bluuebunny/crossref_metadata_2025_split huggingface dataset:
Next-Generation Managed Pressure Drilling System Enables HP/HT Horizontal Wells in the Haynesville Shale
Authors: Montilva Julio , Mota Jose , Poletzky Isabel C. , Sati Mohamed , Lovorn Randy , Grable Jeff 
Published: March 2012

Abstract
Managing pressure cycling on connections during drilling operations remains the greatest challenge for Managed Pressure Drilling (MPD) operators today. During conventional MPD operations, systems typically employ back pressure pumps to compensate for well back pressure across the well head. These conventional systems require a delicate control on connections between the driller managing rig pumps and the MPD operator managing back pressure pumps.
This paper describes implementation of a fully automated MPD system which incorporates a Rig Pump Diverter (RPD) that allows smooth transition from circulating to non-circulating down hole during connections while maintaining continuous rig pump circulation. The RPD system allows flow to be diverted from the stand pipe to the choke manifold, enabling accurate control of the bottomhole pressure (BHP) for controlled transition from drilling mode to connection mode. This paper will further describe the time savings and enhanced drill crew workflow associated with the use of the RPD system.
The paper describes the MPD implementation process, which included front-end engineering and design, HAZID/HAZOP (pre-job process of identification and management of potential hazards for operations), flow loop testing, in-house simulation, on-site drill crew training and will delineate the benefits of using the new system such as controlling annulus pressure during drilling operations. Additionally, results of field trials performed in High Pressure / High Temperature (HPHT) horizontal wells in the Haynesville Shale will be described.
We will show in the paper how this system operates on a small foot print while making the interaction between drilling crews and MPD crews highly effective. We will also demonstrate that the new MPD system provides better control managing pressure cycling, gas expansion and/or influx to the system, enabling effective drilling for better rate of penetration (ROP).
Drilling Contract Historical Development and Future Trends Post-Macondo: Reflections on a 35 Year Industry Career
Authors: Moomjian Cary A. 
Published: March 2012

Abstract
The author reflects upon a 35 year drilling industry career, over half of which was as General Counsel for two major drilling companies, to review the evolution of drilling contracts and discuss future contracting trends post-Macondo.
The historical review begins with the advent of the oil and gas industry and considers developments that led to issuance of the first (IADC predecessor) AAODC standard drilling contract in 1952. The paper then traces the evolution of drilling contracts as they became more complex and sophisticated while the industry extended into the offshore and international arenas.
Major events that impacted contracting, such as development of various standard contracts, anti-indemnity statutes and other legislation, judicial decisions, the "Drilling in the '90s" and other strategic initiatives, are considered. Incentive, variable rate and multi-party drilling contracts are reviewed. The paper also discusses contractual provisions that were implemented to address operational and technical innovations such as horizontal drilling, extension into deepwater and dual activity simultaneous operations capability.
The dichotomy between U.S. land operations (which primarily utilize IADC model contract forms) and offshore and international operations (which generally are based on operator standard contracts) is considered along with the impact of market forces upon drilling contract terms. The difficulties encountered when contracting with national oil companies that insist upon adherence to their standard forms are discussed. Controversial issues, such as the enforceability of indemnities in the event of gross negligence, are reviewed. The paper also discusses the impact of Macondo upon drilling contract terms.
With this background, anticipated future contracting trends in a post-Macondo world are considered.
Understanding Shale Heterogeneity - Key to Minimizing Drilling Problems in Horn River Basin
Authors: Khan Safdar , Ansari Sajjad , Han Hongue , Khosravi Nader 
Published: March 2012

