bluuebunny/crossref_metadata_2025 huggingface dataset:
Sentinel Lymph Node Biopsy in the Management of Vulvar Carcinoma, Cervical Cancer, and Endometrial Cancer
Authors: Zivanovic Oliver , Khoury-Collado Fady , Abu-Rustum Nadeem R. , Gemignani Mary L.
Published: July 2009

The treatment of gynecologic malignancies can include surgery, systemic therapy, and radiation. Depending on the primary site of disease and the extent of the disease, these treatment strategies are applied alone or in combination.

Trends over the past few decades have concentrated on performing more comprehensive staging procedures for a large percentage of patients with gynecologic malignancies. The surgical techniques available for comprehensive staging have facilitated a greater understanding of stage and prognosis overall, and better tailoring of postsurgical treatment.

One such technique is regional lymphadenectomy. Although the role of regional lymphadenectomy as a therapeutic procedure in some gynecologic cancers is debated and challenged (regional lymphadenectomy and multimodality therapy increases adverse side effects and long-term sequelae without proven survival benefit), there is no controversy regarding the staging and prognostic benefit of the evaluation of regional lymph nodes. The sentinel lymph node (SLN) concept was successfully introduced in melanoma. It has since become the standard of care in breast cancer and has had a significant impact on postoperative morbidity for a large percentage of breast cancer patients. Interest in using SLN techniques in gynecologic cancers was thus a natural progression. In light of the growing body of evidence in the literature opposing the therapeutic benefit of systematic lymphadenectomy, the SLN concept will continue to play an important role in the treatment of gynecologic malignancies. This technique can provide accurate staging information in some gynecologic cancers. Increased use of this technique could potentially impact the quality of life of gynecologic cancer survivors while still providing important staging information without compromising oncologic safety.

In this review, we examine the body of literature related to gynecologic cancer malignancies and SLN biopsy.
The mineralocorticoid receptor and its coregulators
Authors: Yang Jun , Young Morag J
Published: July 2009

The mineralocorticoid receptor (MR) is a member of the nuclear receptor superfamily and is essential for controlling sodium transport in epithelial tissues such as the kidney and colon. Moreover, it is also present in other non-epithelial tissues and is capable of activation by both mineralocorticoids and glucocorticoids. A challenge in understanding transcriptional regulation by the MR and other nuclear receptors is to determine how tissue- and ligand-specificity is achieved. Over the past decade, it has become clear that a heterogeneous group of non-receptor proteins termed as coregulators are required to either enhance or repress nuclear receptor-mediated transactivation of target genes. A subset of these coregulators may be expected to confer specificity to MR-mediated responses by virtue of their variable tissue expression and selectivity for different ligands. Specific coregulator–MR interactions may be a suitable target in the rational design of tissue-specific MR modulators as has been described for other steroid receptors. However, the number of coregulators identified to date for the MR is very limited compared with other nuclear receptors. Understanding the full complement of MR coregulators is essential for unraveling the complexity of MR signaling pathways and will facilitate the development of selective MR modulators.
One process for pancreatic β-cell coalescence into islets involves an epithelial–mesenchymal transition
Authors: Cole Lori , Anderson Miranda , Antin Parker B , Limesand Sean W
Published: July 2009

