bluuebunny/crossref_metadata_2025 huggingface dataset:
Epidermal Growth Factor Receptor Monoclonal Antibodies for the Treatment of Metastatic Colorectal Cancer
Authors: Jean Gary W. , Shah Sachin R.
Published: May 2008

Treatment of metastatic colorectal disease has evolved over the last decade. Two epidermal growth factor receptor (EGFR) monoclonal antibodies—cetuximab and panitumumab—have been developed in an effort to provide yet another therapeutic option. The EGFR is a transmembrane glycoprotein, expressed constitutively throughout the body and found on many epithelial tissues. The monoclonal antibodies bind to and inhibit the activation of the receptor in the body. This inhibition prevents tumor cell growth, angiogenesis, invasion, and metastasis, and induces apoptosis. Cetuximab and panitumumab exhibit nonlinear pharmacokinetics. Both monoclonal antibodies are approved for the treatment of refractory metastatic colorectal cancer. Cetuximab in combination with irinotecan has significantly better response rates and progression‐free survival compared with those of cetuximab or irinotecan alone. Cetuximab and panitumumab as monotherapy have shown significantly better response rates and progression‐free survival compared with best supportive care in patients refractory to irinotecan and oxaliplatin. In the Cetuximab Combined with Irinotecan in First Line Therapy for Metastatic Colorectal Cancer (CRYSTAL) trial, treatment‐naïve patients received cetuximab in combination with the chemotherapy regimen infusional leucovorin, fluorouracil, and irinotecan (FOLFIRI) or FOLFIRI alone; the difference in progression‐free survival was statistically significant but suggested only a modest benefit over FOLFIRI alone (8.9 vs 8 mo, p=0.036). Results of a preplanned analysis of the first 231 events in the Panitumumab Advanced Colorectal Cancer Evaluation (PACCE) trial favored the control group (chemotherapy regimen with folinic acid [leucovorin], fluorouracil, and oxaliplatin [FOLFOX] plus bevacizumab) instead of the control group plus panitumumab. For clinical consideration, many trials have shown that the intensity or absence of EGFR expression is not a clinically significant predictor of outcomes. Development and intensity of a rash are suggested to be a positive predictor of outcomes in patients. The most common adverse events of EGFR monoclonal antibody therapy are rash, diarrhea, and hypomagnesemia. Other serious but not common adverse events include hypersensitivity reactions and pulmonary toxicity. The availability of EGFR monoclonal antibodies has provided another weapon in the arsenal to treat refractory metastatic colorectal cancer. They have shown safety and efficacy in combination with other chemotherapy regimens and as monotherapy; however, their use as metastatic colorectal cancer therapy needs to be further explored.
Pharmacogenetic Testing for Uridine Diphosphate Glucuronosyltransferase 1A1 Polymorphisms: Are We There Yet?
Authors: Perera Minoli A. , Innocenti Federico , Ratain Mark J.
Published: May 2008

Recent changes to the labels of three prescription drugs—irinotecan, 6‐mercaptopurine, and warfarin—include recommendations for pharmacogenetic testing in patients. Thus, clinicians are faced with determining the utility and practicality of pharmacogenetic testing in clinical practice. We illustrate the clinical implications that this testing may have using irinotecan, an agent approved for the treatment of metastatic colorectal cancer, as an example. A clinical association between the drug's active metabolite and toxicity has been found. By performing uridine diphosphate glucuronosyltransferase (UGT) 1A1 genetic testing, some studies have been able to predict which patients receiving irinotecan will experience the toxicity. Thus, irinotecan's package insert was revised to include a recommendation for such testing. In addition, the United States Food and Drug Administration approved a clinical test for theUGT1A1*28allele. These events demonstrate that pharmacogenetics has entered the realm of clinical practice. However, the transition from bench to bedside of these tests has distinct challenges such as population differences, test sensitivity, and the role of other genetic and nongenetic factors that influence drug toxicity. In addition, ethical and logistic implications of pharmacogenetic testing exist.
Ethylglucuronide as a Biomarker for Ethanol Detection
Authors: Kissack Julie C. , Bishop Jaime , Roper Amber Leatherwood
Published: May 2008

Many different biomarkers can be used to evaluate ethanol intake. Ethylglucuronide, a minor metabolite of ethanol, is a biomarker that is useful in determining ethanol intake up to 80 hours after ethanol consumption. To better understand the utility of this biomarker, a MEDLINE search of ethylglucuronide in the English‐language literature from January 1987‐August 2007 was performed; clinical trials and case reports were reviewed. In addition, relevant nonmedical media and government documents were reviewed. Ethylglucuronide has an extended window of detection compared with other biomarkers and can be detected in urine 1 hour after ethanol ingestion. However, incidental exposure to ethanol‐containing products may cause false‐positive results, and false‐negative results have been reported when urine has been infected with certain bacteria that cause urinary tract infections. Before a urine sample is submitted for ethylglucuronide evaluation, a thorough drug history should be obtained. Misinterpretation of ethylglucuronide results can produce serious adverse medical and social consequences. When positive ethylglucuronide screen results are reported, further evaluation of the clinical picture and confirmation with ethylglucuronide quantification and self‐report should be instituted. Clinicians should have a thorough understanding of the strengths and weaknesses of the ethylglucuronide test when used in various settings.
Successful Use of Reduced‐Dose Efavirenz in a Patient with Human Immunodeficiency Virus Infection: Case Report and Review of the Literature
Authors: Torno Mauro S. , Witt Mallory D. , Saitoh Akihiko , Fletcher Courtney V.
Published: May 2008