Abstract
More than 70% of nonproductive time (NPT) and increases in drilling cost are related to wellbore instabilities. Shale formations are the primary sources (90%) for wellbore instabilities. Numerous wellbore instability problems have been reported in the Horn River basin (HRB), the largest shalegas play in Canada. As a consequence of the depositional environment, shale formations have laminated structure that results in anisotropic mechanical properties and horizontal stresses. Failure to consider this characteristic of shale can have severe consequences on drilling. Traditional isotropic stress calculation approaches typically used in wellbore stability analysis do not consider 3D azimuthal anisotropy present in shales. Ignoring anisotropy generally results in underestimation of stresses, which can lead to incorrect safe trajectory or mud-weights predictions.
In this paper, drilling problems experienced in 15 wells in two different areas of the HRB were examined. Some of these wells had severe wellbore instabilitis due to high pore pressure, mud losses or lost circulation, tight hole/stuck pipe/pack off, or combination of these events. Three borehole assemblies (BHA) were lost in these wells which required side tracking. Most of these problems were experienced in Fort Simpson and upper Muskwa formations. An in-depth postmortem analysis of these wells indicated that shale heterogeneity was not properly characterized (anisotropic horizontal stresses were not considered in the prespud analysis which resulted in incorrect mud-weight predictions and trajectory calculations.
Negative Special Items and Future Earnings: Expense Transfer or Real Improvements?
Authors: Cready William M. , Lopez Thomas J. , Sisneros Craig A. 
Published: March 2012

ABSTRACT
Burgstahler et al. (2002) investigate the implications of special items for future earnings and report that firms use negative special items to accelerate the recognition of future expenses into the current period. That is, negative special items serve as an “inter-period transfer” device. We extend their analysis and find that earnings increase in post-special item quarters beyond the four quarters considered in Burgstahler et al. (2002). In particular, we find that future earnings increase over the subsequent 16 quarters by more than 130 percent of the reported negative special item. The earnings increases are greater for restructuring charges than for asset write-downs or goodwill impairment charges. Such patterns suggest that negative special items also signal real future performance improvements (i.e., performance improvement hypothesis) in addition to inter-period expense transfer (i.e., inter-period transfer hypothesis). Moreover, the real improvement effect appears to be driven by restructuring charges, the most prevalent type of special item.
Analysis of the role of the integrin signaling pathway in hepatocytes during rat liver regeneration
Authors: Xu Cunshuan , Yang Yanjie , Yang Junying , Chen Xiaoguang , Wang Gaiping 
Published: March 2012

AbstractTo explore the role of the integrin signaling pathway in hepatocytes during rat liver regeneration, the integrin signaling pathway-related gene expression profile in hepatocytes of regenerative liver was detected using Rat Genome 230 2.0 array. The chip data showed that 265 genes of the integrin signaling pathway were included by Rat Genome 230 2.0 array and 132 genes showed significant expression changes in hepatocytes of regenerative liver. The numbers of up-, down- and up/down-regulated genes were 110, 15 and 7 respectively. In addition, bioinformatics and systems biology methods were used to analyze the role of the integrin signaling pathway in hepatocytes. The analysis of gene synergy value indicated that paths 1, 8, 12, and 15 promoted hepatocyte proliferation at the priming phase of liver regeneration; paths 1, 3, 8, and 12–15 enhanced hepatocyte proliferation at the progressing phase; paths 11 and 14 promoted hepatocyte proliferation, while paths 12 and 13 reduced hepatocyte proliferation at the terminal phase. Additionally, the other 8 paths (2, 4, 5–7, 9–10, and 16) were not found to be related to liver regeneration. In conclusion, 132 genes and 8 cascades of the integrin signaling pathway participated in regulating hepatocyte proliferation during rat liver regeneration.
Deficiency in TR4 nuclear receptor abrogates Gadd45a expression and increases cytotoxicity induced by ionizing radiation
Authors: Yan Shian-Jang , Lee Yi-Fen , Ting Huei-Ju , Liu Ning-Chun , Liu Su , Lin Shin-Jen , Yeh Shauh-Der , Li Gonghui , Chang Chawnshang 
Published: March 2012