Islet replacement is a promising therapy for treating diabetes mellitus, but the supply of donor tissue for transplantation is limited. To overcome this limitation, endocrine tissue can be expanded, but this requires an understanding of normal developmental processes that regulate islet formation. In this study, we compare pancreas development in sheep and human, and provide evidence that an epithelial–mesenchymal transition (EMT) is involved in β-cell differentiation and islet formation. Transcription factors know to regulate pancreas formation, pancreatic duodenal homeobox factor 1, neurogenin 3, NKX2-2, and NKX6-1, which were expressed in the appropriate spatial and temporal pattern to coordinate pancreatic bud outgrowth and direct endocrine cell specification in sheep. Immunofluorescence staining of the developing pancreas was used to co-localize insulin and epithelial proteins (cytokeratin, E-cadherin, and β-catenin) or insulin and a mesenchymal protein (vimentin). In sheep, individual β-cells become insulin-positive in the progenitor epithelium, then lose epithelial characteristics, and migrate out of the epithelial layer to form islets. As β-cells exit the epithelial progenitor cell layer, they acquire mesenchymal characteristics, shown by their acquisition of vimentin. In situ hybridization expression analysis of the SNAIL family members of transcriptional repressors (SNAIL1, -2, and -3; listed as SNAI1, -2, -3 in the HUGO Database) showed that each of the SNAIL genes was expressed in the ductal epithelium during development, and SNAIL-1 and -2 were co-expressed with insulin. Our findings provide strong evidence that the movement of β-cells from the pancreatic ductal epithelium involves an EMT.
NOD2 receptors in adenopituitary folliculostellate cells: expression and function
Authors: Correa-de-Santana Eliane , Fröhlich Bianca , Labeur Marta , Páez-Pereda Marcelo , Theodoropoulou Marily , Monteserin Jose Luis , Renner Ulrich , Stalla Günter K
Published: July 2009

Folliculostellate cells (FS cells) are non-endocrine cells from the pituitary gland that respond to bacterial endotoxins by producing cytokines. In immune cells, an important component of bacterial recognition are the toll-like receptors (TLRs). Previously, we showed that FS cells express TLR4. The TLR4 ligand lipopolysaccharide (LPS) stimulates interleukin-6 (IL6) production through nuclear factor κB (NFKB) induction. Binding of IL6 to gp130 receptor activates signal transducer and activator of transcription 3 (STAT3), an important mediator of inflammatory response. Another family involved in innate immune response following bacterial infection is the nucleotide-binding oligomerisation domain (NOD) intracellular receptor family. Herein, we describe for the first time the expression and function of NOD receptors in human pituitary and FS TtT/GF cell line. The NOD2 agonist muramyl dipeptide (MDP) increased Nfκb1-transcriptional activity, -protein expression and IL6 secretion in TtT/GF cells. Furthermore, these effects were potentiated by the combination of MDP and LPS. Silencing NOD2 abolished the action of LPS on NFKB transcriptional activity and IL6 production, indicating that, in TtT/GF cells, TLR4 transduces its signal through NOD2 receptor. We show here that in TtT/GF cells, Nod2 overexpression or stimulation by MDP increased STAT3 transcriptional activity. Furthermore, silencing STAT3 inhibited basal, LPS and MDP stimulated NFKB protein expression and overexpression of protein inhibitor of activated STAT3 (Pias3) markedly decreased basal NFKB activity. These data suggest that in TtT/GF cells, STAT3 acting upstream to NFKB mediates NOD2 receptor signalling pathway. In conclusion, the present study demonstrates that NOD molecules play a modulatory role in the pituitary by regulating the function and activation of FS cells in response to bacterial components.
Pharmaceutical industry effluent diluted 1:500 affects global gene expression, cytochrome P450 1A activity, and plasma phosphate in fish
Authors: Gunnarsson Lina , Kristiansson Erik , Rutgersson Carolin , Sturve Joachim , Fick Jerker , Förlin Lars , Larsson D. G. Joakim
Published: July 2009

