bluuebunny/crossref_metadata_2025 huggingface dataset:
Using Experimental Fluid Dynamics and Computational Fluid Dynamics for Evaluating Periodic Mixing
Authors: Bamberger Judith Ann , Pease Leonard F. , Recknagle Kurtis P. , Enderlin Carl W. , Minette Michael J.
Published: January 2019

Periodic mixing using pulse jet mixers is being developed and applied for processing unique slurries of radioactive waste that depending upon the slurry properties may possess either Newtonian or non-Newtonian characteristics. To investigate the performance of these mixing systems, scaled experimental fluid dynamics (EFD) experiments have been conducted and in addition, for certain investigations, computational fluid dynamics (CFD) simulations have been applied. The purpose of this paper is to describe the periodic mixing processes, elaborate regarding the types of scaled experiments that were conducted, and present examples of computational investigations conducted to further define the mixing system performance. The experimental investigations showed the ability to track visual metrics such as cloud height and cavern size. The computational investigations demonstrated the ability to model full-scale experiments with Newtonian slurries.
Dynamic Characteristics of Resonant Beams With Passive Thermal Stress Regulators
Authors: Kellar Tyler , Hassanpour Pezhman
Published: January 2019

This paper addresses the dynamic characteristics of a beam with a particular elastic boundary condition. In this elastic boundary condition, the lateral and angular displacements of the beam are coupled through the elastic constraints. The dynamic characteristic, namely natural frequencies and mode shapes of vibrations are frequently encountered in the design and modeling of resonant micro-structures. The governing equations of motion of the beam is derived using Euler-Bernoulli beam theory considering the elastic coupling between the transverse and rotational displacements of the beam’s end. The characteristic equation for the natural frequencies and mode shapes of vibration is derived by applying the method of separation of variables to the governing partial differential equation of motion. The natural frequencies and mode shapes of the system are derived for various combinations of compliance values of the elastic support and are compared with those of several special cases, namely clamped-free, clamped-guided, clamped-pinned and clamped-clamped beams.
A Reflection of a Pedagogic Approach in an Engineering Course
Authors: Ferreira Manuel E. , Ferreira João , Leão Celina P.
Published: January 2019

This paper focused the subject of engineering education for Energy Conversion, last year of the the Integrated Master in Mechanical Engineering Master Course of University of Minho. This curricular unit focus on the fossil fuel resources and combustion. Previous study, carried out by one of the authors, show that a final project can be used as a lever for students’ awareness and to understand the renewable energy sources. Also, it allowed students to identify several challenges to be addressed in the future. The present study goes further and the aim behind it is to understand students’ concerns in this area. To do so, both quantitative and qualitative approaches were used. Quantitative approach, by taking account of the results of an inquiry questionnaire applied to obtain students’ perceptions towards the implementation of this teaching approach and assessment methodology. Qualitative approach, to complement the quantitative findings, using both written project report and oral presentations, to perceive students’ awareness, knowledge and sustainability in Energy and Environment topic. So, it will be possible to understand which topic was preferred, why this particular topic was chosen, how the topic was addressed, if students identified challenges and opportunities, and learn from developing this projects, among others.
An Internet-of-Things Based Framework for Collaborative Cyber Physical Tasks in Micro Assembly
Authors: Cecil J. , Cecil-Xavier Aaron , Albuhamood S.
Published: January 2019

The emergence of Internet-of-Things (IoT) and Cyber Physical Systems (CPS) based principles and technologies holds the potential to support collaborative manufacturing. In this paper, the focus of the research is the design of an Internet of Things (IoT) based Cyber Physical approach for the assembly of micro devices. Micro Devices Assembly (MDA) is an emerging domain involving the assembly of micron sized objects and devices. An advanced collaborative Cyber Physical framework comprising of cyber and physical components linked using the Next Generation Internet has been developed to accomplish a set of MDA life cycle activities which include assembly planning, path planning, Virtual Reality (VR) based assembly analysis, command generation and physical assembly. Genetic algorithm and modified Insertion algorithm-based methods have been proposed to support assembly planning activities. Advanced VR based environments have been designed to support assembly analysis where plans can be proposed, compared and validated. The potential of next generation Global Environment for Network Innovation (GENI) networking technologies has also been explored to support distributed collaborations involving VR based environments. An IoT Test Bed has been built to demonstrate the feasibility of the framework proposed to assemble micro designs. This is the first reported implementation of a comprehensive IoT based cyber physical system in advanced manufacturing.
Pilot Scale Experimental Study of Slug Flow Phenomena Using PID Control
Authors: McClung Jeffery W. , Schmidt Daniel S. , Staal Derek W. , Behl Mark V. , Tyagi Mayank
Published: January 2019

Slug flow is a major problem to the structural integrity and production equipment in offshore production platforms. Pressure oscillations due to the alternation of liquid and gas phases in slug flow regime can cause fatigue on the structural components of the platform. Also, the intermittent high flow rates can cause adverse effects on the production equipment.

