bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of an Expenditure Cap on Low‐Income Seniors' Drug Use and Spending in a State Pharmacy Assistance Program
Authors: Bishop Christine E. , Ryan Andrew M. , Gilden Daniel M. , Kubisiak Joanna , Thomas Cindy Parks
Published: March 2009

Objective. To estimate the impact of a soft cap (a ceiling on utilization beyond which insured enrollees pay a higher copayment) on low‐income elders' use of prescription drugs.

Data Sources and Setting. Claims and enrollment files for the first year (  June 2002 through May 2003) of the Illinois SeniorCare program, a state pharmacy assistance program, and Medicare claims and enrollment files, 2001 through 2003. SeniorCare enrolled non‐Medicaid‐eligible elders with income less than 200 percent of Federal Poverty Level. Minimal copays increased by 20 percent of prescription cost when enrollee expenditures reached $1,750.

Research Design. Models were estimated for three dependent variables: enrollees' average monthly utilization (number of prescriptions), spending, and the proportion of drugs that were generic rather than brand. Observations included all program enrollees who exceeded the cap and covered two periods, before and after the cap was exceeded.

Principle Findings. On average, enrollees exceeding the cap reduced the number of drugs they purchased by 14 percent, monthly expenditures decreased by 19 percent, and the proportion generic increased by 4 percent, all significant at p<.01. Impacts were greater for enrollees with greater initial spending, for enrollees without one of five chronic illness diagnoses in the previous calendar year, and for enrollees with lower income.

Conclusions. Near‐poor elders enrolled in plans with caps or coverage gaps, including Part D plans, may face sharp declines in utilization when they exceed these thresholds.
Soft tissues healing at immediate transmucosal implants placed into molar extraction sites with buccal self‐contained dehiscences. A 12‐month controlled clinical trial
Authors: Siciliano V. Iorio , Salvi G. E. , Matarasso S. , Cafiero C. , Blasi A. , Lang N. P.
Published: March 2009

Aim: To assess soft tissues healing at immediate transmucosal implants placed into molar extraction sites with buccal self‐contained dehiscences.

Material and methods: For this 12‐month controlled clinical trial, 15 subjects received immediate transmucosal tapered‐effect (TE) implants placed in molar extraction sockets displaying a buccal bone dehiscence (test sites) with a height and a width of ≥3 mm, respectively. Peri‐implant marginal defects were treated according to the principles of Guided Bone Regeneration (GBR) by means of deproteinized bovine bone mineral particles in conjunction with a bioresorbable collagen membrane. Fifteen subjects received implants in healed molar sites (control sites) with intact buccal alveolar walls following tooth extraction. In total, 30 TE implants with an endosseous diameter of 4.8 mm and a shoulder diameter of 6.5 mm were used. Flaps were repositioned and sutured, allowing non‐submerged, transmucosal soft tissues healing. At the 12‐month follow‐up, pocket probing depths (PPD) and clinical attachment levels (CAL) were compared between implants placed in the test and the control sites, respectively.

Results: All subjects completed the 12‐month follow‐up period. All implants healed uneventfully, yielding a survival rate of 100%. After 12 months, statistically significantly higher (P<0.05) PPD and CAL values were recorded around implants placed in the test sites compared with those placed in the control sites.

Conclusions: The findings of this controlled clinical trial showed that healing following immediate transmucosal implant installation in molar extraction sites with wide and shallow buccal dehiscences yielded less favorable outcomes compared with those of implants placed in healed sites, and resulted in lack of ‘complete’ osseointegration.
Assessment of infrazygomatic bone depth for mini‐screw insertion
Authors: Baumgaertel Sebastian , Hans Mark G.
Published: March 2009

Objective: To investigate the bone depth at the infrazygomatic crest with regard to orthodontic mini‐screw insertion.

Material and methods: Twenty‐nine adult human dry skulls were imaged using CBCT technology, slice data were generated and multiple measurements were undertaken at three sites associated with the infrazygomatic crest and five different measurement levels. The data were analyzed using intraclass correlation and repeated measures ANOVA.

Results: The greatest bone depth was available at, on average, 11.48±1.92 mm apical from the cemento‐enamel junction of the maxillary first molar and decreased rapidly further apically. Maximum bone depth (7.05±3.7 mm) was present at the lowest measurement level. However, here, insufficient clearance to the molar roots was present. Both the measurement site and the level at which the measurements were conducted had a significant impact on bone depth.

