bluuebunny/crossref_metadata_2025_split huggingface dataset:
Well Design Differentiators for CO2 Sequestration in Depleted Reservoirs
Authors: Haigh M. J. 
Published: December 2009

Abstract
Reducing carbon emissions is a global problem which has become firmly established as a common objective. Sequestration of CO2 into underground oil and gas reservoirs on a large scale has the potential to make significant contribution to solving this problem. The process of carbon dioxide injection has been implemented in many different underground geological formations since the early 1970's as a means of enhancing oil recovery. CO2 injection purely for emissions reduction is however relatively new. This paper aims to identify key differentiators between conventional well design techniques and CO2 injection wells in depleted gas reservoirs. Technical focus is placed upon project management, completion well design and integrity assurance. The information is based on industry practices developed from published and unpublished CO2 sequestration projects and other data sources including input from contracting service companies.
The key objective is to support the concept and to demonstrate that CO2 sequestration into depleted reservoirs can be achieved effectively and safely from a well design perspective. The information provided in this paper will technically support feasibility studies, demonstrator schemes and contribute to the successful implementation of future CO2 sequestration projects globally. In summary this paper will review the unique operating environment of a CO2 injection well, identify critical differentiators and evaluate the impact on the well design.
Reservoir Architecture Characterization From Integration of Fluid Property Distributions With Other Logs
Authors: Dong Chengli , Chun Wei-Chun , Majkut Frederik , Mullins Oliver C. , Zuo Julian 
Published: December 2009

Abstract
Characterizing reservoir architecture and fluid property distributions at the early exploration and appraisal stage are critical for reservoir assessment, planning and management. Particularly for thinly laminated reservoirs, identification of hydrocarbon-bearing zones and determination of the flow unit sizes have profound impact on long term production predictions. In this paper, a case study is presented that integration of reservoir fluid property distribution with other logs leads to accurate reservoir understanding. In this method, downhole fluid analysis (DFA) is used to identify key production parameters of reservoir fluids in real time and at downhole conditions. DFA results are combined with other logs to develop a view of reservoir architecture especially pinpointing thin pay zones with low resistivity, which could be treated as wet by open-hole logs. Indeed, 19 DFA stations were performed in this particular well and represents a typical number of DFA stations per well in this field (another well in this field had significantly more DFA stations that established a world record). The results of the improved interpretation are confirmed by subsequent well test data. The case study indicates that the methodology of integrating DFA with other logs provides a powerful and cost effective approach for reservoir understanding and assessment at the exploration stage, which is invaluable for optimal reservoir management and development planning.
Forties: Creating a Long Range Development Plan for a Large, Mature, Complex North Sea Oil Field
Authors: Chesterman Alan , Vaughan Owen , Plahn Sheldon 
Published: December 2009

Abstract
Forties is the largest oil field in the United Kingdom Continental Shelf, with approximately 5 billion barrels of oil originally in place and 2.6 billion barrels of oil produced since start-up in 1975. After acquiring Forties and taking over as Operator in 2003, Apache rejuvenated the field with an active programme of infill drilling, workovers and facilities upgrades. Since 2003, 50 new targets have been drilled and projects to upgrade power generation, export pumps, and water injection systems have been completed. By 2008 the combined impact of these activities had increased production from 40,000 to a peak of 81,000 barrels per day and an annual average production in 2008 of 61,700 barrels per day
While these activities had been successful and profitable, Forties faced the ever increasing challenges common to mature field development – increasing well numbers and shortage of wells slots, increasing water production, variable drilling results, and ageing infrastructure beyond its original design life. Because of this, in 2008 Apache prepared a development plan for the long term future of the field. At this point it was important to take stock of the opportunities and challenges to confirm the forward direction and priorities.
Creating the plan required a multi-disciplinary effort spanning geology through to production operations. The target inventory and conditions of the facilities were reviewed and options to enhance the facilities and remove bottlenecks were identified. The interdependencies among disciplines and the implementation of the activities on the platforms were also key considerations, as were using the reservoir model and economic analysis to inform development decisions.
Preparing the development plan for a mature field, especially one as large and complex as Forties, brings its own unique set of challenges. These challenges and the approach used to address them are described here.
Hydrajetting Applications in Horizontal Completions to Improve Hydraulic Fracturing Stimulations and Improve ROI
Authors: McDaniel B. W. , Surjaatmadja Jim B. 
Published: December 2009