Patancheru, near Hyderabad, India, is a major production site for the global bulk drug market. Approximately 90 manufacturers send their wastewater to a common treatment plant in Patancheru. Extraordinary high levels of a wide range of pharmaceuticals have recently been demonstrated in the treated effluent. As little as 0.2% of this effluent can strongly reduce the growth rate of tadpoles, but the underlying mechanisms of toxicity are not known. To begin addressing how the effluent affects aquatic vertebrates, rainbow trout (Oncorhynchus mykiss) were exposed to 0.2% effluent for 5 d. Several physiological endpoints, together with effects on global hepatic gene expression patterns, were analyzed. The exposed fish showed both an induction of hepatic cytochrome P450 1A (CYP1A) gene expression, as well as enzyme activity. Clinical blood chemistry analyses revealed an increase in plasma phosphate levels, which in humans indicates impaired kidney function. Several oxidative stress-related genes were induced in the livers; however, no significant changes in antioxidant enzyme activities or in the hepatic glutathione levels were found. Furthermore, estrogen-regulated genes were slightly up-regulated following exposure, and moderate levels of estriol were detected in the effluent. The present study identifies changes in gene expression triggered by exposure to a high dilution of the effluent, supporting the hypothesis that these fish are responding to chemical exposure. The pattern of regulated genes may contribute to the identification of mechanisms of sublethal toxicity, as well as illuminate possible causative agents.
Improving Service Delivery in a County Health Department WIC Clinic: An Application of Statistical Process Control Techniques
Authors: Boe Debra Thingstad , Riley William , Parsons Helen
Published: July 2009

Local public health agencies are challenged to continually improve service delivery, yet they frequently operate with constrained resources. Quality improvement methods and techniques such as statistical process control are commonly used in other industries, and they have recently been proposed as a means of improving service delivery and performance in public health settings. We analyzed a quality improvement project undertaken at a local Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) clinic to reduce waiting times and improve client satisfaction with a walk-in nutrition education service. We used statistical process control techniques to evaluate initial process performance, implement an intervention, and assess process improvements. We found that implementation of these techniques significantly reduced waiting time and improved clients' satisfaction with the WIC service.
The Influence of the VERB Campaign on Children's Physical Activity in 2002 to 2006
Authors: Huhman Marian E. , Potter Lance D. , Nolin Mary Jo , Piesse Andrea , Judkins David R. , Banspach Stephen W. , Wong Faye L.
Published: July 2009

Objectives. We evaluated physical activity outcomes for children exposed to VERB, a campaign to encourage physical activity in children, across campaign years 2002 to 2006.

Methods. We examined the associations between exposure to VERB and (1) physical activity sessions (free time and organized) and (2) psychosocial outcomes (outcome expectations, self-efficacy, and social influences) for 3 nationally representative cohorts of children. Outcomes among adolescents aged 13 to 17 years (cohort 1, baseline) and children aged 9 to 13 years from cohorts 2 and 3 were analyzed for dose–response effects. Propensity scoring was used to control for confounding influences.

Results. Awareness of VERB remained high across campaign years. In 2006, reports of children aged 10 to 13 years being active on the day before the survey increased significantly as exposure to the campaign increased. Psychosocial outcomes showed dose–response associations. Effects lessened as children aged out of the campaign target age range (cohort 1, baseline), but dose–response associations persisted in 2006 for outcome expectations and free-time physical activity.

Conclusions. VERB positively influenced children's physical activity outcomes. Campaign effects persisted as children grew into their adolescent years.
Carbon Monoxide Epidemic Among Immigrant Populations: King County, Washington, 2006
Authors: Gulati Reena K. , Kwan-Gett Tao , Hampson Neil B. , Baer Atar , Shusterman Dennis , Shandro Jamie R. , Duchin Jeffrey S.
Published: July 2009

Objectives. We investigated an outbreak of carbon monoxide (CO) poisoning after a power outage to determine its extent, identify risk factors, and develop prevention measures.

Methods. We reviewed medical records and medical examiner reports of patients with CO poisoning or related symptoms during December 15 to 24, 2006. We grouped patients into households exposed concurrently to a single source of CO.

Results. Among 259 patients with CO poisoning, 204 cases were laboratory confirmed, 37 were probable, 10 were suspected, and 8 were fatal. Of 86 households studied, 58% (n = 50) were immigrant households from Africa (n = 21), Asia (n = 15), Latin America (n = 10), and the Middle East (n = 4); 34% (n = 29) were US-born households. One percent of households was European (n = 1), and the origin for 7% (n = 6) was unknown. Charcoal was the most common fuel source used among immigrant households (82%), whereas liquid fuel was predominant among US-born households (34%).