Efavirenz, a nonnucleoside reverse transcriptase inhibitor, is a highly effective and widely prescribed antiretroviral agent. It is recommended as first‐line treatment of human immunodeficiency virus (HIV) infection. The standard dose of efavirenz is 600 mg/day; however, adverse central nervous system effects limit its use. Few data citing use of efavirenz at lower doses have been published. We describe a 35‐year‐old man with HIV infection whose virologic suppression was maintained after 18 months of treatment with efavirenz 400 mg/day. Genetic testing for cytochrome P450 (CYP) 2B6 showed that the patient was a heterozygous variant; patients with this polymorphism tend to have higher plasma efavirenz concentrations and slower plasma efavirenz clearance (prolonged elimination half‐lives). Therapeutic drug monitoring also supported the dose reduction in this patient. Even with the 400‐mg dose, the patient's plasma trough concentrations exceeded the upper limit of the therapeutic range. However, as he remained completely asymptomatic with this dose, no further dose reduction was necessary. This case report provides evidence that reduced efavirenz doses may be effective in the treatment of HIV infection. In addition, this case demonstrates that pharmacogenetic and pharmacokinetic testing combined with therapeutic drug monitoring may be used to guide reduced‐dose, efavirenz‐based therapy.
Management of Chronic Nonmalignant Pain with Nonsteroidal Antiinflammatory Drugs
Authors: Herndon Christopher M. , Hutchison Rob W. , Berdine Hildegarde J. , Stacy Zachary A. , Chen Judy T. , Farnsworth David D. , Dang Devra , Fermo Joli D.
Published: May 2008

Chronic nonmalignant pain is a major burden on the health care system in the United States. Frequently, nonsteroidal antiinflammatory drugs (NSAIDs) are used to assist in the management of various chronic pain syndromes. Although evidence is accumulating on the potential toxicities associated with NSAIDs, clear recommendations are lacking to guide the appropriate use of these drugs. Equivocal data, especially with respect to cardiovascular risk, further confuse a clear treatment pathway when assessing pharmacotherapy. Originally, cyclooxygenase selectivity appeared to be a determining factor in choosing an agent because of the presumed lack of effect on the cardiovascular and gastrointestinal renal systems. This theory, however, was recently dispelled. To provide guidance on the selection of an NSAID for various chronic pain syndromes, members of the Ambulatory Care, Cardiology, and Pain and Palliative Care Practice and Research Networks of the American College of Clinical Pharmacy evaluated evidence‐based use of NSAIDs for frequently encountered pain syndromes, with special focus on the adverse effects of this class of agents.
The continuous strength method
Authors: Gardner L.
Published: May 2008

Many of the principal concepts that underpin current metallic structural design codes were developed on the basis of bilinear (elastic, perfectly-plastic) material behaviour; such material behaviour lends itself to the concept of section classification. The continuous strength method represents an alternative treatment to cross-section classification, which is based on a continuous relationship between slenderness and (inelastic) local buckling and a rational exploitation of strain hardening. The development and application of the continuous strength method to structural steel design is described herein. Materials that exhibit a high degree of nonlinearity and strain hardening, such as aluminium, stainless steel and some high-strength steels, fit less appropriately into the framework of cross-section classification, and generally benefit to a greater extent from the continuous strength method. The method provides better agreement with test results in comparison to existing design codes, and offers increases in member resistance and a reduction in scatter of the prediction. An additional benefit of the proposed approach is that cross-section deformation capacity is explicitly determined in the calculations, thus enabling a more sophisticated and informed assessment of ductility supply and demand. Further developments to the method are under way.
Passive fire protection of concrete structures
Authors: Khoury G. A.
Published: May 2008

Passive fire protection of concrete structures is chiefly aimed at combating explosive thermal spalling, which relies on two underlying mechanisms: (a) the build-up of pore pressures and (b) the development of thermal stresses. The former could be alleviated, or eliminated, by the use of polypropylene (PP) fibres in the mix. Thermal stresses could be reduced by the use of thermally stable aggregates of low thermal expansion—not always practical when the choice of aggregates is limited at the location in question. The second, more effective, but much costlier solution is the use of thermal barriers that reduce the heat flow into the substrate concrete and hence reduce concrete temperature (and the resulting pore pressures and thermal stresses). Thermal barriers, therefore, address both underlying mechanisms of explosive thermal spalling. Criteria for determining the thickness of thermal barriers are currently based on specified maximum temperatures at the barrier/concrete interface. This is fundamentally flawed. The current author proposes that authorities should consider instead other criteria, which would include the heating rate at the interface (because explosive spalling is more a function of heating rate than maximum temperature) as well as permeability (strength), silica fume content, initial moisture content and, if possible, aggregate type. This approach is scientifically more correct and provides a more conservative (i.e. safer) result. In new designs, a judicial cost-effective use of both thermal barriers and PP fibres is recommended.
Investigation of the corrosivity of some water-glycol hydraulic fluids to stainless steel 316L for subsea applications
Authors: Zheng Lei , Neville Anne
Published: May 2008

Water-glycol solutions (HFC) [1] are one of the most commonly used hydraulic fluids in applications where fire hazard is a concern such as in the offshore oil industry. However they may cause corrosion failures of components in electro-hydraulic control systems that can have serious consequences for the operation of an entire subsea oil recovery system. The principal objective of this study is to assess the corrosion behaviour of the main material of construction used for the components in such systems (Stainless Steel 316L) in a range of commercial water-glycol hydraulic fluids (Oceanic HW443, HW525, HW540, HT, EE1), and to find out the probable factors that may affect the corrosivity of each fluid.

