bluuebunny/crossref_metadata_2025 huggingface dataset:
A Practical Drilling Riser and Wellhead Vortex Induced Vibration Fatigue Comparison Between Analysis and Field Measured Data
Authors: Ge Michael Long , Kannala Jomon , Cain David , Kebadze Elizbar B. , Sundararaman Shankar , Krapf Carlyn , Li Zhen
Published: October 2015

In order to design a drilling riser system that meets the operational requirements, it is industry practice to use analytical tools to predict the riser and wellhead fatigue damage. This paper focuses on the comparison between the analysis and field measurements for both the drilling riser and wellhead vortex induced vibration (VIV) fatigue damage, during a recent loop current event in the Gulf of Mexico. The field data, which includes the drilling riser configuration, riser tensioner setting, and loop current data, were considered in this comparison. As one of the key contributors to VIV fatigue, the loop current, was measured from a survey vessel in the field during the blowout preventer (BOP) latched and retrieval period. The analysis utilized the VIV program SHEAR7 V4.6 to calculate the fatigue damage for both the drilling riser and wellhead system. The field measured acceleration data from the installed monitoring system was converted to the fatigue damage by transfer function methods. Key findings and conclusions are summarized to improve future analysis predictions of drilling riser and wellhead fatigue damage.
Vertical Penetration of Offshore Pipelines: A Comparative Study Between Finite Element and Finite Volume Methods
Authors: Dutta Sujan , Hawlader Bipul , Phillips Ryan
Published: October 2015

Deepwater surface laid pipelines generally penetrate a fraction of their diameter into the seabed. The near surface penetration behaviour of steel catenary risers (SCRs) is equally important in offshore oil and gas developments. Theoretical, physical and numerical investigations have been performed to understand pipeline–soil interaction during vertical penetration. The large deformation finite element (LDFE) modeling is a recent and advanced tool among different numerical modeling techniques. The authors of this study simulated the penetration of pipeline using Abaqus CEL Finite Element (FE) software [1]. They also developed a numerical modeling technique based on finite volume approach using ANSYS CFX [2] and showed some of its advantages. However, in that study an ideal soil (i.e. no softening or strain rate effects on undrained shear strength) was used. Strain rate and softening have significant effects on penetration behaviour and therefore in this study a numerical technique has been developed to incorporate these effects in ANSYS CFX. Comparison of the results shows that ANSYS CFX can also model the penetration behaviour. Moreover, ANSYS CFX has some advantages including low computational time, modeling of suction and pipeline–soil–water interaction. A parametric study is also presented to provide more insights into the pipeline–soil–water interaction.
Effects of Post-Peak Softening Behavior of Dense Sand on Lateral and Upward Displacement of Buried Pipelines
Authors: Roy Kshama , Hawlader Bipul , Kenny Shawn , Moore Ian
Published: October 2015

Buried pipelines are extensively used in onshore and offshore for transportation of hydrocarbons. The response of pipeline due to lateral and upward relative displacements is one of the major concerns in pipeline design. Both physical modeling and numerical analyses have been performed in the past to understand pipeline-soil interaction mechanisms. The numerical analyses are generally performed using finite element (FE) modeling techniques. For the pipelines buried in sand, a large number of analyses available in the literature have been performed using the Mohr-Coulomb model assigning constant values of angle of internal friction (ϕ′) and dilation (ψ). However, dense sand shows post-peak softening behavior and the behavior of sand also depends on mode of shearing, such as triaxial (TX), direct shear (DS) or direct simple shear (DSS) conditions. In the present study, FE analysis of buried pipelines in dense sand is presented. The first set of analyses are performed using the built-in Mohr-Coulomb model in Abaqus FE software with constant angles of internal friction and dilation, as typically used in previous FE analysis of pipeline-soil interaction. The second set of analyses are performed using a modified Mohr-Coulomb model where pre-peak hardening, post-peak softening, density and confining pressure dependent friction and dilation angles are considered. The FE analyses are performed using the Arbitrary Lagrangian-Eulerian (ALE) approach available in Abaqus/Explicit FE software. The modified Mohr-Coulomb model is implemented in Abaqus FE software using a user defined subroutine. Shear band formation due to strain localization and failure patterns for both lateral and upward pipeline-soil interactions are discussed from the simulations with MC and MMC models. FE results show that the MMC model can simulate the load-displacement behavior and failure pattern better than the simulations with the MC model.
Numerical Simulation of Upheaval Buckling Using “Intelligent” Backfill Soil Springs
Authors: Yonatan Prigiarto Hokkal , Van den Abeele Filip , Ballard Jean-Christophe
Published: October 2015

Designing the cover height of buried pipelines to prevent them from buckling requires a method that can thoroughly and realistically model the phenomenon. This paper introduces a new technique to assess the risk of upheaval buckling (UHB) by using backfill soil springs (BFSS) to represent the uplift resistance provided by the backfill soil on top of a buried pipeline. This paper investigates the pre-buckling pipeline behavior related to UHB and highlights some of the key parameters governing the analysis. UHB assessment based on a case study was carried out and the results were then compared with those obtained from force-equilibrium methods generally used in the industry. The comparison shows that UHB assessment can be performed more rigorous using BFSS than using force-equilibrium methods. Therefore, using BFSS for UHB assessment improve the reliability in cover height design.
Lift Installation of a Subsea Oil Storage Tank: A 60,000mT Pendulum
Authors: Velema Jorick , Bokhorst Job
Published: October 2015

In August 2014 Heerema Marine Contractors (HMC) have successfully installed the Solan Subsea Oil Storage Tank (SOST), using its Semi-Submersible Crane Vessel (SSCV) Thialf. The SOST installation is regarded as unique due to its dimensions, complex hydrodynamics and the utilization of nearly the full crane capacity.

