bluuebunny/crossref_metadata_2025_split huggingface dataset:
Probable Interaction Between Warfarin and Marijuana Smoking
Authors: Yamreudeewong Weeranuj , Wong Hing Ka , Brausch Laura M , Pulley Keri R 
Published: June 2009

Objective:To report a probable interaction between warfarin and marijuana smoking, resulting in increased international normalized ratio (INR) values and bleeding complications.Case Summary:A 56-year-old white male had been receiving chronic warfarin therapy for 11 years after mechanical heart valve replacement. He was admitted to the hospital with a diagnosis of upper gastrointestinal bleeding. Upon admission, his INR value was supratherapeutic at 10.41, and his hemoglobin level was 6.6 g/dL He received 4 units of fresh frozen plasma and one 10-mg dose of oral vitamin K; his INR was 1.8 the next day. He was discharged 7 days after admission. Fifteen days after hospital discharge, he was readmitted with a constant nosebleed and increased bruising. His INR value was 11.55. After treatment, he was discharged with an INR value of 1.14. The patient smoked marijuana more frequently throughout the period of these 2 hospitalizations due to his depression. He was counseled by the pharmacist on the potential interaction of warfarin and marijuana. The patient decided to stop smoking marijuana after the third counseling session. During the 9 months that he did not smoke marijuana, his INR values ranged from 1.08 to 4.40 with no significant bleeding complications.Discussion:Marijuana may increase warfarin anticoagulant effect by inhibiting its metabolism, and to a lesser extent, displacing warfarin from protein-binding sites. Other causes (eg, nonadherence) of the patient's increased INR were ruled out. Using the Horn Drug Interaction Probability Scale, our patient's warfarin–marijuana interaction appeared to be probable.Conclusions:To our knowledge, there have been no other reported cases of warfarin–marijuana interaction. While more clinical reports would be useful to confirm this interaction, clinicians should be aware of its probability so as to manage patients appropriately.
The film-opera Aida (1953): intermediality and operatics
Authors: Kuhn Bernhard 
Published: June 2009

This article offers an intermedial analysis of the film-operaAida(dir. Clemente Fracassi, 1953) within the context of opera adaptation in Italian cinema. Drawing on theories of intermediality developed by Wolf and Rajewsky, it adopts and applies the intermedial subcategories of medial transposition, plurimediality and intermedial reference to the study of film-operas. By comparing the filmAidawith the libretto and the score of Verdi's opera, the article first considers the medial transpositions of the text as well as the music. In a second layer of analysis, it examines plurimediality and intermedial references in the film-opera in order to evaluate the integration of operatic elements into the film.The article concludes that the film-operaAidarepresents a hybrid work of art situated between opera and cinema. Instead of attempting to record the opera in a naturalistic way, Fracassi presents an opera with filmic means, also by simulating and partially recreating operatic characteristics within the film's discourse. By demonstrating thatAidaindeed offers a creative and cinematographically innovative adaptation of the opera's libretto and score, the article not only re-evaluates this film-opera, but additionally highlights the usefulness of the intermedial approach for the analysis of opera adaptations.
Maternal serum adiponectin multimers in gestational diabetes
Authors: Mazaki-Tovi Shali , Romero Roberto , Vaisbuch Edi , Erez Offer , Mittal Pooja , Chaiworapongsa Tinnakorn , Kim Sun Kwon , Pacora Percy , Yeo Lami , Gotsch Francesca , Dong Zhong , Yoon Bo Hyun , Hassan Sonia S. , Kusanovic Juan Pedro 
Published: June 2009

Abstract

Objective: Adiponectin, an adipokine with profound insulin-sensitizing effect, consists of heterogeneous species of multimers. These oligomeric complexes circulate as low-molecular-weight (LMW) trimers, medium-molecular-weight (MMW) hexamers and high-molecular-weight (HMW) isoforms and can exert differential biological effects. The aims of this study were to determine whether there is a change in circulating adiponectin multimers in the presence of gestational diabetes mellitus (GDM), overweight/obesity or with a treatment with sulfonylurea or insulin in patients with GDM.