The corrosivity of each fluid was ranked according to the breakdown potential obtained from cyclic potentiodynamic polarization (CPP) tests [2]. Gas chromatography-mass spectroscopy (GC-MS) analysis was carried out to assess the components of the different organic additives in each fluid and the water percentage of each fluid was determined by Karl Fischer titration. A comparison of relative ethylene glycol content has indicated that the higher the concentration of ethylene glycol the more corrosive the fluid is to stainless steel 316L if the additive package is the same. However, additive packages dominate the corrosivity.
Erosion-corrosion of pipeline steel X65 and 22Cr duplex stainless steel in CO2 saturated environment
Authors: HU Xinming , Neville Anne
Published: May 2008

An erosion-corrosion study on pipeline material degradation in sand-containing and CO2 saturated environments has been carried out. The total material loss, corrosion, erosion and their interactions (often referred to as synergy) have been assessed for pipeline steel X65 and 22Cr duplex stainless steel in various environmental conditions (temperature, flow velocity and sand content). The experimental results show the 22Cr duplex stainless steel exhibits a better performance under liquid-solid impingement for all conditions resulting from the better resistance to corrosion related degradation. A comparison between the experimental data and the empirical prediction model developed in this work shows a good correlation.
Study of the Effect of Inhibitor on Erosion-Corrosion in CO2-Saturated Condition With Sand
Authors: Neville A. , Wang C.
Published: May 2008

CO2 corrosion inhibitors are widely adopted in production and processing facilities in the oil and gas industry. The challenge is that under multiphase flow (liquid/sand) and high shear stress conditions, successful application of inhibitors can be difficult. Under such severe erosion-corrosion conditions, the total material damage is identified as being associated with electrochemical corrosion, solid particle erosion and synergistic effects between the two.

To investigate the possibility of using corrosion inhibitors to reduce erosion-corrosion, this study has characterized the corrosion phenomena occurring at the carbon steel-electrolyte interface under erosion-corrosion conditions. AC impedance was used to provide mechanistic information of corrosion with absence and presence of a commercial corrosion inhibitor in erosion-corrosion conditions in a CO2-saturated brine. Experiments were conducted using a Rotating Cylinder Electrode cell containing sand at different temperatures, rotational speeds and with various inhibitor concentrations. Four commercial inhibitors have been investigated.

In this work the potential for applying corrosion inhibitors for the reduction of material loss in erosion –corrosion is assessed and the role of the inhibitor in reducing corrosion, erosion and interactive mass loss mechanisms is discussed.
Inhibition Performance of a New Series of Mono/Diamine-Based Corrosion Inhibitors for HCl Acid Solutions
Authors: Al-Taq Ali A. , Ali Shaikh A. , Nasr-El-Din Hisham A
Published: May 2008

New monoamine and diamine compounds were synthesized from dodecylamine and 1, 12-dodacanediamine, and evaluated as acid corrosion inhibitors for low-carbon steel. The inhibition behavior of these compounds was examined using gravimetric and electrochemical methods (linear polarization and Tafel plot). Weight loss tests were conducted in 1M HCl at 140°F for six hours. To simulate acid stimulation treatments, other weight loss tests were conducted using typical acid stimulation concentrations 4.1 and 7.7 M HCl, (equivalent to 15 and 28 wt%, respectively) at 140°F for two hours. The effects of corrosion inhibitor type and concentration, and acid concentration were investigated.

Experimental results indicated that examined monoamine compounds exhibited better corrosion inhibition for low-carbon steel in 1 M HCl acid solution than their corresponding diamine compounds. This behavior was clearly observed at a low corrosion inhibitor concentration of 50 ppm. Tafel Plot results suggest that the inhibition mechanism for all examined compounds involved a simple reaction site blocking. For both monoamine and diamine compounds, the inhibition performance was found to increase with increasing corrosion inhibitor concentration and decrease with acid concentration.

Aromatic and multiple bonds substituents introduced to monoamine and dimamine compounds were found to enhance inhibition performance compared to the starting materials (dodecylamine and 1, 12-dodacanediamine). This is attributed to the π-electrons present in aromatic and multiple bonds substituents. Both dodecylamine derivatives with a triple bond or an aromatic substituent exhibited excellent protection in 4.1 M HCl. However, the derivative with a triple bond showed the best protection (98%) at 7.7 M HCl. This result is very promising and suggests that this corrosion inhibitor has a good potential to be used as a corrosion inhibitor in oil/gas wells acid stimulation treatments.
Hydrothermal Chemistry of Formate Brines and Its Impact on Corrosion in HPHT Wells
Authors: Howard S. K. , Downs J. D.
Published: May 2008

Formate brines have been successfully used in hundreds of HPHT drilling and completion operations over the past 12 years and have exhibited remarkable thermal stability. This has been confirmed by analyses of brines recovered from extreme HPHT wells after lengthy exposure (months/years). Laboratory testing cited in the literature has, however, indicated that significant formate brine decomposition to bicarbonate and hydrogen gas should occur at even relatively low temperatures if the brine is in contact with catalytic surfaces. The potential damage that such decomposition and the evolution of decomposition products could cause to metallic materials has caused concern in the industry.