Conclusions: When inserting orthodontic mini‐screws (6 mm or longer) into the infrazygomatic crest while staying clear of the molar roots perforation of the maxillary sinus or the nasal cavity can be expected, but bone depth varies considerably between individuals.
Two cutaneous malignant melanomas at the same anatomic site: a case report with molecular evaluation
Authors: Edinger James T. , Radfar Arash , Jukic Drazen M.
Published: March 2009

Patients who have had malignant melanoma are at an increased risk of developing a second primary melanoma compared with the general population risk of developing a first melanoma. Many of these second primary melanomas occur at a similar anatomic site as the first lesion. Determining whether a second lesion is indeed a separate primary vs. a metastasis or locoregional recurrence can be very difficult histologically. We report the case of a patient who developed a second melanoma, 2 years after the initial diagnosis, within 3 cm of the site of the original lesion. Because of distinct histomorphologic features, the second lesion was favored to be a separate primary. However, because of the nearly identical anatomic location, molecular testing for loss of heterozygosity and BRAF mutation was performed to help further make this distinction. The first lesion was found to have loss of heterozygosity and a BRAF mutation that were not present in the second lesion. While these tests cannot elucidate the true molecular origin of these lesions, they provide a useful clinical tool to assess whether a second lesion should be treated as a recurrence or as a separate lesion with unique biologic potential.
Experimental hyperhomocysteinaemia: differences in tissue metabolites between homocystine and methionine feeding in a rat model
Authors: Pexa A. , Herrmann M. , Taban‐Shomal O. , Henle T. , Deussen A.
Published: February 2009

Aim:  Hyperhomocysteinaemia, diagnosed by serum levels, is regarded as an independent risk indicator for cardiovascular events and is associated with various diseases. The pathomechanisms seem to be partly due to concentrations of homocysteine metabolites and their effect on the cellular transmethylation processes.

Methods:  We compared two common models for experimental hyperhomocysteinaemia – high methionine diet and homocystine‐enriched diet – regarding their effects on tissue concentrations of homocysteine metabolites.

Results:  Both diets induced hyperhomocysteinaemia without affecting renal function or vitamine status. However, the tissue contents of homocysteine and its precursors S‐adenosyl‐homocysteine (SAH) and S‐adenosyl‐methionine exhibited major differences between both models. Transmethylation potential was elevated 1.7‐fold in liver of rats fed the methionine diet, whereas it was unaltered after homocystine‐enriched diet. Kidneys of rats fed the methionine diet did not show any alterations in tissue content of homocysteine and its precursors, whereas in the homocystine group homocysteine and the transmethylation inhibitor SAH were elevated from 23.1 ± 10.4 to 78.0 ± 26.0 nmol g−1 and from 106 ± 4 to 170 ± 22 nmol g−1 respectively. Homocysteine tissue content was elevated in the homocystine, but not in the methionine group.

Conclusions:  Alterations to homocysteine metabolism are distinct in both models. These findings may explain divergent results, which have been published for these models of hyperhomocysteinaemia and which have resulted in controversial discussions in the past.
Circulatory effects of apnoea in elite breath‐hold divers
Authors: Joulia F. , Lemaitre F. , Fontanari P. , Mille M. L. , Barthelemy P.
Published: February 2009

Aim:  Voluntary apnoea induces several physiological adaptations, including bradycardia, arterial hypertension and redistribution of regional blood flows. Elite breath‐hold divers (BHDs) are able to maintain very long apnoea, inducing severe hypoxaemia without brain injury or black‐out. It has thus been hypothesized that they develop protection mechanisms against hypoxia, as well as a decrease in overall oxygen uptake.

Methods:  To test this hypothesis, the apnoea response was studied in BHDs and non‐divers (NDs) during static and dynamic apnoeas (SA, DA). Heart rate, arterial oxygen saturation (SaO2), and popliteal artery blood flow were recorded to investigate the oxygen‐conserving effect of apnoea response, and the internal carotid artery blood flow was used to examine the mechanisms of cerebral protection.

Results:  The bradycardia and peripheral vasoconstriction were accentuated in BHDs compared with NDs (P < 0.01), in association with a smaller SaO2 decrease (−2.7% vs. −4.9% during SA, P < 0.01 and −6% vs. −11.3% during DA, P < 0.01). Greater increase in carotid artery blood flow was also measured during apnoea in BHDs than in controls.

Conclusion:  These results confirm that elite divers present a potentiation of the well‐known apnoea response in both SA and DA conditions. This response is associated with higher brain perfusion which may partly explain the high levels of world apnoea records.
Ageing influences myonuclear domain size differently in fast and slow skeletal muscle of rats
Authors: Brooks N. E. , Schuenke M. D. , Hikida R. S.
Published: February 2009

Aim:  In multinucleated skeletal muscle, a myonuclear domain is the region of cytoplasm governed by one nucleus, and myofibres are mosaics of overlapping myonuclear domains. Association of ageing and myonuclear domain is important in the understanding of sarcopenia and with prevention or combating age‐related muscle declines. This study examined the effects of age, fibre type and muscle on nucleo‐cytoplasmic (N/C) relationships as reflecting myonuclear domain size.

Methods:  The N/C was compared in fibre types of soleus and plantaris muscles from young (n = 6) and ageing (n = 8) male Fisher 344 rats.

Results:  There were no significant differences in fibre type composition or cross‐sectional area of the soleus across ages. The old soleus had significantly more myonuclei, resulting in a significantly smaller myonuclear domain size. The plantaris muscle showed a higher percentage of slow fibres in old compared with young fibres. There were no differences in the number of myonuclei or in myonuclear domain size between young and older animals.

