bluuebunny/crossref_metadata_2025 huggingface dataset:
Engine Mount Design Strategies to Mitigate Linear Vibrations in a Tata Nano
Authors: Phadnis Vrushank S. , Harris Jimmie , Ding Shile , Arambula Chen , Collins Ben , Jeunnette Mark , Winter Amos
Published: November 2018

In 2009, Tata Motors launched the Tata Nano as a low-cost alternative to two and three-wheeled vehicles for India’s growing middle class. However, the Nano failed to meet these expectations as it developed a negative perception amongst Indian consumers partly due to its poor Noise Vibration Harshness (NVH) characteristics. In this paper, we examine strategies to reduce the transmission of linear vibrations from the engine felt inside the cabin. Specifically, it includes analysis of the hardness of damping rubber in the engine mounts as well as geometry of the engine mounts. The results of this analysis suggest that Tata Motors can reduce the vibrations transmitted from the engine by decreasing the hardness of the damping rubber. Additionally, Tata Motors can further reduce the transmitted vibrations by decreasing mount angle. It was found that a reduction in mount angle from 45° to 30° reduced the amplitude of the transmitted vibrations by 23%.
A Theoretical Look at the Impact of Incentives on Design Problem Effort Provision
Authors: Vermillion Sean D. , Malak Richard J.
Published: November 2018

Searching for and selecting among design solutions is not an effortless task. The principle of least effort suggests people seek to minimize the amount of effort they apply towards completing their tasks. In the context of engineering design, it is conceivable that expending more effort on the design problem yields a design solution with greater performance. In this paper, we investigate the impact of incentives on motivating engineering designers to increase the amount of effort they apply to solving design problems. Specifically, we formulate an analytical model of effort provision towards design tasks to compare two incentive structures: a probabilistic incentive and a deterministic incentive. With the probabilistic incentive, a designer’s final reward or penalty is uncertain, e.g. it is uncertain if a proposed design solution will meet requirements. With the deterministic incentive, a designer’s final reward or penalty is tied directly to the quality of the design solution as it is presented, e.g. a proposed design solution meets requirements with a certain probability as the figure of merit and the designer is directly rewarded or penalized on producing a design solution with that figure of merit. We parameterize the proposed analytical model and perform a parameter study to determine which incentive produces a more optimal design solution in the parameter space. Results show that there is no one dominant incentive structure, and the preferred incentive structure depends on how intense the reward or penalty is and how a designer subjectively valuates his effort.
Virtual Reality Applications: Guidelines to Design Natural User Interface
Authors: Regazzoni Daniele , Rizzi Caterina , Vitali Andrea
Published: November 2018

The Natural User Interface (NUI), which permits a simple and consistent user’s interaction, represents a meaningful challenge for developing virtual/augmented reality applications. This paper presents a set of guidelines to design optimal NUI as well as a software framework, named FrameworkVR, which encapsulates the rules of presented guidelines. FrameworkVR allows developing NUI for VR/AR reality applications based on Oculus Rift, Leap Motions device and on the VTK open source library. An example of VR application for prosthesis design developed using FrameworkVR, is also described. Tests have been carried to validate the approach and the designed NUI and results reached so far are presented and discussed.
Understanding Team Personality Evolution in Student Engineering Design Teams Using the Five Factor Model
Authors: Stidham Hallie , Flynn Michelle , Summers Joshua D. , Shuffler Marissa
Published: November 2018

This research explores the role of personalities in engineering design teams in a capstone course using the Five Factor Model of Personality. Specifically, the self and peer assessed personality profiles are across a semester project. After four iterations, the expectation was that peers would be better able to identify their teammates personality traits. Results show that the peer evaluations do change over time. For the factors of Openness, Conscientiousness, and Agreeableness, the agreement between self and peer evaluations increased from Iteration 2 to Iteration 4. The Extraversion factor agreement increased, but not to the point where the peer and self-evaluations did not have statistically significant differences. The agreement between the self and peer evaluations for Neuroticism decreased over time. Extended results, limitations, and future work are also discussed.
Knowledge-Based Artificial Neural Network (KB-ANN) in Engineering: Associating Functional Architecture Modeling, Dimensional Analysis and Causal Graphs to Produce Optimized Topologies for KB-ANNs
Authors: Coatanéa Eric , Tsarkov Vadim , Modi Siddhant , Wu Di , Wang G. Gary , Jafarian Hesam
Published: November 2018