The Solan SOST is a Subsea Oil Storage Tank with a future storage capacity of 48,000 m3 of oil. The SOST has a dimension of 45m × 45m × 25m, a dry weight of 9,500mT and a total submerged mass of 60,000mT including ballast water. It was installed offshore west of the Shetland Islands at a depth of 135m. Prior to installation the SOST was wet-towed to the field. At location the SOST was installed by a dual crane lift sequence, lowering the SOST from 2m freeboard to the seabed. The lowering sequence is characterized by the usage of a compressible air pocket to reduce hookloads during the most critical stage of the installation, the lowering of the SOST through the splash zone.

Prior to the installation ballast and dynamic lift models were generated to understand both the hydrostatics and hydrodynamics of the SOST - SSCV Thialf system throughout the installation. Numerical simulations of the flooding operation were performed to predict all relevant parameters for various scenarios. The lift dynamics were analysed with frequency domain models. Most resonance modes between SSCV Thialf and SOST were found not to be excited due to the differences in natural periods of the hydrodynamic systems and the occurring wave periods.

During installation vital parameters such as ballast volume, compartment fill rates, differential pressure and hookloads were continuously monitored with dedicated measurement systems. The values were compared with the results from the engineering models. As some of the parameters were directly related to each other, the values could be back-calculated and cross-checked, thereby increasing the reliability of the measurements.

Both the understanding of the principle hydrostatics and hydrodynamics of the system as well as the close monitoring of all vital parameters have resulted in a safe and controlled installation of the Solan SOST by the SSCV Thialf; the installation of a 60,000mT dual crane pendulum. This paper describes the hydromechanic engineering work performed by HMC and the SOST offshore installation.
Temporal Changes in Pipeline-Seabed Condition, and Their Effect on Operating Behaviour
Authors: White D. J. , Leckie S. H. F. , Draper S. , Zakarian E.
Published: October 2015

It is increasingly recognized that the state of the seabed surrounding an on-bottom pipeline may change during the operating life of the pipeline. For seabed sediments that are soft and fine-grained, the strength may vary through episodes of pipeline movement due to consolidation effects. For seabed sediments that are mobile due to waves and currents, the burial state and the adjacent seabed topography may vary due to sediment transport and scour.

These changes in the strength and topography of the surrounding seabed alter the exposure of the pipeline to hydrodynamic loads and ambient cooling, as well as the level of geotechnical support and insulation provided by the seabed.

The design relevance of these changes in seabed condition is amplified by modern design approaches in which the pipeline itself can be tolerably mobile — for example in a dynamic onbottom stability approach or through engineered schemes of global buckling and axial walking.

This paper illustrates the interactions between the geotechnical and sediment transport processes and the resulting global pipeline behaviour. Two interactions are considered: the long-term axial walking behaviour on soft soil, and the long-term insulation and temperature profile on a mobile seabed.

The examples highlight the potential for over or underestimation of various inputs to a pipeline design when these temporal changes in pipe-seabed condition are overlooked. Emerging analysis methods for pipeline-seabed interaction that incorporate these temporal effects can lead to more reliable and cost-effective design.
Finite Element Modeling of Large Diameter Monopiles in Dense Sand for Offshore Wind Turbine Foundations
Authors: Ahmed Sheikh Sharif , Hawlader Bipul , Roy Kshama
Published: October 2015

With increasing demand of energy, attention to the alternative sources of sustainable energy is getting priority over the last decades. Offshore wind turbine is one of them. The most widely used foundation system for the wind turbine is the monopile, which is a large diameter single pile. In the present study, three-dimensional finite element (FE) analyses are performed to evaluate the capacity of large diameter monopiles in dense sand using the Arbitrary Lagrangian-Eulerian (ALE) approach available in Abaqus/Explicit FE software. The behavior of sand is modeled using the Mohr-Coulomb (MC) and a modified Mohr-Coulomb (MMC) model where the pre-peak hardening, post-peak softening and the effects of mean effective stress and relative density on stress-strain behavior of dense sand are considered. Comparison with physical model test results shows that the MMC model can simulate better the load-displacement response than that with the MC model. The mechanisms involved in soil deformation are also explained using FE results.
Numerical Study on the Effect of Tandem Spacing on Flow Induced Motions of Two Cylinders With Passive Turbulence Control
Authors: Ding Lin , Zhang Li , Wu Chunmei , Kim EunSoo , Bernitsas Michael M.
Published: October 2015

The effect of tandem spacing on the flow induced motions (FIM) of two circular cylinders with passive turbulence control is investigated using two-dimensional Unsteady Reynolds-Average Navier-Stokes equations with the Spalart-Allmaras turbulence model. Results are compared to experiments in the range of Reynolds number of 30,000<Re<100,000. The center-to-center spacing between the two cylinders is varied from 2 to 6 diameters. Simulation results predict well all ranges of FIM including VIV and galloping and match well with experimental measurements. For the upstream cylinder, the amplitude and frequency responses are not considerably influenced by the downstream cylinder when the spacing is greater than 2D. For the downstream cylinder, a rising amplitude trend in the VIV upper branch can be observed in all cases as is typical of flows in the TrSL3 regime. The galloping branch merges with the VIV upper branch for spacing greater than 3D. Vortex structures show significant variation in different flow regimes in accordance with experimental observations. High-resolution post-processing shows that the interaction between the wakes of cylinders result in various types of FIM.
A pencil beam approach to proton computed tomography
Authors: Rescigno Regina , Bopp Cécile , Rousseau Marc , Brasse David
Published: October 2015

Purpose:

A new approach to proton computed tomography (pCT) is presented. In this approach, protons are not tracked one‐by‐one but a beam of particles is considered instead. The elements of the pCT reconstruction problem (residual energy and path) are redefined on the basis of this new approach. An analytical image reconstruction algorithm applicable to this scenario is also proposed.

