bluuebunny/crossref_metadata_2025 huggingface dataset:
Update on hysteroscopic sterilisation
Authors: Murthy Poornima , Edwards Jade , Pathak Mamta
Published: July 2017

Key content

A review of hysteroscopic sterilisation for permanent birth control.

The history and development of hysteroscopic sterilisation.

The best possible management of any complications.

The evidence relating to complications associated with the Essure Essure® device.

Learning objectives

To learn about the incidence of the long‐term risk of hysteroscopic sterilisation.

To be able to counsel women who are seeking this procedure.

To gain an overview of the management of long‐term complications.

Ethical issues

Women need to be informed of the long‐term risks to be able to make an informed choice.

Detailed discussion and awareness is needed to allow selecting the right method of contraception, covering both the positive and negative aspect of the method.

Medico‐legal implications.
Crack Growth Rates of Vertical Split Rim Wheel Failures
Authors: Stone Daniel H. , Dedmon Steven L.
Published: July 2017

The fatigue crack growth rates of three vertical split rim (VSR) wheel fractures are calculated using the Paris-Erdogan fatigue crack growth equation. Initial crack length, final crack length were measured for three wheels that have experienced VSR failures. The results of the calculations indicate the lives after crack initiation are relatively short. The results of these calculations indicate the timely reduction of the number of VSR failures should emphasize the prevention of the initiation of the VSR cracks.
Corrosion Control of Modern Light Rail Transit (LRT) Systems
Authors: Berman Michael , Williams Quentin P.
Published: July 2017

Since the introduction of electrified transit systems in the United States there has been a number of advancements in the field of corrosion control related to light rail transit (LRT) systems. Modern day direct current (dc) powered LRT systems have been designed with a variety of corrosion control features built-in.

Most of the research into corrosion control and the mitigation of stray currents known as electrolysis in the early days of electrified transit systems first appeared extensively in papers prepared and presented by personnel of the National Bureau of Standards. This research has led to better protection against corrosion of transit systems and nearby structures throughout the years.

Due to the ever increasing number of transit systems being built or upgraded, it’s essential to incorporate the installation, testing and monitoring of corrosion control measures in these transit systems. By integrating these corrosion control features into the design of LRT systems and subsystems, it will help to prevent premature corrosion failures on LRT fixed facilities and other structures. This paper identifies the main causes of corrosion and how corrosion control can be implemented into the design of LRT systems to prevent damage to the transit system and other structures.
Development of an Intelligent Module Used in Railway Level Crossings to Solve the Safety and Punctuality Issues in Urban Area
Authors: Lin Tu-Huan , Shih Yu-Lin , Jong Jyh-Cherng , Suen Chian-Shan
Published: July 2017

In urban area, frequent train services during peak hours often keep interrupting roadway traffic approaching level crossings (LXs). In Taiwan, more than 24 trains per hour pass the LXs in peak hours, and it leads to more than 40% time blocked by the barriers. To mitigate the potential risk of accidents between trains and roadway vehicles, almost 20% LXs had been installed with obstacle detection devices. It, however, leads to the following issues: (1) when the level crossings open and then close within a short period of time, the vehicles would likely be trapped in the dangerous area; (2) if the closing time at level crossings is not adjusted effectively, it would seriously impact the traffic flow and increase the possibility of trespassing; (3) the false alarm triggered by the obstacle detection devices has serious impact on train punctuality.

To mitigate the influence on roadside traffic and improve the safety, this study developed an intelligent module which consists of the following functions: (1) transmitting real-time videos of level crossings to the approaching trains, (2) constant alarm time for trains with different approaching speeds, and (3) extending alarm time for trains from the opposite directions within short time periods. A level crossing located on curved line in urban area was selected to test the performance of these functions in an actual scenario. Alternative solutions were also adopted in the tests to compare the performance for reference. The results show that the module can be viable in practice, but needs further works to ensure the safety, such as developing a fail-safe mechanism and overcoming the software security issues.
Locomotive Studies Utilizing Multibody and Train Dynamics
Authors: Spiryagin Maksym , Wu Qing , Sun Yan Quan , Cole Colin , Persson Ingemar
Published: July 2017

Locomotive traction studies have been extensively performed in multi-body software packages. Generally, these research activities have been focused on purely mechanical system design issues and, as a result, there is a limited amount of information available on modeling locomotives under the influence of traction/braking capabilities and train dynamics. Evidence of using results from longitudinal train dynamics simulations as input to locomotive dynamics simulations has also been limited and information on this is rarely presented in the public domain. This means that locomotive traction/braking studies are commonly focused on the dynamics of an individual locomotive and are limited in terms of implementation of intrain forces. Recent progress shows some activities involving the application of approximations of lateral coupler forces to replicate a locomotive’s dynamics on the track. However, such an approach has its own limitations and does not fully depict the real behavior of locomotives. At this stage, the optimal technique capable of covering all locomotive behavior issues when traveling in a train configuration is to use a co-simulation approach between a multibody software package and a train dynamics code. This paper describes a methodology for the development of such a technique and presents numerical experiments for locomotive dynamics studies. The results obtained from co-simulation runs for three heavy haul locomotives in a head-end consist, taking into account in-train forces and speeds, are discussed along with limitations found during the development process.
Prioritization of Rail Defect Inspection: A Risk-Based Optimization Approach
Authors: Zhou Kang
Published: July 2017