A 28-foot pilot scale model was constructed to simulate the riser on offshore platforms. Three pressure sensors were attached to the model to monitor and record pressures in the riser during operations. A PID control strategy was utilized to regulate the pressure oscillations in the system by use of a linear actuated valve. Similarity between the pressure signals in the pilot scale model is qualitative when compared to actual pressures observed in an offshore riser system. A MATLAB® GUI was designed to allow for manipulation of the valve and allow for instant graphing of data for real time visualization of the pressure signals.

Pressure oscillations during slug flow with “no control” vary greatly and result in natural vibrations of the designed system. By pinching down on the choke valve to a designated opening, the back pressure in the riser increased, thereby slowing down the liquid slugs. However, an increase in the magnitude of the higher frequency oscillations can have adverse effects on the system. With the implementation of an active control, such as a linear actuated valve, a better control of back pressure on the riser and reduction in the magnitude of the higher frequency oscillations on the system is achieved.
The Improved Model of Particle Shape Prediction Considering the Choke-Level Effect for Cone Crusher
Authors: Wei Zhang , Jixin Wang , Xiangjun Yu
Published: January 2019

The choke-level is one of the key factors that influence the falling process of the granular materials which is closely related to the crushing efficiency in the cone crusher. In this paper the motion characteristics of the particles near the choke-level have been analyzed and the phenomenon of single particle breakage below the choke level is pointed out. Based on the multi-zone method, an improved particle shape prediction model is established. In this model, the compound breaking behavior which includes the single particle breakage under the choke-level effect and the inter-particles breakage under the fill-feed, the transformation of particle shape and the particle size distribution in each crushing zone are considered. Tests on the PYG-B1735 cone crusher are conducted in order to validate the improved model. The improved model provides a theoretical foundation for the productivity estimation and the performance optimization.
Thermal Conductivity of Colloidal Suspensions of Jet Fuel and Carbon-Based Nanoparticles and its Effect on Evaporation Rate
Authors: Ghamari Mohsen , Aboalhamayie Ahmed
Published: January 2019

Recent studies have shown that addition of nano-sized particles to liquid fuels could significantly enhance major combustion characteristics such as burning rate and ignition delay. Colloidal suspensions are known to have enhanced optical properties and thermal conductivity compared to neat liquids; however, in the case of colloidal fuels, the main mechanism responsible for such enhanced properties is not well understood. To better understand these phenomena, colloidal suspensions of jet fuel and different types of carbon-based nanomaterials (carbon nanoparticles, multi-walled carbon nanotubes, and graphene nanoplatelets) prepared at different particle loadings were experimentally tested for their thermal conductivities. Colloidal suspensions of nanotubes showed higher conductivity compared to that of graphene and nanoparticle. This could justify higher burning rate of these fuels. Furthermore, and to differentiate between the effects of thermal conduction and radiation, droplet evaporations tests were carried out on colloidal suspensions of carbon nanoparticle under forced convection and in the absence of any radiation source. It was found that the presence of nanoparticle in jet fuel initially increases evaporation rate. However, a reduction in evaporation rate was observed at higher concentration as a result of particles agglomeration.
Laser Foaming of Polyetherimide (PEI)
Authors: Kakumanu Venkateshwarlu , Srinivas Sundarram Sriharsha
Published: January 2019

Polyetherimide micro and nano foams find applications in structural, chemical, thermal, and biological fields. Polyetherimide micro and nano foams have been fabricated using variety of approaches that includes gas foaming and solvent casting. These techniques however result in foams either with very low thickness or whose porous region is embedded with a solid outer layer severely restricting their use for biomedical applications especially as scaffolds for tissue engineering. In this study, a novel solvent free approach of fabricating bulk polyetherimide foams using laser irradiation of samples saturated with carbon dioxide, for applications in the biomedical field is presented. The effects of processing parameters namely laser head travel speed and power on the resulting morphologies are analyzed using microscopy techniques. The scanning electron microscopy images show that pores with an average size of 3.5 microns are generated on a conical surface across the cross section with interior pores in the hundreds of nanometer range. This study shows that laser foaming can be successfully used to fabricate skinless polyetherimide micro and nano foams with a combination of medium power and low speed resulting in ideal morphology.
Development of Processing Map for Superplastic Deformation of Ti-6Al-4V Alloy
Authors: Wahed Mohd Abdul , Gupta Amit Kumar , Kotkunde Nitin Ramesh , Singh Swadesh Kumar
Published: January 2019

A processing map plays a major role in indicating safe and failure regions of a process conducted in a hot working regime. It also shows the response of a material, by indicating changes in the microstructural evolution through temperature. In the present study, a processing map has been developed depending on the flow stress data of Ti-6Al-4V alloy sheet in a strain rate range of 10−2 /s to 10−4 /s and over a temperature range of 700°C to 900°C in order to identify the presence of superplasticity region. The flow stress data have been acquired on the basis of temperature, strain and strain rate by conducting hot uniaxial tensile tests. Based on this, a power dissipation map is obtained to show the percentage of efficiency, as it is directly related to the amount of internal entropy produced. In addition, an instability map is also obtained, as it identifies the flow instability that are to be avoided during hot working process. Finally, a processing map has been established by overlaying instability map on efficiency map. The results clearly reveal that the superplastic deformation occurs within a temperature range of 750°C to 900°C at a strain rate of 10−4 /s, without any flow instability in this region.
Layout of Phase Change Materials in a Thermal Energy Storage System
Authors: Khan Habeeb Ur Rahman , Aldoss Taha K. , Rahman Muhammad M.
Published: January 2019

