bluuebunny/crossref_metadata_2025 huggingface dataset:
Cement Displacement and Pressure Control Using Magneto-Rheological Fluids
Authors: Nair Sriramya D. , Wu Qian , Cowan Mike , van Oort Eric
Published: March 2015

Competent cementing to achieve lasting zonal isolation is a crucial requirement during well construction. Key to achieving a good cementation is proper displacement of drilling fluid out of annular spaces and placement of the cement in them. The viscosity contrast between drilling fluid, spacer(s) and cement as well as centralization of the casing in the wellbore are important variables affecting displacement efficiency. For instance, when the casing is not well-centralized in the wellbore, fluids flow more easily and faster through the wider annular gap, while displacement lags behind and may be incomplete in the narrower gap. Such non-uniform displacement and/or incomplete cement placement can lead to unreliable zonal isolation, which in turn may compromise the productive life of the well.

In this paper, a new cementing technique is presented wherein the rheological properties and the flow direction of the cement slurry can be controlled in real-time to achieve more uniform displacements, even when casing is not optimally centralized. This new technique is based on the principles of magneto-rheology, where an external magnetic field is applied to a cement slurry carrying magnetic particles. In the presence of the magnetic field, the viscoelastic properties of such a modified slurry change instantaneously to cause a stiffening behavior characterized by yield point values that are increased by several orders of magnitude. By varying the intensity and the direction of the magnetic field as well as the dosage of magnetic particles, the flow properties of the slurry can be altered and the flow can be beneficially directed as desired.

The magneto-rheological behavior presents other benefits as well. The instantaneous stiffening effect when a magnetic field is switched on can be exploited to generate temporary top-, bottom- or straddle packers for pressure control, and the specific sensitivity of the magnetic slurry to an external field may be exploited for sensing the quality and integrity of cement sheath over the life of the well. Voids, gaps or cracks in the cemented annulus cause disturbances of magnetic field lines that may be picked up by suitable detectors.
Novel Filter Cake Breaker Design and Successful Use for OHGP Carrier Fluid
Authors: Bulgachev R. , Duran W. , Harpley G. , Hurst G. , Lee R. , Twynam A. , Thay T. , Sookoo A.
Published: March 2015

The Serrette and Savonette gas fields offshore Trinidad will be developed through use of open hole gravel pack (OHGP) completions. This completion type was chosen as the preferred completion technique for sand control for these fields. Due to a wide range of expected fluids densities required, the fluids design considered both monovalent and divalent brine as the base fluid for water-based reservoir drill-in fluid (RDF), completion brine and gravel pack carrier fluid (GPCF). Low pore pressures in the field did not allow applying high drawdowns during backflow of the wells, therefore chemical breaker technology was recommended by the Operator to be included in the fluids package to assist with filter cake removal and wells clean-up. The large pore throats of the formation necessitated the use of a high concentration of coarse sized particles in the RDF for bridging which caused a considerable decrease in retained permeability and potentially plugging of gravel and screen from assurance laboratory testing. High overbalances used during drilling potentially would exascerbate any near wellbore damage from the use of water based fluids.

Most of the commercially available filter cake breakers are compatible only with monovalent brines and the acid precursors in use could not guarantee the low corrosion requirements required, nor result in ideal rheological properties expected from the GPCF over time since Hydroxy-ethyl-cellulose (HEC) was selected as the viscosifier to transport and deposit the gravel.

GPCF with incorporated breaker, composed of a novel chelant compatible with divalent brines and a buffer, was chosen as a solution for the Serrette project. The system was modified for successful use on the Savonette Field. Screening tests were performed by the supplier to obtain an optimized formulation that would satisfy GPCF requirements and logistics. The final formulations were tested and approved at the operator's fluids laboratory. Several wells have been completed using the procedure and products. All have achieved outstanding production rates. The flow initiation pressures measured during wells start-up were noted to be less than those historically seen in the field.

The GPCF with incorporated breaker is believed to have assisted with filter cake removal and well clean-up and also contributed to the fact that the gas requirements from the project have been met. The paper will focus on the development of fluids package for successful implementation in the field to deliver the wells and planned gas production.
Advanced Drilling Engineering Methodology Proves Robust in Preventing Mechanical Lock-up While Deploying Sand-Control Completions Through Complex 3D Drains
Authors: Studer R. , Menand S. , Bourgoin S.
Published: March 2015

In Deep Water development wells, the challenge of successfully positioning the drain through the pay zone is key to meet the economics of a project. The industry today provides a wide range of advanced geosteering solutions that are essential to face such challenges. It is indeed possible to drill tortuous 3D horizontal drains to enhance well placement through the sweetest parts of a reservoir sequences along several thousand meters, the directional bottom hole assembly (BHA) being able to trip in and out of hole without too much issues. The question remains whether the Sand Control (SC) completion string will make it to target depth (TD) at all times? This paper shows that the success of running completion to the intended depth depends critically on the well trajectory surveys spacing (standard versus continuous) taken into account in the torque and drag analysis.