Abstract
This paper reviews applications of hydrajet perforating during the past 6+ years specifically as they apply to horizontal and highly deviated completions for both oil and gas reservoirs. Many benefits to hydraulic fracturing through hydrajetted perfs instead of shape charge perforations will often exist. Also, a key feature to more economic applications has been coupling this process with a method that includes multi-stage fracturing operations. This feature can shorten the completion time needed to achieve multistage frac treatments. During this decade, horizontal wells that need fracture stimulation are being drilled deeper and, especially, with longer lateral sections requiring larger numbers of fracturing stages. This has increasingly challenged the limits of conventional jetting systems and methods, while requiring higher pressure limits for the wellhead, treatment tubing, and pumping equipment.
Three primary methods for using hydrajet perforating have been part of the surge of horizontal well applications. Listed in the order of their emergence of significant application during the present decade, they are: hydrajet fracturing (HJF), hydrajet perforating, annulus path fracturing (HPAP), and standalone use of hydrajetted perforating (SHJP) followed by conventional wellbore stimulation and isolation applications.
Horizontal Marcellus Well Cementing in Appalachia
Authors: Gottschling John C. 
Published: December 2009

Abstract
It has become a high priority task of the drilling engineer to be closely involved in all aspects of the cement job design for a horizontal Marcellus well. Close cooperation with the cementing service company is required. It should be common place to use a simulator to facilitate job design and predict situations which could result in job failure. Comparing simulator runs to real time monitoring of job parameters can give indications of down-hole problems. Making on the spot decisions to change the job design can sometimes lessen or prevent the negative impact on the job performance which would have resulted if no changes were implemented.
This paper will review the accepted industry standards for hole conditioning, pipe centralization, pipe movement and slurry designs for HZ wellbores. A chart will be presented that includes all the tasks required for job design. Illustrations are provided to give operators realistic expectations of the engineering support they should be getting from their cementing service companies. Several slurry designs being used in Appalachia are presented and the required properties needed for successful horizontal well cementing in Appalachia. Results of these slurry designs will be presented as a relationship to the breakdown and treating pressures during the subsequent hydraulic fracturing treatments. The issue of the prevention of backside gas pressure will be discussed.
The Error Function and its Complement: A Comparison of Some Approximate Models
Authors: Lawal Kazeem A. 
Published: December 2009

Abstract
Applying the conservation laws to the transient transport problems of most processes, including diffusion, heat and momentum transfer, normally yield parabolic partial differential equations which solutions, for semi-infinite systems, usually include either the error function or the complementary error function. While tabulated values are available for real arguments of these functions, the need for look-up tables and interpolations makes them computationally intensive for implementation in computer programs and other applications. Although ‘simple’ models have been fitted to these values, it is imperative that such models preserve the key properties of these functions.
Combining the criteria of accuracy, differentiability, and integrability with mathematical consistency, this paper examines the approximate models of Kalkaja (2009), Winitzki (2008), van Halen (1989) and Greene (1989), premised on different assumptions and of varied forms and mathematical elegance.
In terms of accuracy, the van Halen (1989) model is the most reliable, successively trailed by Winitzki (2008), Kalkaja (2009), and Greene (1989) models. Despite being the most accurate, the van Halen (1989) model is the most complex and computationally expensive. Although they are all continuous and differentiable, obtaining their derivatives analytically, involves varying complexities, with van Halen (1989) most demanding and Greene (1989), the least intensive. With current knowledge, none of the models is amenable to analytic (direct) integration. Considering all performance indices, while the Winitzki model is the most consistent, van Halen approximation is the least consistent.
In conclusion, whereas the accuracies of these approximate models are satisfactory for most engineering applications, their robustness to mathematical (analytic) operations is not convincing. Although there is scope for improvement, it is recommended that greater efforts be directed at the development of theoretically rigorous models, which ironically, may not necessarily be more complex. Typical applications of this work include analysis of reservoirs under thermal or miscible floods.
Utility of Childhood Glucose Homeostasis Variables in Predicting Adult Diabetes and Related Cardiometabolic Risk Factors
Authors: Nguyen Quoc Manh , Srinivasan Sathanur R. , Xu Ji-Hua , Chen Wei , Kieltyka Lyn , Berenson Gerald S. 
Published: December 2009

OBJECTIVE
This study examines the usefulness of childhood glucose homeostasis variables (glucose, insulin, and insulin resistance index [homeostasis model assessment of insulin resistance {HOMA-IR}]) in predicting pre-diabetes and type 2 diabetes and related cardiometabolic risk factors in adulthood.