The objective of this work is to investigate the performance of a thermal energy storage system using multiple phase change materials (PCMs). This study is based on latent heat thermal energy storage. Three phase change materials namely, Potassium Hydroxide (KOH), Potassium Nitrate (KNO3), and Sodium Nitrate (NaNO3) have been selected for this study. These PCMs have been chosen because of their inherent thermal stability, high melting point, high latent heat of fusion per unit mass, relatively high thermal conductivity, high specific heat, non-flammable properties, and availability. In this work, the performance of the thermal energy storage system is analyzed by evaluating key parameters such as liquid fraction and the amount of energy stored and extracted during charging and discharging respectively. Two types of PCM layouts, uniform and cascaded, have been employed. In case of uniform PCM layout, only one type of PCM is used at a time throughout the bed. In case of cascaded PCM layout, multiple PCMs are used at a time throughout the bed. The cascaded layout further has two types of arrangement. The first type of arrangement is the slope down arrangement where the PCMs are placed in the descending order of their melting temperatures. The second type of arrangement is the slope up arrangement where the PCMs are placed in the ascending order of their melting temperatures. Overall, the cascaded layout excels in performance when compared to the uniform layout in terms of PCM melting and solidification time and in terms of energy stored and extracted. Keeping these factors in mind, we recommend using a cascaded layout in a Thermal Energy Storage System (TESS) as opposed to a uniform layout.
Thermal Resistance of Polystyrene-Seeded Concrete for Better Insulative Value
Authors: Kobus Chris J. , Huyssen Michael , Piper Ryan , Schall J. David , Wang Xia , Guessous Laila
Published: January 2019

This paper details the experimentally-measured thermal conductivity, k, of concrete composite samples consisting of various mixtures of extruded polystyrene waste chips and concrete for the purpose of better insulative value and lighter weight. A “hot box” apparatus was designed based on the parameters of ASTM C1363, and was constructed primarily out of 4” rigid polystyrene insulation and designed to force the majority of the heat generated in the enclosure through the test samples. The design allowed for the indirect measurement of thermal conductivity, k, by directly measuring the internal and external surface temperatures of the samples and heat input required to maintain a steady state internal temperature. Several samples with well documented k values were first tested to calibrate the hot box apparatus. Prototype samples were made in sheets and also in cylindrical format to test for thermal conductivity and also compression testing, respectively. Results showed that although the insulative values of the concrete composite increased with additional polystyrene aggregate, as would be expected, at some point there is a rapid fall-off in compressive strength.
Water/Steam Injection for NOx Reduction in Process Burners
Authors: Londerville Steve , Anderson Kevin , Baukal Charles , Bussman Wes
Published: January 2019

Liquid water or steam injection is a technique that has been used for years to reduce NOx primarily by reducing the flame temperature which reduces thermal NOx. There is also evidence to suggest it reduces NOx by modifying the flame chemistry. While it is well proven for reducing NOx, there are some potential disadvantages including reduced thermal efficiency, flame instability, and increased emissions of other pollutants such as CO and unburned hydrocarbons. Water/steam injection has been used in a wide range of applications, particularly in boilers and gas turbines. Much less information is available on using this technique in process heaters which have some key differences compared to most combustors which include a highly varying fuel composition and natural draft to provide the combustion air. This paper will consider how water or steam may be injected into process burners including some predictive methods for determining NOx.
Design of a Robust Yaw Rate Controller Using Sliding Mode Control and Extended State Observer for Navigation of an Autonomous Ground Vehicle
Authors: Borate Suraj Shamrao , Sahoo Shubhashisa , Baby Devika K. , Subramanian Shankar C. , Mangrulkar Kiran K.
Published: January 2019

This paper deals with tracking of desired yaw rate generated by the path planner of an Autonomous Ground Vehicle (AGV) in the presence of unmodeled dynamics, changes in operating conditions and parametric uncertainties. A mathematical model considering the dynamics of the test vehicle and the steering actuator was used for controller design. The estimate of the unknown part of dynamics, called the total disturbance, obtained from the Extended State Observer (ESO) was used by Sliding Mode Controller (SMC) to compensate the actual total disturbance. It was observed that the lower bound on the SMC switching gain depends on the ratio of total disturbance estimation error and assumed known part of the system dynamics. This allows the choice of a low value of SMC switching gain, which in turn resulted in reduced chattering amplitude. Further attenuation in chattering was achieved using a saturation function.