Methods:

The pencil beam (PB) and its propagation in matter were modeled by making use of the generalization of the Fermi–Eyges theory to account for multiple Coulomb scattering (MCS). This model was integrated into the pCT reconstruction problem, allowing the definition of the mean beam path concept similar to the most likely path (MLP) used in the single‐particle approach. A numerical validation of the model was performed. The algorithm of filtered backprojection along MLPs was adapted to the beam‐by‐beam approach. The acquisition of a perfect proton scan was simulated and the data were used to reconstruct images of the relative stopping power of the phantom with the single‐proton and beam‐by‐beam approaches. The resulting images were compared in a qualitative way.

Results:

The parameters of the modeled PB (mean and spread) were compared to Monte Carlo results in order to validate the model. For a water target, good agreement was found for the mean value of the distributions. As far as the spread is concerned, depth‐dependent discrepancies as large as 2%–3% were found. For a heterogeneous phantom, discrepancies in the distribution spread ranged from 6% to 8%. The image reconstructed with the beam‐by‐beam approach showed a high level of noise compared to the one reconstructed with the classical approach.

Conclusions:

The PB approach to proton imaging may allow technical challenges imposed by the current proton‐by‐proton method to be overcome. In this framework, an analytical algorithm is proposed. Further work will involve a detailed study of the performances and limitations of this approach in terms of image quality. The paper shows how to account for the MCS in the reconstruction step with this new approach when an analytical reconstruction algorithm is used.
Apparatus for investigating resonance with application to magnetic resonance imaging
Authors: Murphy Sytil , Jones Dyan L. , Gross Josh , Zollman Dean
Published: October 2015

Resonance is typically studied in the context of either a pendulum or a mass on a spring. We have developed an apparatus that enables beginning students to investigate resonant behavior of changing magnetic fields, in addition to the properties of the magnetic field due to a wire and the superposition of magnetic fields. In this resonant system, a compass oscillates at a frequency determined by the compass's physical properties and an external magnetic field. While the analysis is mathematically similar to that of the pendulum, this apparatus has an advantage that the magnetic field is easily controlled, while it is difficult to control the strength of gravity. This apparatus has been incorporated into a teaching module on magnetic resonance imaging.
A perspective on motion sensors and free-fall
Authors: Boucher Derrick E.
Published: October 2015

When an ultrasonic motion sensor is not aligned correctly with an object's motion, the geometry of the transmitted and reflected sonar signals leads to an underestimate of velocity. This is not a large effect under most teaching laboratory conditions, but compounding such an error in the production of acceleration data can produce surprisingly large overestimates. Presented here is an analysis of the general problem for free-fall experiments, followed by experimental data that show the relative importance of these errors.
Measuring the impact of an instructional laboratory on the learning of introductory physics
Authors: Wieman Carl , Holmes N. G.
Published: October 2015

We have analyzed the impact of taking an associated lab course on the final exam scores in two large introductory physics courses. Performance between students who did and did not take the lab course was compared using final exam questions from the associated courses that related to concepts from the lab courses. The population of students who took the lab in each case was somewhat different from those who did not enroll in the lab course in terms of background and major. Those differences were taken into account by normalizing their performance on the lab-related questions with scores on the exam questions that did not involve material covered in the lab. The average benefit on lab-related questions for students who took the lab, in both courses, was within 0.6% of the score of students who did not, with an uncertainty of less than 2%. This result raises questions as to the effectiveness of labs at supporting mastery of physics content.
Note on the minimum critical mass for a tamped fission bomb core
Authors: Reed B. Cameron
Published: October 2015

An approximate but sensibly accurate formula is developed for estimating the minimum possible critical radius for a sphere of fissile material surrounded by a thick tamper of material of neutron transport mean free path λtamp. The minimum critical radius is approximately proportional to λtamp0.4; results are given for uranium-235 and plutonium-239 cores surrounded by several commonly used tamper materials.
Sound quality indicators for urban places in Paris cross-validated by Milan data
Authors: Ricciardi Paola , Delaitre Pauline , Lavandier Catherine , Torchia Francesca , Aumond Pierre
Published: October 2015

A specific smartphone application was developed to collect perceptive and acoustic data in Paris. About 3400 questionnaires were analyzed, regarding the global sound environment characterization, the perceived loudness of some emergent sources and the presence time ratio of sources that do not emerge from the background. Sound pressure level was recorded each second from the mobile phone's microphone during a 10-min period. The aim of this study is to propose indicators of urban sound quality based on linear regressions with perceptive variables. A cross validation of the quality models extracted from Paris data was carried out by conducting the same survey in Milan. The proposed sound quality general model is correlated with the real perceived sound quality (72%). Another model without visual amenity and familiarity is 58% correlated with perceived sound quality. In order to improve the sound quality indicator, a site classification was performed by Kohonen's Artificial Neural Network algorithm, and seven specific class models were developed. These specific models attribute more importance on source events and are slightly closer to the individual data than the global model. In general, the Parisian models underestimate the sound quality of Milan environments assessed by Italian people.
Protein ‘drops’ may seed brain disease
Authors: Garber Ken
Published: October 2015