Broken rail is the most common type of mainline derailment cause on freight railroads in the United States. Detection and removal of rail defects is important for reducing the risk due to broken-rail-caused derailments. The current practice is to periodically inspect rails using non-destructive technologies, particularly ultrasonic inspection. Determining and prioritizing the frequency of rail defect inspection is an important decision in broken rail risk management. A generalized, risk-based mixed integer nonlinear programming (MINLP) model is developed which can optimize segment-specific rail defect inspection frequency to minimize route broken rail risk, especially under limited inspection resources. A numerical example to optimize the inspection frequency is used to illustrate the application of the model. The result analysis states that the optimization approach can lead to a risk reduction of broken rail compared to an empirical heuristic that all segments on the same route are tested at an equal frequency. A computer-aided decision making tool called “Rail Risk Optimizer” can be developed and implemented based on this risk-based optimization algorithm that automatically recommend an optimal segment-specific inspection scheduling. The tool will consider the risk factors such as rail age and annual traffic density to determine the segment-specific risk level. The research methodology and the practice-ready optimization tool can aid the railroad industry to mitigate broken rail risk in a cost-efficient manner.
A Joint Rail Conference Grand Challenge: Developing a Culture of Student/Rail Industry Problem Solving
Authors: Placencia Greg
Published: July 2017

We examine how establishing a competitive Joint Rail Conference Grand Challenges Initiatives can harness the potential of college and possibly high school students to develop solutions or new insight into technical and safety problems plaguing the rail industry, including safety.

The rail industry has tended to solve issues internally. However, solutions can often be found in other industries that are either similar or have faced similar concerns. For example, the immediate predecessor of Positive Train Control (PTC), the Advanced Railroad Electronics System (ARES), was conceived in the mid 1980’s by then Burlington Northern Railroad (BN) CEO Richard Bressler, who had read how flight safety and efficiency had been improved by air traffic control systems and avionics developed by Rockwell Collins for the Boeing 757 and 767 aircraft. The information age has further increased the potential for sparking innovation as ideas can spread literally overnight via the internet.

Some of the most talented and creative problems solvers are college and high school students, who have been greatly enabled by the “democratization” of information that has given them access to knowledge and skills as never before. Teens can learn nearly any skill watching reputable online videos or even “attend” classes offered by top universities around the world simply using a smart phone or tablet. This has prompted educators like Michigan Tech’s Dr. Pasi Lautala and other to develop extensive online rail educational resources to spark interest in the industry. However, simply passing on information has its limitation, which is why initiatives like the Grand Challenges, and Engineers without Borders have been instrumental in harnessing students to examine key global challenges in engineering, energy, and health care. Moreover, these initiatives have encouraged many students to pursue careers in those fields, even in low- and medium-income countries. For example, in 2012, a high school sophomore developed a new method to detect pancreatic cancer that is quick to administer and detects the disease much more quickly than previous methods, allowing much better chances for successful treatment. We will examine how establishing a competitive JRC Grand Challenges Initiatives can harness the potential of college and possibly high school students to develop solutions or establish new insight into technical and safety problems plaguing the rail industry, including safety. In addition, it will look at how developing a dialog among the rail industry, including the Class 1 railroads, students, and academia can encourage a more top notch, talented students to consider careers in the rail industry.
Planning the Ridesharing Route for the First-Mile Service Linking to Railway Passenger Transportation
Authors: Bian Zheyong , Liu Xiang
Published: July 2017

First-mile and last-mile travel is the bottleneck of using the public transportation service. This paper considers the passenger matching and vehicle routing problem in the first-mile ridesharing service connecting train schedules. Then a mixed integer model is proposed to formulate the problem. Since the problem is NP hard, we develop a simulated annealing (SA) algorithm with four neighborhood structures to solve this problem. Experiments are designed to test the proposed model and algorithm. The experimental results verify the effectiveness of the algorithm and demonstrate that the proposed algorithm can obtain satisfactory solutions within a reasonably short time.
Hysteresis Heating of Railroad Bearing Thermoplastic Elastomer Suspension Element
Authors: Rodriguez Oscar O. , Fuentes Arturo A. , Tarawneh Constantine , Jones Robert E.
Published: July 2017