After simulating the designed controller in MATLAB-SIMULINK environment, the controller was validated in IPG: CarMaker® simulation platform over a large operating range by changing the mass distribution of the vehicle, speed of the vehicle, cornering stiffness of the tire and terrain friction coefficient. A look-up table was formulated for the maximum achievable yaw rate at different speeds, i.e., from 5 to 20 m/s, given the maximum steering angle input considering rollover and slip threshold while the terrain friction coefficient was also varied from 0.2 to 0.8. It was observed that the designed controller was robust to changes in operating conditions, parametric uncertainties and unmodeled dynamics.
Simulation of Mouse Brain Tissue Under Controlled Cortical Impact
Authors: Zhao Haifeng , Lai Changxin , Wang Ke , Qiu Suhao , Wang Tianyao , Jiang Wenheng , Liu Jun , Li Xiangdong , Zeng Jianfeng , Feng Yuan
Published: January 2019

Traumatic brain injury is one of the leading causes of injury and death in both developed and developing countries. Animal models are important preclinical tools for injury level studies. In this study, a finite element (FE) model of mouse brain was constructed to investigate the biomechanical responses of brain tissue during a controlled cortical impact (CCI). Impact of the brain tissue was simulated with varying impact speeds and angles. Computational results indicated that the viscoelastic properties of the brain tissue and the impact angle could greatly influence the injury responses. Comparison with the experimental observation showed that energy based stress parameters such as the von Mises stress has the potential to be descriptive of the injury levels.
Comparing Fish-Inspired Ram Filters for Collection of Harmful Algae
Authors: Marshall Lauren , Schroeder Adam , Trease Brian
Published: January 2019

In this work, several different bioinspired filter geometries are proposed, fabricated, and tested in a flow tank. A novel approach is explored that mimics how filter-feeding fish efficiently remove small food particles from water. These filters generally take the form of a cone with water entering the large end of the cone and exiting through mesh-covered slots in the side of the cone, which emulates the rib structure of these filter-feeding fish. The flow in and around the filters is characterized and their ability to collect algae-scale, neutrally-buoyant particles is evaluated.

Filter performance is evaluated by using image processing to count the number of particles collected and studying how the particles are deposited on the filter. Results are presented in the form of particle collection efficiencies, which is a ratio of particles collected to the particles that would nominally enter the filter inlet, and images of the fluorescent particles deposited on the filter at different time intervals. The results show little sensitivity to the filters’ inlet geometries, which was the major difference between filters tested. Comparative results are also presented from a 2D CFD model of the filters generated in COMSOL. The different geometries may differentiate themselves more at larger Reynolds numbers, and it is believed that a fluid exit ratio, or ratio of inlet area to exit area, is the most critical filter parameter.

Field testing has demonstrated collection of real algae (i) with this bioinspired filter, and (ii) from a robot platform, but using a more conventional plankton net. The larger vision is to develop these filters and mount them on a swarm of autonomous surface vehicles, i.e. a robot boat swarm, which is being developed in parallel.
Forward masking enhances the auditory brainstem response in the free-tailed bat, Tadarida brasiliensis, during a critical time window for sonar reception
Authors: Smotherman Michael , Bakshi Kushal
Published: January 2019

Forward masking is a widespread auditory phenomenon in which the response to one sound transiently reduces the response to a succeeding sound. This study used auditory brainstem responses to measure temporal masking effects in the free-tailed bat, Tadarida brasiliensis. A digital subtraction protocol was used to isolate responses to the second of a pair of pulses varying in interval, revealing a suppression phase lasting <4 ms followed by an enhancement phase lasting 4–15 ms during which the ABR waveform was amplified up to 100%. The results suggest echolocating bats possess adaptations for enhancing sonar receiver gain shortly after pulse emission.
Human Intestinal Enteroids as a Model System of
Shigella
Pathogenesis
Authors: Koestler Benjamin J. , Ward Cara M. , Fisher C. R. , Rajan Anubama , Maresso Anthony W. , Payne Shelley M.
Published: January 2019

The enteric bacterium and intracellular human pathogen
Shigella
causes hundreds of millions of cases of the diarrheal disease shigellosis per year worldwide.
Shigella
is acquired by ingestion of contaminated food or water; upon reaching the colon, the bacteria invade colonic epithelial cells, replicate intracellularly, spread to adjacent cells, and provoke an intense inflammatory response.
Diversity and Population Overlap between Avian and Human Escherichia coli Belonging to Sequence Type 95
Authors: Jørgensen Steffen L. , Stegger Marc , Kudirkiene Eglé , Lilje Berit , Poulsen Louise L. , Ronco Troels , Pires Dos Santos Teresa , Kiil Kristoffer , Bisgaard Magne , Pedersen Karl , Nolan Lisa K. , Price Lance B. , Olsen Rikke H. , Andersen Paal S. , Christensen Henrik
Published: January 2019

APEC causes a range of infections in poultry, collectively called colibacillosis, and is the leading cause of mortality and is associated with major economic significance in the poultry industry. A growing number of studies have suggested APEC as an external reservoir of human ExPEC, including UPEC, which is a reservoir. ExPEC belonging to ST95 is considered one of the most important pathogens in both poultry and humans. This study is the first in-depth whole-genome-based comparison of ST95
E. coli
which investigates both the core genomes as well as the accessory genomes of avian and human ExPEC. We demonstrated that multiple lineages of ExPEC belonging to ST95 exist, of which the majority may cause infection in humans, while only part of the ST95 cluster seem to be avian pathogenic. These findings further support the idea that urinary tract infections may be a zoonotic infection.
Subacromial decompression surgery for adults with shoulder pain: a systematic review with meta-analysis
Authors: Lähdeoja Tuomas , Karjalainen Teemu , Jokihaara Jarkko , Salamh Paul , Kavaja Lauri , Agarwal Arnav , Winters Marinus , Buchbinder Rachelle , Guyatt Gordon , Vandvik Per Olav , Ardern Clare L
Published: January 2019

Objective

To determine the benefits and harms of subacromial decompression surgery in adult patients with subacromial pain syndrome lasting for more than 3 months.