Cellular droplets promote vital biochemistry—but may dangerously solidify
HIV-1 Nef hijacks clathrin coats by stabilizing AP-1:Arf1 polygons
Authors: Shen Qing-Tao , Ren Xuefeng , Zhang Rui , Lee Il-Hyung , Hurley James H.
Published: October 2015

HIV proteins exploit clathrin coats

Clathrin-coated vesicles are involved in the sorting of membrane and cargo at the trans-Golgi network. Clathrin coats exploit adaptor proteins, including AP-1 and AP-2, in selecting their cargoes, assisted by the small membrane-trafficking associated GTPase Arf1. Shen
et al.
were interested in how the HIV-1 Nef protein affected this process. They leveraged a structure solved in the presence of Nef to show that the AP-1:clathrin coat is far more intricately organized than previously thought. Furthermore, Arf1 played a central structural role in these coated vesicles. It seems that HIV-1 Nef hijacks the clathrin pathway to its own ends through very sophisticated structural perturbations.

Science
, this issue p.
10.1126/science.aac5137
Asteroseismology can reveal strong internal magnetic fields in red giant stars
Authors: Fuller Jim , Cantiello Matteo , Stello Dennis , Garcia Rafael A. , Bildsten Lars
Published: October 2015

Stellar oscillations as magnetic probes

Unlike magnetic fields on the surfaces of stars, those within a star have so far remained difficult to observe. Fuller
et al.
have developed a method of delving into the magnetic depths by exploiting the oscillations of red giant stars. A high magnetic field can cause sound waves to become trapped within the central regions of the star, damping certain vibration modes. Using seismological techniques, this suppression can help infer the core magnetic field for several red giants.

Science
, this issue p.
423
Ubiquitin facilitates a quality-control pathway that removes damaged chloroplasts
Authors: Woodson Jesse D. , Joens Matthew S. , Sinson Andrew B. , Gilkerson Jonathan , Salomé Patrice A. , Weigel Detlef , Fitzpatrick James A. , Chory Joanne
Published: October 2015

Quality control one chloroplast at a time

How do plant cells get rid of chloroplasts that are not working as they should? Woodson
et al.
describe a chloroplast quality-control pathway that allows for the selective elimination of individual chloroplasts. Damage by reactive oxygen species during photosynthesis is recognized by a ubiquitin ligase, which marks out damaged chloroplasts for degradation. The findings reveal how cells balance inherently stressful energy production with organelle turnover.

Science
, this issue p.
450
Patrolling monocytes control tumor metastasis to the lung
Authors: Hanna Richard N. , Cekic Caglar , Sag Duygu , Tacke Robert , Thomas Graham D. , Nowyhed Heba , Herrley Erica , Rasquinha Nicole , McArdle Sara , Wu Runpei , Peluso Esther , Metzger Daniel , Ichinose Hiroshi , Shaked Iftach , Chodaczek Grzegorz , Biswas Subhra K. , Hedrick Catherine C.
Published: October 2015

Monocytes block tumor access to the lung

Metastatic cancer is especially hard to treat. In order to find potential new therapeutic targets, scientists are trying to understand the cellular events that promote or prevent metastasis. Hanna
et al.
now report a role for patrolling monocytes in blocking tumor metastasis to the lungs in mice. Tumors in mice engineered to lack patrolling monocytes showed increased metastasis to the lung but not to other tissues. Patrolling monocytes resided in the microvasculature of the lung, where they engulfed tumor material, which may explain how these cells prevent tumors from colonizing the lung.

Science
, this issue p.
985
The dark side of the universe
Dark Matter and the Dinosaurs The Astounding Interconnectedness of the Universe
Lisa Randall
Ecco, 2015. 432 pp.
Authors: Smit Jan , Smit Renske
Published: October 2015

A provocative theory takes readers on a journey through the cosmos
Snapshots of a protein quake
Authors: Neutze Richard
Published: October 2015

Release of CO induces ultrafast collective motions in myoglobin

[Also see Report by

Barends
et al.

]
Beyond known methanogens
Authors: Lloyd Karen
Published: October 2015

DNA sequences from a coal-bed reservoir show that methane can be generated by unexpected microbes

[Also see Report by

Evans
et al.