AbstractThe testicular receptor 4 (TR4) is a member of the nuclear receptor superfamily that controls various biological activities. A protective role of TR4 against oxidative stress has recently been discovered. We here examined the protective role of TR4 against ionizing radiation (IR) and found that small hairpin RNA mediated TR4 knockdown cells were highly sensitive to IR-induced cell death. IR exposure increased the expression of TR4 in scramble control small hairpin RNA expressing cells but not in TR4 knockdown cells. Examination of IR-responsive molecules found that the expression of Gadd45a, the growth arrest and DNA damage response gene, was dramatically decreased in Tr4 deficient (TR4KO) mice tissues and could not respond to IR stimulation in TR4KO mouse embryonic fibroblast cells. This TR4 regulation of GADD45A was at the transcriptional level. Promoter analysis identified four potential TR4 response elements located in intron 3 and exon 4 of the GADD45A gene. Reporter and chromatin immunoprecipitation (ChIP) assays provided evidence indicating that TR4 regulated the GADD45A expression through TR4 response elements located in intron 3 of the GADD45A gene. Together, we find that TR4 is essential in protecting cells from IR stress. Upon IR challenges, TR4 expression is increased, thereafter inducing GADD45A through transcriptional regulation. As GADD45A is directly involved in the DNA repair pathway, this suggests that TR4 senses genotoxic stress and up-regulates GADD45A expression to protect cells from IR-induced genotoxicity.
Quantification of Pupil Parameters in Diseased and Normal Eyes With Near Infrared Iris Transillumination Imaging
Authors: Roberts Daniel K. , Yang Yongyi , Lukic Ana S. , Wilensky Jacob T. , Wernick Miles N. 
Published: March 2012

BACKGROUND AND OBJECTIVE:
To investigate near infrared iris transillumination (NIRit) imaging as a new method to quantify pupil shape, size, and position because the imaging modality can uniquely provide simultaneous information regarding iris structural details that influence pupil characteristics and because exploration of related techniques could promote discovery helpful to clinical research and care.

PATIENTS AND METHODS:
Digital NIRit images of normal and diseased eyes were used along with computer-assisted techniques to quantify four primary pupil parameters, including pupil roundness (PR), pupil ovalness (PO), pupil size (PS), and pupil eccentricity (PE). A combined measure of PR and PO was also developed (the pupil circularity index [PCI]). Repeatability of the measures was studied and example analyses were performed.

RESULTS:

Pupil measures could be calculated for right eyes of 307 subjects (164 normal, 143 other), with fewer than 0.5% exclusions due to image quality. Repeatability study did not show significant bias (
P
< .05) for any of the four primary measures. Example analyses could show age-associated differences in pupil shape (⩾ 50 year olds had less regular pupils than < 50 year olds: median PCI = 0.009 vs 0.006;
P
< .01) and that a group of pigment dispersion syndrome subjects (n = 27) had less regular pupils than a group of matched controls (PO = 0.9966 vs 0.9990;
P
< .05).

CONCLUSION:
Digital NIRit imaging can provide novel, reliable, and informative methods to quantify pupil characteristics while providing simultaneous information about iris structure that may influence these parameters.
Cutting Edge: Dendritic Epidermal γδ T Cell Ligands Are Rapidly and Locally Expressed by Keratinocytes following Cutaneous Wounding
Authors: Komori H. Kiyomi , Witherden Deborah A. , Kelly Ryan , Sendaydiego Kevin , Jameson Julie M. , Teyton Luc , Havran Wendy L. 
Published: March 2012

Abstract
TCR-specific activation is pivotal to dendritic epidermal T cell (DETC) function during cutaneous wound repair. However, DETC TCR ligands are uncharacterized, and little is known about their expression patterns and kinetics. Using soluble DETC TCR tetramers, we demonstrate that DETC TCR ligands are not constitutively expressed in healthy tissue but are rapidly upregulated following wounding on keratinocytes bordering wound edges. Ligand expression is tightly regulated, with downmodulation following DETC activation. Early inhibition of TCR–ligand interactions using DETC TCR tetramers delays wound repair in vivo, highlighting DETC as rapid responders to injury. To our knowledge, this is the first visualization of DETC TCR ligand expression, which provides novel information about how ligand expression impacts early stages of DETC activation and wound repair.
Extracellular Superoxide Dismutase Inhibits Innate Immune Responses and Clearance of an Intracellular Bacterial Infection
Authors: Break Timothy J. , Jun Sujung , Indramohan Mohanalaxmi , Carr Karen D. , Sieve Amy N. , Dory Ladislav , Berg Rance E. 
Published: March 2012