Design

Systematic review with meta-analysis.

Main outcome measures

Pain, physical function and health-related quality of life.

Data sources

Systematic searches for benefits and harms were conducted to 23 July 2018 in MEDLINE, Embase, PubMed, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, Cumulative Index to Nursing and Allied Health Literature, Physiotherapy Evidence Database, ClinicalTrials.gov, WHO International Clinical Trials Registry Platform, Database of Abstracts of Reviews of Effects, and Health Technology Assessment.

Eligibility criteria for selecting studies

Randomised controlled trials comparing subacromial decompression surgery for subacromial pain syndrome with any other treatment(s). For harms, we included prospective cohort studies.

Review methods

Two reviewers independently determined eligibility, extracted the data and assessed the risk of bias of eligible studies. Thirty patients seeking primary or outpatient care for subacromial pain syndrome and a parallel guideline committee (
BMJ
Rapid Recommendations) provided input regarding systematic review design and interpretation.

Results

There was high certainty evidence of no additional benefit of subacromial decompression surgery over placebo surgery in reducing pain at 1 year following surgery (mean difference [MD] −0.26, 95% CI −0.84 to 0.33, minimally important difference [MID] 1.5) or improving physical function at 1–2 years (MD 2.8, 95% CI −1.4 to 6.9, MID 8.3). There was moderate certainty evidence for no additional benefit of subacromial decompression surgery on health-related quality of life at 1 year (MD −0.03 points, 95% CI −0.11 to 0.06, MID 0.07). There was moderate certainty evidence for six serious harms per 1000 (95% CI 5 to 7) patients undergoing subacromial decompression.

Conclusion

Subacromial decompression surgery provided no important benefit compared with placebo surgery or exercise therapy, and probably carries a small risk of serious harms.

Systematic reviewregistration number

CRD42018086862.
Optimisation of Perioperative Cardiovascular Management to Improve Surgical Outcome II (OPTIMISE II) trial: study protocol for a multicentre international trial of cardiac output-guided fluid therapy with low-dose inotrope infusion compared with usual care in patients undergoing major elective gastrointestinal surgery
Authors: Edwards Mark R , Forbes Gordon , MacDonald Neil , Berdunov Vladislav , Mihaylova Borislava , Dias Priyanthi , Thomson Ann , Grocott Michael PW , Mythen Monty G , Gillies Mike A , Sander Michael , Phan Tuong D , Evered Lisbeth , Wijeysundera Duminda N , McCluskey Stuart A , Aldecoa Cesar , Ripollés-Melchor Javier , Hofer Christoph K , Abukhudair Hussein , Szczeklik Wojciech , Grigoras Ioana , Hajjar Ludhmila A , Kahan Brennan C , Pearse Rupert M
Published: January 2019

Introduction

Postoperative morbidity and mortality in older patients with comorbidities undergoing gastrointestinal surgery are a major burden on healthcare systems. Infections after surgery are common in such patients, prolonging hospitalisation and reducing postoperative short-term and long-term survival. Optimal management of perioperative intravenous fluids and inotropic drugs may reduce infection rates and improve outcomes from surgery. Previous small trials of cardiac-output-guided haemodynamic therapy algorithms suggested a modest reduction in postoperative morbidity. A large definitive trial is needed to confirm or refute this and inform widespread clinical practice.

Methods

The Optimisation of Perioperative Cardiovascular Management to Improve Surgical Outcome II (OPTIMISE II) trial is a multicentre, international, parallel group, open, randomised controlled trial. 2502 high-risk patients undergoing major elective gastrointestinal surgery will be randomly allocated in a 1:1 ratio using minimisation to minimally invasive cardiac output monitoring to guide protocolised administration of intravenous fluid combined with low-dose inotrope infusion, or usual care. The trial intervention will be carried out during and for 4 hours after surgery. The primary outcome is postoperative infection of Clavien-Dindo grade II or higher within 30 days of randomisation. Participants and those delivering the intervention will not be blinded to treatment allocation; however, outcome assessors will be blinded when feasible. Participant recruitment started in January 2017 and is scheduled to last 3 years, within 50 hospitals worldwide.

Ethics/dissemination

The OPTIMISE II trial has been approved by the UK National Research Ethics Service and has been approved by responsible ethics committees in all participating countries. The findings will be disseminated through publication in a widely accessible peer-reviewed scientific journal.