]
Genome Sequence of
Paenibacillus
sp. Strain FJAT-28004 for the Genome Sequencing Project for Genomic Taxonomy and Phylogenomics of
Bacillus
-Like Bacteria
Authors: Liu Guo-hong , Liu Bo , Wang Jie-ping , Che Jian-Mei , Zhu Yu-Jing , Chen Qian-Qian , Ruan Chuan-Qing
Published: October 2015

Paenibacillus
sp. strain FJAT-28004 is a spore forming and strictly aerobic bacterium. Here, we report the draft 7,479,858-bp genome sequence of
Paenibacillus
sp. FJAT-28004, which will provide useful information for genomic taxonomy and phylogenomics of the genus
Paenibacillus
, as well as for the functional gene mining and application of
Paenibacillus
sp. FJAT-28004.
First Draft Genome Sequence of Salmonella enterica Serovar Gallinarum Strain VTCCBAA614, Isolated from Chicken in India
Authors: Vaid R. K. , Jindal N. , Anand T. , Bera B. C. , Riyesh T. , Virmani N. , Barua S. , Gupta Renu , Mahajan N. K. , Joshi C. G. , Singh R. K.
Published: October 2015

Salmonella enterica
subsp.
enterica
serovar Gallinarum biovar Gallinarum causes fowl typhoid (FT), which results in huge economic losses to poultry farmers in India. We report the draft genome sequence of
Salmonella
biovar Gallinarum strain VTCCBAA614, isolated from a chicken in an FT affected broiler flock.
High-Quality Draft Genome Sequence of Aneurinibacillus migulanus ATCC 9999
T
(DSM 2895), a Gramicidin S-Producing Bacterium Isolated from Garden Soil
Authors: Wang Jie-ping , Liu Bo , Liu Guo-hong , Ge Ci-bin , Xiao Rong-feng , Zheng Xue-fang , Shi Huai
Published: October 2015

Aneurinibacillus migulanus
ATCC 9999
T
(DSM 2895) is a Gram-positive, round-spore-forming, and gramicidin S-producing bacterium. Here, we report the 6.35-Mb high-quality draft genome sequence of
A. migulanus
ATCC 9999
T
, which will provide useful information for the genomic taxonomy and phylogenomics of
Bacillus
-like bacteria.
Draft Genome Sequence of Bacillus murimartini LMG 21005
T
, an Alkalitolerant Bacterium Isolated from a Church Wall Mural in Germany
Authors: Wang Jie-ping , Liu Bo , Liu Guo-hong , Xiao Rong-feng , Zheng Xue-fang , Shi Huai , Ge Ci-bin
Published: October 2015

Bacillus murimartini
LMG 21005
T
is a Gram-positive, spore-forming, and alkalitolerant bacterium isolated from a church wall mural. Here, we report the 4.17-Mb genome sequence of
B. murimartini
LMG 21005
T
, which will accelerate the application of this alkalitolerant bacterium and provide useful information for genomic taxonomy and phylogenomics of
Bacillus
-like bacteria.
Draft Genome Sequence of Cellulolytic and Xylanolytic
Paenibacillus
sp. A59, Isolated from Decaying Forest Soil from Patagonia, Argentina
Authors: Ghio Silvina , Martinez Cáceres Alfredo I. , Talia Paola , Grasso Daniel H. , Campos Eleonora
Published: October 2015

Paenibacillus
sp. A59 was isolated from decaying forest soil in Argentina and characterized as a xylanolytic strain. We report the draft genome sequence of this isolate, with an estimated genome size of 7 Mb which harbor 6,424 coding sequences. Genes coding for hydrolytic enzymes involved in lignocellulose deconstruction were predicted.
Draft Genome Sequence of Streptomyces fradiae olg1-1, a Strain Resistant to Nitrone-Oligomycin
Authors: Vatlin Aleksey A. , Bekker Olga B. , Lysenkova Ludmila N. , Danilenko Valery N.
Published: October 2015

We report a draft genome sequence of
Streptomyces fradiae
olg1-1, a mutant strain derived from the model object
S. fradiae
ATCC 19609, which is resistant to nitrone-oligomycin and has a mutation in the DNA-binding domain of a transcriptional regulator PadR.
Draft Genome Sequence of Pasteurella multocida Isolate P1062, Isolated from Bovine Respiratory Disease
Authors: Abrahante Juan E. , Hunter Samuel S. , Maheswaran Samuel K. , Hauglund Melissa J. , Tatum Fred M. , Briggs Robert E.
Published: October 2015

Here, we report the draft genome of
Pasteurella multocida
isolate P1062 recovered from pneumonic bovine lung in the United States in 1959.
Genome Sequences of Multidrug-Resistant Salmonella enterica Serovar Paratyphi B (dT+) and Heidelberg Strains from the Colombian Poultry Chain
Authors: Donado-Godoy Pilar , Bernal Johan F. , Rodríguez Fernando , Gomez Yolanda , Agarwala Richa , Landsman David , Mariño-Ramírez Leonardo
Published: October 2015

Salmonella enterica
is a pathogen of significant public health importance that is frequently associated with foodborne illness. We report the whole-genome sequences of four multidrug-resistant
Salmonella enterica
serovar Paratyphi B and Heidelberg strains, isolated from the Colombian poultry chain. The isolates contain a variety of antimicrobial resistance genes for aminoglycosides, β-lactams, fluoroquinolones, sulfonamides, tetracycline, and trimethoprim.
Disseminated cryptococcosis in an apparently immunocompetent patient presenting with primary intraventricular haemorrhage
Authors: Pal Partha , Ray Sayantan , Patra Sisir Kumar , Mukherjee Debabrata
Published: October 2015