This article documents a study on artificial neural networks (ANNs) applied to the field of engineering and more specifically a study taking advantage of prior domain knowledge of engineering systems to improve the learning capabilities of ANNs by reducing the dimensionality of the ANNs. The proposed approach ultimately leads to training a smaller ANN, offering advantage in training performances such as lower Mean Squared Error, lower cost and faster convergence. The article proposes to associate functional architecture, Pi numbers, and causal graphs and presents a design process to generate optimized knowledge-based ANN (KB-ANN) topologies. The article starts with a literature survey related to ANN and their topologies. Then, an important distinction is made between system behavior centered topologies and ANN centered topologies. The Dimensional Analysis Conceptual Modeling (DACM) framework is introduced as a way of implementing the system behavior centered topology. One case study is analyzed with the goal of defining an optimized KB-ANN topology. The study shows that the KB-ANN topology performed significantly better in term of the size of the required training set than a conventional fully-connected ANN topology. Future work will investigate the application of KB-ANNs to additive manufacturing.
Trajectory Planning for Conformal 3D Printing Using Non-Planar Layers
Authors: Shembekar Aniruddha V. , Yoon Yeo Jung , Kanyuck Alec , Gupta Satyandra K.
Published: November 2018

Additive manufacturing (AM) technologies have been widely used to fabricate 3D objects quickly and cost-effectively. However, building parts consisting of complex geometries with multiple curvatures can be a challenging process for the traditional AM system whose capability is restricted to planar-layered printing. Using 6-DOF industrial robots for AM overcomes this limitation by allowing materials to deposit on non-planar surfaces with desired tool orientation. In this paper, we present collision-free trajectory planning for printing using non-planar deposition. Trajectory parameters subject to surface curvature are properly controlled to avoid any collision with printing surface. We have implemented our approach by using a 6-DOF robot arm. The complex 3D structures with various curvatures were successfully fabricated, while avoiding any failures in joint movement, holding comparable build time and completing with a satisfactory surface finish.
PALEO: Plastically Annealed Lamina Emergent Origami
Authors: Klett Yves
Published: November 2018

Origami is usually folded from a flat sheet of material. Folding mostly works by introduction of plastic deformation into that sheet, resulting in a permanently altered region, viz., the crease. Lamina emergent mechanisms also start by definition from the flat state, but make use of compliant elements to provide mobility by elastic deformation. We introduce a combination of origami tessellations with LEM elements that are annealed in a (partially) collapsed state and retain this shape afterwards, while still offering the elastic deformation potential in the annealed shape. A number of such Plastically Annealed Lamina Emergent Origami structures or PALEOs have been successfully designed and tested.
Task Assignment and Scheduling for Mobile Robot Teams
Authors: Shriyam Shaurya , Gupta Satyandra K.
Published: November 2018

Most complex missions comprise of spatially separated tasks which have to be finished using teams of mobile robots. The main challenges for planning such missions are forming effective coalitions among available robots and assigning them to tasks in such a way that the expected mission completion time is minimized. Our model allows task execution by a fraction of the assigned team even when the rest of the team has not yet arrived at the task location. We also allow tasks to be interrupted and robots of assigned teams to be rescheduled from an unfinished task to another task. We describe five different heuristic algorithms to compute schedules for all robots assigned to the mission. We compare them and analyze the computational performance of the best performing strategy. We also show how to handle uncertainty that may arise during traveling or task execution and then study the effect of varying uncertainty on the minimization of mission completion time.
Sub-Synchronous Shaft Oscillations due to Oil Supply
Authors: Smolík Luboš , Rendl Jan , Stifter Jan , Omasta Milan
Published: November 2018

This paper aims at the modelling and investigation of unstable journal bearing with an emphasis on instabilities such as oil-whirl or further induced oil-whip. For this reason, a test rig for the investigation of these phenomena was built. Geometry, parameters and operating cases of the rig are described in detail in the presented paper. Computational analysis of the test rig was performed using two methods — the finite element method and a multi-body approach. The calculations of pressure distribution in journal bearings were also performed applying two methods — the finite difference method and the finite element method. The results of the analysis are properly introduced and discussed at the end of this paper. The results suggest that a yet unknown sub-synchronous component may appear under specific conditions. The component typically appears at frequency 0.9–0.98 of shaft speed and is likely caused by a location of a bore for oil supply.
A Weighted Least Squares Approach for the Design of Adaptive Aerodynamic Structures Subjected to an Out-Of-Plane Transformation
Authors: Mou Fuzhao , Nejadkhaki Hamid Khakpour , Estes Aaron , Hall John
Published: November 2018

