus mouse model with established early disease. Additionally, we sought to delineate the cellular and molecular mechanism(s) of action of a selective HDAC6 inhibitor in SLE. We treated 20-week-old (early-disease) New Zealand Black (NZB)/White F1 female mice with two different doses of the selective HDAC6 inhibitor (ACY-738) for 5 weeks. As the mice aged, we determined autoantibody production and cytokine levels by enzyme-linked immunosorbent assay (ELISA) and renal function by measuring proteinuria. At the termination of the study, we performed a comprehensive analysis on B cells, T cells and innate immune cells using flow cytometry and examined renal tissue for immune-mediated pathogenesis using immunohistochemistry and immunofluorescence. Our results showed a reduced germinal centre B cell response, decreased T follicular helper cells and diminished interferon (IFN)-γ production from T helper cells in splenic tissue. Additionally, we found the IFN-α-producing ability of plasmacytoid dendritic cells was decreased along with immunoglobulin isotype switching and the generation of pathogenic autoantibodies. Renal tissue showed decreased immunoglobulin deposition and reduced inflammation as judged by glomerular and interstitial inflammation. Taken together, these studies show selective HDAC6 inhibition decreased several parameters of disease pathogenesis in lupus-prone mice. The decrease was due in part to inhibition of B cell development and response.
Incorporating fragmentation and non‐native species into distribution models to inform fluvial fish conservation
Authors: Taylor Andrew T. , Papeş Monica , Long James M.
Published: September 2017

Fluvial fishes face increased imperilment from anthropogenic activities, but the specific factors contributing most to range declines are often poorly understood. For example, the range of the fluvial‐specialist shoal bass (Micropterus cataractae) continues to decrease, yet how perceived threats have contributed to range loss is largely unknown. We used species distribution models to determine which factors contributed most to shoal bass range loss. We estimated a potential distribution based on natural abiotic factors and a series of currently occupied distributions that incorporated variables characterizing land cover, non‐native species, and river fragmentation intensity (no fragmentation, dams only, and dams and large impoundments). We allowed interspecific relationships between non‐native congeners and shoal bass to vary across fragmentation intensities. Results from the potential distribution model estimated shoal bass presence throughout much of their native basin, whereas models of currently occupied distribution showed that range loss increased as fragmentation intensified. Response curves from models of currently occupied distribution indicated a potential interaction between fragmentation intensity and the relationship between shoal bass and non‐native congeners, wherein non‐natives may be favored at the highest fragmentation intensity. Response curves also suggested that >100 km of interconnected, free‐flowing stream fragments were necessary to support shoal bass presence. Model evaluation, including an independent validation, suggested that models had favorable predictive and discriminative abilities. Similar approaches that use readily available, diverse, geospatial data sets may deliver insights into the biology and conservation needs of other fluvial species facing similar threats.
The effects of pirfenidone in patients with an acute exacerbation of interstitial pneumonia
Authors: Matsumura Takuma , Tsushima Kenji , Abe Mitsuhiro , Suzuki Kenichi , Yamagishi Kazutaka , Matsumura Akane , Ichimura Yasunori , Ikari Jun , Terada Jiro , Tatsumi Koichiro
Published: September 2017

Introduction

The prognosis of patients with an acute exacerbation of interstitial pneumonia (AE‐IP) is poor. Pirfenidone (PFD) reduces the disease progression in idiopathic pulmonary fibrosis.

Objectives

The purpose of this study was evaluating whether the administration of PFD improved the outcomes of AE‐IP.

Methods

We conducted a retrospective study of 31 patients with AE‐IP who did not recover between 7 and 14 days after an initial treatment. Fourteen patients received PFD within 2 weeks (PFD group) of the AE, while 17 patients were treated without PFD (non‐PFD group). The patients’ clinical data and computed tomography (CT) scores were analyzed.

Results

The survival rate in the PFD group was not significantly different from non‐PFD group at 30 (78.6% vs 64.7%, P = .46) and 90 days (64.3% vs 52.9%, P = .72). The white blood cell counts in the PFD group were significantly lower on PFD day 14 than on PFD days 1 and 7. The C‐reactive protein levels in the PFD group were also significantly lower on PFD day 7 than on PFD day 1. There were no significant differences regarding the changes of the CT scores.