RESEARCH DESIGN AND METHODS
This retrospective cohort study consisted of normoglycemic (n = 1,058), pre-diabetic (n = 37), and type 2 diabetic (n = 25) adults aged 19–39 years who were followed on average for 17 years since childhood.

RESULTS
At least 50% of the individuals who ranked highest (top quintile) in childhood for glucose homeostasis variables maintained their high rank by being above the 60th percentile in adulthood. In a multivariate model, the best predictors of adulthood glucose homeostasis variables were the change in BMI Z score from childhood to adulthood and childhood BMI Z score, followed by the corresponding childhood levels of glucose, insulin, and HOMA-IR. Further, children in the top decile versus the rest for insulin and HOMA-IR were 2.85 and 2.55 times, respectively, more likely to develop pre-diabetes; children in the top decile versus the rest for glucose, insulin, and HOMA-IR were 3.28, 5.54, and 5.84 times, respectively, more likely to develop diabetes, independent of change in BMI Z score, baseline BMI Z score, and total-to-HDL cholesterol ratio. In addition, children with adverse levels (top quintile versus the rest) of glucose homeostasis variables displayed significantly higher prevalences of, among others, hyperglycemia, hypertriglyceridemia, and metabolic syndrome.

CONCLUSIONS
Adverse levels of glucose homeostasis variables in childhood not only persist into adulthood but also predict adult pre-diabetes and type 2 diabetes and relate to cardiometabolic risk factors.
On an integral transform by R. S. Phillips
Authors: Bjon Sten 
Published: December 2009

Abstract
The properties of a transformation $$
f \mapsto \tilde f_h
$$ by R.S. Phillips, which transforms an exponentially bounded C
0-semigroup of operators T(t) to a Yosida approximation depending on h, are studied. The set of exponentially bounded, continuous functions f: [0, ∞[→ E with values in a sequentially complete L
c-embedded space E is closed under the transformation. It is shown that $$
(\tilde f_h )\widetilde{_k } = \tilde f_{h + k}
$$ for certain complex h and k, and that $$
f(t) = \lim _{h \to 0^ + } \tilde f_h (t)
$$, where the limit is uniform in t on compact subsets of the positive real line. If f is Hölder-continuous at 0, then the limit is uniform on compact subsets of the non-negative real line. Inversion formulas for this transformation as well as for the Laplace transformation are derived. Transforms of certain semigroups of non-linear operators on a subset X of an L
c-embedded space are studied through the C
0-semigroups, which they define by duality on a space of functions on X.
Muscle Quality, Architecture, and Activation in Cachectic Patients with Rheumatoid Arthritis
Authors: MATSCHKE VERENA , MURPHY PETER , LEMMEY ANDREW B. , MADDISON PETER J. , THOM JEANETTE M. 
Published: December 2009

Objective. To explore muscle-specific force (force per physiological cross-sectional area, or PCSA) and muscle activation in cachectic patients with rheumatoid arthritis (RA).Methods. In 14 muscle-wasted patients with RA and age and sex matched healthy controls, vastus lateralis (VL) force and voluntary activation capacity were assessed during maximal isometric contractions with electromyography and superimposed electrical stimulations. VL PCSA was determined from ultrasound measures of fiber fascicle length (Lf), pennation angle, and volume, together with assessments of body composition by dual energy x-ray absorptiometry and objective physical function.Results. Although patients with RA had reduced physical function, lower muscle mass, and VL volume relative to controls, there were no differences in muscle-specific force and activation. PCSA, force, and pennation angle tended to be lower in RA, with no differences in Lf.Conclusion. Muscle-specific force and activation are not compromised and thus are unlikely to contribute to reduced function in cachectic patients with RA.
Comparison of the VISX WaveScan and NIDEK OPD-Scan Aberrometers
Authors: Kim David Sungmin , Narváez Julio , Krassin Jabin , Bahjri Khaled 
Published: December 2009

Purpose:
To compare measurements obtained with the VISX WaveScan and NIDEK OPD-Scan (ARK 10000).