Trial registration number

ISRCTN39653756.
Randomised controlled trial of the impact of haemodiafiltration on uraemic neuropathy: FINESSE study protocol
Authors: Smyth Brendan , Krishnan Arun V , Gallagher Martin , Kiernan Matthew , Snelling Paul , Hawley Carmel , Fernando Mangalee , Hand Samantha , Grimley Kim , Burman Jenny , Heath Anne , Kang Amy , Perkovic Vlado , Jardine Meg J
Published: January 2019

Introduction

The majority of patients undergoing haemodialysis (HD) show evidence of uraemic neuropathy, a condition with no known disease-modifying treatments. The pathogenesis of uraemic neuropathy is poorly understood, but may be related to cumulative exposure to middle molecules or other solutes such as potassium. It is not known whether haemodiafiltration (HDF) reduces the progression of uraemic neuropathy.

Methods and analysis

Filtration In the Neuropathy of End-Stage kidney disease Symptom Evolution (FINESSE) is a multicentre, randomised, open-label, blinded endpoint assessment, controlled trial designed to assess the impact of HDF versus HD on uraemic neuropathy. Maintenance HD patients will be randomised in a 1:1 ratio to receive HDF or HD with high-flux membranes for 4 years. The primary endpoint is the difference in the mean change in Total Neuropathy Score (TNS)—a measure of peripheral neuropathy combining symptoms, signs and nerve conduction velocity—over the study period. Secondary outcomes include change at annual timepoints in the TNS and the Neuropathy Symptom Score; and in morbidity, mortality and safety events.

Ethics and dissemination

The FINESSE trial has been approved by the Ethics Review Committee of the Sydney South West Area Health Service (HREC/09/RPAH/268) and of Adventist HealthCare Limited (2012–027). When published in a peer-reviewed journal, it will be the largest and longest reported randomised trial aimed at reducing the incidence and severity of uraemic neuropathy. It will advance the understanding of the natural history of uraemic neuropathy and the influence of convective therapies on both neurophysiological and clinical outcomes. It will also allow refinement of current hypotheses surrounding the pathogenesis of uraemic neuropathy and, most importantly, may lead to improvements in the lives of the many patients affected by this debilitating condition.

Trial registration number

ACTRN12609000615280.
Efficacy and safety of different drug monotherapies for tension-type headache in adults: study protocol for a Bayesian network meta-analysis
Authors: Xie Runsheng , Tian Jinhui , Wang Yangyang , Cai Yefeng , Li Hui
Published: January 2019

Introduction

Tension-type headache (TTH) is the most prevalent neurological disease, with an estimated 1.5 billion cases worldwide. Pharmacotherapy should be considered by patients with TTH who have a limited response to non-pharmacological treatment. However, recommendations for the vast array of therapeutic drugs for TTH partially overlap, with conflicting recommendations for strength in different guidelines; these may confuse the decision-making process of clinicians. Hence, the aims of this study are to analyse the available direct and indirect evidence on different drug monotherapies for TTH in adults, and to generate a treatment ranking according to their efficacy and safety outcomes by using a Bayesian network meta-analysis (NMA).

Methods and analysis

We will systematically search the Cochrane Library, PubMed, Web of Science, Embase, China Biomedical Literature Database, International Clinical Trials Registry Platform and other resources for eligible studies. Randomised controlled trials on different drug monotherapies for TTH will be included. Two review authors (RX and YW) will independently search and select the studies, extract the data and assess the risk of bias. A Bayesian NMA will afterwards be conducted to pool the effect measures across all types of monotherapy drugs. The ranking probabilities of the efficacy and safety of different drug monotherapies will be estimated. Heterogeneity will be quantified using the Q statistic and the I² index. Inconsistency between direct and indirect evidence will be assessed by the node-splitting model. In addition, the overall quality of evidence will be assessed using the Grading of Recommendations Assessment, Development and Evaluation approach.

Ethics and dissemination

No ethical issues are foreseen. The results will be published in a peer-reviewed journal, which will be disseminated electronically and in print.

PROSPERO registration number

CRD42018090554.
Treatment outcomes for eating disorders in Sweden: data from the national quality registry
Authors: Södersten Per , Brodin Ulf , Sjöberg Jennie , Zandian Modjtaba , Bergh Cecilia
Published: January 2019

Objective

To report the outcomes of eating disorders treatment in Sweden in 2012–2016.

Design

The number of patients treated and the number of patients not fulfilling an eating disorders diagnosis (remission) at 1 year of follow-up at the clinics listed in the National Quality Registry for Eating Disorders Treatment were analysed. The published outcomes at three clinics, which used survival analysis to estimate outcomes, were compared with their outcomes in the registry. Outcomes at the three biggest clinics were compared.

Setting

All eating disorders clinics.

Participants

All patients treated at eating disorders clinics.

Intervention

Cognitive–behavioural therapy at most clinics and normalisation of eating behaviour at the three clinics with published outcomes.

Outcome measure

Proportion of patients in remission.

Results

About 2600 patients were treated annually, fewer than half were followed up and remission rates decreased from 21% in 2014 to 14% in 2016. Outcomes, which differed among clinics and within clinics over time, have been publicly overestimated by excluding patients lost to follow-up. The published estimated rate of remission at three clinics that treated 1200 patients in 1993–2011 was 27%, 28% and 40% at 1 year of follow-up. The average rate of remission over the three last years at the biggest of these clinics was 36% but decreased from 29% and 30% to 16 and 14% at the two other of the biggest clinics.