Study design: This cross-sectional study included women with: 1) normal pregnancy (n=149); and 2) patients with GDM (n=72). Thirty-three patients with GDM were managed with diet alone. Among the others 39 diabetic patients, 17 were treated with Glyburide and 22 with insulin. The study population was further stratified by first trimester body mass index (BMI) (normal weight <25 kg/m2 vs. overweight/obese ≥25 kg/m2). Serum adiponectin multimers (total, HMW, MMW and LMW) concentrations were determined by ELISA.

Results: 1) The median maternal serum of total, HMW, MMW and LMW were lower in patients with GDM than in those with normal pregnancies (P<0.001 for all comparisons); 2) patients with GDM had a lower HMW/total adiponectin ratio and a higher MMW/total and LMW/total adiponectin ratio than those with a normal pregnancy (P<0.001 for all comparisons); and 3) among GDM patients, there were no differences in the concentrations and relative distribution of adiponectin multimers between those who were managed with diet, and those who were treated with pharmacological agents.

Conclusion: 1) GDM is characterized by a distinctive pattern of concentrations and relative distribution of adiponectin multimers akin to Type 2 diabetes mellitus; 2) dysregulation of adiponectin multimeres can provide a mechanistic basis for the association between adiposity and GDM.
Integrity Assessment of Well Barriers Threatened by Increasing Casing-Hanger Loads
Authors: Okstad Eivind H. , Sangesland Sigbjørn 
Published: June 2009

Summary
Degradations or interruptions of the original well-barrier elements might occur at offshore wells after some time in operation. Experience from the Norwegian Continental Shelf (NCS) has shown that these problems are not always treated as thoroughly as expected by the parties involved. This paper presents an approach for an efficient visualization and description of interrupted well barriers, basically to increase the well-barrier control and management. By mapping the history of operational demands and load picture of the well in combination with the status of well barriers, a consistent basis for evaluations is obtained. The main intention is thus to realize the real well problem and its underlying causes in a controlled and systematic manner. Then, the responsible parties involved can take action more accurately according to the type of failure that has been revealed.
Formation Damage Caused by Emulsions During Drilling With Emulsified Drilling Fluids
Authors: Fjelde Ingebret 
Published: June 2009

Summary
The potential for macroemulsions to cause formation damage during drilling with emulsified drilling fluids [oil-based mud (OBM)] has been studied for consolidated low-to-medium-permeability sandstone. Two types of emulsified drilling fluids were used, one with mineral-based (MB) oil and one with synthetic-based (SB) oil.
The emulsions in tested OBM were found to be stabilized both by emulsifiers and particles (organoclay and drilled solids). At low shear rates, aggregates of water droplets and particles were observed by microscopy. In bulk experiments, the stability of emulsions formed by the mixing of mud filtrates and reservoir fluids was found to depend on the compositions of emulsified drilling fluid and crude oil. These emulsions were found to cause severe formation damage in corefloods at 90°C. The damages were partly removed during aging at higher temperatures (120 and 150°C). At 90°C, the emulsions appeared to be more stable in cores than in bulk.
The potential for emulsion invasion will be highest during the spurt period, especially if the emulsions in the muds are not stable. The amount of emulsion invasion will increase with filtration pressure. Creation of emulsion in the oil reservoirs will be easiest at high shear rates (e.g., in the spurt period and in the start of the oil production) and high concentrations of emulsifiers in the mud filtrate and reservoir oil.
The risk for emulsion invasion and creation of emulsion during drilling can be reduced by avoiding high overbalanced pressure and minimizing the fluid loss. The potential for the creation of emulsions during start of production can be reduced by starting with low drawdown.
Formation damage caused by emulsions can be nonpermanent. Because emulsions are thermodynamically unstable, the potential for permanent damage caused by emulsions will usually be lower at higher temperatures (studied mud systems showed a change between 90 and 120°C). Mechanisms for stabilization and, thereby, also for breaking of emulsions depend on the compositions of the mud filtrate and the reservoir fluids. If the damaged area is swept by the produced oil, removal of emulsions by dilution with the oil can be possible.
Use of synthetic oil instead of the crude oil in laboratory experiments can give incorrect estimates of the potential for formation damage caused by emulsions. Short laboratory experiments can also give excessively high estimates of the potential for permanent emulsion-related formation damage.
Olefin-Based Synthetic-Drilling-Fluids Volumetric Behavior Under Downhole Conditions
Authors: Demirdal Barkim , Cunha Jose C. 
Published: June 2009