Methods:

The VISX WaveScan is a wavefront aberrometer that uses Hartmann-Shack technology. The NIDEK OPD-Scan uses time-based retinoscopy (dynamic skiascopy). Measurements taken of 92 eyes from 51 patients using both aberrometers were retrieved and compared. Measurements included sphere, cylinder, axis, and Zernike coefficients of second to sixth radial order aberrations. The Zernike coefficients were normalized to a 6.0-mm pupil and used to calculate the root-mean-square (RMS) values of the radial orders, angular orders, total higher order aberrations, third order trefoil, third order coma, total spherical aberration, and total coma. Paired
t
tests were used to compare differences between measurements.

Results:
Although no significant difference was found between the NIDEK OPD-Scan and subjective manifest refraction in sphere and axis, the NIDEK OPD-Scan measured significantly higher cylinder. No significant difference was found between the VISX WaveScan and subjective manifest refraction. The NIDEK OPD-Scan had significantly lower total higher order, second radial order, third order coma, total spherical aberration, total coma, and second angular order RMS values. The VISX WaveScan had significantly lower cylinder, trefoil, third-angular order, and fifth-angular order RMS values.

Conclusions:

Specific and significant differences were noted between the measurements taken by the VISX WaveScan and NIDEK OPD-Scan wavefront aberrometers. [
J Refract Surg
. 2009;25:429–434.]
Precision of Orbscan II Assessment of Anterior Corneal Curvature and Asphericity
Authors: Douthwaite William Arthur , Parkinson Annette 
Published: December 2009

Purpose:
To determine the number of measurements required to produce a representative mean result for corneal apical radius and asphericity and to examine the repeatability of this mean result.

Methods:

The Bausch & Lomb Orbscan II corneal topographer was used to take 10 measurements of right eyes of 20 normal individuals. These were used to determine the number of measurements required to obtain a representative result. The apical radius and
p
-value were derived from the instrument software for the entire surface and also calculated from the raw data for a single meridian.

Results:

Both apical radius and asphericity stabilized as the number of responses contributing to the mean increased. Repeat measurement for the entire surface of a three-measurement mean result was ±0.090 mm for apical radius and ±0.151 for the
p
-value. The results for a single meridian, on repeat measurement, will lie within ±0.069 mm and ±0.051, respectively.

Conclusions:

Little improvement in stability or repeatability was observed after a three-measurement mean. The error and repeatability of the measurement appear to be better in this investigation when only a single meridian is analyzed. Thus, instrument software might be improved by providing analysis of apical radius and asphericity for a single, selectable meridian. [
J Refract Surg
. 2009;25:435–443.]
Cytohesin-1 Regulates the Arf6-Phospholipase D Signaling Axis in Human Neutrophils: Impact on Superoxide Anion Production and Secretion
Authors: El Azreq Mohammed-Amine , Garceau Valérie , Harbour Danielle , Pivot-Pajot Christophe , Bourgoin Sylvain G. 
Published: December 2009