Thermoplastic elastomers (TPE’s) are increasingly being used in rail service in load damping applications. They are superior to traditional elastomers primarily in their ease of fabrication. Like traditional elastomers they offer benefits including reduction in noise emissions and improved wear resistance in metal components that are in contact with such parts in the railcar suspension system. However, viscoelastic materials, such as the railroad bearing thermoplastic elastomer suspension element (or elastomeric pad), are known to develop self-heating (hysteresis) under cyclic loading, which can lead to undesirable consequences. Quantifying the hysteresis heating of the pad during operation is therefore essential to predict its dynamic response and structural integrity, as well as, to predict and understand the heat transfer paths from bearings into the truck assembly and other contacting components. This study investigates the internal heat generation in the suspension pad and its impact on the complete bearing assembly dynamics and thermal profile. Specifically, this paper presents an experimentally validated finite element thermal model of the elastomeric pad and its internal heat generation. The steady-state and transient-state temperature profiles produced by hysteresis heating of the elastomer pad are developed through a series of experiments and finite element analysis. The hysteresis heating is induced by the internal heat generation, which is a function of the loss modulus, strain, and frequency. Based on previous experimental studies, estimations of internally generated heat were obtained. The calculations show that the internal heat generation is impacted by temperature and frequency. At higher frequencies, the internally generated heat is significantly greater compared to lower frequencies, and at higher temperatures, the internally generated heat is significantly less compared to lower temperatures. However, during service operation, exposure of the suspension pad to higher loading frequencies above 10 Hz is less likely to occur. Therefore, internal heat generation values that have a significant impact on the suspension pad steady-state temperature are less likely to be reached. The commercial software package ALGOR 20.3TM is used to conduct the thermal finite element analysis. Different internal heating scenarios are simulated with the purpose of obtaining the bearing suspension element temperature distribution during normal and abnormal conditions. The results presented in this paper can be used in the future to acquire temperature distribution maps of complete bearing assemblies in service conditions and enable a refined model for the evolution of bearing temperature during operation.
Radiative Heat Transfer Analysis of Railroad Bearings for Wayside Hot-Box Detector Optimization
Authors: Mealer Arthur , Tarawneh Constantine , Crown Stephen
Published: July 2017

The railroad industry utilizes wayside detection systems to monitor the temperature of freight railcar bearings in service. The wayside hot-box detector (HBD) is a device that sits on the side of the tracks and uses a non-contact infrared sensor to determine the temperature of the train bearings as they roll over the detector. Various factors can affect the temperature measurements of these wayside detection systems. The class of the railroad bearing and its position on the axle relative to the position of the wayside detector can affect the temperature measurement. That is, the location on the bearing cup where the wayside infrared sensor reads the temperature varies depending on the bearing class (e.g., class K, F, G, E). Furthermore, environmental factors can also affect these temperature readings. The abovementioned factors can lead to measured temperatures that are significantly different than the actual operating temperatures of the bearings. In some cases, temperature readings collected by wayside detection systems did not indicate potential problems with some bearings, which led to costly derailments. Attempts by certain railroads to optimize the use of the temperature data acquired by these wayside detection systems has led to removal of bearings that were not problematic (about 40% of bearings removed were non-verified), resulting in costly delays and inefficiencies. To this end, the study presented here aims to investigate the efficacy of the wayside detection systems in measuring the railroad bearing operating temperature in order to optimize the use of these detection systems. A specialized single bearing dynamic test rig with a configuration that closely simulates the operating conditions of railroad bearings in service was designed and built by the University Transportation Center for Railway Safety (UTCRS) research team at the University of Texas Rio Grande Valley (UTRGV) for the purpose of this study. The test rig is equipped with a system that closely mimics the wayside detection system functionality and compares the infrared sensor temperature reading to contact thermocouple and bayonet temperature sensors fixed to the outside surface of the bearing cup. This direct comparison of the temperature data will provide a better understanding of the correlation between these temperatures under various loading levels, operating speeds, and bearing conditions (i.e. healthy versus defective), which will allow for an optimization of the wayside detectors. The impact on railway safety will be realized through optimized usage of current wayside detection systems and fewer nonverified bearings removed from service, which translates into fewer costly train stoppages and delays.
Evaluation of Grade Crossing Hazard Ranking Models
Authors: Sperry Benjamin R. , Naik Bhaven , Warner Jeffery E.
Published: July 2017

Public agencies involved with highway-railroad grade crossing safety must allocate available funding to projects which are considered the most in need for improvements. Mathematical models provide a ranking of hazard risk at crossings and support the project selection process. This paper reports the results of a research study sponsored by the Ohio Rail Development Commission (ORDC) and the Ohio Department of Transportation (ODOT) examining hazard ranking models for grade crossing project selection. The goal of the research was to provide ORDC, ODOT, and other stakeholders with a better understanding of the grade crossing hazard ranking formulas and other methods used by States to evaluate grade crossing hazards and select locations for hazard elimination projects. A comprehensive literature review along with personal interviews of state DOT personnel from eight states yielded best practices for hazard ranking and project selection. The literature review found that more than three-quarters of states utilize some type of hazard ranking formula or other systematic method for project prioritization. The most commonly-used hazard ranking model in use is the U.S. DOT Accident Prediction Model; however, at least eleven states utilize state-specific hazard ranking models. Detailed evaluation of several different hazard ranking models determined that the existing hazard ranking model used in Ohio, the U.S. DOT Accident Prediction Model, should continue to be used. The research also recommends greater use of sight distance information at crossings and expanding the preliminary list of crossings to be considered in the annual program as enhancements to the existing project selection process used by the ORDC and ODOT.
Selection of Representative Crossings Database for the Evaluation of Driver Behavior Over Highway-Rail Grade Crossings
Authors: Muhire Modeste , Lautala Pasi , Nelson David , Dean Aaron
Published: July 2017