An optimal design framework for adaptive wind turbine blades is presented. A mathematical framework establishes the topology of actuators and material compliance. These parameters are selected to adapt the blade twist distribution into a range of prescribed blade configurations. Our previous work established the ideal twist distribution configurations. The distributions improve the aerodynamic efficiency for a range of wind speeds in which the system operates at partial production. Within this range the nonlinear blade twist distribution changes in relation to the speed. The possibility of producing adaptively compliant structures is becoming increasingly possible with innovative materials and additive manufacturing (AM) processes. Our overarching goal is to create a comprehensive design infrastructure that integrates manufacturing and materials innovation with the complex needs of adaptive structures. This work proposes a method through which the ideal twist distribution can be actualized in structural implementation. The implementation involves a modular blade composed of flexible sections whose twist is modulated by actuators along the blade. Each flexible blade section is composed of two contiguous segments, each with a different torsional stiffness defined by a stiffness ratio. The stiffness variation within each section allows the blade to assume a nonlinear twist distribution when actuated. Errors relative to an ideal twist distribution are minimized by optimizing the stiffness ratios and twist actuator locations. The optimization is completed using a weighted least squares approach that allows the blade designer to bias blade performance toward different operating conditions. A quadratic weighting scheme that penalizes twist errors toward the blade tip is found to result in a higher power coefficient than other weighting schemes.
Optimal Flow Control and Single Split Architecture Exploration for Fluid-Based Thermal Management
Authors: Peddada Satya R. T. , Herber Daniel R. , Pangborn Herschel C. , Alleyne Andrew G. , Allison James T.
Published: November 2018

High-performance cooling is often necessary for thermal management of high power density systems. Both human intuition and vast experience may not be adequate to identify optimal thermal management designs as systems increase in size and complexity. This paper presents a design framework supporting comprehensive exploration of a class of single phase fluid-based cooling architectures. The candidate cooling system architectures are represented using labeled rooted tree graphs. Dynamic models are automatically generated from these trees using a graph-based thermal modeling framework. Optimal performance is determined by solving an appropriate fluid flow control problem, handling temperature constraints in the presence of exogenous heat loads. Rigorous case studies are performed in simulation, with components having variable sets of heat loads and temperature constraints. Results include optimization of thermal endurance for an enumerated set of 4,051 architectures. In addition, cooling system architectures capable of steady-state operation under a given loading are identified.
A Spectral Density Function Approach for Design of Organic Photovoltaic Cells
Authors: Ghumman Umar Farooq , Iyer Akshay , Dulal Rabindra , Wang Aaron , Munshi Joydeep , Chien TeYu , Balasubramanian Ganesh , Chen Wei
Published: November 2018

Organic Photovoltaic Cells (OPVCs), having received significant attention over the last decade, are yet to be established as viable alternatives to conventional solar cells due to their low power conversion efficiency (PCE). Complex interactions of several phenomena coupled with the lack of understanding regarding the influence of fabrication conditions and nanostructure morphology have been major barriers to realizing higher PCE. To this end, we propose a computational microstructural design framework addressing the Processing–Structure–Performance (PSP) linkages for designing the active layer of P3HT:PCBM based OPVCs conforming to bulk heterojunction architecture. The framework pivots around the Spectral Density Function (SDF), a frequency space microstructure characterization and reconstruction methodology, for microstructure design representation. Nanostructure images obtained by novel Scanning Tunneling Microscopy are used to validate the applicability of SDF for representing active layer morphology in OPVCs. SDF enables a low dimensional microstructure representation that is crucial in formulating a parametrized microstructure optimization scheme. A level-cut Gaussian Random Field (governed by SDF) technique is used to generate reconstructions that serve as Representative Volume Elements (RVEs) for structure-performance simulations. A novel structure-performance simulation approach is developed using physics-based performance metric, Incident Photon to Converted Electron (IPCE) ratio, to account for the impact of microstructural features on OPVC performance. Finally, an SDF based computational IPCE optimization study using metamodels created using design of computer experiments over three design variables results in 36.75% increase in IPCE, underlining the efficacy of proposed design framework.
Kinetostatic Analysis of a Simple Cable-Driven Parallel Crane
Authors: Lessanibahri Saman , Cardou Philippe , Caro Stéphane
Published: November 2018

This paper introduces the concept of a new planar Cable-Driven Parallel Crane (CDPC) for lifting and carrying payloads with a moving hoist mechanism connected in parallel to the ceiling. In contrast to bridge-crane, CDPC is inexpensive and practicable for diverse tasks with simple assembly setup. The hoist mechanism is an under-constrained moving-platform articulated through a bi-actuated cable circuit, namely, a cable loop. The hoist is connected to a suspended moving-platform with four degrees of freedom. The power is transmitted directly from the motors fixed on frames to the hoist through the cable loop. Therefore, the dynamic performance of the robot is increased due to lower inertia of the moving-platform. However, the moving-platform undergoes some parasitic inclinations because of the cable loop. This paper investigates the parasitic inclination and its effect on the positioning of the payload. The workspace of the CDPC is studied in terms of static equilibrium. Moreover, the geometrico-static and elasto-static models of the CDPC are presented.
Second-Order Perturbation Analysis of In-Plane Blade-Hub Dynamics of Horizontal-Axis Wind Turbines
Authors: Sapmaz Ayse , Feeny Brian F.
Published: November 2018