Disseminated cryptococcosis is uncommon and almost always occurs in HIV-infected patients. However, cryptococcosis can also be found in patients of organ transplantation, in those on disease modifying agents for rheumatological conditions and in patients with underlying immunodeficiency. Cryptococcal infection may occur in an immunocompetent patient, but the pathogenic strain is usuallyCryptococcus gattii, and notC. neoformans.However, disseminated disease, especially cerebral involvement in the form of primary intraventricular haemorrhage, is exceedingly rare. We report a case of disseminated cryptococcosis with cutaneous, cerebral and bone marrow involvement in an HIV-negative, apparently immunocompetent patient. Although the patient did not have the usual immunocompromising diseases, there were clinical signs possibly indicating a weakened immune system. This report highlights the need for awareness of disseminated cryptococcosis among patients with no apparent immunocompromising conditions.
Prolapse of inverted ileal loops through a patent vitellointestinal duct
Authors: Pathak Ashish , Agarwal Nitin , Singh Poonam , Dhaneria Mamta
Published: October 2015

We report a case of a prolapsed patent vitellointestinal duct (PVID) in a 2-month-old girl child who presented with sudden increase in size of a polypoidal lesion into a large, ‘Y’-shaped reddish, prolapsing lesion, discharging gaseous and faecal matter at her umbilicus. The lesion was diagnosed as a prolapse of inverted ileal loops through the PVID. The child had no associated congenital anomalies. A transumbilical exploration was performed, followed by wedge resection and anastomosis. The child tolerated the procedure well and the postoperative course was uneventful. If the omphalomesenteric duct fails to obliterate a range of congenital defects related to the umbilicus, it can become clinically apparent. Meckel's diverticulum is the commonest of these defects but is most often asymptomatic. PVID is the most common symptomatic anomaly of the patent omphalomesenteric duct and requires prompt surgical correction to avoid complications.
Intraosseous cavernous haemangioma of the inferior turbinate
Authors: Goomany Anand , Prowse Simon , Smith Ian
Published: October 2015

Intraosseous cavernous haemangiomas usually occur in the vertebral and calvarial bones, and account for <1% of primary bone tumours. Nasal cavity intraosseous cavernous haemangiomas are extremely rare. We present a case of a 47-year-old woman with an incidental left inferior turbinate mass noted on CT scan for an unrelated pathology. She had no rhinological symptoms other than a 2-year history of left-sided nasal obstruction. Preoperative imaging failed to determine the aetiology of the mass. The lesion, contiguous with the left inferior turbinate, was successfully resected via an endoscopic approach. Histopathological examination of the resected specimen demonstrated a left inferior turbinate intraosseous cavernous haemangioma.
Severe post-influenza (H1N1) encephalitis involving pulvinar nuclei in an adult patient
Authors: Tomás José , Macário Maria Carmo , Gaspar Elsa , Santana Isabel
Published: October 2015

Neurological complications of H1N1 infections are mostly found in children, but rare cases of acute encephalopathy and post-infectious encephalitis such as acute disseminated encephalomyelitis (ADEM) have been described in adults. We report a case of an adult presenting with a progressive and severe encephalopathy that developed after H1N1 respiratory infection resolution. Cerebrospinal fluid (CSF) analysis was normal, including negative PCR for herpes simplex virus, H1N1, influenza B and JC virus, and absent oligoclonal IgG bands in CSF and serum. Initial CT scan was normal, but later MRI showed posterior multifocal leucoencephalopathy with pulvinar sign. The delayed neurological findings together with the ancillary investigation, namely the MRI pattern with both grey and white matter involvement, raised the possibility of a post-infectious process, rather than an acute encephalitis. Despite aggressive immunotherapy, the patient experienced severe neurological sequelae. Early recognition of ADEM manifestations by those dealing with H1N1 infection is important as early immunotherapy may improve the prognosis.
Comparative effectiveness of inhaled corticosteroids for paediatric asthma: protocol for a systematic review and Bayesian network meta-analysis
Authors: Takeuchi Masato , Kano Hirotsugu , Takahashi Kenzo , Iwata Tsutomu
Published: October 2015

Introduction

Use of inhaled corticosteroid (ICS) is the mainstream maintenance therapy for paediatric asthma. Several forms of ICS are available, but the relative effectiveness among ICS has not been well investigated in published, randomised, controlled trials. The paucity of direct comparisons between ICS may have resulted in insufficient estimation in former systematic reviews/meta-analyses. To supplement the information on the comparative effectiveness of ICS for paediatric asthma, we plan to conduct a network meta-analysis that will enable summary of direct and indirect evidence.

Methods and analysis

We will retrieve randomised, controlled trials that examined the effectiveness of ICS for paediatric asthma from the PubMed and Cochrane Central Register of Controlled Trials. After one author scans the title and abstract for eligible studies, two authors will independently review study data and assess the quality of the study. Studies of children (≤18 years old) with chronic asthma or recurrent wheezing episodes will be included if they used ICS for ≥4 weeks. We will define a priori core outcomes and supplemental outcomes of paediatric asthma, including exacerbation, healthcare use and pulmonary function. Studies reporting a minimum of one core outcome will be entered into the systematic review. After the systematic review is performed, extracted data of relevant studies will be synthesised in the Bayesian framework using a random-effects model.

Ethics and dissemination

The results will be disseminated through peer-reviewed publications and conference presentations.

Protocol registration number

UMIN (000016724) and PROSPERO (CRD42015025889).
Patients who discontinued statin treatment: a protocol for cohort study using primary care data
Authors: Vinogradova Yana , Coupland Carol , Brindle Peter , Hippisley-Cox Julia
Published: October 2015

Introduction

Risk thresholds for using statins to prevent cardiovascular disease (CVD) have recently been lowered, so an increasing number of patients are now prescribed these drugs. Although the safety of long-term statin use has been generally established, concerns about the balance of risks and benefits of statins still exist for some medical professionals and patients, and issues concerning their side effects are occasionally widely publicised. This study will report the rates of stopping for statins and also identify any patient groups more likely to stop using statins, so possibly increasing their risk of cardiovascular events.