While the literature suggests that driver behavior is the main cause of most of highway-rail grade crossing crashes, it has proven to be a challenging area for research. The SHRP2 Naturalistic Driving Study (NDS) opened a window of opportunity to make a systematic analysis of the phenomenon because it includes an in-vehicle direct observation of the drivers. The first step in the analysis was the selection process of approximately 300 representative crossings for analysis from over 1,000 crossings included in the NDS. In order to allow the analysis of driver behavior in various environments, the selected set was comprised of different types of crossings. Key parameters that were considered are the types of crossings based on the installed traffic control devices, the configuration of nearby intersections, and the number of accidents that took place at the crossing in recent years. From a statistical standpoint, each group must have a size large enough to generalize the observed conclusions across other crossings with similar characteristics. In addition to NDS, resources such as the FRA accident database, the FRA crossings inventory, and Google-Maps were used in order to determine the crossings that fit the selection criteria. In future steps of the project evaluation of driver behavior over selected crossings is expected to help identify patterns that carry high risk for highway-rail crossing accidents.
Effect of Particle Size and Shape Characteristics on Ballast Shear Strength: A Numerical Study Using the Direct Shear Test
Authors: Mishra Debakanta , Mahmud S. M. Naziur
Published: July 2017

The ballast layer serves as a major structural component in typical ballasted railroad track systems. When subjected to an external load, ballast particles present a complex mechanical response which is strongly dependent on particle to particle interactions within this discrete medium. One common test used to study the shear strength characteristics of railroad ballast is the Direct Shear Test (DST). However, it is often not feasible in standard geotechnical engineering laboratories to conduct direct shear tests on ballast particles due to significantly large specimen and test setup requirements. Even for the limited number of laboratories equipped to accommodate the testing of such large specimens, conducting repeated tests for parametric analysis of different test and specimen parameters on shear strength properties is often not feasible. Numerical modeling efforts are therefore commonly used for such parametric analyses. An ongoing research study at Boise State University is using the Discrete Element Method (DEM) to evaluate the effects of varying particle size and shape characteristics (i.e., flakiness, elongation, roundness, angularity) on direct shear strength behavior of railroad ballast. A commercially available three-dimensional DEM package (PFC3D®) is being used for this purpose. In numerical modeling, railroad ballasts can be simulated using spheres (simple approach) and non-breakable clumps (complex approach). This paper utilizes both approaches to compare the ballast stress-strain response as obtained from DST. Laboratory test results available in published literature are being used to calibrate the developed numerical models. This paper presents findings from this numerical modeling effort, and draws inferences concerning the implications of these findings on the design and construction of railroad ballast layers.
High frequency ultrasound imaging and simulations of sea urchin oocytes
Authors: Strohm Eric M. , Wirtzfeld Lauren A. , Czarnota Gregory J. , Kolios Michael C.
Published: July 2017

High frequency ultrasound backscatter signals from sea urchin oocytes were measured using a 40 MHz transducer and compared to numerical simulations. The Faran scattering model was used to calculate the ultrasound scattered from single oocytes in suspension. The urchin oocytes are non-nucleated with uniform size and biomechanical properties; the backscatter from each cell is similar and easy to simulate, unlike typical nucleated mammalian cells. The time domain signal measured from single oocytes in suspension showed two distinct peaks, and the power spectrum was periodic with minima spaced approximately 10 MHz apart. Good agreement to the Faran scattering model was observed. Measurements from tightly packed oocyte cell pellets showed similar periodic features in the power spectra, which was a result of the uniform size and consistent biomechanical properties of the cells. Numerical simulations that calculated the ultrasound scattered from individual oocytes within a three dimensional volume showed good agreement to the measured signals and B-scan images. A cepstral analysis of the signal was used to calculate the size of the cells, which was 78.7 μm (measured) and 81.4 μm (simulated). This work supports the single scattering approximation, where ultrasound is discretely scattered from single cells within a bulk homogeneous sample, and that multiple scattering has a negligible effect. This technique can be applied towards understanding the complex scattering behaviour from heterogeneous tissues.
When an emerging disease becomes endemic
Authors: Medley Graham F. , Vassall Anna
Published: July 2017

Epidemics, such as HIV in the early 1980s and Ebola in 2014, inspire decisive government investment and action, and individual and societal concern, sometimes bordering on panic. By contrast, endemic diseases, such as HIV in 2017 and tuberculosis, struggle to maintain the same attention. For many, the paradox is that endemic disease, in its totality, continues to impose a far higher public health burden than epidemic disease. Overall, the swift political response to epidemics has resulted in success. It has proven possible to eradicate epidemic diseases, often without the availability of vaccines and other biomedical technologies. In recent times, only HIV has made the transition from epidemic to endemic, but diseases that have existed for centuries continue to cause most of the infectious disease burden.
Global analysis of protein folding using massively parallel design, synthesis, and testing
Authors: Rocklin Gabriel J. , Chidyausiku Tamuka M. , Goreshnik Inna , Ford Alex , Houliston Scott , Lemak Alexander , Carter Lauren , Ravichandran Rashmi , Mulligan Vikram K. , Chevalier Aaron , Arrowsmith Cheryl H. , Baker David
Published: July 2017