Conclusions

With more than half the patients lost to follow-up and no data on relapse in the National Quality Registry, it is difficult to estimate the effects of eating disorders treatment in Sweden. Analysis of time to clinically significant events, including an extended period of follow-up, has improved the quality of the estimates at three clinics. Overestimation of remission rates has misled healthcare policies. The effect of eating disorders treatment has also been overestimated internationally.
Utilizing a 3S (strategies, source and setting) approach to understand the patient’s preferences when addressing medication non-adherence in patients with diabetes: a focus group study in a primary outpatient clinic
Authors: Unni Elizabeth J , Van Wagoner Eve , Shiyanbola Olayinka O
Published: January 2019

Objective

Non-adherence with diabetes medicines is a challenge. Approximately 54% of patients are non-adherent with their diabetes medicines. The objective of this study was to understand patients’ preferences when addressing non-adherence based on the 3S approach—strategies (what approaches can be used in addressing non-adherence), settings (when and where should the intervention happen) and sources (who should provide the intervention).

Design

A focus group research design was used.

Setting

A primary outpatient clinic from an integrated healthcare system in the USA.

Participants

Patients who were non-adherent with diabetes medicines.

Data collection

The focus group guide was based on the Medication Adherence Reasons Scale, which has 19 reasons identified for non-adherence. For each item in the scale, patients were asked for strategies that can be used in addressing that issue, the setting in which the interventions should be provided and the source to provide the interventions.

Data analysis

Open coding and content analysis.

Results

Two focus groups, each group having seven patients, were conducted. The major strategies identified were patient education, self-responsibility of patients, family support, reminders and societal support. The key educational needs were dealing with side effects and learning to use insulin properly, and a need for different learning styles when offering education. For the source, the major ones were physicians and pharmacists, having a continuous dialogue about the disease and medicines, and individuality in managing the disease. Respondents also recommended using a peer support group. For the setting, the patients preferred continuity of patient education throughout the disease.

Conclusion

The 3S approach was able to elicit several recommendations from patients to improve their adherence with diabetes medicines. Educational strategies were identified as the foremost approach coming from physicians and pharmacists throughout their disease journey, in addition to peer support.
Comorbidity and healthcare use for individuals with CVD in the Ireland: a cross-sectional, population-based study
Authors: Morrissey Karyn
Published: January 2019

Objective

This study explores the factors associated with health service use for individuals with cardiovascular disease (CVD) and comorbidity in the Ireland.

Design

Population-based cross-sectional survey.

Setting

Nationally representative health and health service use survey from the 2010 Quarterly National Household Survey was analysed.

Primary outcome measures

Four outcome variables were examined: no CVD, CVD only, CVD with CVD-related comorbidities and CVD with non-CVD-related comorbidity.

Results

Of the 791 individuals reporting doctor-diagnosed CVD, 77% had a second morbidity. Using type of healthcare coverage as a proxy for socioeconomic status, both CVD-related and non CVD-related comorbidity increases the use of health service usage substantially for individuals with CVD, particularly general practitioner services (8.47, CI 4.49 to 15.96 and 5.20, CI 2.10 to 12.84) and inpatient public hospital care (3.64, CI 2.93 to 4.51 and 3.00, CI 2.11 to 4.26).

Conclusion

This study indicated that even when demographic and socioeconomic factors are controlled for, comorbidity significantly increases the risk of accessing health services for individuals with CVD.
Fertility rates and the postponement of first births: a descriptive study with Finnish population data
Authors: Roustaei Zahra , Räisänen Sari , Gissler Mika , Heinonen Seppo
Published: January 2019

Objectives

We described the trend of fertility rates, age-specific fertility rates and associated factors in Finland over a 30-year period.

Design

A descriptive population-based register study.

Setting

Fertility data, including age at first birth, childlessness and educational levels were gathered from the Finnish Medical Birth Register and Statistics Finland.

Participants

All 1 792 792 live births from 1987 to 2016 in Finland.

Main outcome measures

Completed fertility rate, total fertility rate and age-specific fertility rate.

Results

The total fertility rate of Finnish women fluctuated substantially from 1987 to 2016. Since 2010, the total fertility rate has gradually declined and reached the lowest during the study period in 2016: 1.57 children per woman. The mean maternal age at first birth rose by 2.5 years from 26.5 years in 1987 to 29 years in 2016. The proportion of childless women at the age of 50 years increased from 13.6% in 1989 to 19.6% in 2016. By considering the impact of postponement and childlessness, the effect on total fertility rates was between −0.01 and −0.12 points. Since 1987, the distribution of birth has declined for women under the age of 29 and increased for women aged 30 or more. However, start of childbearing after the age of 30 years was related to the completed fertility rate of less than two children per woman. The difference in completed fertility rate across educational groups was small.