This paper illustrates a recent case of failing to reach TD while running in hole (RIH) a SC completion string in a complex 3D well drilled as part of a major deep water development project in West Africa. The reservoir drain was lost with the completion string stuck 170m above TD and a costly sidetrack had to be drilled to recover the well.

A thorough post-mortem analysis of the case was performed, deploying a unique 3rd party approach based on an advanced drilling engineering methodology, to determine the root causes of the incident:

First, the surveyed well trajectory was reconstructed to precisely define the borehole oscillation along the 12 ¼ in. and 8 ½ in. drilled sections, using an advanced rock and bit-BHA coupling model, Second, simultaneous torque, drag and buckling analysis using stiff-string model were conducted in the reconstructed tortuous well trajectory and compared with standard surveys.

This innovative methodology allowed a precise reproduction of lock-up during the incident while using standard friction factors values (0.22 cased hole & 0.35 open hole) with the stiff-string model, instead of unrealistic 0.6 friction factors using the conventional soft-string solution. The analysis showed the mechanical lock-up of the screens through the tortuous open hole as well as lock-up of drill pipe just above the top of the 9 5/8 in. liner.

Combining both advanced solutions processes is proving very robust in preventing reoccurrence of such an incident. The method can be deployed while drilling, and permits the design of “ad hoc” SC completion strings and centralization to overcome the mechanical hole conditions and ultimately managing successful deployment at an intended depth.
Assessing Casing Wear in the Absence of a Baseline Calliper Log
Authors: Sawaryn S.J. , Pattillo P.D. , Brown C. , Schoepf V.
Published: March 2015

Calliper logs provide valuable information on the shape and wear of casing and tubing strings at various times throughout their operational life. In turn, this information is used to determine the remaining design strength. To clearly distinguish deformation and wear from deviations due to manufacturing tolerance, the calliper measurements can be compared with a baseline log run soon after a tubular string has been run, or with surface inspection data. However, a baseline log may not always be available. This paper addresses these situations and provides an assessment of what useful information can be obtained.

A mathematical model, based on the properties of the discrete Fourier transform is presented to determine the calliper offset centre and underlying tubular ovality from 6 or more equi-angularly spaced calliper readings. The series expansion approximation enables these parameters to be determined as a best fit from raw, un-centred data to a numerical accuracy of approximately 0.01% in a single pass. This is consistent with the accuracy and resolution of the currently available callipers. Complete numerical results from test cases based on exact geometric shapes, such as an offset circle and centred ellipse plus field examples are also included along with implementation notes. The same calculations can also be used to determine the underlying elliptic shape and orientation of an open hole calliper.

In the casing specification API 5CT, internal dimensions are indirectly described in relation to the unloaded casing or tubing OD and wall thickness at surface conditions. The manufacturing tolerances and resulting uncertainties may be significant compared to the wear, but in some cases useful information can be obtained with corrections for downhole tension, temperature and pressure effects. Details of these corrections and a discussion of other sensitivities is also provided.

Such algorithms are usually considered by the service provider to be proprietary and little quantitative material has been published on them or their interpretation. Also, data is often presented to the customer in only centre-corrected form, which greatly restricts future reprocessing. This emphasises the importance of acquiring and retaining the raw data.
Novel Mechanistic Modeling of Cased-Hole Fracpack (CHFP) Well Productivity with Non-Darcy Effects and Fracture-Plane Alignment
Authors: Angeles Renzo , Yin Jichao , Hecker Michael T. , Podust Alex V. , Dares Keith M. , Burdette Jason A. , Huang Hao , Spuskanyuk Alexander
Published: March 2015

Cased-hole fracpacks (CHFP) can deliver high-rate, low-skin completions by creating a highly conductive fracture that extends beyond the perforation tunnels, bypassing near wellbore damage and preventing formation sand production. While the industry has a long history of successful CHFP applications, well performance prediction for this type of completions has remained challenged by complex geometrical (fracture geometry and orientation with respect to arbitrarily deviated wellbores) and multi-physics factors (multiphase flow, turbulence). Most fracpack modeling tools are limited to analytical and simplified reservoir simulation models, which can lead to poor accuracy in quantifying near-wellbore effects, such as non-Darcy pressure drop, particularly important for high-rate gas wells.

In this paper, we propose a new mechanistic approach to incorporate the cased-hole fracpack completion with non-Darcy flow through explicitly meshed perforation tunnels, fractures and rock formation in real dimensions. The fracture is modeled by Enriched Finite Element Method (EFEM), which flexibly accounts for arbitrary fracture geometry and orientation while enabling multi-physics effects, impact of perforation/gravel packing damage and perforation-fracture communication uncertainty on deviated well productivities.

The proposed approach is validated using (1) analytical and numerical models, and (2) two Gulf of Mexico (GOM) CHFP wells, one vertical and one deviated; where skins measured from step-rate tests were history-matched to longitudinal and transverse fracture models. We also introduce the concept of fracture neighborhood width to account for perforation performance relative to its alignment with fracture opening and orientation. Finally, the new approach is used to predict the deliverability of a high-rate, high-pressure gas condensate well. Non-Darcy effects, condensate banking effects, perforation gravel packing, and geological model uncertainties are included in predicting the well production.
Modeling Drillstring Magnetic Interference of Wellbore Surveys Using Damagnetizing Factors
Authors: Phillips W. , Aklestad D.
Published: March 2015

Accurate directional borehole guidance requires Bottom Hole Assembly (BHA) non-magnetic spacing of Measurement While Drilling (MWD) systems from surrounding steel components. This is required to limit the magnetic interference and associated azimuth measurement error to acceptable levels.