Methods and analysis

A prospective open cohort study between 1 January 2002 and 30 September 2014 will be based on the general population of people prescribed statins, using records from UK general practices contributing to the Clinical Practice Research Database (CPRD). Participants aged 25–84 years will enter the cohort on the date of their first prescription for a statin and leave on the earliest date of: a cardiovascular event; death; leaving the practice; the last practice upload date or the study end date. If there are no prescriptions within 90 days after the expected finishing date of a prescription, a patient will be defined as a stopper with the discontinuation outcome date as the expected finishing date. Rates of statin discontinuation will be calculated by calendar year, type and dose of statin, age, and morbidities. Cox proportional regression analyses will be run to identify the most important factors associated with discontinuation. Analyses will be run separately for patients without CVD (primary prevention) and with diagnosed CVD (secondary prevention).

Ethics and dissemination

The protocol has been reviewed and approved by Independent Scientific Advisory Committee for MHRA Database Research. The results will be published in a peer-reviewed journal.
STANDARDIZATION AND IMPROVEMENT IN PEDIATRIC CELIAC CARE
Authors: Boyle Brendan , Ediger Tracy , Trout Anne , Wegener Neal , Ramachandran Sandhya , Cummings Mike , Reber Stephanie , Hill Ivor
Published: October 2015

Background

Literature describing practitioner adherence with guidelines for follow up care in patients diagnosed with celiac disease (CD) is limited. NASPGHAN CD guidelines recommend all newly diagnosed patients have repeat serology testing 6 months after diagnosis. Adherence with these recommendations has not been previously described.

Objectives

To review institutional adherence with national guidelines for patients newly diagnosed with celiac disease. We aimed to increase the percentage of patients having repeat serology testing within 9 months of diagnosis from a baseline of 54% to 90% by December 2015.

Methods

Key drivers to improvement included the creation of a reliable, tracking registry and the implementation of a local standard of care. The celiac QI team outlined these divisional expectations through practitioner educational sessions and reporting of practitioner adherence with national guidelines. Improved utilization of administrative staff systematically identified cohorts of patients in need of follow up visits and testing.

Results

Baseline data showed the percentage with repeat testing within 9 months of diagnosis was 54.8% (Q4 2009–Q4 2012). Standardizing care and tracking outcomes increased this percentage to 72.8% (Q1 2013–Q2 2015)-p=0.000. The percentage of patients with a follow up clinic visit within 9 months of diagnosis has increased from a baseline percentage of 82.2% (Q4 2012–Q4 2013) to our current percentage of 96.6% (Q1 2014–Q2 2015)-p=0.000.

Conclusions

Targeted communication with practitioners and families after development of a CD patient registry at our institution allowed structured data capture and significantly improved institutional adherence with national guidelines.

Figure 1

Percentage of patients with serology testing within 9 months of diagnosis.

Figure 2

Percentage of patients with a follow-up GI visit within 9 months of diagnosis.
REDUCING THE INCIDENCE OF CLABSI IN LATIN AMERICAN ICUS: A MULTI-COUNTRY QUALITY IMPROVEMENT COLLABORATIVE. PRELIMINARY RESULTS FROM THE SECOND PHASE
Authors: Arrieta Jafet , Delgado Pedro , Orrego Carola , Giuffre Carolina , Rodríguez Viviana , Elorrio Ezequiel García
Published: October 2015

Background

Central line-associated bloodstream infections (CLABSI) are the leading cause of healthcare-associated bloodstream infections, prolonging hospitalizations, and increasing morbidity, healthcare costs and mortality. The CLABSI rate has been estimated at 7.6 episodes per 1,000 central line days in Latin America. In developing countries, CLABSI are usually the result of a failure to follow evidence-based, standardized health practices.

Objectives

The second phase of the ‘Goodbye Bacteremia' campaign aimed at reducing the CLABSI rate in Latin American Intensive Care Units (ICUs) by 50% or to less than 2 episodes per 1,000 central line days from self-reported baseline within 12 months of the implementation of the campaign.

Methods

Design: Uncontrolled before-and-after CLABSI rates comparison.

Setting: 100 ICUs from six Latin American countries.

Intervention: We used a quality-improvement collaborative to promote the adoption of bundles of care for the insertion and maintenance of central lines, coupled with education through virtual bi-weekly learning sessions, and continuous feedback, from June 2014 to June 2015.

Main outcome measure: CLABSI rate.

Results

The preliminary reduction on the CLABSI rate was 24.34% from a baseline mean of 2.67 to 2.02 at the end of the campaign. The median CLABSI rate was zero throughout the campaign. The mean percentage compliance increased by 49.49% from a baseline of 65.55% to 97.99% at the end of the campaign for the insertion bundle, and by 14.86% from 82.56% to 94.83% for the maintenance bundle.

Conclusions

Evidence-based interventions and multi-country collaborative work contributed to a significant reduction in the incidence of CLABSI in Latin American ICUs.
VULNERABLE CHILDREN AND THEIR CARE QUALITY ISSUES: A DESCRIPTIVE ANALYSIS OF A NATIONAL DATABASE
Authors: Omar Adhnan , Rees Philippa , Evans Huw Prosser , Williams Huw , Cooper Alison , Banerjee Sophie , Hibbert Peter , Makeham Meredith , Parry Gareth , Donaldson Liam , Edwards Adrian , Carson-Stevens Andrew
Published: October 2015

Background

Globally, two in five children are deemed vulnerable by virtue of their physical, psychological and social characteristics. These children are at increased risk of sub-optimal care and disproportionate levels of iatrogenic harm. There remains a paucity of literature describing initiatives for practice improvement for these children.