Conclusion:  We found muscle‐specific differences in the effects of ageing on myonuclear domain, possibly as a result of reduced efficiency of the myonuclei in the slow muscles.
Warrior‐Monks in Japanese History1
Authors: Adolphson Mikael S.
Published: March 2009

Japan's early medieval age, roughly the late eleventh through the late fourteenth centuries, is usually described as an age when power shifted from noble elites to the warrior class, most commonly embodied in the cultic samurai. However, scholars subscribing to the notion of a clearly defined military class with a common ethos from this period will find few figures in the premodern age that correspond to those idealized images. Those who fought came from all facets of society, indicating that the separation of the samurai from other warriors was a much later invention. This distinction of different fighters have affected monastic warriors more than any other group, for they have been seen as a negative influence on society, often referred to by the later term sōhei (monk‐warriors). This essay explores the social origins of monastic warriors, their relationship to those we now call samurai (or bushi) during the early medieval age, and the later creation of stereotypical images of evil naginata (glaive)‐wielding monks that have dominated both popular culture and academe until the present.
Using Intersectionality to Examine the New Complexities of Work Identities and Social Class
Authors: Kirk John
Published: March 2009

This article explores how the concept of intersectionality is useful for examining how class location and gender intersect in the workplace. Intersectionality foregrounds the complex ways that work identity is negotiated and achieved and how formations of identity constitute complex affiliations, solidarities and tensions in the workplace. I use data from oral histories of railway workers to illustrate the usefulness of intersectionality as an approach to analysing work. Intersectionality and the concept of structures of feeling are important tools for examining how work shapes social identity and action. These concepts have been central to an important research project conducted at the Working Lives Research Institute, part of the wider ESRC Identities programme.
Effect of transmurally heterogeneous myocyte excitation–contraction coupling on canine left ventricular electromechanics
Authors: Campbell Stuart G. , Howard Elliot , Aguado‐Sierra Jazmin , Coppola Benjamin A. , Omens Jeffrey H. , Mulligan Lawrence J. , McCulloch Andrew D. , Kerckhoffs Roy C. P.
Published: February 2009

The excitation–contraction coupling properties of cardiac myocytes isolated from different regions of the mammalian left ventricular wall have been shown to vary considerably, with uncertain effects on ventricular function. We embedded a cell‐level excitation–contraction coupling model with region‐dependent parameters within a simple finite element model of left ventricular geometry to study effects of electromechanical heterogeneity on local myocardial mechanics and global haemodynamics. This model was compared with one in which heterogeneous myocyte parameters were assigned randomly throughout the mesh while preserving the total amount of each cell subtype. The two models displayed nearly identical transmural patterns of fibre and cross‐fibre strains at end‐systole, but showed clear differences in fibre strains at earlier points during systole. Haemodynamic function, including peak left ventricular pressure, maximal rate of left ventricular pressure development and stroke volume, were essentially identical in the two models. These results suggest that in the intact ventricle heterogeneously distributed myocyte subtypes primarily impact local deformation of the myocardium, and that these effects are greatest during early systole.
Hormones as epigenetic signals in developmental programming
Authors: Fowden Abigail L. , Forhead Alison J.
Published: February 2009

In mammals, including man, epidemiological and experimental studies have shown that a range of environmental factors acting during critical periods of early development can alter adult phenotype. Hormones have an important role in these epigenetic modifications and can signal the type, severity and duration of the environmental cue to the developing feto‐placental tissues. They affect development of these tissues both directly and indirectly by changes in placental phenotype. They act to alter gene expression, hence the protein abundance in a wide range of different tissues, which has functional consequences for many physiological systems both before and after birth. By producing an epigenome specific to the prevailing conditionin utero, hormones act as epigenetic signals in developmental programming, with important implications for adult health and disease. This review examines the role of hormones as epigenetic signals by considering their responses to environmental cues, their effects on phenotypical development and the molecular mechanisms by which they programme feto‐placental development, with particular emphasis on the glucocorticoids.
Examining Interfacial Diffuse Phonon Scattering Through Transient Thermoreflectance Measurements of Thermal Boundary Conductance
Authors: Norris Pamela M. , Hopkins Patrick E.
Published: March 2009