The inconsistency between laboratory and field behavior has indicated that standard laboratory autoclaves are not suited for reproducing or simulating downhole conditions. Typical differences between these two environments are pressure, presence of gas cap, and amount and type of catalytic surfaces. In order to better simulate actual downhole conditions, experiments have been carried out in specialist equipment developed to examine hydrothermal chemistry. A non-catalytic gold test cell was used for the decomposition testing, immersed in a high pressure high temperature autoclave filled with water.

The flexibility of the gold cell has allowed experiments to be conducted and sampled at high pressure without the presence of an artificial gas cap. Initial tests have shown that any decomposition reactions taking place in formate brine under hydrothermal conditions will reach equilibrium with bicarbonate. This discovery has also given us useful information on how to formulate bicarbonate-rich formate brine compositions which remain stable even at very high temperatures. As bicarbonate is an important component in buffered formate brines, these formulations are not much different from the current brines already in field use.

Analyses of a range of formate brine samples that have been recovered from two HPHT wells have confirmed that formate reaches equilibrium with bicarbonate over time under hydrothermal conditions.

This paper reviews what has been learnt about formate decomposition under realistic hydrothermal conditions, and exposes new information on how the equilibrium reactions might impact on metal integrity and corrosion processes in HPHT wells.

The most important lesson learned from testing in the flexible gold cell is that traditional laboratory autoclaves operated with a gaseous head space are not suited for testing formate brines at high temperatures. In fact, test results generated in such autoclaves will be laboratory artifacts that do not simulate or reproduce what actually happens in HPHT wells.
Increasing the Life of Flare Tips
Authors: Fox A. B. , Huang Yan Yan , Rafik Dena , Williamson J. , Lindley T. C. , Lee P. D.
Published: May 2008

Flare tips are essential for safety. Maintenance is difficult and costly. Flare tips are subjected to high combustion temperatures, thermal cycling, oxidation and marine corrosion. Following a number of flare tip failures an in depth study by Imperial College was carried out into the failure of a flare tip from a UK platform, looking for service life improvement. Materials selection and design solutions were considered. The study considered alternative materials and concluded that materials selection was the smaller part of the answer; design changes can double service life. This study used failure investigation, high temperature experimental and thermo-mechanical modelling analysis.

The modelling process simulated two common flaring conditions and correctly predicted the observed failure of initiation and crack propagation from holes used to bolt on flame stabilizing plates to the top of the flare. The calculated thermal stress and strains enabled the low cycle fatigue life and minimum creep life to be predicted. It was concluded that service life could be improved by replacing Incoloy alloy 800HT (UNS N08800) with Inconel alloy 625 (UNS N06625), an alloy with attractive mechanical properties and improved high temperature corrosion resistance. Repositioning or eliminating bolt holes can double service life.
The Role of Packer Fluids in the Annular Environmentally Assisted Cracking of CRA Production Tubing
Authors: McKennis J. S. , Termine Enrico J. , Bae N. S. , Kimura M. , Shimamoto K. , Sato H.
Published: May 2008

The increased use of corrosion resistant alloys (CRAs) in deep HPHT wells has led to production-tubing cracking failures throughout the industry. Many of these failures have occurred from the outside (annulus side) and been attributed to Environmentally Assisted Cracking (EAC) and hence, best described as Annular EAC (AEAC). Examination of these failures points to a serious incompatibility of the production tubing metallurgy with the packer fluid under stress.

To solve this problem, combined expertise in fluid chemistry and metallurgy is needed. Consequently, in 2003 a research alliance of the co-authors to examine the compatibility of a wide spectrum of completion fluids with various martensitic stainless steel metallurgies was established.

This unique research collaboration leading to extensive stress cracking testing performed with different metallurgies and different fluids under simulated well conditions has resulted in an extensive database and new body of knowledge regarding the causes behind AEAC failures. With respect to the mechanisms of failure, a variety of contaminants in completion/packer fluids have been found to play a dominant role. Such contaminants include sulfur-containing species, oxidants, and select ionic species. This paper addresses the impact of the new information and identifies serious misconceptions regarding the role of completion & packer fluids in the tubular failures.

The information accrued from this comprehensive study has advanced the industry's knowledge of the causes of AEAC by detailing the previously unrecognized importance of various contaminants present in the fluids. Importantly, it has led to the recognition of the need for quality assurance and best-practice fluid management throughout the life cycle of the fluids. The extensive database and a user friendly software program derived from it permit minimization of tubular failure risk by matching packer fluids with metallurgies under a wide variety of stipulated well conditions.
Cathodic protection system life assessment
Authors: Buxton D C , John D G
Published: May 2008

The North Sea environment is a harsh environment and cathodic protection is typically applied to offshore steel platforms to control degradation by corrosion. As offshore platforms near the end of their design life, the cathodic protection systems, either galvanic anodes or impressed current systems, may also be reaching the end of their life. Where the platform life is extended, it is necessary to consider whether the existing cathodic protection systems are fit-for-purpose for the intended life extension period.