Conclusions. Educational campaigns to prevent CO poisoning should consider immigrants’ cultural practices and languages and specifically warn against burning charcoal indoors and incorrect ventilation of gasoline- or propane-powered electric generators.
Explaining the Decrease in Coronary Heart Disease Mortality in Italy Between 1980 and 2000
Authors: Palmieri Luigi , Bennett Kathleen , Giampaoli Simona , Capewell Simon
Published: July 2009

Objectives. We examined the extent to which the decrease in coronary heart disease (CHD) mortality rates in Italy could be explained by changes in cardiovascular risk factors versus the use of medical and surgical treatments.

Methods. We used a validated model to combine data on changes in risk factors and uptake and effectiveness of cardiac treatments among adult men and women in Italy between 1980 and 2000. Data sources included results of published trials, meta-analyses, official statistics, longitudinal studies, and national surveys. The difference between observed and expected CHD deaths in 2000 was partitioned among treatments and risk factors.

Results. From 1980 to 2000, the age-adjusted CHD mortality rate in Italy fell among persons aged 25 to 84 years, resulting in 42 930 fewer CHD deaths in 2000. Approximately 40% of this decrease was attributed to treatments and 55% to changes in risk factors.

Conclusions. Over half of the CHD mortality fall in Italy between 1980 and 2000 was attributable to reductions in major risk factors, mainly cholesterol and blood pressure, and less than half to evidence-based medical therapies. These results are becoming increasingly important, both for understanding past trends and for planning future prevention and treatment strategies.
Estimated Autism Risk and Older Reproductive Age
Authors: King Marissa D. , Fountain Christine , Dakhlallah Diana , Bearman Peter S.
Published: July 2009

Objectives. We sought to estimate the risk for autism associated with maternal and paternal age across successive birth cohorts.

Methods. We linked birth records and autism diagnostic records from the California Department of Developmental Services for children born in California between 1992 and 2000 to calculate the risk associated with maternal and paternal age for each birth cohort as well as for the pooled data.

Results. The categorical risks associated with maternal age over 40 years ranged from a high of 1.84 (95% confidence interval [CI] = 1.37, 2.47) to a low of 1.27 (95% CI = 0.95, 1.69). The risk associated with paternal age ranged from 1.29 (95% CI = 1.03, 1.6) to 1.71 (95% CI = 1.41, 2.08).

Conclusions. Pooling data across multiple birth cohorts inflates the risk associated with paternal age. Analyses that do not suffer from problems produced by pooling across birth cohorts demonstrated that advanced maternal age, rather than paternal age, may pose greater risk. Future research examining parental age as a risk factor must be careful to avoid the paradoxes that can arise from pooling data, particularly during periods of social demographic change.
Public Health, the APHA, and Urban Renewal
Authors: Lopez Russ P.
Published: July 2009

Joint efforts by fields of public health in the last decade have advocated use of the built environment to protect health. Past involvement by public health advocates in urban policy, however, has had mixed results. Although public health has significantly contributed to health improvements, its participation in urban renewal activities was problematic. Health advocates and the American Public Health Association produced guidelines that were widely used to declare inner-city areas blighted and provided a scientific justification for demolishing neighborhoods and displacing mostly poor and minority people. Furthermore, health departments failed to uphold their legal responsibility to ensure that relocated families received safe, affordable housing alternatives. These failures have important implications for future health-related work on the built environment and other core public health activities.
Understanding Bureaucracy in Health Science Ethics: Toward a Better Institutional Review Board
Authors: Bozeman Barry , Slade Catherine , Hirsch Paul
Published: July 2009

Research involving human participants continues to grow dramatically, fueled by advances in medical technology, globalization of research, and financial and professional incentives. This creates increasing opportunities for ethical errors with devastating effects. The typical professional and policy response to calamities involving human participants in research is to layer on more ethical guidelines or strictures.