Summary
Usual practice in drilling engineering is to determine drilling-fluid density at surface conditions assuming that drilling-fluid density does not change with changing downhole conditions. This assumption may result in inaccuracy while estimating static and dynamic pressures in the wellbore, especially when synthetic-based drilling fluids are used. Inaccurate estimation of the pressure profile in the annulus can lead to severe well problems such as kicks, drilling-fluid losses, and wellbore instability. In addition, inaccurate pressure-profile estimation can affect the success of managed-pressure-drilling (MPD) operations, which require real-time knowledge of wellbore pressures to keep wellbore pressure between formation pore and fracture pressures using a control choke placed on the return line of the annulus.
Effects of pressure and temperature on volumetric behavior of two olefin-based synthetic oils are investigated in this study using a mercury-free pressure/volume/temperature (PVT) system. The olefin-based synthetic oils used in this study are C16C18 internal olefin (IO) and C12C14 linear alpha olefin (LAO). To simulate deep offshore situations, the temperature is ranged between 25 and 175°C, while the pressure is ranged between 0 and 14,000 psig.
In addition, volumetric performances of olefin-based synthetic-oil systems under investigation are compared with those of water, brine solution, mineral oil, diesel oil, and n-paraffin-based oil under similar conditions.
The study shows that the volumetric properties of synthetic-based oils are more sensitive to pressure and temperature conditions compared to water, brine solutions, mineral oil, and diesel oil. Once emulsion systems containing synthetic-based oils are used, density change with respect to downhole conditions should be modeled to increase the reliability of pressure-profile calculations.
Increasing Production by Maximizing Underbalance During Perforation Using Nontraditional Lightweight Completion Fluid
Authors: Jan Badrul M. , Rae Graeme R. , Noor M. Ishenny , Suhadi An N. , Devadaas Melvin 
Published: June 2009

Summary
The invasion of the pulverized formation rock grains and the resulting low-permeability crushed zone is the primary cause of wellbore damage in perforated completions, as established by Behrmann et al. (1991). To minimize this damage during the perforating process, it is necessary to provide a dynamic underbalance in the well that will deliberately induce flow into the wellbore for tunnel cleanup. Traditional well fluids have a limited application in depleted reservoirs because the lowest achievable density is on the order of 6.6 lbm/gal. In many depleted reservoirs, this density can represent an overbalance. It is not always desirable or operationally practical to provide this underbalance with a gas cushion; therefore, to achieve underbalance, it is desirable to engineer a stable fluid with nondamaging chemical properties, which would have a significantly lower density. This paper reports on the formulation of superlight completion fluids consisting of Shell Sarapar 147 synthetic oil (SO) [Shell Middle Distillate Synthesis (MDS), Kuala Lumpur) and 3M Scotchlite hollow-glass spheres (HGSs) (3M, St. Paul, Minnesota, USA), also known as glass bubbles, as a density-reducing agent, with an appropriate stabilizing agent. Laboratory tests show that density values as low as 5.0 lbm/gal could be achieved. Similar mixtures were prepared and used in perforation operations for Talisman Malaysia. A total of 72 bbl of lightweight completion fluids (LWCFs) at approximately 5.5 lbm/gal was pumped downhole, and the perforation job was completed successfully. Production history of the well shows marked increase in production rate compared to the neighboring wells, which produce from the same reservoir but were perforated traditionally with little or no underbalance. This technology is not necessarily limited to depleted reservoirs. In normally pressured zones where permeability is extremely low, the fluid provides an opportunity to increase the available underbalance by an order of magnitude to assist cleanup.
Analysis of Casing-Shift Problems in Compacting Reservoirs
Authors: Jinnai Yasuo , Morita Nobuo 
Published: June 2009