Conclusions

PFD may reduce the inflammation in AE‐IP patients undergoing corticosteroid treatment.
Zenker's diverticulum: Submucosal tunneling endoscopic septum division (Z‐POEM)
Authors: Hernández Mondragón Oscar Víctor , Solórzano Pineda Michel Omar , Blancas Valencia Juan Manuel
Published: September 2017

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Cognitive functioning over 2 years after intracerebral hemorrhage in school‐aged children
Authors: Murphy Lexa K , Compas Bruce E , Gindville Melissa C , Reeslund Kristen L , Jordan Lori C
Published: September 2017

Aim

Previous research investigating outcomes after pediatric intracerebral hemorrhage (ICH) has generally been limited to global and sensorimotor outcomes. This study examined cognitive outcomes after spontaneous ICH in school‐aged children with serial assessments over 2 years after stroke.

Method

Seven children (age range 6–16y, median 13; six males, one female; 57% white, 43% black) presenting with spontaneous ICH (six arteriovenous malformations) were assessed at 3 months, 12 months, and 24 months after stroke. The Pediatric Stroke Outcome Measure (PSOM) quantified neurological outcome and Wechsler Intelligence Scales measured cognitive outcomes: verbal comprehension, perceptual reasoning, working memory, and processing speed.

Results

PSOM scales showed improved neurological function over the first 12 months, with mild to no sensorimotor deficits and moderate overall deficits at 1‐ and 2‐year follow‐ups (median 2‐year sensorimotor PSOM=0.5, total PSOM=1.5). Changes in cognitive function indicated a different trajectory; verbal comprehension and perceptual reasoning improved over 24 months; low performance was sustained in processing speed and working memory. Age‐normed centile scores decreased between 1‐ and 2‐year follow‐ups for working memory, suggesting emerging deficits compared with peers.

Interpretation

Early and serial cognitive testing in children with ICH is needed to assess cognitive functioning and support children in school as they age and cognitive deficits become more apparent and important for function.

What this paper adds

In children with intracerebral hemorrhage (ICH), motor function improved between 3 months and 24 months.

Improvements in cognitive function were variable between 3 months and 24 months.

Working memory centiles declined, suggesting emerging deficits compared with peers.

Processing speed improved but remained significantly below the 50th centile.

Cognitive impact of ICH may increase with age in children.
Sydney Playground Project: A Cluster‐Randomized Trial to Increase Physical Activity, Play, and Social Skills
Authors: Bundy Anita , Engelen Lina , Wyver Shirley , Tranter Paul , Ragen Jo , Bauman Adrian , Baur Louise , Schiller Wendy , Simpson Judy M. , Niehues Anita N. , Perry Gabrielle , Jessup Glenda , Naughton Geraldine
Published: September 2017

BACKGROUND

We assessed the effectiveness of a simple intervention for increasing children's physical activity, play, perceived competence/social acceptance, and social skills.

METHODS

A cluster‐randomized controlled trial was conducted, in which schools were the clusters. Twelve Sydney (Australia) primary schools were randomly allocated to intervention or control conditions, with 226 children (5‐7 years old) selected randomly to participate. Data were collected at baseline and after 13 weeks. The intervention consisted of introducing recycled materials without an obvious play purpose into school playgrounds and a risk‐reframing workshop for parents and teachers.

RESULTS

Children from the intervention schools increased physical activity and reduced sedentary time while control schools decreased physical activity and increased sedentary time. The intervention yielded increases in total accelerometer counts (β = 9350 counts, 95% CI 3490‐1522, p = .002), minutes of moderate/vigorous physical activity (MVPA) (β = 1.8 min, 95% CI 0.52‐3.12, p = .006), and reductions in sedentary time (β = −2.1 min, 95% CI −3.77‐(−0.51), p = .01). Although the changes in time spent in play and nonplay were not statistically different (p = .08) the effect size (d = .27) indicates clinical significance.

CONCLUSIONS

This intervention was effective for increasing MVPA during recess and demonstrated capacity to improve play opportunities in school playgrounds.
Beyond the Ivory Tower: Labor Market Returns to Greek Membership
Authors: Routon P. Wesley , Walker Jay K.
Published: September 2017

Using a nationally representative sample of college graduates, we estimate the post‐collegiate labor market effects of fraternity and sorority membership during undergraduate tenure. We find that, after controlling for relevant factors, former sorority members’ labor market outcomes are indistinguishable from those of other female college graduates. Former fraternity membership, however, is associated with an increased likelihood of self‐employment of about 10 percentage points and a sizable wage premium. Former fraternity members are indistinguishable from other male college graduates in terms of the probability of employment, historical unemployment, subjective beliefs of personal job security, job satisfaction and satisfaction with earnings.