Over the past few years the condition of a hybrid cathodic protection system, which comprises both galvanic anodes and seabed impressed current anodes, on one North Sea platform has been investigated and assessed. This has included regular performance assessment, specific assessment of anode wastage and estimates of remaining life. The aim of the assessment was to predict when extensive retrofit activity might be required, thus avoiding unnecessary corrosion degradation and enabling any retrofit work to be scheduled in advance.

Modeling processes can be used in the cathodic protection life assessment to provide a better understanding of the existing protection system and to predict future performance.

The assessment has demonstrated that the platform is satisfactorily protected from corrosion and that extensive retrofit work is not expected to be required in the short term.
A Predictive Model for Microbial Induced Corrosion (MIC) in Sub-sea Production Pipelines: Part 1—Abiotic Corrosion Model
Authors: Smith P. , Roy S. , Swailes D. , Maxwell S. , Page D. , Lawson J.
Published: May 2008

Microbial Induced Corrosion (MIC) is a very aggressive form of corrosion with many proposed mechanisms but as yet there is no internationally agreed mechanism for its action. Rapid pitting attack can quickly lead to equipment failure, which is a particular problem in the petrochemical industry where the effects of MIC are prevalent. MIC is a highly complex process but it is believed that Sulphate Reducing Bacteria (SRB) perform a major role. SRB present in anaerobic layers of biofilms at the metal surface can be detected at corrosion sites in the field by the presence of sulphide films. The models currently used to predict MIC offer only a semi-quantitative assessment of MIC and are often unpredictable as they do not often include knowledge of SRB activity or biofilm growth rates.

The aim of this investigation is to develop a physical model for the prediction of corrosion rates associated with MIC in subsea production pipelines. The model will include abiotic and biotic corrosion parameters and is based on heterogeneous reactions at the steel surface, a species concentration profile described by the Nernst diffusion layer model, and overall anodic and cathodic current densities balancing each other. Presented in this publication is an initial abiotic model based on a simple corrosion system of pipeline steel exposed to an electrolyte of deaerated low conductivity water. The corrosion system is examined experimentally using potentiodynamic polarisation techniques, a glass corrosion cell and a three electrode potentiostat system. An abiotic model is then developed for this corrosion system and the model prediction compared to the experimental data. The model is shown to be in reasonable agreement with the experimental data.
The Use Of Carbon Steel in Highly Sour Oil and Gas Production Systems
Authors: Johnson B. V. , Al-Ghafri M. J. H. , Al-Harthy A. S. M. , Kompally S. N. , Dicken G. , Schofield M. J. , Bruce K. , John D. G.
Published: May 2008

The application of standard corrosion modelling systems for carbon steel (CS) for a number of highly sour oil & gas projects has predicted corrosion rates ranging from 10 to 35 mm/yr which drives material selection to corrosion resistant alloys (CRAs). This is the case even where corrosion inhibitors are considered with overall effectiveness in the range 90 to 95% (where effectiveness = efficiency x application time). In order to validate the model predictions a series of laboratory corrosion tests were carried out using a CS pipeline material to establish whether the natural formation of protective iron sulfide corrosion products can be demonstrated to provide satisfactory protection. If this was the case then it would enable CS to be considered either with or without corrosion inhibition and would avoid the need to use expensive CRAs and could result in cost savings of hundreds of millions of US dollars.

The paper describes short term studies to assess the feasibility of this approach. Tests have been conducted under simulated dynamic production environment conditions ranging in temperature from 50 to 210°C with partial pressures of H2S up to 11 bara. Both formation and condensed water systems have been simulated.

The degree of protection afforded by scales formed in these conditions has been characterised by electrochemical evaluation and by gravimetric analysis of coupons from Rotating Cylinder Electrode (RCE) and rotating cage apparatus. The morphology of the scale has been studied under the Scanning Electron Microscope (SEM) and analysed by Energy Dispersive X-rays (EDX) and X-ray Diffraction (XRD. Natural corrosion rates from these short term tests are significantly lower than predicted with measured rates of between 0.04 to 2.2 mm/yr (i.e. laboratory values ranging from 16 to 900 times lower than predicted). This laboratory data indicates that CS is potentially suitable for field service and further selective long term tests with and without corrosion inhibitor are planned to confirm these results.
Corrosion Management For Aging Pipelines — Experience From the Forties Field
Authors: Marsh J , The T , Ounnas S , Richardson M
Published: May 2008