This paper deals with a second-order perturbation analysis of the in-plane dynamic responses of both tuned and mistuned three-blade-hub horizontal-axis wind-turbine equations. The blades are under effect of gravitational and cyclic aerodynamics forces and centrifugal forces. Although the blades and hub equations are coupled, they can be decoupled by changing the independent variable from time to rotor angle and by using a small parameter approximation. A second-order method of multiple scales is applied in the rotor-angle domain to analyze in-plane blade-hub dynamics. A superharmonic resonance case at one third the natural frequency was revealed. This resonance case was not captured by a first-order perturbation expansion. The relationship between response amplitude and frequency is studied. The effect of blade mistuning on the coupled blade-hub dynamics are taken into account.
Joint Application of Spectral Kurtosis and Velocity Synchrosqueezing Transform for Fault Diagnosis of Ball Bearing Under Nonstationary Conditions
Authors: Guan Yunpeng , Liang Ming , Necsulescu Dan-Sorin
Published: November 2018

Time-frequency method is a good tool to analysis the vibration signal for condition monitoring of rotational machinery under non-stationary conditions. However, the fault feature of bearing cannot be directly revealed using the time-frequency method, because the fault causes complex modulation of resonance frequency. To resolve this problem, this paper proposes a joint application of Spectral Kurtosis (SK) and Velocity Synchrosqueezing Transform (VST). The vibration is firstly processed by spectral kurtosis method to extract the impulse features of the signal. After this, amplitude demodulation techniques are applied to obtain the impulse envelope. Finally the VST is applied to reveal the time-frequency feature of the envelope signal. The fault, if any, can be diagnosed by identifying the uncovered signal components. The effectiveness of the proposed method is validated using experimental signals collected under non-stationary condition.
From Conventional to Additive Manufacturing: Determining Component Fabrication Feasibility
Authors: Ghiasian Seyedeh Elaheh , Jaiswal Prakhar , Rai Rahul , Lewis Kemper
Published: November 2018

The use of additive manufacturing (AM) for fabricating industrial grade components has increased significantly in recent years. Numerous industrial entities are looking to leverage new AM techniques to enable fabrication of components that were typically manufactured previously using conventional manufacturing techniques such as subtractive manufacturing or casting. Therefore, it is becoming increasingly important to be able to rigorously evaluate the technical and economic feasibility of additively manufacturing a component relative to conventional alternatives. In order to support this evaluation, this paper presents a framework that investigates fabrication feasibility for AM from three perspectives: geometric evaluation, build orientation/support generation, and resources necessary (i.e., cost and time). The core functionality of the framework is enabled on voxelized model representation, discrete and binary formats of 3D continuous objects. AM fabrication feasibility analysis is applied to 34 various parts representing a wide range of manifolds and valves manufactured using conventional manufacturing techniques, components commonly found in the aerospace industry. Results obtained illustrate the capability and generalizability of the framework to analyze intricate geometries and provide a primary assessment for the feasibility of the AM process.
Patterns of Cortical Activation When Using Concept Generation Techniques of Brainstorming, Morphological Analysis, and TRIZ
Authors: Shealy Tripp , Hu Mo , Gero John
Published: November 2018

This paper presents the results of an experimental study comparing cortical activation in the brain when generating solutions using brainstorming, morphological analysis, and TRIZ. Twelve engineering students were given the same three design tasks, respectively, using the three solution generation techniques. Students generated solutions while change in oxygenated blood along the prefrontal cortex (PFC) was measured using functional near-infrared spectroscopy. The results show that generating solutions using brainstorming, morphological analysis, and TRIZ leads to differences in cortical activation, specifically along the region of the brain associated with spatial working memory, cognitive flexibility, and abstract reasoning, called the left dorsolateral prefrontal cortex (left DLPFC). Brainstorming evokes a high average blood oxygenation level dependent (BOLD) response in the left DLPFC early during the solution generation process but this high response is not sustained. In comparison, morphological analysis and TRIZ evoke multiple high average BOLD responses across the solution generation process. Not only was the high average BOLD response sustained but the density of network coordination among brain regions across the PFC was greater for morphological analysis and TRIZ. Higher density is a proxy for higher cognitive effort. The brain regions most central to coordination also varied. During brainstorming the right hemisphere, in a region associated with memory encoding (right PFC), was most activated. During morphological analysis, the left hemisphere, the left DLPFC was most activated. During TRIZ, both the middle and left hemisphere included regions of high activation. These results indicate neuro-cognitive differences of activation patterns, cognitive effort over time, and brain regions central for coordination when using these three concept generation techniques. Future research can begin to explore neuro-cognitive differences as a result of these techniques over multiple uses and the effects of design education.
Robot Evidence Based Search for a Dynamic User in an Indoor Environment
Authors: Lin Shayne , Nejat Goldie
Published: November 2018