Exploring structure space to understand stability

Understanding the determinants of protein stability is challenging because native proteins have conformations that are optimized for function. Proteins designed without functional bias could give insight into how structure determines stability, but this requires a large sample size. Rocklin
et al.
report a high-throughput protein design and characterization method that allows them to measure thousands of miniproteins (see the Perspective by Woolfson
et al.
). Iterative rounds of design and characterization increased the design success rate from 6 to 47%, which provides insight into the balance of forces that determine protein stability.

Science
, this issue p.
168
; see also p.
133
Snap deconvolution: An informatics approach to high-throughput discovery of catalytic reactions
Authors: Troshin Konstantin , Hartwig John F.
Published: July 2017

A triple search for coupling reactions

Coupling reactions are, in principle, good candidates for high-throughput discovery: Simply mix a diverse set of reagents and then look for products that combine two or three of their masses. In practice, however, numerous different products might have masses that are too similar to distinguish quickly. Troshin and Hartwig circumvented this problem by screening three pools of reagents in parallel that shared the same reactive functionality but differed in mass by carefully chosen increments. Specific products could then be identified in a noisy distribution by their distinctive expected mass differences across the three pools.

Science
, this issue p.
175
The elegant law that governs us all
Scale
Geoffrey West
Penguin Press, 2017. 490 pp.
Authors: Barabási Albert-László
Published: July 2017

A physicist probes a phenomenon seen in cells, cities, and almost everything in between
Response to Comment on “Molecular and neural basis of contagious itch behavior in mice”
Authors: Barry Devin M. , Yu Yao-Qing , Hao Yan , Liu Xue-Ting , Chen Zhou-Feng
Published: July 2017

Liljencrantz
et al
. report the failure of observing contagious itch behavior using mice injected with histamine as the demonstrators. Analysis of their results shows that the histamine model is limited by inadequate frequency and duration of scratching bouts required for contagious itch test. To streamline the contagious itch test, the screen paradigm is highly recommended.
Plasmonic imaging is gaining momentum
Authors: Basov D. N. , Fogler M. M.
Published: July 2017

Terahertz nanospectroscopy reveals many-body interactions in graphene
Of sizzling steaks and DNA repair
Authors: Dingler Felix A. , Patel Ketan J.
Published: July 2017

A pathway protects cells from mutations caused by sugar-derived aldehydes
An
In Vitro
Chicken Gut Model Demonstrates Transfer of a Multidrug Resistance Plasmid from
Salmonella
to Commensal
Escherichia coli
Authors: Card Roderick M. , Cawthraw Shaun A. , Nunez-Garcia Javier , Ellis Richard J. , Kay Gemma , Pallen Mark J. , Woodward Martin J. , Anjum Muna F.
Published: July 2017

The chicken gastrointestinal tract is richly populated by commensal bacteria that fulfill various beneficial roles for the host, including helping to resist colonization by pathogens. It can also facilitate the conjugative transfer of multidrug resistance (MDR) plasmids between commensal and pathogenic bacteria which is a significant public and animal health concern as it may affect our ability to treat bacterial infections. We used an
in vitro
chemostat system to approximate the chicken cecal microbiota, simulate colonization by an MDR
Salmonella
pathogen, and examine the dynamics of transfer of its MDR plasmid harboring several genes, including the extended-spectrum beta-lactamase
bla
CTX-M1
. We also evaluated the impact of cefotaxime administration on plasmid transfer and microbial diversity. Bacterial community profiles obtained by culture-independent methods showed that
Salmonella
inoculation resulted in no significant changes to bacterial community alpha diversity and beta diversity, whereas administration of cefotaxime caused significant alterations to both measures of diversity, which largely recovered. MDR plasmid transfer from
Salmonella
to commensal
Escherichia coli
was demonstrated by PCR and whole-genome sequencing of isolates purified from agar plates containing cefotaxime. Transfer occurred to seven
E. coli
sequence types at high rates, even in the absence of cefotaxime, with resistant strains isolated within 3 days. Our chemostat system provides a good representation of bacterial interactions, including antibiotic resistance transfer
in vivo
. It can be used as an ethical and relatively inexpensive approach to model dissemination of antibiotic resistance within the gut of any animal or human and refine interventions that mitigate its spread before employing
in vivo
studies.