Objectives

Identify safety reports describing vulnerable children in the England and Wales National Reporting and Learning System (NRLS). Characterise reports in terms of what happened and reported causative issues, in order to identify key change concepts (drivers) and related interventions (change ideas) for improvement.

Methods

An operational definition of ‘vulnerability in children’, including key domains and related keywords (Appendix 1, 2), was empirically informed by a scoping review of the published and grey literature. Relevant reports were descriptively analysed. The free text of the four most frequent incident types (Pareto principle) was discussed by a multi-disciplinary team to identify key concepts for improvement.

Results

2,015 reports were identified involving vulnerable children. The problem areas identified primarily resulted from a fragmentation of care services. This included inefficient transfer of information between primary care services; failure to operationalise care plans in practice; and inconsistent access to healthcare services. Reported causes are outlined in an Ishikawa diagram (figure 1) and summarized in the related driver diagram (figure 2) to mitigate problem areas.

Conclusions

Analysis of patient safety incident reports assisted in the pragmatic identification of key concepts for healthcare professionals to begin more informed discussions about improving the care delivered to vulnerable children.

Figure 1

Ishikawa diagram illustrating causative factors contributing to patient safety incidents.

Figure 2

Driver diagram for improved safety and quality of healthcare of vulnerable children in primary care.

Appendix 1

Process of generating key terms.

Appendix 2

Process of generating key terms (continued).
PREDICTING OUTCOME MEASURE PERFORMANCE THROUGH MONTE CARLO SIMULATION
Authors: Scoville Richard , Ng Manwai , Parry Gareth , Faniyan Abiola , Richman Adam , Evans Arthur
Published: October 2015

Background

Improvement initiatives rely on measures to assess their impact. When outcomes are expressed as percentages, unanticipated changes to the denominator due to complexities and interactions among processes, population and contextual factors can result in measures that fail to register real improvements. For example a pediatric oral health collaborative focused on the incidence of new dental caries as a key measure. Despite uptake of process changes, a prevalence measure failed to register associated improvement in appointment rates (fig 1). Data exploration suggested the measure was confounded with exposure to process changes and recruitment of new patients.

Objectives

To assess whether applying Monte-Carlo simulation can help project designers test the performance of outcome measures under an array of anticipated conditions.

Methods

Data were obtained via a database application installed at each practice which calculated monthly collaborative measures using standard definitions, and produced a file that was uploaded to the collaborative team.

A template with a Monte-Carlo simulation platform was constructed to model a typical practice panel. Random variables modeled patient appointment intervals based on hypothetical subpopulations with varying appointment compliance.

Results

The model tested two alternative definitions of caries incidence, and suggested that a modified definition would more accurately reflect improvements in caries incidence (fig 2).

Based on predictions, the application was modified to incorporate two alternative operational definitions, which were then applied retrospectively by selected practices.

Data using the revised definitions more closely conformed to simulated predictions (fig 3).

Conclusions

Monte Carlo simulation enables advance testing of alternative operational definitions to optimize measure performance.

Figure 1

Original measure.

Figure 2

Simulation results: alternative definitions.

Figure 3

Results: individual team data.
PEDIATRIC CATHETER ASSOCIATED URINARY TRACT INFECTION REDUCTION – AN ACHIEVABLE GOAL
Authors: Fetzer Mike , Humphrey Rhonda , Stack-Simone Stephanie , Stoverock Linda , Groner Jonathan
Published: October 2015

Background

According to the Association for Professionals in Infection Control, urinary tract infections are among the most common of healthcare-associated infections (HAIs), accounting for 25.6 percent of all hospital HAIs. 70%–80% of healthcare-associated UTIs are caused by indwelling urethral catheters. Catheter-associated urinary tract infections (CAUTIs) are associated with increased morbidity, mortality, hospital cost, length of stay, and antimicrobial use.

Objectives

The aim of this project was to decrease our hospital-wide CAUTI rate from 1.3 to <= 0.7 infections per 1000 catheter days.

Methods

A multidisciplinary team implemented a comprehensive strategy to decrease CAUTIs and increase patient safety. Evidence based initiatives focused on catheter insertion, utilization, maintenance, and staff/family education. Staff RNs completed simulated insertion training with return demonstration of competency. Daily Goals were completed to reduce unnecessary catheter use. A maintenance bundle was implemented to ensure standardized practice which focuses on the reduction of perineal bio-burden. Staff huddles were required after each CAUTI to determine root causes.

Results

In 2013–2014, the CAUTI annual rate was 1.3 infections per 1000 catheter days. To date in 2015, the rate is 0.6 infections per 1000 catheter days. The Pediatric Intensive Care Unit has decreased its rate from 2.9 in 2014 to zero in 2015. In addition to reduction in our CAUTI rate, we achieved 193 days between infections.

Conclusions

Published guidelines suggest that implementing evidence based practices can reduce CAUTIs. Our approach resulted in patient care standardization and reduction in patient harm. The reduction strategies used may help positively impact care in other hospitals.

Figure 1Figure 2