In this paper we present the development of an evidence-based search planner for a mobile assistive robot to autonomously search for a dynamic person in a multi-room home environment in order to provide assistance. We solve the dynamic person search problem by uniquely considering evidence of household objects along with a user spatial-temporal model to increase the probability of finding the user. Our planner utilizes a Partially Observable Markov Decision Process (POMDP) to plan optimal robot search paths in the environment as the user and evidence locations are partially observable. Extensive simulated experiments in a home environment were conducted to compare our proposed evidence-based search approach with 1) a search technique without prior user information, and 2) a search technique that only uses a user model. The results show that our proposed search technique has higher success rates for finding the user and is more robust to the dynamic behaviors of the user.
A Needs Assessment for Physical Activity Programming Based on the Transtheoretical Model
Authors: Mettling Shannon , Lee Jung-Min , Blount Ashley , Dinkel Danae
Published: November 2018

The purpose of this study was to (a) examine differences between type of physical activity (PA), college, gender, and body mass index (BMI); and (b) explore the needs of college students in regard to PA programming using the Transtheoretical Model (TTM). Students at a Midwestern university completed a PA programming questionnaire and the Stages of Change questionnaire. After exclusions, 535 questionnaires were analyzed. Of those surveyed, 45.6% met aerobic PA guidelines, 38.5% met muscle-strengthening guidelines, half of the students were of normal weight, and the other half were overweight or obese. Males participated in more PA than females in both categories. The greatest percentage of students were in the maintenance stage of the TTM (38.1%). In regard to PA programming, the largest percentage of students wanted more variety in times and styles for cardio and strength classes. Future campus recreation professionals could consider utilizing a similar survey to identify demographics and stage of change to better design PA programs.
A swarm of slippery micropropellers penetrates the vitreous body of the eye
Authors: Wu Zhiguang , Troll Jonas , Jeong Hyeon-Ho , Wei Qiang , Stang Marius , Ziemssen Focke , Wang Zegao , Dong Mingdong , Schnichels Sven , Qiu Tian , Fischer Peer
Published: November 2018

A swarm of microrobots propels through the vitreous humor of the eye and reaches a small targeted spot on the retina.
Discovery of log-periodic oscillations in ultraquantum topological materials
Authors: Wang Huichao , Liu Haiwen , Li Yanan , Liu Yongjie , Wang Junfeng , Liu Jun , Dai Ji-Yan , Wang Yong , Li Liang , Yan Jiaqiang , Mandrus David , Xie X. C. , Wang Jian
Published: November 2018

Quantum oscillations are usually the manifestation of the underlying physical nature in condensed matter systems. Here, we report a new type of log-periodic quantum oscillations in ultraquantum three-dimensional topological materials. Beyond the quantum limit (QL), we observe the log-periodic oscillations involving up to five oscillating cycles (five peaks and five dips) on the magnetoresistance of high-quality single-crystal ZrTe
5
, virtually showing the clearest feature of discrete scale invariance (DSI). Further, theoretical analyses show that the two-body quasi-bound states can be responsible for the DSI feature. Our work provides a new perspective on the ground state of topological materials beyond the QL.
One publisher, more than 7000 retractions
Authors: McCook Alison
Published: November 2018

Thousands of abstracts of conference presentations, most by authors in China, were declared flawed.
Soft magnetic materials for a sustainable and electrified world
Authors: Silveyra Josefina M. , Ferrara Enzo , Huber Dale L. , Monson Todd C.
Published: November 2018

Faster switching for soft magnets

The most familiar magnets are permanent magnets like the ones on a refrigerator door. However, for applications in transformers and motors, soft magnets that can rapidly switch their magnetization in response to a magnetic field are used. In electronics, wide bandgap semiconductors such as silicon carbide will allow power conversion electronics and motor controllers to operate more efficiently, but soft magnets must be developed that can respond at higher frequencies. Silveyra
et al.
review the development of current soft magnetic materials and opportunities for improving their performance in high-frequency operation. Materials being explored include soft ferrites, amorphous and nanocrystalline alloys, and powder cores or soft magnetic composites.

Science
, this issue p.
eaao0195
Efficient access to unprotected primary amines by iron-catalyzed aminochlorination of alkenes
Authors: Legnani Luca , Prina-Cerai Gabriele , Delcaillau Tristan , Willems Suzanne , Morandi Bill
Published: November 2018

Salt and iron ease the way to amines

Adding nitrogen to carbon compounds is often a laborious process. The nitrogen typically needs protection to prevent undesired reactivity, and the protecting groups can be hard to remove afterward. Legnani
et al.
report a versatile method to add unadorned NH
2
from a hydroxylamine derivative directly to a double-bonded carbon center. A simple iron catalyst manipulates chloride from table salt onto the adjacent carbon through a radical mechanism, where it is poised for a wide variety of further functionalization options.