Today’s electronic and optoelectronic devices are plagued by heat transfer issues. As device dimensions shrink and operating frequencies increase, ever-increasing amounts of thermal energy are being generated in smaller and smaller volumes. As devices shrink to length scales on the order of carrier mean free paths, thermal transport is no longer dictated by the thermal properties of the materials comprising the devices, but rather the transport of energy across the interfaces between adjacent materials in the devices. In this paper, current theories and experiments concerning phonon scattering processes driving thermal boundary conductance (hBD) are reviewed. Experimental studies of thermal boundary conductance conducted with the transient thermoreflectance technique challenging specific assumptions about phonon scattering during thermal boundary conductance are presented. To examine the effects of atomic mixing at the interface on hBD, a series of Cr/Si samples was fabricated subject to different deposition conditions. The varying degrees of atomic mixing were measured with Auger electron spectroscopy. Phonon scattering phenomena in the presence of interfacial mixing were observed with the trends in the Cr/Si hBD. The experimental results are reviewed and a virtual crystal diffuse mismatch model is presented to add insight into the effect of interatomic mixing at the interface. The assumption that phonons can only transmit energy across the interface by scattering with a phonon of the same frequency—i.e., elastic scattering, can lead to underpredictions of hBD by almost an order of magnitude. To examine the effects of inelastic scattering on hBD, a series of metal/dielectric interfaces with a wide range of vibrational similarity is studied at temperatures above and around materials’ Debye temperatures. Inelastic scattering is observed and new models are developed to predict hBD and its relative dependency on elastic and inelastic scattering events.
Experimental Observation of Single Bubble Rise Characteristics in Various Situations
Authors: Okawa Tomio , Tanaka Tomoe , Torimoto Kazuhiro , Nishiura Masanori , Kataoka Isao
Published: March 2009

The effects of liquid temperature and injection method on single bubble rise characteristics in clean still water were experimentally investigated. It was confirmed that the shape and rise velocity of a bubble strongly depend on the method of bubble formation. For the rise velocity in high temperature water, the correlation for fully contaminated liquid might be appropriate even in the clean water. Because of the importance in the numerical simulation of bubbly two-phase flow, the experimental information on rise path oscillation such as amplitude and frequency was also reported.
Computational Study of the Flow Around a Ducted Tip Hydrofoil
Authors: Ingvarsdottir Hildur , Ollivier-Gooch Carl , Green Sheldon I.
Published: March 2009

Steady flow over rounded and ducted tip hydrofoils has been studied computationally using the CFDRC-ACE(U) flow solver and a k-ε turbulence model. The flow domains were gridded with a combination of C-H, H-H, tetrahedral and prism grid blocks and mesh sizes ranged from 350,000–550,000 cells. A good agreement in flow pattern was achieved between the numerical solutions and available experimental data. The computations show that the ducted tip hydrofoil sheds less bound circulation over the majority of the wing span than does a rounded tip hydrofoil with the same cross section and aspect ratio. Observation of the streamwise component of vorticity immediately downstream of the different hydrofoils shows that the vorticity from the ducted tip hydrofoil is shed in the shape of a duct instead of the concentrated circular vortex shed by the rounded tip hydrofoil.
Large Eddy Simulation of the Wake Behind a Turning Ship
Authors: Yavuz Ibrahim , Cehreli Zeynep N. , Celik Ismail B. , Shi Shaoping
Published: March 2009

This study examines the dynamics of turbulent flow in the wake of a turning ship using the large eddy simulation (LES) technique. LES is applied in conjunction with a random flow generation (RFG) technique originally developed at West Virginia University to provide unsteady inflow boundary conditions. As the ship is turning, the effects of the Coriolis and centrifugal forces on vortical structures are included. The effects of the Coriolis force on the flow-field are assessed and a grid sensitivity study is performed. The predicted turbulence structures are analyzed and compared with the wake of a non-turning ship.
Fundamental Energy Transfer Mechanism of Turbomachinery
Authors: Tanaka Takaharu
Published: March 2009

Fundamental mechanisms of energy transfer, which is caused between impeller blade and fluid particles in centrifugal pumps and water turbines, are discussed together with as a turbomachinery under same theoretical basement. This leads to the result that the fluid flow which directs radial outward in pump and that radial inward in water turbine are neither caused by centrifugal force nor centripetal force, but caused by tangential forward force, which acts on the impeller blade in the direction perpendicular to rotational radius. Hydraulic energies of fluid particles transferred from mechanical to hydraulic energy in pump and that to be transferred from hydraulic to mechanical energy in water turbine appear as centrifugal force FHCF in rotational flow passage.
Direct Numerical Simulation of the Manufacturing of a Coating on a Substrate by Projection
Authors: Le Bot Ce´dric , Arquis Eric
Published: March 2009

The purpose of this paper is to simulate numerically the impact of droplets onto a substrate to give a better knowledge of coating manufacturing. A 2D model is proposed, with symmetry conditions to simulate the impact of an infinity of identical droplets. The dynamic behavior is studied, and a thermal study of superimposed splats is added separately to give a better understanding of each phenomenon.
Integrated Diagnostic System for the Equipment of Power Plants: Part II — The Expert System
Authors: Kubiak S. J. , Urquiza B. G. , Garci´a-Gutierrez A.
Published: March 2009