The current industry method of calculating the Estimated Drillstring Interference (EDI) on MWD magnetometers and the resulting azimuth error produced, are largely based on published material from the late 1970's to early 1980's. The current method models components as magnetic dipoles requiring the knowledge or “guess” of the pole strength of the BHA component and combination of components.

Technological advances in drillstring design and complexity have rendered these methods inadequate. This inadequacy is due to the lack of knowledge of the pole strength information for modern components and/or the unlimited configurations of components, and the limited and simplified BHA configurations normally available in supporting software tools where the EDI calculation is performed.

This paper presents the theory and method of computing the EDI using demagnetizing factors of a prolate spheroid. A worked example of this method is shown to illustrate its implementation with a comparison of the results to published dipole method examples as a reference.

The operational advantages of the demagnetizing factor method are presented showing more consistency in calculation, elimination of BHA complexity limits, ease of computer implementation and system integration, and elimination of subjective and inconsistent selection of component pole strengths used in the dipole method, this providing a means of EDI calculation standardization across the industry.
Integration of Remote Sensing and Crop Modeling for the Early Assessment of Durum Wheat Harvest at the Field Scale
Authors: Orlando Francesca , Marta Anna Dalla , Mancini Marco , Motha Ray , Qu John J. , Orlandini Simone
Published: March 2015

In the Mediterranean, durum wheat is one of the major crops, but a high variability of grain yield and protein concentration (GPC) prevents an adequate agronomic planning at the farm or consortium level. Although there are many studies on monitoring of crop production and early prediction of yields, little has been done at the local scale. The aim of this study was to assess simplified integration algorithms (SIAs) for integrating remote sensing information with a crop model, to forecast the GPC and grain yield at the field scale. To this end, the CERES‐Wheat model was run to simulate the seasonal average of grain yield (AVE) and GPC in Val d’ Orcia (Tuscany Region, Italy) during the 2009–2010 and 2010–2011 growing seasons. The performances of different vegetation indices from MODIS imagery in harvest forecasting were assessed and compared. The SIA formulation was based on the simulated AVE and GPC, and on their spatialization in relation to the intraannual variability between the fields described by vegetation indices. The simulated AVE traced the observed trend. The fraction of absorbed photosynthetically active radiation (fPAR) was the best index in describing grain yield, and the related SIA showed at validation good performance at the field scale (r2 = 0.74). Conversely, the SIA was unable to predict GPC due to the low performance of CERES‐Wheat in capturing the interannual variability and to the failure of the fPAR in describing the GPC interfields variability at intermediate canopy reflectance values.
Desulfurization performance of biotrickling filter on the removal of flue gas adsorbent produced by dual-alkali flue gas desulfurization process
Authors: Zheng Tianlong , Wang Li , Wang Jianhua , Xue Niantao , Wang Qunhui
Published: March 2015

A biotrickling filter (BTF) was used to investigate the elimination of flue gas adsorbent containing sulfite, sulfate, and hydrosulfate; it was undertaken to replace the regeneration step of dual-alkali flue gas desulfurization. Sulfate-reducing bacteria (SRB) isolated from landfill leachate were inoculated, and overall desulfurization performance as well as impact resistance was evaluated. The results showed that an efficient SRB could reduce the start-up time to 1 h, which is one third of that required for initial condition, for a sulfite removal efficiency above 80%. Further, the sulfite removal efficiency rose to 98% in 3.9 h with the lower packing load of 5.56 kg SO32−-S/(m3d), and in 6.4 h for 6.37 kg SO32−-S/(m3d). In contrast, 85% removal efficiency in 5 h for sulfate and 98% removal efficiency in 0.5 h for hydrosulfite were obtained when the packing loads were 0.95 kg SO42−-S/(m3d) and 1.76 kg HSO3−-S/(m3 d), respectively. Moreover, the BTF could quickly restore after impact shock, such as, 0.5 h restoration time for initial pH which varied from 4.5 to 6.5, 6 d for 27 d shutdown behavior, and 4 d for 5 h high temperature shock of 85 °C. Therefore, the BTF system was an effective method for flue gas adsorbent treatment.
Validation of the Goreangab Reclamation Plant in Windhoek, Namibia against the 2008 Australian Guidelines for Water Recycling
Authors: Law Ian B. , Menge Jurgen , Cunliffe David
Published: March 2015