Summary
In the past, casing-shift problems were thought to be one of the causes of production decline. This motivated field engineers to investigate whether or not casing shift occurred by shooting radioactive bullets in productive layers and measuring the relative movement of casing and formation (Allen 1984). However, the results were ambiguous because of the uncertainty of wireline-logging depth measurements during a long reservoir-compaction period. In this paper, the following will be investigated:
How the bonding of casing and formation breaks under confining stresses How a casing slides after the bonding breaks The magnitude of shear force required to induce casing shift The magnitudes of casing shift for typical reservoir conditions
To achieve the above objectives, the following laboratory measurements were performed:
Construct test samples simulating casings bonded to formation with cement and mudcake. Conduct experiments measuring shear force required to induce casing shift under confining stress. Simulate the correlation of depth and shear and normal stresses around a cased hole using a finite-element model for compacting reservoirs. Compare the results of experiments with simulations to judge the magnitude of casing shift.
The laboratory experiments showed that a casing does not simply slip when a shear load is applied. It accompanies shear failure of cement sheath. Hence, when casing shift occurs, shear fractures are also induced in the cement, which may cause gas or liquid migration through the fracture network. Calculations are performed to estimate the shear stress induced at casing/cement and formation/cement interfaces during reservoir compaction using a finite-element-simulation model. Comparing the laboratory-measured sliding shear stress with the calculated shear stress, it is concluded that a small casing slippage may occur at casing/cement and formation/cement interfaces. The amount and distribution of slippage along casing/cement and formation/cement are also evaluated for typical reservoir conditions. The small slippage may be serious enough to reduce production. Hence, reperforation at the expected shift intervals would recover productivity. In addition, the small slippage creates a shear fracture network that may cause gas or liquid migration.
Several standard cement tests are described in Nelson and Guillout (2007). This work complements two previous works (Evans and Carter 1963; Ladva et al. 2004) for casing/cement and formation/cement bond strengths using similar cement. Previous work determines cement shear and hydraulic-bond strengths for those with small reservoir compaction, while this work focuses on cement-bond strength for more-severe compactions where casing slippage or failure are initiated. Unlike the standard hydraulic and shear cement bond tests, the current test method closely simulates the in-situ conditions, clarifying the phenomena occurring during casing slippage. In addition, a rule of thumb and a practical method to evaluate the magnitude of casing shift are proposed.
Measurement and Analysis of Induced Torsion in Helically Buckled Tubing
Authors: Zdvizhkov A. , Miska S. , Mitchell R. 
Published: June 2009

Summary
In the original publication on helical buckling by Lubinski et al. (1962), it was assumed that no torsion can be developed in buckled tubular string (Lubinski–Woods problem) if there is no casing-to-tubing friction and tubing remains in an elastic range of bending.
Recent theoretical work by Mitchell (2004) presented the large-displacement analysis of a helically buckled slender beam and predicted that shear force and twisting moment are induced in helically buckled pipe without externally applied torque.
In short, there is an induced left-hand torsion in tubing buckled into a right-hand helix that is surprisingly large and, in some cases, may approach or exceed the makeup-torque values for connections.
For study of this phenomenon, an experimental facility was set up at the University of Tulsa, depicting a straight horizontal wellbore with the inner steel tubing having a 0.50-in. (12.7-mm) outside diameter (OD) and the outer acrylic tube having a 1.90-in. (48.3-mm) inside diameter (ID), representing drillstring and wellbore, respectively.
For a precise measurement of pure torsion in the tubing, strain gauges were employed, arranged into the full-torsion bridge configuration.
The experiments were performed with the "bottom end" of the steel tubing held stationary and with axial-buckling force applied from the "top end."
The end conditions for the tubing were represented by clamped and pinned connections.
It was observed that torsional equilibrium in the tubing is disturbed as soon as buckling force is applied, with further increase in torsion as the shape of the tubing transforms from sinusoidal to helical.
Upon the tubing reaching full helical shape, the internal torsion continues to increase with the increase of axial-buckling force in the manner predicted theoretically.
The results of this study are important for practical design and analysis of drillstrings and completion tubing.
Some factors affecting the creep behaviour of metallic materials processed by equal-channel angular pressing
Authors: Sklenička Václav , Dvořák Jiří , Král Petr , Svoboda Milan , Saxl Ivan 
Published: June 2009