Science
, this issue p.
434
Trypping up antigenic variation in sleeping sickness
Authors: Griffin Gabriel K.
Published: November 2018

Histone variants ensure proper genome partitioning in trypanosomes to restrict antigenic variation.
Laboratory Methods in Molecular Epidemiology: Bacterial Infections
Authors: Riley Lee W.
Published: November 2018

In infectious disease epidemiology, the laboratory plays a critical role in diagnosis, outbreak investigations, surveillance, and characterizing biologic properties of microbes associated with their transmissibility, resistance to anti-infectives, and pathogenesis. The laboratory can inform and refine epidemiologic study design and data analyses. In public health, the laboratory functions to assess effect of an intervention. In addition to research laboratories, the new-generation molecular microbiology technology has been adapted into clinical and public health laboratories to simplify, accelerate, and make precise detection and identification of infectious disease pathogens. This technology is also being applied to subtype microbes to conduct investigations that advance our knowledge of epidemiology of old and emerging infectious diseases. Because of the recent explosive progress in molecular microbiology technology and the vast amount of data generated from the applications of this technology, thisMicrobiology SpectrumCurated Collection: Advances in Molecular Epidemiology of Infectious Diseases describes these methods separately for bacteria, viruses, and parasites. This review discusses past and current advancements made in laboratory methods used to conduct epidemiologic studies of bacterial infections. It describes methods used to subtype bacterial organisms based on molecular microbiology techniques, following a discussion on what is meant by bacterial “species” and “clones.” Discussions on past and new genotyping tests applied to epidemiologic investigations focus on tests that compare electrophoretic band patterns, hybridization matrices, and nucleic acid sequences. Applications of these genotyping tests to address epidemiologic issues are detailed elsewhere in other reviews of this series.*

This article is part of a curated collection.
Fever duration during treated urinary tract infections and development of permanent renal lesions
Authors: Karavanaki Kyriaki , Koufadaki Athina Maria , Soldatou Alexandra , Tsentidis Charalambos , Sourani Maria , Gougourelas Dimitris , Haliotis Fotis Angelos , Stefanidis Constantinos J
Published: November 2018

Objective

To assess the effect of the duration of fever after the initiation of treatment (FAT) of febrile urinary tract infections (UTI) on the development of permanent renal lesions based on dimercaptosuccinic acid (DMSA) scintigraphy findings. To evaluate the FAT contribution to permanent renal lesion formation in relation to fever before treatment initiation (FBT), the presence of vesicourinary reflux (VUR), age and severity of infection.

Methods

The inpatient records of 148 children (median age: 2.4 months (11 days to 24 months)) with a first episode of UTI during a 3-year period were analysed. DMSA findings, and clinical and laboratory parameters were evaluated.

Results

Among the study population, 34/148 (22.97%) children had permanent renal lesions on the DMSA scan 6 months after a single episode of UTI. Twenty-three children (15.5%) had mild, 10 (6.7%) had moderate and 1 (0.6%) child had severe lesions on the DMSA. FAT prolongation >/48 hours was associated with older age (p=0.01) and increased absolute neutrophil count (p=0.042). The likelihood of lesions was significantly increased when FAT was ≥48 hours (R2=0.043, p=0.021). On multiple regression analysis, with the addition of FBT>/72 hours (0.022), the presence of VUR (p<0.001), C-reactive protein (p=0.027) and age (p=0.031), the effect of FAT on lesion development disappeared (p=0.15).

Conclusions

Prolongation of FAT≥48 hours of febrile UTI in children <2 years significantly contributes to the development of permanent renal lesions. However, delay in treatment initiation >/72 hours, the presence of VUR, older age and infection severity seem to be more significant predictors of the development of renal lesions.
General practitioners’ perspectives on the prevention of cardiovascular disease: systematic review and thematic synthesis of qualitative studies
Authors: Ju Irene , Banks Emily , Calabria Bianca , Ju Angela , Agostino Jason , Korda Rosemary J , Usherwood Tim , Manera Karine , Hanson Camilla S , Craig Jonathan C , Tong Allison
Published: November 2018

Objective

Cardiovascular disease (CVD) is a leading cause of morbidity and mortality globally, and prevention of CVD is a public health priority. This paper aims to describe the perspectives of general practitioners (GPs) on the prevention of CVD across different contexts.

Design

Systematic review and thematic synthesis of qualitative studies using the Enhancing Transparency of Reporting the Synthesis of Qualitative research (ENTREQ) framework.

Data sources

MEDLINE, Embase, PsycINFO and CINAHL from database inception to April 2018.

Eligibility criteria for selecting studies

We included qualitative studies on the perspectives of GPs on CVD prevention.

Data extraction and synthesis

We used HyperRESEARCH to code the primary papers and identified themes.

Results

We selected 34 studies involving 1223 participants across nine countries. We identified six themes: defining own primary role (duty to prescribe medication, refraining from risking patients’ lives, mediating between patients and specialists, delegating responsibility to patients, providing holistic care); trusting external expertise (depending on credible evidence and opinion, entrusting care to other health professionals, integrating into patient context); motivating behavioural change for prevention (highlighting tangible improvements, negotiating patient acceptance, enabling autonomy and empowerment, harnessing the power of fear, disappointment with futility of advice); recognising and accepting patient capacities (ascertaining patient’s drive for lifestyle change, conceding to ingrained habits, prioritising urgent comorbidities, tailoring to patient environment and literacy); avoiding overmedicalisation (averting long-term dependence on medications, preventing a false sense of security, minimising stress of sickness) and minimising economic burdens (avoiding unjustified costs to patients, delivering practice within budget, alleviating healthcare expenses).