Australia has had Guidelines in place for water recycling (for all uses other than the augmentation of drinking water supplies) since 2006. These Guidelines were extended to cover potable reuse in May 2008 and have been applied to two potable reuse projects in Australia – one a trial plant in Perth, Western Australia and the second for a large AUD$2.6 × 109 scheme in Brisbane, Queensland. All reclamation plants in Australia must be ‘validated’ against the Australian Guidelines for Water Recycling prior to being put into operation. The majority of advanced reuse schemes incorporate the dual membrane process – microfiltration or ultrafiltration followed by reverse osmosis (RO) – in the treatment trains and while this membrane based treatment has been shown to produce a very high quality of product water, it does come at a cost and there is renewed interest in alternative treatment technologies that offer cost savings and are more sustainable. This paper uses data gathered in Australia from a range of advanced reclamation plants, as well as design and actual performance criteria from the Goreangab Plant, to ‘validate’ the latter and, given the longevity of the Windhoek direct potable reuse experience, lend support to more serious consideration of non-RO based plants for potable reuse applications.
Contemporary design, operation, and monitoring of potable reuse systems
Authors: Drewes J. E. , Khan S. J.
Published: March 2015

Water scarcity driven by population growth, lack of conventional supplies, and climate change impacts have resulted in increasing interest worldwide in drinking water augmentation using treated wastewater effluents. Potable reuse can occur indirect or direct, but is also practiced in many places as ‘de facto reuse’, where upstream wastewater discharge occurs to drinking water supplies. With this increasing recognition of potable reuse, there is very limited guidance and standardization for proper design and operation of potable reuse schemes that is protective of public health. This study provided guidance on contemporary approaches for the design, operation, and monitoring of potable reuse schemes, including source water characterization and source control approaches; linking water quality treatment performance goals to health risks; risk mitigation strategies including the design principles of multiple barriers for microbial and chemical contaminants; assessing system reliability and fail-safe design approaches; and, finally, monitoring strategies for process performance and compliance.
Internal Control Quality and Credit Default Swap Spreads
Authors: Tang Dragon Yongjun , Tian Feng , Yan Hong
Published: March 2015

SYNOPSIS

This paper presents the first study on the effects of internal control quality on derivatives pricing. Specifically, we utilize data from the credit default swap (CDS) transactions of well-monitored companies to examine the relationship between the quality of internal control and the cost of debt. CDS data are advantageous for the study of this relationship because CDS contracts are comparatively more homogeneous, standardized, and liquid than either bank loans or public bonds. We find that, all else being equal, companies experiencing internal control material weakness (MW) exhibit higher CDS spreads than companies with effective internal control. Moreover, the MW effect on CDS spreads is more pronounced for company-level MWs than for less severe, account-specific MWs. We also document that CDS spreads increase around the filings of MWs. Furthermore, the deterioration of internal control quality is related to increases in CDS spreads. Finally, short-maturity CDS spreads are more affected by MWs than are long-maturity CDS spreads.

JEL Classifications: M41; G32; K22.

Data Availability: The data are available from public sources.
Accounting as Personal Apology
Authors: Killian Larita J.
Published: March 2015

What is the role of accounting? Typically, accounting is viewed as a technology to inform business decisions, such as allocation of economic resources within the marketplace. In contrast, public interest scholars emphasize the social role of accounting. For example, accounting mediates relationships among various parties, impacts social outcomes, and justifies the distribution of economic rewards. This paper contributes to the public interest perspective by exploring the origin of double-entry accounting (DEA) as a form of personal apologia. To develop the thesis that DEA originated as a form of personal apology, this paper draws from modern and medieval scholars. During the medieval period, profit seeking and markets were deeply suspect and, thus, medieval merchants occupied a precarious social and moral position. The Catholic Church was active in determining the “just price” for goods. Personal morality and just, balanced relationships were primary factors in the development of DEA. Confession and penance, sacraments of the Catholic Church, may have provided the model. The thesis that DEA originated as a form of personal apology is plausible. The contemporary, widespread use personal carbon-offset accounting (PCOA) illustrates that accounting retains the power to help construct the moral self and to mediate the individual's status within the community.
Adipose Tissue–Derived Stem Cells From Obese Subjects Contribute to Inflammation and Reduced Insulin Response in Adipocytes Through Differential Regulation of the Th1/Th17 Balance and Monocyte Activation
Authors: Eljaafari Assia , Robert Maud , Chehimi Marwa , Chanon Stephanie , Durand Christine , Vial Guillaume , Bendridi Nadia , Madec Anne-Marie , Disse Emmanuel , Laville Martine , Rieusset Jennifer , Lefai Etienne , Vidal Hubert , Pirola Luciano
Published: March 2015