We used a recent case—the Johns Hopkins University/Kennedy Kreiger Institute Lead Paint Study—to examine lessons learned since the Tuskegee Syphilis Study about the role of institutionalized science ethics in the protection of human participants in research. We address the role of the institutional review board as the focal point for policy attention.
“Everywhere the Soldier Will Be”: Wartime Tobacco Promotion in the US Military
Authors: Smith Elizabeth A. , Malone Ruth E.
Published: July 2009

Deployment of young Americans in military engagements places them at increased risk for not only war hazards but also tobacco addiction and disease. Tobacco use diminishes troop health and readiness, and increases medical and training costs.

Military tobacco control efforts began in 1986, yet tobacco use remains high. To determine whether and how the tobacco industry targets military personnel in wartime, we analyzed internal industry documents about the Gulf War (1990–1991) and constructed a historical case study. During this conflict, tobacco companies targeted troops with free cigarettes, direct advertising, branded items, ways to communicate with family, and “welcome home” events. Military authorities sometimes restricted this activity, but frequently enabled it; tobacco companies were regarded as benefactors.

Considering tobacco use a benefit undermines military health priorities. Stronger policy is needed to reframe tobacco use as incompatible with military ideals.
Menu Labeling as a Potential Strategy for Combating the Obesity Epidemic: A Health Impact Assessment
Authors: Kuo Tony , Jarosz Christopher J. , Simon Paul , Fielding Jonathan E.
Published: July 2009

Objectives. We conducted a health impact assessment to quantify the potential impact of a state menu-labeling law on population weight gain in Los Angeles County, California.

Methods. We utilized published and unpublished data to model consumer response to point-of-purchase calorie postings at large chain restaurants in Los Angeles County. We conducted sensitivity analyses to account for uncertainty in consumer response and in the total annual revenue, market share, and average meal price of large chain restaurants in the county.

Results. Assuming that 10% of the restaurant patrons would order reduced-calorie meals in response to calorie postings, resulting in an average reduction of 100 calories per meal, we estimated that menu labeling would avert 40.6% of the 6.75 million pound average annual weight gain in the county population aged 5 years and older. Substantially larger impacts would be realized if higher percentages of patrons ordered reduced-calorie meals or if average per-meal calorie reductions increased.

Conclusions. Our findings suggest that mandated menu labeling could have a sizable salutary impact on the obesity epidemic, even with only modest changes in consumer behavior.
Planning for Posttrial Access to Antiretroviral Treatment for Research Participants in Developing Countries
Authors: Shah Seema , Elmer Stacey , Grady Christine
Published: July 2009

Despite recognition of the importance of posttrial access to antiretroviral therapy (ART), the implementation process has not been studied. We examined whether the National Institutes of Health (NIH) guidance document was being implemented in NIH-funded ART trials conducted in developing countries between July 2005 and June 2007.

All of the 18 studies we identified had posttrial access plans for trial participants. More than 70% had specific mechanisms for posttrial access, but none guaranteed long-term sponsor funding after the trials. The plans reflected variation in local contexts and the uncertainty of predicting local conditions in the long term.

The strength of the NIH guidance document may be that it encourages investigators to formulate plans in advance and to work with other stakeholders to provide access to ART.
A New Method for Evaluating the Productivity Index of Nonlinear Flows
Authors: Aulisa Eugenio , Ibragimov Akif , Walton Jay R.
Published: July 2009

This paper addresses the effects of nonlinearity of flows on the value of the productivity index (PI) of the well. Experimental data show that, during the dynamic process of hydrocarbon recovery, the PI stabilizes to some constant value, which, in general, is a nonlinear function of both the pressure drawdown and the production rate.

Linear Darcy flow is well understood, and excellent approximate formulas are available for the PI in various well/reservoir geometries. To handle the more realistic nonlinear situation, the current practice is to solve the nonlinear problem multiple times for different values of production rate and then add ad-hoc corrective parameters in the linear formulas to reproduce the nonlinear nature of the flow.