This paper describes the development of an Expert System for identification of generating equipment faults caused by wearing out of their components, which decrease the efficiency and thus the heat rate of a generating plant. In a sister paper [1], the formulation was presented and the algorithms for the principal equipment were developed. The Expert Systems are based on the above algorithms. Also, in some case a vibration analysis is used jointly with thermodynamic analysis to locate precisely a fault, for example in a case of rubbing which damaged the seals of the turbine and/or compressors. The system is used off-line, however it can be installed on-line with a monitoring system. The Expert Systems identify the faults of the gas turbine, the compressor and the steam turbine. Auxiliary equipment faults are presented in the form of tables also, listing the symptoms and their causes [1]. The knowledge levels and the separate bases are built into the systems.
A Computational Workbench Environment for Virtual Simulation of a Vision 21 Energyplex
Authors: Bockelie Michael J. , Swensen David A. , Dension Martin K. , Chen Zumao , Senior Constance L. , Sarofim Adel F.
Published: March 2009

In this paper we describe our progress toward creating a process workbench for performing virtual simulations of DOE Vision 21 energyplex systems. The workbench provides a framework for incorporating a full complement of models, ranging from simple heat/mass balance reactor models that run in minutes to detailed models that can require several hours to execute. Provided herein is an overview of a process workbench for a conventional PC power plant developed during the past year and our current efforts at developing a workbench for a gasifier based energyplex configuration.
Fogging for Evaporative Cooling Effects on Siemens V94.2 Gas Turbine Performance
Authors: Brusca S. , Lanzafame R.
Published: March 2009

In order to study the effects of ambient temperature and relative humidity on the performance of the Siemens V94.2 gas turbine, installed as a topper in an IGCC complex and fed with syngas, a mathematical model of the engine has been developed and implemented into GateCycle environment. The model was fine tuned using experimental data of plant. Thermodynamic analysis of the gas turbine performance, depending on ambient temperature and relative humidity, has been carried out. Results show the strong dependence of engine performance on ambient temperature (in the range from 30 °C to 40 °C). Theoretical and experimental results have been shown that ambient air humidity decreases power losses due to high external temperature. In order to optimize power production in this temperature range, an artificial humidifier was implemented into the model. Furthermore, “Fogging for Evaporative Cooling” technique effects on performance of the gas turbine have been studied. Using GateCycle model, simulations have been carried out as regards to temperature variation in the range which power losses occur. Two control strategies of the artificial air humidifier have been implemented: the first is characterized by an air humidity constant at the intake of the compressor (set to 95%); the second one is characterized by an air temperature constant at the intake of the compressor (set to the temperature corresponding to maximum IGV opening). For both control strategies, power losses recovery can be achieved depending on base air humidity and temperature. Applying the second control strategy, lower water consumption was achieved but a compression ratio very close to the limit value was observed.
Case History of Repairing Cracking in the Seam Welds of 1950 Vintage Pipe Using the Steel Compression Reinforcement Technology
Authors: Smyth Robert J. , Spitzmacher Derek K.
Published: March 2009

Platte Pipeline operates a 1500 km NPS 20” (508 mm) crude oil pipeline connecting Casper, Wyoming to Wood River, Illinois USA. The pipeline was constructed in the early 1950’s with low frequency electric resistance welded (ERW) and flash welded (FW) pipe. The Steel Compression Reinforcement Technology (PetroSleeve) was used to repair active ERW and FW seam cracking detected by an in-line inspection tool. All repairs were performed while the pipeline was in operation. Prior to undertaking the field rehabilitation program, engineering analysis and severe testing was performed to confirm that the steel compression reinforcement technology would arrest fatigue crack extension. Two significant defects were manufactured in the long seam of separate sections of 1950’s vintage line pipe that had been removed from service. The defects included a 50% through-wall manufactured crack and a 70% through-wall electrically discharged machined semi-elliptical slot anomaly. Compression sleeves were installed over both defects, and cycled 36,500 times with internal pressures ranging from 700 kPa to 8000 kPa. Following the cyclic pressuring, the crack and corrosion anomalies were metallurgically inspected. No crack extension or crack development was observed nor detected. At the conclusion of the engineering testing and analysis, it was accepted that the technology permanently restored the serviceability of the pipe by reducing stress levels and preventing crack growth. Platte Pipeline saved significant dollars by using this technology. The time and expenses associated with nitrogen purges and pipe cutouts were avoided. Also, Platte was able to maintain crude oil deliveries at near normal levels throughout the repair program. This paper reviews the engineering analysis, cyclic testing, and field installation practices associated with the Platte rehabilitation program.
Pipeline Management With Photogrammetry, Laser Scanning and WEB Mapping
Authors: de Albuquerque Vasconcelos Elinaldo , Brandalize Amauri Alfredo , Amado Ulisses Dias
Published: March 2009