Abstract
Reactive oxygen species and reactive nitrogen species play important roles during immune responses to bacterial pathogens. Extracellular superoxide dismutase (ecSOD) regulates extracellular concentrations of reactive oxygen species and reactive nitrogen species and contributes to tissue protection during inflammatory insults. The participation of ecSOD in immune responses seems therefore intuitive, yet is poorly understood. In the current study, we used mice with varying levels of ecSOD activity to investigate the involvement of this enzyme in immune responses against Listeria monocytogenes. Surprisingly, our data demonstrate that despite enhanced neutrophil recruitment to the liver, ecSOD activity negatively affected host survival and bacterial clearance. Increased ecSOD activity was accompanied by decreased colocalization of neutrophils with bacteria, as well as increased neutrophil apoptosis, which reduced overall and neutrophil-specific TNF-α production. Liver leukocytes from mice lacking ecSOD produced equivalent NO· compared with liver leukocytes from mice expressing ecSOD. However, during infection, there were higher levels of peroxynitrite (NO3·−) in livers from mice lacking ecSOD compared with livers from mice expressing ecSOD. Neutrophil depletion studies revealed that high levels of ecSOD activity resulted in neutrophils with limited protective capacity, whereas neutrophils from mice lacking ecSOD provided superior protection compared with neutrophils from wild-type mice. Taken together, our data demonstrate that ecSOD activity reduces innate immune responses during bacterial infection and provides a potential target for therapeutic intervention.
Das Komplementsystem
Authors: Frauenknecht V. , Schroeder V. 
Published: March 2012

SummaryAtherosclerotic diseases such as coronary artery disease and ischaemic stroke are caused by chronic inflammation in arterial vessel walls. The complement system is part of the innate immune system. It is involved in many processes contributing to onset and development of atherosclerotic plaques up to the final stage of acute thrombotic events. This is due to its prominent role in inflammatory processes. In addition, there is increasing evidence that interactions between complement and coagulation provide a link between inflammation and thrombosis. On the other hand, the complement system also has an atheroprotective function through the clearance of apoptotic material.The knowledge of these complex mechanisms will become increasingly important, also for clinicians, since it may lead to novel therapeutic and diagnostic options. Therapies targeting the complement system have the potential to reduce tissue damage caused by acute ischaemic events. Whether early anti-inflammatory and anti-complement therapy may be able to prevent atherosclerosis, remains a hot topic for research.
Introduction to Surfactant Self‐Assembly
Authors: Romsted Laurence S. 
Published: February 2012

AbstractCurrent models and concepts are introduced and used to characterize the physical properties of homogeneous, small molecule, surfactant solutions such as the critical micelle concentration (cmc), aggregation number, degree of ionization of ionic aggregates and the interactions that determine the size and shape of aggregates, various mesophases such as spherical and rodlike micelles, lamellar, vesicular, bicontinuous, and reverse micelles, and the chemical reactivity in surfactant solutions. Surfactant aggregation is a spontaneous process and a delicate balance of forces governs the size and shapes of the structures at equilibrium. Aggregation is driven by the hydrophobic effect, the minimization of surfactant tail‐water contact by transfer of the tail of the surfactant unimer from water to the aggregate core with the concomitant release of water of hydration, and an increase in the entropy of the system. Balance is provided by a combination of electrostatic, ion‐specific, and hydration interactions in the interfacial region of the aggregates. Two models are generally used to interpret surfactant aggregation and solution properties, the more generally applied pseudophase model and the mass action model. For example, pseudophase models provide a comprehensive interpretation of micellar effects on chemical reactivity. A major unsolved problem is developing a general interpretation of ion‐specific effects, as exemplified by the Hofmeister series on surfactant aggregate properties. The ion‐pair hydration model represents one potential solution.
Ion‐Selective Electrodes With Ionophore‐Doped Sensing Membranes
Authors: Bühlmann Philippe , Chen Li D. 
Published: February 2012