In this paper, we propose a rigorous framework to measure the PI of a well for nonlinear Forchheimer flows. Our approach, based on recent progress in the modeling of transient Forchheimer flows, uses both analytical and numerical techniques. It provides, for a wide class of reservoir geometries, an accurate relation between the PI for nonlinear Forchheimer flows and the PI for linear Darcy flows.

The proposed method of building look-up tables and analytical formulas serves as an effective tool for fast PI evaluation in nonlinear cases.
Infinite-Acting Physically Representative Networks for Capillarity-Controlled Displacements
Authors: Behseresht Javad , Bryant Steven L. , Sepehrnoori Kamy
Published: July 2009

Drainage/imbibition simulations are traditionally performed on finite regular lattices. If physically representative networks are used instead, the spatial correlation of pore space features inherent in granular materials is automatically accounted for. However, even these networks are obtained from finite samples, and conditions must be specified on the boundaries. Making the conditions correspond to physically realistic situations is difficult, especially for simulations of phase trapping. This paper presents a method of constructing infinite-acting model rocks, in which a well-defined criterion for phase trapping is possible that is independent of boundary conditions. The foundation of the model is computergenerated dense random periodic packings of spheres. We illustrate the method with simulations of drainage and irreducible wetting-phase saturations. To eliminate possible confounding effects from grains being arranged differently, we compare simulations in infinite-acting networks with simulations in the finite network taken from the unit cell of the periodic packing. Wetting-phase connectivity is assessed globally and accounts for all phase morphologies, including pendular rings.

The drainage endpoint for a finite network was highly sensitive to the number and location of the exit pores; while using the infinite-acting network, we removed this latter sensitivity. Comparison with experiments showed that a strict criterion of wetting-phase connectivity (pores connected only by throats filled with wetting phase) cannot account for typical values of Sw,irr and that connectivity must persist via pendular rings.

Typical laboratory experiments and simulations in finite networks yield drainage curves that approach irreducible wetting phase saturation Sw,irr gradually, with large changes in capillary pressure inducing only small changes in saturation. Simulations in infinite-acting networks do not exhibit this behavior. We argue that these simulations are more representative of behavior in the field and that typical laboratory measurements underestimate the value of Sw,irr.
Experimental Study of CO2 Injection Into Saline Formations
Authors: Cinar Y. , Riaz A. , Tchelepi H. A.
Published: July 2009

We present laboratory experiments to investigate the influence of gravitational, viscous, and capillary effects on the CO2 injection process. Quasi 2D experiments are performed in a vertical glass-bead pack in the parameter range of interest for CO2 sequestration in deep aquifers (i.e., with Bond numbers of approximately 10−3 and capillary numbers on the order of 10−4). The objective is to investigate the type of flow regimes that occur under favorable as well as unfavorable conditions of density and viscosity. The experiments demonstrate the existence of pore-scale instability in the presence of unfavorable gradients of viscosity and density. Consequently, conventional mathematical models may not be able to represent these unstable flows appropriately. A comparison with estimates from percolation theory shows reasonably good agreement with experimental observations.
A Novel Hydraulic Fracturing Model Fully Coupled With Geomechanics and Reservoir Simulation
Authors: Ji Lujun , Settari A. , Sullivan R. B.
Published: July 2009

Unconventional fracturing techniques, such as high-rate waterfracs, waterflooding, or steam stimulation, produced water and cuttings reinjection, CO2 sequestration, and coalbed methane stimulation, are difficult to model because of strong interactions among the fracturing process, geomechanical changes in the porous media, and reservoir fluid flow. The resulting strong poroelastic/thermoelastic effects, permeability and porosity changes, and possible rock failure make current conventional fracturing models inadequate in such circumstances. Therefore, it is necessary to develop new models that include all of these mechanisms and that are capable of conducting integrated data analysis.

This paper presents a new fracturing model with all of these mechanisms included. The model fully couples fracture mechanics with reservoir and geomechanics simulation. This methodology allows us to model fracture initiation and propagation, post-frac multiphase cleanup in the reservoir and fracture and pre-frac and post-frac well performance in a changing stress and pressure environment, all within the same system.