Obesity, through low-grade inflammation, can drive insulin resistance and type 2 diabetes. While infiltration of adipose tissue (AT) with mononuclear cells (MNCs) is well established in obesity, the functional consequences of these interactions are less understood. Herein, we cocultured human adipose-derived stem cells (ASCs) from obese individuals with MNCs and analyzed their reciprocal behavior. Presence of ASCs 1) enhanced interleukin (IL)-17A secretion by Th17 cells, 2) inhibited γ-interferon and tumor necrosis factor α secretion by Th1 cells, and 3) increased monocyte-mediated IL-1β secretion. IL-17A secretion also occurred in stromal vascular fractions issued from obese but not lean individuals. Th17 polarization mostly depended on physical contacts between ASCs and MNCs—with a contribution of intracellular adhesion molecule-1—and occurred through activation of the inflammasome and phosphatidylinositol 3-kinase pathways. ASCs favored STAT3 over STAT5 transcription factor binding on STAT binding sites within the IL-17A/F gene locus. Finally, conditioned media from activated ASC-MNC cocultures inhibited adipocyte differentiation mRNA markers and impaired insulin-mediated Akt phosphorylation and lipolysis inhibition. In conclusion, we report that obese- but not lean-derived ASCs induce Th17 promotion and monocyte activation. This proinflammatory environment, in turn, inhibits adipogenesis and adipocyte insulin response. The demonstration of an ASC-Th17-monocyte cell axis reveals a novel proinflammatory process taking place in AT during obesity and defines novel putative therapeutic targets.
Factors Associated with the Development and Remission of Allergic Diseases in an Epidemiological Survey of High School Students in Japan
Authors: Tokunaga Takahiro , Ninomiya Takahiro , Osawa Yoko , Imoto Yoshimasa , Ito Yumi , Takabayashi Tetsuji , Narita Norihiko , Kijima Akiko , Murota Hiroyuki , Katayama Ichiro , Fujieda Shigeharu
Published: March 2015

Background

Allergic diseases are an important health problem for children and adults. It is important to know how allergic diseases develop and remit from infancy to adolescence. Early intervention is effective in treating allergic diseases.

Objective

We performed a large-scale questionnaire survey of high school students in Fukui Prefecture, Japan, and analyzed the factors associated with the development and remission of allergic diseases.

Methods

A total of 21,802 students participated in the epidemiologic survey, and the valid response rate was 89.3% (19,461). We applied an inverse probability weighting method with propensity scores.

Results

The present prevalence rate of allergic rhinitis (AR) was 19.2%. The remission rate of AR was 15.3%. Only children and firstborns had a significantly higher risk of developing symptoms of allergic diseases [only child: AR, 1.37; bronchial asthma (BA), 1.30; food allergy (FA), 1.33 and firstborn: AR, 1.38; BA, 1.10]. Constipation was an associated factor for development of atopic dermatitis (AD) (1.17) and AR (1.17), regular intake of lactic acid bacteria was not an associated factor for development of allergic diseases but was a factor for remission of AD (1.22). Hypohidrosis was an associated factor for development of AD (1.25). High academic performance was an associated factor for development of AR (1.20) but was a negative factor for development of BA (0.89). The values in parentheses are significant adjusted odds ratios.

Conclusion

This epidemiologic survey showed that the hygiene hypothesis and intestinal bacterial flora might influence the development of symptoms and remission of allergic diseases.
Maternofetal Transfer of Antibodies and the Influence of Maternal Atopic Status on the Neonate
Authors: Yu Zizhong , Chen Jianjun , Zhang Quanming , Yin Xiaoyan , Wang Yanjun , Fu Junmei , Zou Li , Kong Weijia
Published: March 2015

Background

Epidemiologic evidence has shown that sensitization of allergic diseases develops early in life, even before birth. The gestational environment, including maternal atopic status and transplacentally transferred antibodies to allergens, may be of importance in the sensitization process.

Objective

To investigate maternofetal transfer of antibodies and the influence of maternal atopic status on the neonatal immune response.

Methods

Fifty-seven healthy pregnant women who underwent elective cesarean section (ECS) were recruited. Total and specific IgE (Phadiatop) levels in cord blood (CB) and maternal blood (MB) were determined using the ImmunoCAP assay. MB- and CB-specific IgG1 and IgA1 antibodies against ovalbumin and house dust mite were analyzed by enzyme linked immunosorbent assay. The cytokines, interleukin (IL)-13, interferon (IFN)-γ, and IL-10 in the supernatant of cultured CB mononuclear cells were quantified by enzyme linked immunosorbent assay. Two subgroups were defined based on the maternal levels of specific IgE (atopic group, Phadiatop IgE more than or equal to 0.35 kilo international units of allergen-specific antibody (KUA)/L; nonatopic group, Phadiatop IgE less than 0.35 KUA/L).

Results

Although total IgE was detectable in all MB samples, it could only be detected in 7% (4/57) of the CB samples. Specific IgE was detectable in all MB samples but undetectable in all CB samples. There was no correlation of total IgE between mothers and their neonates. The concentrations of IL-10, IL-13, and allergen-specific IgG1 and IgA1 in the CB samples did not differ significantly between the atopic and nonatopic groups. IFN-γ was undetectable in the CB samples.

Conclusions

Maternal IgE cannot be transferred to the child in utero. Maternal atopic status has no significant effect on neonatal immune responses.
A Pilot Study of the Self-Administered Computerized Olfactory Testing System
Authors: Jiang Rong-San , Liang Kai-Li
Published: March 2015

Background

The Self-Administered Computerized Olfactory Testing System (SCOTS) was developed recently to perform the olfactory threshold test under computer control. The aim of this study was to evaluate the validity and test-retest reliability of the SCOTS.