IMPORTANCE
The spread of antimicrobial resistance presents a grave threat to public health and animal health and is affecting our ability to respond to bacterial infections. Transfer of antimicrobial resistance via plasmid exchange is of particular concern as it enables unrelated bacteria to acquire resistance. The gastrointestinal tract is replete with bacteria and provides an environment for plasmid transfer between commensals and pathogens. Here we use the chicken gut microbiota as an exemplar to model the effects of bacterial infection, antibiotic administration, and plasmid transfer. We show that transfer of a multidrug-resistant plasmid from the zoonotic pathogen
Salmonella
to commensal
Escherichia coli
occurs at a high rate, even in the absence of antibiotic administration. Our work demonstrates that the
in vitro
gut model provides a powerful screening tool that can be used to assess and refine interventions that mitigate the spread of antibiotic resistance in the gut before undertaking animal studies.
Severe destructive nasopharyngeal granulomatosis with polyangiitis with superimposed skull basePseudomonas aeruginosaosteomyelitis
Authors: von Itzstein Mitchell S , Abeykoon Jithma P , Summerfield Daniel D , Whitaker Jennifer A
Published: July 2017

Skull base osteomyelitis in the setting of granulomatosis with polyangiitis (GPA) is rare and entails significant diagnostic challenges. We present a case of a 65-year-old Caucasian man with a history of rheumatoid arthritis, off immunosuppression for 18 months, who presented with 2 years of chronic headaches, severe fatigue, saddle nose deformity and 20-kilogram unintentional weight loss. Maxillofacial CT revealed an extensive destructive sinonasal and erosive skull base process. Laboratory evaluation showed equivocal elevation of antiproteinase 3 antibodies with negative antineutrophil cytoplasmic antibody panel. Biopsy of the skull base/clivus revealed necrotising granulomatous inflammation with focal vasculitis consistent with GPA, and multiple bone cultures were positive forPseudomonas aeruginosa. This patient was diagnosed concurrently with GPA andP. aeruginosaskull base osteomyelitis. He was started on a 6-week course of cefepime intravenously and oral prednisone, with the plan to initiate rituximab infusion 2 weeks after initiation of antibiotic therapy.
Cystometrography of meningitis-retention syndrome
Authors: Tanaka Yuji , Satomi Kazuo
Published: July 2017

Although the combination of acute urinary retention and aseptic meningitis has not been well recognised, this combination can be referred to as meningitis-retention syndrome (MRS). We report a case of MRS with urodynamic follow-up. A 29-year-old man developed fever and headache, and after 7 days, he developed sudden urinary retention. Neurological examination indicated stiff neck, hyper-reflexes of the lower extremities. Cerebrospinal fluid examination showed mononuclear leucocytosis, increased protein level. Myelin basic protein was absent. MRI of the brain and spinal cord were normal. Cystometrography revealed an atonic bladder. The diagnosis was MRS. After 11 days of hospital day, his symptoms reduced rapidly, and on the 12th day, cystometrography revealed normal pattern. In mild cases, the symptoms reduced and the urodynamic examination improved rapidly. Although MRS is a rare symptom, its urodynamic assessment is important.
Interpretation of CIs in clinical trials with non-significant results: systematic review and recommendations
Authors: Gewandter Jennifer S , McDermott Michael P , Kitt Rachel A , Chaudari Jenna , Koch James G , Evans Scott R , Gross Robert A , Markman John D , Turk Dennis C , Dworkin Robert H
Published: July 2017

Objectives

Interpretation of CIs in randomised clinical trials (RCTs) with treatment effects that are not statistically significant can distinguish between results that are ‘negative’ (the data are not consistent with a clinically meaningful treatment effect) or ‘inconclusive’ (the data remain consistent with the possibility of a clinically meaningful treatment effect). This interpretation is important to ensure that potentially beneficial treatments are not prematurely abandoned in future research or clinical practice based on invalid conclusions.

Design

Systematic review of RCT reports published in 2014 inAnnals of Internal Medicine,New England Journal of Medicine,JAMA,JAMA Internal MedicineandThe Lancet(n=247).

Results

85 of 99 articles with statistically non-significant results reported CIs for the treatment effect. Only 17 of those 99 articles interpreted the CI. Of the 22 articles in which CIs indicated an inconclusive result, only four acknowledged that the study could not rule out a clinically meaningful treatment effect.

Conclusions

Interpretation of CIs is important but occurs infrequently in study reports of trials with treatment effects that are not statistically significant. Increased author interpretation of CIs could improve application of RCT results. Reporting recommendations are provided.
Predictors of emergency department use by adolescents and adults with autism spectrum disorder: a prospective cohort study
Authors: Lunsky Yona , Weiss Jonathan A , Paquette-Smith Melissa , Durbin Anna , Tint Ami , Palucka Anna M , Bradley Elspeth
Published: July 2017

Objectives

To determine predictors of emergency department (ED) visits in a cohort of adolescents and adults with autism spectrum disorder (ASD).

Design

Prospective cohort study.

Setting

Community-based study from Ontario, Canada.

Participants

Parents reported on their adult sons and daughters with ASD living in the community (n=284).

Main outcome measures

ED visits for any reason, ED visits for medical reasons and ED visits for psychiatric reasons over 1 year.