In 2003, Apache became the operator of the Forties Field. The field has now been in operation for 33 years and much of the infield pipeline system has exceeded its original design life of 20-25 years. Apache intend to continue production in the Forties Field for, potentially, in excess of a further 20 years. As such, they have identified numerous issues with respect to corrosion management of the infield pipeline system. Since late 2006, the Forties Field infield pipeline corrosion and integrity management has been carried out by IONIK Consulting/JP Kenny Caledonia ltd. Working closely with Apache, the infield pipeline system has been reviewed, a number of issues have been assessed and quantified and practices with respect to corrosion management, corrosion monitoring and inspection have been implemented. This document examines the issues identified, the corrosion management strategy put in place, and the inspection actions undertaken. Examples of issues identified with respect to corrosion management systems include a requirement for a dedicated pipeline corrosion management strategy, pipeline corrosion modelling, a corrosion risk assessment of the pipeline system, a review of corrosion inhibition and pigging, and a review of key performance indicators with emphasis on pipeline management. Specific corrosion issues identified include anode depletion, preferential weld corrosion, localised corrosion and 6 o’clock corrosion. Examples of other factors identified have been potential risks from microbial and under deposit corrosion due to low flow rates. This publication provides an overview of these issues and the implementation of solutions, alongside changes to items such as documentation and modification of existing procedures, risk assessment, corrosion management, and the implementation of an intelligent pigging program.
Role of Pressure and Reaction Time on Corrosion Control of H2S Scavenger
Authors: Zea Luis , Jepson Paul , Kumar Ranganathan
Published: May 2008

Sulfite cracking, corrosion fatigue and electrochemical corrosion are some examples of the effects of the presence of Hydrogen Sulfide in a mixture of oil and brine. In order to guard pipelines and well equipment, it is necessary to reduce the concentration of this gas to a minimum. One of the best solutions to do so is utilizing a chemical H2S scavenger. It is of high interest to identify the role that the pressure and reaction time parameters play on the H2S scavenger efficiency. To address this concern, this paper experimentally evaluates the change of the scavenger capacity to react with Hydrogen Sulfide at different pressures. Additionally, the gas concentration is examined as reaction time passed in order to identify its effect on the scavenger performance. Results indicate that most of the scavenger- H2S reaction occurs in the first five minutes and that lowering the pressure after the reaction has started taking place decreases the scavenger efficiency. Scavenger concentration was also a variable and it was found that a 600:1 ratio is above recommendable parameters since a higher amount of scavenger is used without this meaning a significant decrease of Hydrogen Sulfide concentration.
Contingent responses of mothers and peers to indirect and direct aggression in preschool and school‐aged children
Authors: Valles Nizete‐Ly , Knutson John F.
Published: May 2008

The primary goal of the study was to determine whether mother and peer's responses to direct and indirect aggression would contribute to children's use of direct and indirect aggression. Using adaptations of the Direct and Indirect Aggression Scale, a multi‐informant strategy, and a sample of disadvantaged families, data were collected from 296 mothers of children ages 4–11, 237 children ages 6–11, and 151 teachers of those children. Mothers and peers were reported to react more harshly in response to direct aggression compared with indirect aggression, and higher rates of direct aggression were associated with reduced popularity. These findings were seen as being consistent with the hypothesis that different forms of aggression result in differential responding by mothers and peers, as well as the notion that direct aggression is a higher cost option than indirect aggression. Results also replicated previous findings that boys tend to use physical aggression more than girls, but girls use indirect aggression more than boys. Finally, low IQ was correlated with higher direct aggression in girls but had no relation with aggression in boys. Aggr. Behav. 34: 497–510, 2008. © 2008 Wiley‐Liss, Inc.
Fish consumption and body burden of organochlorines among lower hudson urban anglers
Authors: Morland Kimberly , Wolff Mary , Bopp Richard , Godbold James , Landrigan Philip
Published: May 2008

Background

Polychlorinated biphenyls and other organochlorines have contaminated the Hudson River and New York/New Jersey Harbor for many decades. Although body burdens and health effects resulting from exposure to these pollutants have been measured in other populations, little is known about anglers from the lower Hudson area.

Methods

Anglers were recruited from fishing clubs and along piers on the lower Hudson River. One hundred twenty‐five participants provided blood samples and questionnaire information. Serum was analyzed at Mount Sinai School of Medicine for organochlorines.

Results

Mean concentration of total PCB congeners was 4.78 µg/L. A non‐significant adjusted mean difference of −0.59 µg/L was observed between local fish eaters and non‐eaters with higher levels among the non‐eaters. Similar negative, but non‐significant associations were observed for p,p'‐DDT, HCB, and β‐BHC. For pp'‐DDE, and several chlordane residues, levels were higher among anglers reporting local fish consumption, but the difference was statistically significant only for TN.

Conclusions

These findings suggest eating fish from the lower Hudson River and NY/NJ harbor is not associated with an increased body burden of PCBs or most other organochlorines. Am. J. Ind. Med. 51:587–594, 2008. © 2008 Wiley‐Liss, Inc.
Complex toe syndactyly with characteristic facial phenotype: A new syndrome?
Authors: Sobreira Nara Lygia Macena , Cernach Mirlene Cecilia S.P. , Brunoni Decio , Perez Ana Beatriz Alvarez
Published: May 2008