Methodology

A total of 180 subjects were tested for olfactory thresholds using an odor detection threshold test and the SCOTS. There were 60 normosmic volunteers, 60 hyposmic patients, and 60 anosmic patients. Among them, 30 normosmic subjects were retested with the SCOTS at least 1 day after the first test occasion. The olfactory threshold test and retest results from the SCOTS were compared.

Results

The mean olfactory threshold attained from the SCOTS was -5.48 for normosmic subjects, -3.18 for hyposmic patients, and -2 for anosmic patients. The olfactory thresholds among the normosmic, hyposmic, and anosmic patients were significantly different (p < .001). The correlation coefficient between the olfactory thresholds of an odor detection threshold test and the SCOTS was 0.809 (p < .001). The test-retest correlation for the SCOTS-based olfactory thresholds was strong (r = 0.671; p < .001).

Conclusion

Our results show that on the basis of its validity and test-retest reliability, the SCOTS was appropriate for self-administered tests of the olfactory threshold.
Pavement Condition Monitoring with Crowdsourced Connected Vehicle Data
Authors: Dennis Eric Paul , Hong Qiang , Wallace Richard , Tansil William , Smith Matt
Published: March 2015

The Michigan Department of Transportation (DOT) is interested in new technologies to improve transportation asset management (TAM) practices. A central component of TAM is pavement condition and performance assessment. To investigate methods to improve TAM data collection, the Michigan DOT and the Center for Automotive Research researched the potential for connected vehicle data to contribute to pavement condition and performance assessment. This effort included the review, critical analysis, and synthesis of several research reports and pilot projects to determine feasible methods of using connected vehicle data for pavement condition and performance assessment. The scope of connected vehicle data was defined to include data collected by sensors installed on consumer available vehicles and smartphones. The technology to allow for data capture from embedded vehicle systems and smartphones was established, but implementing such practices into TAM had not yet proved to be practical. One possibility for effective pavement data collection was to employ crowdsourcing, with the use of numerous probe vehicles. Crowdsourcing was not a common practice in pavement condition assessment. Using crowdsourced data in existing TAM programs may require innovative methods of data collection, processing, and management. This report concluded that by focusing on consumer available equipment and crowdsourced data, new connected vehicle data–based pavement condition metrics could be used for TAM in 3 to 5 years.
An unusual presentation of pediatric osteoblastoma in a patient with Klippel-Trenaunay-Weber syndrome: case report
Authors: Wallace Scott A. , Ignacio Romeo C. , Klugh Arnett , Gates Gregory , Henry Marion C. W.
Published: March 2015

Osteoblastoma is an uncommon primary bone tumor that usually presents as a painful lesion in a long bone or in the spine. Osteoblastoma has been reported only twice in the literature in conjunction with systemic fibromatosis. The authors report the case of an 8-year-old girl with suspected Klippel-Trenaunay-Weber syndrome, a rare syndrome of systemic fibromatosis, who presented with a painless thoracic rib lesion that was found to be an osteoblastoma.
Temporal trends of intraventricular hemorrhage of prematurity in Nova Scotia from 1993 to 2012
Authors: Radic Julia A. E. , Vincer Michael , McNeely P. Daniel
Published: March 2015

OBJECT

Intraventicular hemorrhage (IVH) and posthemorrhagic hydrocephalus (PHH) are common in premature newborns. The epidemiology of these conditions has been described, but selection bias remains a significant concern in many studies. The goal of this study was to review temporal trends in the incidence of IVH, PHH, and shunt surgery in a population-based cohort of very preterm infants with no selection bias.

METHODS

All very preterm infants (gestational age ≥ 20 and ≤ 30 weeks) born from 1993 onward to residents of Nova Scotia were evaluated by the IWK Health Centre's Perinatal Follow-Up Program, and were entered in a database. Infants born to residents of Nova Scotia from January 1, 1993, to December 31, 2012, were included in this study. The incidences of IVH, PHH, and shunt surgery were calculated, basic demographic information was described, and chi-square test for trends over time was determined.

RESULTS

Of 1334 successfully resuscitated very preterm infants who survived to their initial screening ultrasound, 407 (31%) had an IVH, and 149 (11%) had an IVH Grade 3 or 4. No patients with IVH Grade 1 or 2 developed PHH. The percentage of very preterm infants with IVH Grade 3 or 4 has significantly increased over time (p = 0.013), as have the incidence of PHH and shunt surgery (p = 0.001 and p = 0.011, respectively) in infants with Grade 3 or 4 IVH. The proportion of patients with PHH receiving a shunt has not changed over time (p = 0.813).