Abstract
Very few reports describing the creep behaviour of materials processed by equal-channel angular pressing (ECAP) have shown that there are both similarities and differences between the creep behaviour of coarse-grained metals and alloys and their ultrafine-grained counterparts. This paper examines these differences and evaluates some factors affecting the creep behaviour of pure aluminium, pure copper, and the binary Al-0.2 wt.% Sc alloy processed by ECAP. It was found that the creep behaviour of pressed material depends strongly on the number of ECAP passes and successive passes result in a gradual decrease in the creep resistance which may be attributed to microstructural changes, homogenization of the microstructure and the microtexture, nanoporosity induced by the ECAP procedure and thermal instability of the pressed material during creep exposure.
Nanostructuring of metallic materials by spd processing for advanced properties
Authors: Valiev Ruslan 
Published: June 2009

Abstract
During the past decade, fabrication of bulk nanostructured metals and alloys using severe plastic deformation (SPD) has been evolving as a rapidly advancing direction of nanomaterials science and technology aimed at developing materials with new mechanical and functional properties for advanced applications. The principle of these developments is based on grain refinement down to the nanoscale level via various SPD techniques. This paper is focused on recent studies of SPD processing regimes and routes enabling fabrication of ultrafine-grained metals and alloys. The paper also considers nanostructural features of SPD-processed materials that are responsible for enhancement of their properties.
Synchrotron X-ray line-profile analysis experiments for the in-situ microstructural characterisation of SPD nanometals during tensile deformation
Authors: Kerber Michael B. , Schafler Erhard , Wieczorek Arkadiusz K. , Ribarik Gabor , Bernstorff Sigrid , Ungar Tamas , Zehetbauer Michael J. 
Published: June 2009

Abstract
There is a great interest in the understanding of mechanical properties of nanocrystalline materials, especially of those processed by severe plastic deformation, since those exhibit both high strength and considerable ductility. A special setup for X-ray line profile analysis was developed for monitoring the microstructural evolution of in-situ tensile tests of high pressure torsion deformed samples. A comprehensive evaluation procedure is presented which allows the determination of several physical microstructural parameters. This includes a careful estimation of the error of the evaluation procedure. As an example, nickel shows a slight decrease of the size of the coherently scattering domains while the dislocation density tends to increase. The dislocation arrangement exhibits strain-field-screening of neighboring dislocations and an equal amount of screw and edge dislocations.
Tensile and fatigue properties of sub-microcrystalline ultra-low carbon steel produced by hpt-straining
Authors: Todaka Yoshikazu , Nagai Hironori , Takubo Yosuke , Yoshii Miki , Kumagai Masaaki , Umemoto Minoru 
Published: June 2009

Abstract
The tensile and fatigue properties of ultra-low carbon steel after HPT-straining at a rotation-speed of 0.2 rpm under a compression pressure of 5 GPa were investigated. Elongated grains with 300 nm thickness and 600 nm length with high dislocation density were formed by the HPT-straining. The obtained Vickers microhardness was around 3.6 GPa. The engineering tensile strength of the HPT-processed ultra-low carbon steel for 5 and 10 turns was 1.9 GPa, which is similar to the value of maraging high-alloy steels. The elongation increased with strain (at 5 to 10 turns). The increase in elongation is caused by the reduction of the stress concentration due to the existence of continuously recrystallized grains. The fatigue strengths of HPT-processed specimens were twice as high as those of the 90 % cold-rolled specimen in the low-cycle fatigue region, whereas in the high-cycle fatigue region the fatigue strengths were not so different due to the high notch sensitivity of the HPT-processed specimens.
The characteristics of superplastic flow in a magnesium alloy processed by ECAP
Authors: Figueiredo Roberto B. , Langdon Terence G. 
Published: June 2009

Abstract
It is well known that Equal-Channel Angular Pressing (ECAP) introduces an ultrafine grain size and leads to exceptional superplastic properties in a ZK60 (Mg-5.5 % Zn-0.5 % Zr) alloy. This paper presents an analysis of the flow behavior during superplastic deformation in the ZK60 alloy. It is shown that an increase in the ECAP processing temperature enhances the thermal stability of the grain structure. In addition, the optimum superplastic properties occur at higher strain rates when testing at higher temperatures thereby introducing the potential for achieving high strain-rate superplasticity.