The model couples a 3D finite element geomechanics model with a conventional 3D finite difference reservoir flow simulator. The geomechanics module implicitly models fracture propagation via displacements on the fracture face. The flow and geomechanics/fracturing are coupled in an iterative manner that is equivalent to full coupling of geomechanical and reservoir flow modeling. The 3D (planar) fracture geometry and the pressures in it are the common dynamic boundary conditions for the flow and stress modules. The new iterative process yields smooth fracture propagation, and the model has been tested on classical fracturing problems.

A field example demonstrates the validity and advantages of the approach. To illustrate the model capabilities, we model a waterfrac stimulation performed in Bossier tight-gas sands. The model results show that the model is capable of matching complex injection history and calibrating the stress-dependency of formation permeability.
Effect of Droplet Size on the Reaction Kinetics of Emulsified Acid With Calcite
Authors: Al-Mutairi S. H. , Nasr-El-Din H. A. , Hill A. D. , Al-Aamri A. D.
Published: July 2009

Unlike other acid systems, such as gelled and viscoelastic surfactant-based (VES) acids, where the mobility of hydrogen ion controls the overall rate of the reaction, emulsified acid/calcite reaction involves the transport of acid droplets in the diesel phase to the rock surface, breaking of acid droplets, and then the actual reaction on the surface. A limited number of papers have been published on the reaction kinetics of emulsified acid. However, none of the published work considered the effect of acid droplet size on the reaction of emulsified acid. The objective of this work is to examine the effect of the acid droplet size on the reaction rate of emulsified acid with calcite.

The acid was 15 wt% HCl emulsified in diesel with 70:30 acid/ diesel volume ratio. The emulsifier concentration was varied from 1 to 10 gpt. All emulsions were characterized by measuring the droplet size distribution, viscosity, and thermal stability. Diffusivi-ties were measured using the rotating disk device. The experiments were carried out at 25, 50, and 85°C, under 1,000 psi pressure, and disk rotational speeds from 100 to 1,000 rev/min. Samples of the reacting acid were collected and analyzed to measure calcium concentration in the reactor.

The effect of the acid droplet size on the overall reaction rate was significant. The diffusion rate of acid droplets to the surface of the disk was found to decrease with increasing emulsifier concentration because of higher viscosities and smaller droplet sizes. The effective diffusion coefficient of emulsified acid was found to increase linearly with the average droplet size. Emulsions with low emulsifier concentrations (1 gpt) had average droplet sizes of nearly 13 μm. These emulsions were found to have high effective diffusion coefficients (5.093 × 10-9 cm2/s) and low retardation. On the other hand, emulsions with high emulsifier concentrations (10 gpt) had smaller average droplet sizes (nearly 6 μm) and found to have low effective diffusion coefficients (4.905 × 10-11 cm2/s) and high retardations.

The new sets of data can be used to determine the optimum emulsified acid formulation to yield deeper acid penetration in the formation. It is suggested that droplet size can be adjusted to produce the desired diffusion coefficients for acid fracturing treatments.
Completion Analysis and Tracer-Derived Proppant Distribution Improve Completions in the Piceance Basin
Authors: Balderston M. A. , Stabenau J. D. , Holcomb D. L.
Published: July 2009

In June 1996, a two-phase project was initiated to determine how multiple zones react to fracture-stimulation treatments in the Mesa Verde formation, which is located in the Piceance Basin of the western Rocky Mountain Region in the U.S. On the basis of the collected information, study participants evaluated and redesigned procedures to increase the operator's profitability. Limited-entry fracturing was used as the primary fracturing technique, and a multiple-isotope, spectral gamma ray imaging tool was used for evaluating early, middle, and late proppant distribution with three isotopes. During the two-phase project, 20 wells and 218 sands were perforated and targeted for stimulation.
Cleaning Wells from Unexpected, Contaminated Polymer Mud: A State-of-the-Art; Case History
Authors: Talabani Soran , Al Jaberi Salem , Efnik Mohamad S.
Published: July 2009

The presence of the remaining, non-damaged drilling fluid in the well bore before completion might lead to a complicated situation. Furthermore, the non-damaged fluid may generate a kind of sticky material when it interacts with Calcium or potassium ions present in the formation water, hydrogen sulfide, and hydrochloric acid during acid job.