CONCLUSIONS

The increasing incidence of high-grade IVH—and PHH and shunt surgery in infants with high-grade IVH—over time is worrisome. This study identifies a number of associated factors, but further research to identify preventable and treatable causal factors is warranted.
Temperature distribution and thermal anomalies along a flowline of the Greenland ice sheet
Authors: Harrington Joel A. , Humphrey Neil F. , Harper Joel T.
Published: March 2015

Englacial and basal temperature data for the Greenland ice sheet (GrIS) are sparse and mostly limited to deep interior sites and ice streams, providing an incomplete representation of the thermal state of ice within the ablation zone. Here we present 11 temperature profiles at five sites along a 34 km east–west transect of West Greenland. These profiles depict ice temperatures along a flowline and local temperature variations between closely spaced boreholes. A temperate basal layer is present in all profiles, increasing in thickness in the flow direction, where it expands from ∼3% of ice height furthest inland to 100% at the margin. Temperate thickness growth is inconsistent with modeled heat contributions from strain heating, heat conduction, and vertical extension of the temperate layer. We suggest that basal crevassing, facilitated by water pressures at or near ice overburden pressure, is responsible for the large temperate ice thicknesses observed. High-temperature kinks at 51–85 m depth are likely remnants from the thermal influence of partially water-filled crevasses up ice sheet. Steep horizontal temperature gradients between closely grouped boreholes suggest the recent thermal influence of a moulin. These profiles demonstrate the ability of meltwater to rapidly alter ice temperatures at all depths within the ablation zone.
Characterizing the Water Balance of the Sooke Reservoir, British Columbia over the Last Century
Authors: Werner Arelia , Prowse Terry , Bonsal Barrie
Published: March 2015

Infrastructure such as dams and reservoirs are critical water-supply features in several regions of the world. However, ongoing population growth, increased demand and climate variability/change necessitate the better understanding of these systems, particularly in terms of their long-term trends. The Sooke Reservoir (SR) of British Columbia, Canada is one such reservoir that currently supplies water to ~300,000 people, and is subject to considerable inter and intra-annual climatic variations. The main objectives of this study are to better understand the characteristics of the SR through an in-depth assessment of the contemporary water balance when the basin was intensively monitored (1996–2005), to use standardized runoff to select the best timescale to compute the Standard Precipitation (SPI) and Standard Precipitation Evaporation Indices (SPEI) to estimate trends in water availability over 1919 to 2005. Estimates of runoff and evaporation were validated by comparing simulated change in storage, computed by adding inputs and subtracting outputs from the known water levels by month, to observed change in storage. Water balance closure was within ±11% of the monthly change in storage on average when excluding months with spill pre-2002. The highest evaporation, dry season (1998) and lowest precipitation, wet season (2000/2001) from the intensively monitored period were used to construct a worst-case scenario to determine the resilience of the SR to drought. Under such conditions, the SR could support Greater Victoria until the start of the third wet season. The SPEI and SPI computed on a three-month timescale had the highest correlation with the standardized runoff, R2 equaled 0.93 and 0.90, respectively. A trend toward drier conditions was shown by SPEI over 1919 to 2005, while moistening over the same period was shown by SPI, although trends were small in magnitude. This study contributes a validated application of SPI and SPEI, giving more credit to their trends and estimated changes in drought.
Study on the Correlation between Microstructure Corrosion and Wear Resistance of Ag-Cu-Ge Alloys
Authors: Cusma Antonio , Sebastiani Marco , De Felicis Daniele , Basso Andrea , Bemporad Edoardo
Published: March 2015

In this work, a morphological and structural characterization of a ternary Ag-Cu-Ge alloy of known composition was performed with the aim of evaluating how the passivation parameters (time and temperature) influence the morphological features of the material surface. A nanomechanical characterization was performed in order to correlate the morphology and microstructure of the alloy with its tarnish, wear, and scratch resistance. It was found that the addition of germanium to the alloy not only provides the material with tarnish and fire-stain resistance, but it also improves the scratch and wear resistance owing to the formation of a dense and stable thin oxide layer.
Evolutionary Dynamics in Gene Networks and Inference Algorithms
Authors: Aguilar-Hidalgo Daniel , Lemos María , Córdoba Antonio
Published: March 2015

Dynamical interactions among sets of genes (and their products) regulate developmental processes and some dynamical diseases, like cancer. Gene regulatory networks (GRNs) are directed networks that define interactions (links) among different genes/proteins involved in such processes. Genetic regulation can be modified during the time course of the process, which may imply changes in the nodes activity that leads the system from a specific state to a different one at a later time (dynamics). How the GRN modifies its topology, to properly drive a developmental process, and how this regulation was acquired across evolution are questions that the evolutionary dynamics of gene networks tackles. In the present work we review important methodology in the field and highlight the combination of these methods with evolutionary algorithms. In recent years, this combination has become a powerful tool to fit models with the increasingly available experimental data.
Design of a Flow Visualisation Framework
Authors: Edmunds Matthew , Tong Chao , Laramee Robert
Published: March 2015

Research software often consists of individual, isolated prototype applications. Small proof of concept applications are usually enough for demonstrating new algorithms. However, the unification of new research algorithms into a cohesive software framework has advantages. Adding new features to an existing pipeline reduces implementation overhead. The researcher is more able to compare and contrast existing or previous work with new research. Utilizing previously implemented techniques, researchers are able to combine visualization options in new ways that typical research prototypes cannot. The software application can be made available to the domain expert for evaluation and future use. These goals are in part realized by utilizing recent advancements in game design technology and by leveraging features available with recent graphics hardware. Described is the design of a feature-rich flow visualization software framework in more detail than a typical research paper. In contrast to most research prototypes, the system we present handles real-world simulation datasets by interfacing directly with the commercial package called tecplot. We present a description of our system in detail, whereas previously published work focuses on the research contribution. The effectiveness and scalability of the approach is also discussed.
Entropic Measures of Complexity of Short-Term Dynamics of Nocturnal Heartbeats in an Aging Population
Authors: Makowiec Danuta , Kaczkowska Agnieszka , Wejer Dorota , Żarczyńska-Buchowiecka Marta , Struzik Zbigniew
Published: March 2015