The up-to-date and true information is one of the most important items of a business, mainly when this business acts in international markets due to the participation of international Companies. TRANSPETRO, integral subsidiary of PETROBRAS, is the Brazilian operator for the great majority of pipelines of petroleum and natural gas in Brazil, built among the years of 1951 and 2001. Fifty years of pipeline history are registered in the most different formats and media ways. This situation generated difficulties to access the information and consequently it provoked the occurrence of lacks of information. The most serious problems were observed in the moment of retrieving the information about the location of the old pipelines when the implantations of new ones are required or in the case of an emergency intervention. Investments of US$ 15 million (2001/2002) were accomplished by mapping (orthophotos), detailed drawings with as-built status and profiles, installed equipment (valves etc), geodesic network with high precision points with GPS coordinates (Global Positioning System), new register of land-owners of the right-of-way, users and operators training, data distribution in the Company network (Intranet) in GIS format — Geographical Information System, formed an alliance with the WEB Mapping. For the execution of the activities several technologies were used, including airborne sensors (laser scanning and aerial photos). Now, a database with high degree of precision can be accessed by the users with images of high definition, to verify information of the installed equipment and to do the planning of amplifications of the system or maintenance, resulting in larger operational reliability of the pipelines.
Horizontal Directional Drilling as a Solution for Crossing of Ridges in the Serrana Province, Mato Grosso, Brazil
Authors: Pellerin Denis , Dura˜o Alaide M. , Jardim Jose´ E. F. P. , Pimenta Carlos , Miura Kazumi
Published: March 2009

The crossing of a series of high, parallel, elongated and with steep scarp mountains in the Serrana Province, between Ca´ceres and Cuiaba´, Mato Grosso State, Brazil, constituted a great technical challenge for implementation of the Bolivia - Mato Grosso gas pipeline. Due to environmental preservation, the gas pipeline could not cross the crest of some of these mountains using conventional surface methods and the alternative of surrounding the mountains would have caused an extended additional path, with appreciable additional cost. The economically viable alternative was the horizontal directional drilling through the most critical mountains: Piraputanga Ridge with 850m, Cachoeirinha Ridge with 943m and Palmeiras Ridge with 867m. One of the difficulties was the drilling of the very compact and abrasive Alto Paraguay Group Proterozoic low metamorphic rocks intercalated with clastic sedimentary rocks. The horizontal directional hole intersects in high angles the strongly dipping layers of rocks. The layered sequences of sandstone capped by siltstones provide the aquifer condition to Raizama Fm. with strong water flow. To prevent any environmental damage, the conventional hole design was modified, which allowed the drilling with water, instead of bentonitic drilling fluid. The horizontal directional drilling consisted of a pilot hole with 10.14 inches diameter, drilled with down hole motor and an electromagnetic steering system. The first enlargement of the pilot hole went to 22” diameter and the last one to 30” using special reamer tools. The pipes of the Bolivia - Mato Grosso gas pipeline have 18” diameter, with a special line coating to prevent damages during pulling in contact with rocks. No problems occurred during the pulling operation of the pipes along the holes. The proposed three horizontal directional holes were very successful and the projected designs of the well were fully achieved, with a very small offset in the forecasted exit points. After long weeks of hole opening and preparatory works, all three pulling operations of the pipestrings along the holes went very smoothly.
Protected Areas and Pipelines in Canada: Balancing Natural Values With Development at the Landscape Level — The Conservation First Principle
Authors: Ewins Peter J.
Published: March 2009

“Sustainable Development” is now a widely accepted concept, yet there are surprisingly few concrete examples of it in practice. The pipeline industry operates at broad landscape and regional levels, and now has the opportunity to provide a strong lead in showcasing how society can benefit from major new energy pipelines while not significantly compromising natural and cultural values. To achieve this requires adoption of a fundamental proactive, ecosystem-based principle — the “Conservation First Principle”. In Canada this principle, first stated by Hummel [1], is that “there should be no new or expanded large-scale industrial development until a network of protected areas is reserved which adequately represents the natural region(s) affected by that development”. This approach is not new (e.g., the 1992 commitment by all levels of Canada’s governments to complete such protected areas networks), but it is more urgently needed now in an energy-rich frontier nation like Canada to truly safeguard our natural and cultural values while developing new energy corridors. It is a precautionary approach, akin to an insurance policy we would all be familiar with at a personal level. By identifying key natural habitats in each natural region (areas of similar bio-physical characteristics — there are 486 terrestrial natural regions in Canada), and using sophisticated GIS-based gap analysis, working with local communities, industry and governments, a network of protected areas can be identified and then reserved for legal protection. This network then adequately protects a representative sample of habitats, biodiversity and ecosystem processes in each natural region before or simultaneous with development proposals and approvals. The development of natural gas reserves in the Mackenzie Valley provides all stakeholders with a timely high-profile opportunity to showcase this balanced approach. The NWT’s Protected Areas Strategy provides the widely-supported community-led process to identify and then reserve key cultural and ecological areas in tandem with gas pipeline development. Investors, industry, governments, local communities and the general public all seek the greater certainty and security that such advance planning and balancing provides. The knowledge that certain key areas are off-limits to future development, and that other areas (the largest portion of each natural region) are assigned for sensitive industrial development, sets the stage for a more secure, stable future, in which all values are accommodated satisfactorily. In the push for greater energy security, the pipeline and oil and gas industry should now embrace the Conservation First Principle in energy developments across Canada’s lands and oceans, most immediately as it plans for a major gas pipeline in the Mackenzie Valley.
An Innovative Approach for Pipeline Repairs
Authors: Robertson Don , Russell Wayne , Alvares Nigel , Carrobourg Debra , King Graeme
Published: March 2009