AbstractRecent work in the field of ionophore‐based ion‐selective electrodes (ISEs) has greatly improved our understanding of the thermodynamics and kinetics that describe the response and selectivity of these sensors. These efforts resulted in the lowering of detection limits from micro‐ to subpicomolar concentrations, improvements of selectivities by many orders of magnitude, and major advancements in biocompatibility and long‐term stabilities. This chapter summarizes the current state of the art for an audience that is new to the field, introducing the basic concepts of ISE theory that replaced in recent years the empirical approach of the early ISE history. It illustrates, with specific examples, the design principles of host‐guest chemistry that have been used to develop ionophores for ISEs, and describes with a minimum of equations the recently developed sophisticated concepts for the efficient use of these ionophores in ISEs. Importantly, this chapter shows not only how ionophores are used in modern potentiometry to develop new ISEs but also illustrates how ionophore‐based potentiometry can support host‐guest chemistry by providing tools to determine thermodynamic properties of ionophores, such as stoichiometries and stabilities of their complexes, using only a minimum amount of ionophore.
Balanced complex chromosome rearrangements: Reproductive aspects. A review
Authors: Madan Kamlesh 
Published: March 2012

AbstractThis review examines the reproductive consequences for carriers of a balanced complex chromosome rearrangement (CCR). It is based on an analysis of CCRs in 103 adults referred for reproductive problems, including male infertility. The main focus is on reproductive risks based on data from 84 CCRs. Carriers of balanced CCRs have a high risk of an abortion and/or a chromosomally unbalanced child. I have identified roughly four different types of CCRs (I–IV); most (44%) belong to Type I with a simple 3‐way or 4‐way exchange of segments and risk factors similar to those for reciprocal translocations. There were only three CCRs (4%) of type II, which involve an inversion. Type III CCRs (21%) involve one or more insertions with ∼35% risk of a child with a duplication or a deletion of the inserted segment. Type IV CCRs (31%) involve a “middle segment” in a derivative chromosome with segments from at least three chromosomes. In ∼35% of these CCRs, recombination occurs in this segment, which can produce imbalance but in many cases it changes a CCR into a simpler balanced rearrangement in the next generation. Balanced CCRs, which have been often considered together in one group, can now be split into four types, each with a risk of a different type of imbalance. This analysis provides a better understanding of the reproductive consequences for carriers of balanced CCRs and should be useful in prenatal diagnosis and genetic counseling. © 2012 Wiley Periodicals, Inc.
A second case of contractures, webbed neck, micrognathia, hypoplastic nipples, and distinctive facial features: Confirmation of the Dinno syndrome
Authors: Wall Nerilee , McGaughran Julie 
Published: March 2012

AbstractWe report on a child with micrognathia, a short, webbed neck, joint contractures, hypoplastic nipples, and a number of other anomalies. There are striking similarities to a patient reported by [Dinno and Weisskopf (1976); Synd Ident, 4:10–12], and we postulate that this child represents the second patient with this condition. © 2012 Wiley Periodicals, Inc.
Identification of 2 novel ANTXR2 mutations in patients with hyaline fibromatosis syndrome and proposal of a modified grading system
Authors: Denadai Rafael , Raposo‐Amaral Cassio E. , Bertola Débora , Kim Chong , Alonso Nivaldo , Hart Thomas , Han Sangwoo , Stelini Rafael F. , Buzzo Celso L. , Raposo‐Amaral Cesar A. , Hart P. Suzanne 
Published: March 2012

AbstractJuvenile hyaline fibromatosis (JHF) and infantile systemic hyalinosis (ISH) are rare, autosomal recessive disorders of the connective tissue caused by mutations in the gene encoding the anthrax toxin receptor 2 protein (ANTXR2) located on chromosome 4q21. Characteristically, these conditions present with overlapping clinical features, such as nodules and/or pearly papules, gingival hyperplasia, flexion contractures of the joints, and osteolytic bone defects. The present report describes a pair of sibs and three other JHF/ISH patients whose diagnoses were based on typical clinical manifestations and confirmed by histopathologic analyses and/or molecular analysis. A comparison of ISH and JHF, additional thoughts about new terminology (hyaline fibromatosis syndrome) and a modified grading system are also included. © 2012 Wiley Periodicals, Inc.