Results

Among individuals with ASD, those with ED visits for any reason were reported to have greater family distress at baseline (p<0.01), a history of visiting the ED during the year prior (p<0.01) and experienced two or more negative life events at baseline (p<0.05) as compared with those who did not visit the ED. Unique predictors of medical versus psychiatric ED visits emerged. Low neighbourhood income (p<0.01) and living in a rural neighbourhood (p<0.05) were associated with medical but not psychiatric ED visits, whereas a history of aggression (p<0.05) as well as being from an immigrant family (p<0.05) predicted psychiatric but not medical emergencies.

Conclusions

A combination of individual and contextual variables may be important for targeting preventative community-based supports for individuals with ASD and their families. In particular, attention should be paid to how caregiver supports, integrative crisis planning and community-based services may assist in preventing or minimising ED use for this vulnerable population.
Predictors of repeat visits to hospital psychiatric emergency departments in Malaga (Spain) and in Lisbon (Portugal)
Authors: Moreno-Küstner Berta , Warnke Ingeborg , Nordt Carlos , Fernandez Gemma , Ramos José , Paulino-Matos Pedro , Rössler Wulf , Cardoso Graça
Published: July 2017

Objective

This study describes the profile of people with mental disorders attending emergency departments (EDs) in two countries and to identify specific mental disorders associated with repeat emergency visits.

Methods

Retrospective analyses of 1 year of EDs data from two hospitals with psychiatric departments, one in Amadora/Sintra (Lisbon, Portugal, 2008) and the other in Malaga (Spain, 2009), were carried out. To determine which mental disorders were associated with repeat visits in each setting, negative binomial models were calculated.

Results

There were 5141 visits for a mental disorder made by 3667 patients. Patients with affective disorder were the most frequent (32.2%). Among all mental health patients, 19.9% had at least one repeat visit during the year. For the two EDs setting combined, patients with personality disorders (incidence rate ratio (IRR)=3.79, 95% CI: 2.39 to 6.02) and psychotic disorders (IRR=1.46, 95% CI: 1.13 to 1.89) were more likely to have repeat visits compared with patients with affective disorders, whereas mental disorders due to psychoactive substance use (IRR=0.52, 95% CI: 0.37 to 0.73) was associated with lower likelihood of repeat visits. Nearly all significant differences were attributable to the Malaga sample, where patients with personality disorders were four times more likely to have repeat EDs visits compared with patients with affective disorders. However, at both sites, patients with mental disorders due to psychoactive substance use were less likely to have repeat visits.

Conclusions

Certain mental disorders may be predictive of more frequent ED visits. The different results for each country suggest that further studies might focus not only on the characteristics of patients, but also on local healthcare organisation.
Profile and outcomes of critically ill children in a lower middle-income country
Authors: Habib Muhammad Irfan , Khan Khalid Mehmood A
Published: July 2017

Objective

To determine the clinical profile and outcome of critically ill children presenting to a paediatric ED in a lower middle-income country.

Methods

We performed a retrospective analysis of children (<14 years) presenting to the ED of the National Institute of Child Health, Karachi, between January and December 2014 who were assigned to acuity 1 (requiring immediate life-saving interventions) according to the Emergency Severity Index. Data included demographic variables, presenting complaints, interventions and outcomes in the ED.

Results

There were 172 162 visits during the year. Of these, 13 551 (8%) were level 1. 64% of level 1 patients were transported to the ED without ambulance service. Neonates (0–28 days) constituted 48% of level 1 children; their most frequent presenting complaints were respiratory symptoms, followed by fever and reluctance to feed. Above the neonatal age group, the most common presenting complaints were gastrointestinal symptoms (with signs of hypoperfusion), followed by seizures, reluctance to feed and respiratory symptoms. 64% of children of >28 days presenting were malnourished. Interventions included cardiopulmonary resuscitation, application of bubble continuous positive airway pressure and endotracheal intubation. Overall mortality was 13%; 63% of all deaths were in the neonatal age group.

Conclusion

Children with the highest triage acuity represent 8% of all visits to a paediatric ED. In this group, neonates account for nearly half of all the children, and more than half of all the deaths among critically ill children came in ED. A large proportion of high-acuity children are malnourished.
Introduction of a new imaging guideline for suspected renal colic in the ED reduces CT urography utilisation
Authors: Blecher Gabriel , Meek Rob , Egerton-Warburton Diana , McCahy Philip
Published: July 2017

Background

Patients presenting to the ED with suspected renal colic are frequently imaged with CT urography (CTU), which rarely alters diagnosis or management. To reduce use of CTU in this population, we instigated a new imaging and management guideline in our ED.

Methods

This was a quasi-experimental prospective study, whereby a new guideline was commenced at the intervention site (Monash Medical Centre) and the existing guideline continued at the control site (Dandenong Hospital). The new guideline promotes focused ultrasound for diagnosing renal colic and restricts CT to those with poor response to analgesia or ‘red flags’. A consecutive series of patients with suspected renal colic were prospectively enrolled and outcomes compared between the sites. The primary outcome was CTU utilisation and secondary outcomes were radiation exposure, stone rate on CTU, admission, ED length of stay and rates of urological intervention and returns to ED at 4-week follow-up.