A strategic combination of integrity software, relational databases, GIS, and GPS technologies reduced costs and increased quality of a comprehensive pipeline integrity assessment and repair program that Greenpipe Industries Ltd. completed recently on three crude oil pipelines—two 6-inch and one 8-inch—for Enbridge Pipelines (Saskatchewan) Inc. Greenpipe analyzed metal loss data from recent in-line inspection logs, calculated real-world coordinates of defects and reference welds, prioritized anomalies for repair taking environmental risks into account, and prepared detailed dig sheets and site maps using PipeCraft™, Greenpipe’s advanced GIS-based pipeline integrity-maintenance software package. GPS technology was used to navigate to dig sites and the accuracy of the GPS approach was compared with traditional chainage methods. Pipelines were purged and all defects were cut out and replaced by new pipe during a two-day shutdown on each pipeline. A comprehensive set of data, including high-accuracy GPS location of anomalies, reference welds, and replacement pipe welds, was collected at each dig site and entered into the PipeCraft relational database. After all repairs were completed, the client was provided with a GIS-based electronic final report, allowing point-and-click access to all data collected in the field, including in-line inspection logs, dig information sheets and as-built drawings. The new methodologies employed on this project resulted in a high quality, comprehensive and cost-effective integrity maintenance program.
New Approach to Pipeline Condition Monitoring of the Beatrice 16” Oil Export Line
Authors: Short Gordon , Flett Dave
Published: March 2009

The ability to detect corrosion within oil and gas pipelines has long been the preserve of the Intelligent or Smart Pig. These tools have evolved over the past 30 years into very sophisticated, but often expensive inspection options. Since 1994 RST Projects Limited, a Scottish based pipeline inspection company, has been pioneering the development of passive inspection tools that can be retrofitted to standard Cleaning or Utility Pigs. These tools are fundamentally different to traditional inspection pigs. Passive instruments (instruments which do not contain an active source or emitor, such as ultrasonic or magnetic flux leakage sensors), fitted to a Utility Pig are used to monitor its passage through a pipeline. Changes in the behaviour of the Utility Pig measured by these instruments have been demonstrated to reflect the condition of the pipeline. To date more than 40 projects, involving surveying some 4,000 km+ of operational pipelines have been completed. This paper presents the results of work undertaken to develop the first stages of a basic corrosion detection capability of the Smart Utility Pig tool. It does so by presenting findings from surveys of the 16” Beatrice Oil Export Pipeline, operated by Talisman Energy UK Limited. It also draws upon surveys carried out in other assets operated by Talisman in the UK. It explores how this technology when combined with other inspection methods offers the potential for a more integrated approach to routine pipeline condition monitoring.
Deformation Analysis of a Pipeline River Crossing
Authors: Isherwood Andy , Samcheck Alan , Savigny Wayne
Published: March 2009

In Manitoba, the Main (100) Line operated by TransCanada PipeLines Ltd. (TCPL) comprises six natural gas pipelines ranging from 864 mm to 1219 mm in diameter. These pipelines cross the La Salle River at Main Line Valve (MLV) 39+6.06, approximately 3 km south of St. Norbert, Manitoba. A rupture in Line 100-2 occurred at this crossing site on April 15, 1996. Investigations of the site following the line break concluded that ground movement associated with the east approach slope was likely a contributing factor in the failure of Line 100-2. It was postulated that the observed slope instability was attributable, at least in part, to a combination of the low shear strength of Lake Agassiz clay and artesian pore pressures associated with the underlying regional Upper Carbonate Aquifer (UCA), controlled in part by groundwater pumping within the City of Winnipeg. Based on the findings from the initial slope stability analyses, a more detailed deformation analysis was proposed to examine the influence of hydrogeological conditions on deformation and slope stability at the La Salle site. The numerical analyses were conducted using FLAC2D, a two-dimensional explicit finite difference code for engineering mechanics computation. The code simulates the pre- and post-peak behaviour of geological and other materials based on specified material properties, constitutive models, and failure criteria. The deformation analysis has identified the key factors controlling stability of the east approach slope at the La Salle site, and has provided insight into probable failure mechanisms. High pressures in the UCA increase the risk of sudden large-scale slope failure at the slope toe at critical times during the year, e.g., after rapid drawdown following the spring flood, and following the drop in river level in late fall to winter levels. The analysis indicated that the risk of slope instability at this site can be reduced by lowering the aquifer pressure locally in the vicinity of the east approach slope at critical times in the year. The results of the study have demonstrated the usefulness of employing deformation analysis as a means of understanding the key factors controlling slope stability at a particular site. The approach is also compatible with the development of a comprehensive soil/pipe interaction methodology that integrates the results of ongoing in situ monitoring into pipe stress analyses.
Satellite-Based Monitoring of Slope Movements on TransCanada’s Pipeline System
Authors: O’Neil Gregg , Samchek Alan
Published: March 2009