Abstract
Polymorphonuclear neutrophil (PMN) stimulation with fMLP stimulates small G proteins such as ADP-ribosylation factors (Arfs) Arf1 and Arf6, leading to phospholipase D (PLD) activation and functions such as degranulation and the oxidative burst. However, the molecular links between fMLF receptors and PLD remain unclear. PMNs express cytohesin-1, an Arf-guanine exchange factor that activates Arfs, and its expression is strongly induced during the acquisition of the neutrophilic phenotype by neutrophil-like cells. The role of cytohesin-1 in the activation of the fMLF-Arf-PLD signaling axis, and the accomplishment of superoxide anion production, and degranulation was investigated in PMNs using the selective inhibitor of cytohesin, Sec 7 inhibitor H3 (secinH3). Cytohesin-1 inhibition with secinH3 leads to Arf6 but not Arf1 inhibition, demonstrating the specificity for Arf6, and fMLF-mediated activation of PLD and of the oxidative burst as well. We observed a decrease in fMLF-mediated protein secretion and expression of cell surface markers corresponding to primary (CD63/myeloperoxidase), secondary (CD66/lactoferrin), and tertiary (matrix metalloproteinase-9) granules in PMNs incubated with secinH3. Similarly, silencing cytohesin-1 or Arf6 in PLB-985 cells negatively affected fMLF-induced activation of PLD, superoxide production, and expression of granule markers on the cell surface. In contrast, stable overexpression of cytohesin-1 in PLB-985 cells enhanced fMLF-induced activation of Arf6, PLD, and NADPH oxidase. The results of this study provide evidence for an involvement of cytohesin-1 in the regulation of the functional responses of human PMNs and link these events, in part at least, to the activation of Arf6.
Independent Regulation of Chemokine Responsiveness and Cytolytic Function versus CD8+ T Cell Expansion by Dendritic Cells
Authors: Watchmaker Payal B. , Berk Erik , Muthuswamy Ravikumar , Mailliard Robbie B. , Urban Julie A. , Kirkwood John M. , Kalinski Pawel 
Published: December 2009

Abstract
The ability of cancer vaccines to induce tumor-specific CD8+ T cells in the circulation of cancer patients has been shown to poorly correlate with their clinical effectiveness. In this study, we report that although Ags presented by different types of mature dendritic cells (DCs) are similarly effective in inducing CD8+ T cell expansion, the acquisition of CTL function and peripheral-type chemokine receptors, CCR5 and CXCR3, requires Ag presentation by a select type of DCs. Both “standard” DCs (matured in the presence of PGE2) and type 1-polarized DCs (DC1s) (matured in the presence of IFNs and TLR ligands, which prevent DCs “exhaustion”) are similarly effective in inducing CD8+ T cell expansion and acquisition of CD45RO+IL-7R+IL-15R+ phenotype. However, granzyme B expression, acquisition of CTL activity, and peripheral tissue-type chemokine responsiveness are features exclusively exhibited by CD8+ T cells activated by DC1s. This advantage of DC1s was observed in polyclonally activated naive and memory CD8+ T cells and in blood-isolated melanoma-specific CTL precursors. Our data help to explain the dissociation between the ability of cancer vaccines to induce high numbers of tumor-specific CD8+ T cells in the blood of cancer patients and their ability to promote clinical responses, providing for new strategies of cancer immunotherapy.
AIDS Progression Is Associated with the Emergence of IL-17–Producing Cells Early After Simian Immunodeficiency Virus Infection
Authors: Campillo-Gimenez Laure , Cumont Marie-Christine , Fay Michèle , Kared Hassen , Monceaux Valérie , Diop Ousmane , Müller-Trutwin Michaela , Hurtrel Bruno , Lévy Yves , Zaunders John , Dy Michel , Leite-de-Moraes Maria C. , Elbim Carole , Estaquier Jérôme 
Published: December 2009

Abstract
IL-17 is a potent effector cytokine involved in inflammatory response and antimicrobial defense. We report that SIV infection of rhesus macaques (RMs) results in the emergence of IL-17–expressing cells during the acute phase. This subpopulation appears at day 14 postinfection concomitantly with an increase in TGF-β and IL-18 expression. This subset, which exhibits phenotypic markers of NK T cells (NKT), rather than Th17 CD4 cells, persists during the chronic phase and is higher in noncontrollers SIV-infected RMs compared with controllers SIV-infected RMs. In contrast, in the nonpathogenic model of SIVagm infection of African green monkeys, no change in the level of IL-17–expressing cells is observed in lymphoid organs. Consistent with the emergence of TGF-β and IL-18 during the acute phase in SIV-infected RMs, but not in SIV-infected African green monkeys, we demonstrate that in vitro TGF-β and IL-18 induce the differentiation and expansion of IL-17+NKT+. Altogether, these results demonstrate that IL-17–producing NKT are associated with the pathogenesis of SIV in RMs and suggest that TGF-β and IL-18 play a role in their development.