Conclusions

GPs sought to empower patients to prevent CVD, but consideration of patients’ individual factors was challenging. Community-based strategies for assessing CVD risk involving other health professionals, and decision aids that address the individuality of the patient’s health and environment, may support GPs in their decisions regarding CVD prevention.
Indwelling urinary catheters, aortic valve treatment and delirium: a prospective cohort study
Authors: Eide Leslie SP , Ranhoff Anette H , Lauck Sandra , Fridlund Bengt , Haaverstad Rune , Hufthammer Karl Ove , Kuiper Karel K J , Nordrehaug Jan Erik , Norekvål Tone Merete
Published: November 2018

Objectives

To determine whether an association exists between delirium and length of time indwelling urine catheters (IUC) are used in octogenarian patients treated with surgical aortic valve treatment (SAVR) or transcatheter aortic valve implantation (TAVI).

Design

Prospective cohort study.

Setting

Tertiary university hospital covering the western region of Norway.

Participants

Octogenarian patients undergoing elective SAVR or TAVI and willing to participate in the study were eligible. Patients unable to speak Norwegian were excluded. Between 2011 and 2013, 143 consecutive patients were included, and data from 136 of them are presented.

Primary outcome

Delirium.

Results

Logistic regression analysis shows that lower cognitive function was positively associated with delirium (OR 0.86, CI 0.74 to 0.99, p=0.047). Besides, the interaction term in the model shows that IUC use and delirium differed between SAVR and TAVI patients (p=0.04). The difference corresponded to a weaker association between hours of IUC use and delirium for SAVR (OR 1.01, CI: 0.99 to 1.03, p=0.54) compared with that for TAVI (OR 1.04, CI: 1.01 to 1.08, p=0.004).

Conclusions

The association between IUC use and delirium is stronger for octogenarian patients treated with TAVI than for patients who received SAVR. Our results revealed a previously unknown association between the number of hours an IUC is used and postoperative delirium in octogenarian patients treated with TAVI.
Protocol for a feasibility and acceptability study using a brief ACT-based intervention for people from Southwest Wales who live with persistent pain
Authors: Saracutu Madalina , Edwards Darren J , Davies Helen , Rance Jaynie
Published: November 2018

Introduction

Persistent pain affects a large percentage of the UK population and its burden has wide ramifications that affect physical, psychological, socioeconomic and occupational status. Pain has a significant impact on people’s well-being and quality of life. Some of the most common comorbidities found in this population are depression and anxiety and also maladaptive behaviours such as fear avoidance and catastrophising.

Methods and analysis

This is a protocol for a study assessing the feasibility and acceptability of a novel Acceptance and Commitment Therapy (ACT)-based intervention for people from Southwest Wales who live with persistent pain. A group of 12 participants will be recruited through the Health and Wellbeing Academy (Swansea University). After being referred by an Osteopath, and attending a brief meeting with the researcher, the participants will take part in six sessions over six consecutive weeks. ‘A Mindful Act’ is an ACT-based group programme aiming to teach people how to develop more acceptance and self-compassion, be more mindful and clarify personal values in order to live a more rich and meaningful life. The main outcomes will include the feasibility of the recruitment process and the measurement tools, the acceptability of the intervention for both the participants and the Osteopaths and the adherence to the programme. In order to measure acceptability of the intervention, qualitative interviews will be conducted to provide an insight into peoples’ experiences of taking part. Data will be analysed using Thematic Analysis, with the use of NVIVO 10. In addition, quantitative data will be collected at baseline, on completion of the programme and at 1 month and 3 months follow-up to reveal any differences in psychological flexibility, depression, anxiety, fear avoidance and general health status. The findings will help enhance the intervention by making appropriate modifications to the processes and procedures involved, following the recommendations made by the Medical Research Council framework. A larger scale study is envisaged to follow, in order to investigate the full effectiveness and cost-effectiveness of ‘A Mindful Act’.