TransCanada owns and operates over 38,000 km of pipeline throughout North America, which cross over 3,300 slopes and 1,200 watercourses. Ground movements on slopes at river crossings are an important pipeline hazard across Canada and especially within the Alberta system. These movements have led to several past pipeline ruptures and the development of a relatively extensive slope monitoring program. Historically, ground movement impacts are an industry-wide problem. The results of a 1998 study by the Gas Research Institute reported that external force damage from natural forces, including ground movement, was responsible for approximately 12 percent of all incidents reported on U.S. onshore pipelines between 1985 and 1994. Of all natural force incidents, ground movement accounted for approximately 29 percent of the total, on average. Furthermore, of all fires or explosions resulting from pipeline incidents, ground movements were reported responsible for about 5 percent of the total. In a similar study of Alberta pipeline failures and incidents between 1980 and 1997 (EUB, 1998), ground movement was the cause of 56 ruptures, or 3.5 percent of the total. Until recently, monitoring of the progress of slope movements was reactive and undertaken in a traditional fashion, using primarily slope inclinometers and/or ground surveys. Recently, however, TransCanada has adopted a proactive approach for the management of ground movements. Consistent with the management of other pipeline hazards, such as corrosion, ground movements are cast in a risk-based framework. The application of DInSAR technology, Differential Interferometry applied to satellite synthetic aperture radar (SAR) imagery, fits well within the proactive approach and has proven successful in measuring ground movements on ROW slopes to sub-centimetre accuracy. In 2000, a Pipeline Research Committee International (PRCI) study was carried out on a TransCanada Right of Way (RoW) that compared conventional slope indicator readings with DInSAR technology and proved the capability of the technology. TransCanada has begun to use DInSAR technology in this program of monitoring Alberta slopes. Typically, TransCanada monitors slope movements at 53 sites with frequency of readings between bi-annually and 4 times per year using conventional methods. Since 2001, 14 slopes on the TransCanada system have been instrumented using DInSAR methods and monitoring of movements using interferometric methods is continuing.
Riser Fatigue Due to Currents and Waves
Authors: Le Cunff C. , Fontaine E. , Biolley F.
Published: March 2009

Fatigue due to environmental conditions is studied on a top-tensioned riser. The fatigue is due to two factors. First, the waves produce a displacement of the top of the riser, which excites the structure. Secondly, currents create vortices behind the structures. The phenomenon is then referred to as vortex-induced vibrations (VIV), whereby the vortices can lock onto a structural mode through the shedding frequency. In the present paper, we have two objectives. The first is to compare the fatigue estimates given either by a modal analysis or by Navier-Stokes calculations for a riser in a current. The second is to determine if studying the wave and current effects separately produces conservative results or if they must be studied together.
Flexible Riser Fatigue Procedure Using a Long Term Distribution of FPSO’s Heading Direction
Authors: Duarte de Lemos Carlos Alberto , Vaz Murilo Augusto
Published: March 2009

The intensive use of FPSOs in Campos Basin, offshore Brazil, has demanded more attention on the fatigue design of flexible risers. Field experience and a new set of environmental data collected in the last years have shown a large number of swell waves reaching the floating units in quartering and beam seas, which has amplified the motions at the risers’ top connections. Hence, it is necessary to evaluate the occurrence probability of wave heading direction relative to the vessel, especially for beam seas, but also noting the probability increase of quartering seas considering the existence of bi-modal and bi-directional wave spectra. The simultaneous environmental conditions — wind, current and bi-directional waves (sea and swell) — registered in Campos Basin, were condensed in a few hundreds environmental conditions to enable its utilization on a simulation program, where the FPSO, mooring lines and risers were modeled to obtain the mean heading and offsets. This new set of FPSO headings were then used to define a new proposal of load conditions to evaluate the fatigue life of flexible risers. This new procedure was then applied to a case study for the FPSO P-33 employing the tools available at PETROBRAS research center. The results have confirmed the importance of beam and quarter seas, which respectively cause heavy roll and vertical motions at the turret and then, affecting the fatigue of the risers.
Technical Solutions Applied for the Treatment of Damaged Dynamic Risers
Authors: Taylor Thomas S. , Joosten Michael V. , Smith Frank
Published: March 2009

The objective of this paper is to provide operators of floating production systems that utilise dynamic flexible risers an opportunity to review the technology and procedures adopted by PGS Production. These procedures were utilised in order to verify/re-use the damaged/seawater annulus flooded Banff risers. Most of these risers were also classified as being safety critical. The scope of the work carried out covers the development of a seawater displacement treatment system using an inhibitor fluid. The feasibility and efficacy of the flushing treatment were rigorously developed based on hydraulic test analysis using sections taken from an actual flexible riser. An extensive corrosion fatigue-testing programme using seawater/CO2/inhibitor was carried out to establish optimal safe service lives for the “damaged and treated” case for these risers. This paper presents the successful results from this work covering the development of the remedial treatment process and the resulting corrosion fatigue work that has been conducted.