Results

Preintervention CTU rates were 76.7% at Monash and 72.1% at Dandenong. 324 patients were enrolled; 148 at Monash and 176 at Dandenong. Median age 47 years vs 49 years, males 76.4% vs 66.5% and medianSex, Timing, Origin, Nausea, Erythrocytes (STONE) score 10 vs 10 for Monash and Dandenong, respectively. CTU was performed in 54.1% vs 75.0% (p<0.001), median radiation exposure 2.8 vs 4.0 mSv (p<0.001) and urological intervention occurred in 16.4% vs 15.7% for Monash and Dandenong, respectively.

Conclusions

We found that use of CTU for renal colic was significantly reduced by introduction of a guideline promoting ultrasound and encouraging selective CTU. Although intervention rates were similar between the two sites, further prospective study is needed to ensure other patient-centred outcomes do not differ.
BET 1: Lidocaine with propofol to reduce pain on injection
Authors: Baombe Janos P , Howard Laura
Published: July 2017

A short review was carried out to see if mixing lidocaine with propofol is a safe and effective method in reducing the commonly reported pain at the injection site. Four relevant papers were found using the described search strategy. The author, date and country of publication, patient group studied, study type, relevant outcomes, results and study weaknesses of these papers are tabulated. Although a promising idea, a paucity of good quality evidence suggests further needed research.
Patient–physician collaboration in rheumatology: a necessity
Authors: Nikiphorou Elena , Alunno Alessia , Carmona Loreto , Kouloumas Marios , Bijlsma Johannes , Cutolo Maurizio
Published: July 2017

Over the past few decades, there has been significant and impressive progress in the understanding and management of rheumatic diseases. One of the key reasons for succeeding in making this progress has been the increasingly stronger partnership between physicians and patients, setting a milestone in patient care. In this viewpoint, we discuss the recent evolution of the physician–patient relationship over time in Europe, reflecting on the ‘journey’ from behind the clinic walls through to clinical and research collaborations at national and international level and the birth of healthcare professional and ‘rheumatic’ patient organisations. The role of expert patients and patient advocates in clinical and scientific committees now represents a core part of the decision-making process. In more recent years and following the recognition that the young patients, physicians and academics have a voice and needs of their own, including the need to be educated and instructed, has encouraged the establishment of youth organisations, enabling change and innovation to take place at a uniquely different level.
Steady-state analytical model for vapour-phase volatile organic compound (VOC) diffusion in layered landfill composite cover systems
Authors: Xie Haijian , Wang Qiao , Yan Huaxiang , Chen Yunmin
Published: July 2017

An analytical model for the diffusion of one-dimensional vapour-phase volatile organic compounds (VOCs) through a four-layer landfill composite cover system consisting of a protective layer, drainage layer, geomembrane (GMB), and compacted clay liner (CCL) is developed. Effects of degree of water saturation (Sr), adsorption, and degradation on vapour-phase VOC diffusion in a cover system are then analyzed. The vapour-phase benzene concentration profile increases with increase of Sr in the drainage and protective layers. When Sr1 = Sr2 = 0.5 (where Sr1 and Sr2 are degree of water saturation of the protective and drainage layers, respectively), surface flux for the case with the degree of water saturation of the CCL layer Sr4 = 0.3 is 1.3 and 1560 times larger than that with Sr4 = 0.7 and = 0.9, respectively. The effect of adsorption of the VOCs in the CCL on performance of the cover system is more important than that in the drainage and protective layers. Surface flux and concentration of benzene tends to be zero when CCL is amended with 0.5% biochar due to an increase of the retardation factor. The effect of degradation rate on benzene concentration increases with increase of degree of water saturation. The influence of half-life of VOCs in the soil layer, t1/2, on vapour-phase VOC concentration can be neglected when Sr ≤ 0.3.
Dynamic installation of a torpedo anchor in two-layered clays
Authors: Kim Y.H. , Hossain M.S. , Lee J.K.
Published: July 2017

The behaviour of a torpedo anchor during dynamic installation in two-layered nonhomogeneous clay sediments was investigated through large-deformation finite-element (LDFE) analyses. Parametric analyses were undertaken varying the top layer thickness and strength ratio between two layers. Results show that the location of the demarcation point between the acceleration and deceleration phases of the anchor in the soil relative to the layer interface is the key factor directing the anchor behaviour in layered soils including the final embedment depth. Broadly speaking, the anchor behaviour in soft-over-stiff clay deposits is somewhat similar to that in single layer clay with strength increasing with depth. In stiff-over-soft clay deposits, the anchor penetrates deeper where the anchor deceleration phase (or the demarcation point) falls within the soft layer. Where the demarcation point lies within the top stiff layer, the anchor penetration depth decreases with increasing strength ratio, and the anchor penetration is terminated between the two layers for strength ratios ≥15. For assessing the anchor embedment depth in two-layered fine-grained ocean sediments in the field, an extended total energy–based method, along with a design expression, is proposed.