Two entropy-based approaches are investigated to study patterns describing differences in time intervals between consecutive heartbeats. The first method explores matrices arising from networks of transitions constructed following events represented by a time series. The second method considers distributions of ordinal patterns of length three, whereby patterns with repeated values are counted as different patterns. Both methods provide estimators of dynamical aspects of short-term heartbeat signals obtained from nocturnal Holter electrocardiogram (ECG) recordings of healthy people of different ages and genders. The deceleration capacity, arising from the adjacency matrix of the network, and the entropy rate, resulting from the transition matrix of the network, are also calculated, and both significantly decay with aging. As people age, the permutation entropy grows, due to the increase in patterns with repeated values. All of these estimators describe in a consistent way changes in the beat-to-beat heart period dynamics caused by aging. An overall slowing down of heart period changes is observed, and an increase of permutation entropy results from the progressive increase of patterns with repeated values. This result points to the sympathetic drive becoming dominant in cardiac regulation of nocturnal heart rate with age.
New TA Index-Based Rollover Prevention System for Electric Vehicles
Authors: Liu Xiang , Xu Min , Li Mian
Published: March 2015

In addition to clean transportation and energy savings, electric vehicles can inherently offer better performance in the field of active safety and dynamic stability control, thanks to the superior fast and accurate control characteristics of electric motors. With the novel wheel status parameter TA for electric vehicles proposed by the authors in an earlier publication, a new TA index (TAI)-based rollover prevention method is presented in this paper to improve the driving performance of EVs equipped with in-wheel motors. A three-level electric vehicle control structure is used to analyze the effective control steps for rollover prevention with the newly proposed TAI method. The simulation is conducted using an in-house developed electric vehicle dynamic model. The simulation results prove the feasibility of using TAI to detect rollover. The experiment uses an electric vehicle equipped with four in-wheel motors in the authors’ research lab. The vehicle parameter and performance data are imported to CarSim, which is industrial standard vehicle dynamic analysis software to run the rollover test. The experimental results also demonstrate that TAI is an effective method of rollover prevention.
Integration of a Water Scrubbing Technique and Two-Stage Pressurized Anaerobic Digestion in One Process
Authors: Lemmer Andreas , Chen Yuling , Wonneberger Anna-Maria , Graf Frank , Reimert Rainer
Published: March 2015

Two-stage pressurized anaerobic digestion is a promising technology. This technology integrates in one process biogas production with upgrading and pressure boosting for grid injection. To investigate whether the efficiency of this novel system could be further increased, a water scrubbing system was integrated into the methanogensis step. Therefore, six leach-bed reactors were used for hydrolysis/acidification and a 30-L pressurized anaerobic filter operated at 9 bar was adopted for acetogenesis/methanogenesis. The fermentation liquid of the pressurized anaerobic filter was circulated periodically via a flash tank, operating at atmospheric pressure. Due to the pressure drop, part of dissolved carbon dioxide was released from the liquid phase into the flash tank. The depressurized fermentation liquid was then recycled to the pressurized reactor. Three different flow rates (0 L·day−1, 20 L·day−1 and 40 L·day−1) were tested with three repetitions. As the daily recycled flashed liquid flow was increased from 0 to 40 L, six times as much as the daily feeding, the methane content in the biogas increased from 75 molar percent (mol%) to 87 mol%. The pH value of the substrate in the methane reactor rose simultaneously from 6.5 to 6.7. The experimental data were verified by calculation.
Attentional Distraction during Exercise in Overweight and Normal-Weight Boys
Authors: Deforche Benedicte , De Bourdeaudhuij Ilse
Published: March 2015

The purpose of this study was to investigate the effect of attentional distraction on field running distance and activity intensity during an exercise session in normal-weight and overweight youngsters and to investigate potential mediators. Fifty-three 12–14 yr-old boys participated twice in a 12-min running test and a 20-min exercise session, once with attentional distraction (by listerning to music) and once without distraction (counterbalanced randomised controlled design). At the end of the endurance test running distance was recorded. During the exercise session activity intensity was assessed by accelerometers. After each experiment, rate of perceived exertion (RPE) was estimated and seven questions were asked about how participants experienced the experiment. Both overweight and normal-weight boys ran further during the running test with music (p < 0.05) and this effect was mediated by a decrease in feelings of annoyance. During the exercise session with music, both overweight and normal-weight boys exercised less at low and high intensity and more at moderate and very high intensity (p < 0.01) and this effect was mediated by a decrease in RPE. We can conclude that attentional distraction has a positive effect on running distance on a field endurance test and on activity intensity during an exercise session through different mechanisms in both overweight and normal-weight boys.