Ethics and dissemination

This study was approved by the College of Human and Health Sciences Research Ethics Committee at Swansea University in December 2017. The findings will be disseminated through various means including: the first author’s PhD thesis, peer-reviewed journals as well as well as national and international conferences and public events.
Trial of intraoperative cell salvage versus transfusion in ovarian cancer (TIC TOC): protocol for a randomised controlled feasibility study
Authors: Galaal Khadra , Lopes Alberto , Pritchard Colin , Barton Andrew , Wingham Jennifer , Marques Elsa M R , Faulds John , Palmer Joanne , Vickery Patricia Jane , Ralph Catherine , Ferreira Nicole , Ewings Paul
Published: November 2018

Introduction

Ovarian cancer is the leading cause of death from gynaecological cancer, with more than 7000 new cases registered in the UK in 2014. In patients suitable for surgery, the National Institute of Health and Care Excellence guidance for treatment recommends surgical resection of all macroscopic tumour, followed by chemotherapy. The surgical procedure can be extensive and associated with substantial blood loss which is conventionally replaced with a donor blood transfusion. While often necessary and lifesaving, the use of donor blood is associated with increased risks of complications and adverse surgical outcomes. Intraoperative cell salvage (ICS) is a blood conservation strategy in which red cells collected from blood lost during surgery are returned to the patient thus minimising the use of donor blood. This is the protocol for a feasibility randomised controlled trial with an embedded qualitative study and feasibility economic evaluation. If feasible, a later definitive trial will test the effectiveness and cost-effectiveness of ICS reinfusion versus donor blood transfusion in ovarian cancer surgery.

Methods and analysis

Sixty adult women scheduled for primary or interval ovarian cancer surgery at participating UK National Health Service Trusts will be recruited and individually randomised in a 1:1 ratio to receive ICS reinfusion or donor blood (as required) during surgery. Participants will be followed up by telephone at 30 days postoperatively for adverse events monitoring and by postal questionnaire at 6 weeks and 3 monthly thereafter, to capture quality of life and resource use data. Qualitative interviews will capture participants’ and clinicians’ experiences of the study.

Ethics and dissemination

This study has been granted ethical approval by the South West–Exeter Research Ethics Committee (ref: 16/SW/0256). Results will be disseminated via peer-reviewed publications and will inform the design of a larger trial.

Trial registration number

ISRCTN19517317.
Better care: reducing length of stay and bed occupancy on an older adult psychiatric ward
Authors: Adlington Katherine , Brown Juliette , Ralph Laura , Clarke Alan , Bhoyroo Tim , Henderson Michael , Boora Farai , Aurelio Marco , Fawzi Waleed
Published: November 2018

Background

Length of stay and bed occupancy are important indicators of quality of care. Admissions are longer on older adult psychiatric wards as a result of physical comorbidity and complex care needs. The recommended bed occupancy is 85%; levels of 95% or higher are associated with violent incidents on inpatient wards.

Methods

We aimed to reduce length of stay and bed occupancy on Leadenhall ward, a functional older adult psychiatric ward serving a population of just under 40 000 older adults in two of the most deprived areas of the UK.

At baseline in October 2015, the average length of stay was 47 days, and bed occupancy was at 77%. We approached the problem using quality improvement methods, established a project team and proceeded to test a number of changes over time in line with the driver diagram we produced.

Results

In 12 months, length of stay was reduced from an average 47 to an average 30 days and bed occupancy from 77% to 54%.

At the end of 2016, the closure of some beds effected this calculation and we added an additional outcome measure of occupied bed days (OBD) better to assess the impact of the work. OBD data show a decrease over the course of the project from 251 to 194 bed days (a reduction of 23%).

Conclusion

The most effective interventions to address length of stay and bed occupancy on an older adult functional mental health ward were the daily management round and the high-level management focus on longer-stay patients. The work depended on an effective community team and on the support of the quality improvement programme in the trust, which have led to sustained improvements.
Improving resuscitation decisions: a trust-wide initiative
Authors: Fadel Michael G , Parekh Krishan , Hayden Paul , Krishnan Priya
Published: November 2018

Introduction

Treatment escalation plans (TEPs) are important to ensure that every patient has their ceiling of care discussed and documented formally. At Medway Foundation Trust, we introduced TEP forms in September 2016 which are to be completed by the relevant consultant within 24 hours of admission.

Aims and methods

To evaluate whether TEP forms had been effective at improving escalation planning and whether they had a subsequent impact in do not attempt cardiopulmonary resuscitation (DNACPR) decision-making. We carried out three plan-do-study-act cycles over a 2-year period across 100 patients in medicine and surgery.

Results

TEP forms were initially found in 66% (66/100) of the patient notes and 34% (34/100) were completed appropriately. There was a 13% relative improvement in resuscitation decision-making, since the introduction of the TEP forms from November 2015 to January 2017. There was also a 12% reduction in inappropriate referrals to critical care during the same period. We decided to revise the TEP form through extensive collaboration and educate all staff members about the importance of escalation planning. This has led to an improvement in TEP discussion and documentation across the entire trust.

Conclusion

TEPs can be an effective way of considering and communicating ceilings of care. They should encourage doctors to consider DNACPR decisions for patients who otherwise would not have been considered, and therefore may help reduce inappropriate referrals to critical care. The higher completion rates of the new form and increased clarity among staff regarding escalation planning should lead to an improvement in patient safety outcomes and communication between all patients and staff members. We believe it would be feasible to implement our user-friendly TEP form across other National Health Service organisations in order to develop a universal TEP form.