Conclusions

Postponement of first births was followed by decline in completed fertility rate. Increasing rate of childlessness, besides the mean age at first birth, was an important determinant for declined fertility rates, but the relation between women’s educational levels and the completed fertility rate was relatively weak.
Creatine and pregnancy outcomes, a prospective cohort study in low-risk pregnant women: study protocol
Authors: De Guingand Deborah L , Ellery Stacey J , Davies-Tuck Miranda L , Dickinson Hayley
Published: January 2019

Introduction

The creatine kinase circuit is central to the regulation of high-energy phosphate metabolism and the maintenance of cellular energy turnover. This circuit is fuelled by creatine, an amino acid derivative that can be obtained from a diet containing animal products, and by synthesis in the body de novo. A recent retrospective study conducted in a cohort of 287 pregnant women determined that maternal excreted levels of creatine may be associated with fetal growth. This prospective study aims to overcome some of the limitations associated with the previous study and thoroughly characterise creatine homeostasis throughout gestation in a low-risk pregnant population.

Methods and analysis

This study is recruiting women with a singleton low-risk pregnancy who are attending Monash Health, in Melbourne, Australia. Maternal blood and urine samples, along with dietary surveys, are collected at five time points during pregnancy and then at delivery. Cord blood and placenta (including membranes and cord) are collected at birth. A biobank of tissue samples for future research is being established. Primary outcome measures will include creatine, creatine kinase and associated metabolites in antenatal bloods and urine, cord bloods and placenta, along with molecular analysis of the creatine transporter (SLC6A8) and synthesising enzymes L - arginine:glycine amidinotransferase (AGAT) and guanidinoacetate methyltransferase (GAMT) in placental tissues. Secondary outcome measures include dietary protein intake over pregnancy and any associations with maternal creatine, pregnancy events and birth outcomes.

Ethics and dissemination

Ethical approval was granted in August 2015 from Monash Health (Ref: 14140B) and Monash University (Ref: 7785). Study outcomes will be disseminated at international conferences and published in peer-reviewed scientific journals.

Trial registration number

ACTRN12618001558213; Pre-results.
Validation of the hospital frailty risk score in a tertiary care hospital in Switzerland: results of a prospective, observational study
Authors: Eckart Andreas , Hauser Stephanie Isabelle , Haubitz Sebastian , Struja Tristan , Kutz Alexander , Koch Daniel , Neeser Olivia , Meier Marc A , Mueller Beat , Schuetz Philipp
Published: January 2019

Objectives

Recently, the Hospital Frailty Risk Score based on a derivation and validation study in the UK has been proposed as a low-cost, systematic screening tool to identify older, frail patients who are at a greater risk of adverse outcomes and for whom a frailty-attuned approach might be useful. We aimed to validate this Score in an independent cohort in Switzerland.

Design

Secondary analysis of a prospective, observational study (TRIAGE study).

Setting

One 600-bed tertiary care hospital in Aarau, Switzerland.

Participants

Consecutive medical inpatients aged ≥75 years that presented to the emergency department or were electively admitted between October 2015 and April 2018.

Primary and secondary outcome measures

The primary endpoint was all-cause 30-day mortality. Secondary endpoints were length of hospital stay, hospital readmission, functional impairment and quality of life measures. We used multivariate regression analyses.

Results

Of 4957 included patients, 3150 (63.5%) were classified as low risk, 1663 (33.5%) intermediate risk, and 144 (2.9%) high risk for frailty. Compared with the low-risk group, patients in the moderate risk and high-risk groups had increased risk for 30-day mortality (OR (OR) 2.53, 95% CI 2.09 to 3.06, p<0.001 and OR 4.40, 95% CI 2.94 to 6.57, p<0.001) with overall moderate discrimination (area under the ROC curve 0.66). The results remained robust after adjustment for important confounders. Similarly, we found longer length of hospital stay, more severe functional impairment and a lower quality of life in higher risk group patients.

Conclusion

Our data confirm the prognostic value of the Hospital Frailty Risk Score to identify older, frail people at risk for mortality and adverse outcomes in an independent patient population.

Trial registration number

NCT01768494; Post-results.
Complete relief of CRPS-associated pain during magnesium infusion in a patient with postpartum preeclampsia
Authors: Niconchuk Jonathan A , Richardson Michael G
Published: January 2019

A pregnant patient with chronic regional pain syndrome (CRPS) and indwelling spinal cord stimulator presented with twin gestation for induction of preterm labor due to preeclampsia. Intravenous magnesium was initiated and a lumbar epidural catheter was placed uneventfully for labor analgesia. The patient reported complete relief of her CRPS-associated pain during and for 24 hours after delivery, while receiving intravenous magnesium, with her pain symptoms returning shortly after discontinuing magnesium. To our knowledge, there are no case reports that describe CRPS-associated pain relief while on peripartum magnesium therapy.
Numerical analysis of pipeline response to slow landslides: case study
Authors: Katebi Mohammad , Maghoul Pooneh , Blatz James
Published: January 2019

A numerical analysis is carried out to study the behaviour of pipelines subjected to slow landslides at three at-risk landslide zones of Manitoba Pipeline Network. The pipeline’s longitudinal axis is parallel to the slow landslides at all three research sites. The ground displacements monitored for 5 years are imposed on the pipe using a special purpose pipe–soil interaction element (PSI element) using ABAQUS/Standard. The stiffness of PSI elements is defined based on soil–pipe interface properties according to a 2017 technical report from Pipeline Research Council International Inc. The results of the numerical analysis are compared with the instrumentation data to draw recommendations for future monitoring programs in slow landslide zones.