Nonsyndromic syndactyly is a common, heterogeneous hereditary condition of webbed fingers and toes that can be cutaneous or bony, unilateral or bilateral. We describe a patient with complex toe syndactyly and oligodactyly, some interesting skeletal hand findings and atypical facial features without other case like this described before. Cenani–Lenz syndrome (CLS) is a rare disorder with total syndactyly and irregular synostosis of carpal, metacarpal and phalanges, it may involve ulna and radius and digital rays may be absent, some of these were described with atypical facial features and one patient had renal hypoplasia and vertebral anomalies but our patient does not have the oligodactyly or syndactyly of the hands that is consistently present in all patients with CLS. The atypical facial features of our patient resemble Kabuki syndrome but oligodactyly and complex syndactyly have not been described in Kabuki syndrome and this patient has normal intelligence, and extreme eyelid defect (resembling ablepharon). Therefore, for our patient, we suggested to treat in a new condition of limb anomalies and atypical face. © 2008 Wiley‐Liss, Inc.
Methionine sulfoxide reductase: A novel schizophrenia candidate gene
Authors: Walss‐Bass Consuelo , Soto‐Bernardini Maria Clara , Johnson‐Pais Teresa , Leach Robin J. , Ontiveros Alfonso , Nicolini Humberto , Mendoza Ricardo , Jerez Alvaro , Dassori Albana , Chavarria‐Siles Ivan , Escamilla Michael A. , Raventos Henriette
Published: May 2008

Methionine sulfoxide reductase (MSRA) is an antioxidant enzyme implicated in protection against oxidative stress and protein maintenance. We have previously reported the association of marker D8S542, located within the MSRA gene, with schizophrenia in the Central Valley of Costa Rica (CVCR). By performing fine mapping analysis, we have now identified a potential three‐marker at risk haplotype within MSRA in the same CVCR sample, with a global P‐value slightly above nominal significance (P = 0.0526). By sequencing the MSRA gene in individuals carrying this haplotype, we identified a novel 4‐base pair deletion 1,792 bases upstream of the MSRA transcription start site. This deletion was significantly under‐transmitted to schizophrenia patients in the CVCR sample (P = 0.0292) using FBAT, and this was replicated in a large independent sample of 321 schizophrenia families from the Hispanic population (P = 0.0367). These findings suggest a protective effect of the deletion against schizophrenia. Further, MSRA mRNA levels were significantly lower in lymphoblastoid cell lines of individuals homozygous for the deletion compared to carriers of the normal allele (P = 0.0135), although significance was only evident when genotypes were collapsed. This suggests that the deleted sequence may play a role in regulating MSRA expression. In conclusion, this work points towards MSRA as a novel schizophrenia candidate gene. Further studies into the mechanisms by which MSRA is involved in schizophrenia pathophysiology may shed light into the biological underpinnings of this disorder. © 2008 Wiley‐Liss, Inc.
Life as a Nanoscale Phenomenon
Authors: Mann Stephen
Published: May 2008

The nanoscale is not just the middle ground between molecular and macroscopic but a dimension that is specifically geared to the gathering, processing, and transmission of chemical‐based information. Herein we consider the living cell as an integrated self‐regulating complex chemical system run principally by nanoscale miniaturization, and propose that this specific level of dimensional constraint is critical for the emergence and sustainability of cellular life in its minimal form. We address key aspects of the structure and function of the cell interface and internal metabolic processing that are coextensive with the up‐scaling of molecular components to globular nanoobjects (integral membrane proteins, enzymes, and receptors, etc) and higher‐order architectures such as microtubules, ribosomes, and molecular motors. Future developments in nanoscience could provide the basis for artificial life.
PLS: A versatile tool for industrial process improvement and optimization
Authors: Ferrer Alberto , Aguado Daniel , Vidal‐Puig Santiago , Prats José Manuel , Zarzo Manuel
Published: May 2008

Modern industrial processes are characterized by acquiring massive amounts of highly collinear data. In this context, partial least‐squares (PLS) regression, if wisely used, can become a strategic tool for process improvement and optimization. In this paper we illustrate the versatility of this technique through several real case studies that basically differ in the structure of the X matrix (process variables) and Y matrix (response parameters). By using the PLS approach, the results show that it is possible to build predictive models (soft sensors) for monitoring the performance of a wastewater treatment plant, to help in the diagnosis of a complex batch polymerization process, to develop an automatic classifier based on image data, or to assist in the empirical model building of a continuous polymerization process. Copyright © 2008 John Wiley & Sons, Ltd.
Numerische Berechnungen zur Untersuchung des Einflusses der Bewehrungsrichtung auf das Last‐Verformungsverhalten von Stahlbetonplatten
Authors: Rüdiger Lars , Keuser Manfred , Berger Johannes
Published: May 2008

Stahlbetonbauteile, insbesondere Stahlbetonflächentragwerke, erfahren i. d. R. mehraxiale Beanspruchungen. Für deren wirklichkeitsnahe Berechnung ist eine angemessene Modellierung des komplexen Materialverhaltens eine unverzichtbare Voraussetzung. Für die detaillierte Untersuchung stellen neben Bauteilversuchen auch numerische Berechnungen und Simulationen ein hervorragendes Instrument dar, insbesondere um einzelne Parameter gezielt variieren zu können. Der vorliegende Aufsatz zeigt die Vorgehensweise für die Berechnung des Last‐Verformungsverhaltens mit Hilfe der Finiten Elemente Methode für einaxial und zweiaxial biegebeanspruchte Stahlbetonplatten. Dabei wird, von realen Versuchen abgeleitet gezeigt, wie die geometrische und physikalische Modellierung erfolgen kann. Hier ist, neben der wirklichkeitsnahen Abbildung des Materialverhaltens von Beton und Betonstahl, die Modellierung des Verbundverhaltens angemessen zu berücksichtigen. Da in Stahlbetonplatten die Richtung der eingelegten Bewehrung nur selten mit der Richtung der Hauptspannungen übereinstimmt, wurde der Einfluss verschiedener Bewehrungsrichtungen untersucht.
Verzinkte Bauteile im Kontakt mit Spanngliedern
Authors: Burkert Andreas , Lehmann Jens , Burkert Annette , Mietz Jürgen , Eich Gerd
Published: May 2008

Um zu klären, unter welchen Umständen eine potentielle Gefährdung von Spannstählen beim Kontakt mit verzinkten Bauteilen gegeben ist, wurden Laborversuche in alkalischen Lösungen und Beton sowie Zeitstandversuche an Spannbetonprobekörpern durchgeführt. Abstandsvariationen im Nahbereich haben nur einen geringen Einfluss auf die Polarisation des Stahls. Ein praxisrelevanter, unkritischer Abstand für den indirekten Kontakt, z. B. über die schlaffe Bewehrung, kann nicht definiert werden. Hinsichtlich des Flächenverhältnisses Stahl : Zink wurde ein signifikanter Einfluss festgestellt. Flächenverhältnisse über 10 : 1 führen nicht zu einer Polarisation in den Bereich der Wasserstoffentwicklung. Die Ergebnisse wurden durch Untersuchungen an realen Spannbetonfertigteilen verifiziert.

Zeitstandversuche unter Wasserstoffbeladung führten an zugelassenen Spannstählen nicht zu Brüchen während der Versuchszeit. Die anschließend ermittelten mechanischen Kennwerte zeigten keine signifikanten Änderungen. Ein indirekter Kontakt von Spannstählen zu verzinkten Einbauteilen ist deshalb als unkritisch zu bewerten. Der direkte Kontakt ist durch Einhaltung des in der DIN 1045‐1 geforderten Mindestabstands von 2 cm sicher auszuschließen.
Langzeitmessungen an einer Eisenbahnbrücke
Authors: Geier Roman , Österreicher Michael , Pircher Martin
Published: May 2008

In den vergangenen Jahrzehnten haben sich die Möglichkeiten zur Bauwerksüberwachung deutlich weiterentwickelt. Zahlreiche Anwendungen verschiedenster Systeme zeigen einen anhaltenden Trend zur Unterstützung der konventionellen Bauwerksprüfungen über objektivierte Messungen. Der Schwerpunkt des Einsatzes liegt auf der Überwachung von Brücken als besonders sensible Ingenieurtragwerke. Erkenntnisse aus der langjährigen Aktivität der Autoren im Bereich der Bauwerksüberwachung sowie die Ergebnisse von Langzeitmessungen an einer Eisenbahnbrücke in Österreich werden präsentiert.
Modified Escherichia coli B (BL21), a superior producer of plasmid DNA compared with Escherichia coli K (DH5α)
Authors: Phue Je‐Nie , Lee Sang Jun , Trinh Loc , Shiloach Joseph
Published: May 2008

Plasmid DNA (pDNA) is an emerging experimental vaccine, produced in E. coli, initially targeted for viral diseases. Unlike traditional protein vaccines whose average dose is micrograms, the average dose of pDNA is on the scale of milligrams. Production yields are, therefore, important for the future development of this vaccine. The E. coli strains currently used for pDNA production, JM109 and DH5α, are both suitable for production of stable pDNA due to the deletion of recA and endA, however, these two E. coli K strains are sensitive to growth conditions such as high glucose concentration. On the other hand E. coli BL21 is less sensitive to growth conditions than E. coli JM109 or DH5α, this strain grows to higher densities and due to its active glyoxylate shunt and anaplerotic pathways is not sensitive to high glucose concentration. This strain is used for recombinant protein production but not for pDNA production because of its inability to produce stable pDNA. To adapt E. coli BL21 for stable pDNA production, the strain was mutated by deleting both recA and endA, and a proper growth and production strategy was developed. Production values, reaching 2 g/L were obtained using glucose as a carbon source. The produced plasmid, which was constructed for HIV clinical study, was found to have identical properties to the plasmid currently produced by E. coli DH5α. Biotechnol. Bioeng. 2008;101: 831–836. © 2008 Wiley Periodicals, Inc.
QCM‐D sensitivity to protein adsorption reversibility
Authors: Jordan Jacob L. , Fernandez Erik J.
Published: May 2008

Using a quartz crystal microbalance with dissipative monitoring (QCM‐D) we have determined the adsorption reversibility and viscoelastic properties of ribonuclease A adsorbed to hydrophobic self‐assembled monolayers. Consistent with previous work with proteins unfolding on hydrophobic surfaces, high protein solution concentrations, reduced adsorption times, and low ammonium sulfate concentrations lead to increased adsorption reversibility. Measured rigidity of the protein layers normalized for adsorbed protein amounts, a quantity we term specific dissipation, correlated with adsorption reversibility of ribonuclease A. These results suggest that specific dissipation may be correlated with changes in structure of adsorbed proteins. Biotechnol. Bioeng. 2008;101: 837–842. © 2008 Wiley Periodicals, Inc.