The sticky material found in some wells was spongy and restricted the oil flow rate. None of the production logging tools was able to record data in the presence of this material.

It is believed that a chemical interaction took place between a modified polymer present in the drilling fluid with some higher rank ions than sodium. This interaction releases the trapped water and results in polymer molecules that are polarized with some oil molecules in the presence of a very low pH solution such as a continuous phase (acid). This resulted in a sticky material that could not penetrate the formation but restricted the flow rate.

In this paper the possible reasons for the creation of this material and their chemistry are addressed, the presence of the materials that caused it, and possible solutions that dissolve this material without altering the pay zone rock properties.

Case history from one field shows that in order to avoid the creation of this sticky material, horizontal wells should be totally cleaned and displaced by water before any acid job application.

The chemical that is used to dissolve this sticky material is environmentally safe, causes no damage to the formation pay zone and is economic to use.
The Use of Real-Time Automation to Further Production System Optimization in the Oil Industry
Authors: Cramer Ron , Dunham Cleon , Al Hinai Alley
Published: July 2009

The oil industry is a mature user of SCADA systems, moving from basic monitoring and control into utilizing real time data to optimize the process. Optimization capabilities are improving the economics of oil and gas production operations facilitating production of low cost oil.

The paper outlines the components of "production system optimization" currently being implemented with special emphasis on real time capabilities. Specific examples from Oman are included to show how the technology is improving the life-cycle economics.
A Gas Field Automation System for Enhancing Production and Well Safety
Authors: Reyes Alfonso , Plunkett Joe , Teja Ricardo , Zambrano Oscar
Published: July 2009

The automation of the high-production Ramos gas field, located in the northern region of Argentina, has enhanced field production and well safety and has improved operations by centralizing control of the gas production. A field supervisory control and data acquisition (SCADA) computer located in the gas treatment plant automates the gas production throughout the field by means of a radio telemetry link to a well control unit (WCU) located at each automated well site. Operations personnel can monitor production variables from the plant at any site, view real-time or historical trends of those variables, or change setpoints in a WCU from graphical screens on the computer console. In addition, the production data is archived to a hard disk for further processing and analysis.

Currently, the automation system involves six wells. Five additional wells will be automated during 1999. A solar-powered WCU located at each site controls well production by means of an electrically activated choke. This microprocessor-based controller monitors operating pressures, temperatures and tank levels, and it ensures well and flow-line safety by controlling the operation of the surface safety valve (SSV) and the sub-surface safety valve (SSSV).
Proactive Risk-Assessment-Based Management
Authors: Gruver Steve
Published: July 2009

Traditional management techniques tend to address events in a reactive manner. Many of the documents that are produced in managing day-to-day activities, including morning reports and safety statistics, cover events that have already taken place. With this information in hand, management takes steps to minimise the effects of the action that has taken place and makes further plans to prevent a reoccurrence. This can lead to a cycle in which there is insufficient time to pro-actively plan and look ahead due to the amount of time required to react to events that have already happened. With this in mind, a trial was conducted using an active pro-active risk-assessment based management technique with positive results in accident statistics, personnel turnover and unplanned events.
The Success of Steerable Ream While Drilling Technology Applied in Valhall Field-Norway
Authors: Kinn Sigurd , Marshall Gai-Lynn E. , Poerschke Wilfried , Christensen Hughes , Froehlich Norbert
Published: July 2009

As part of a major oil company's objective to save rig time as well as reduce open-hole exposure time in the Valhall overburden, steerable ream while drilling technology was utilized in their deviated and horizontal wells to eliminate under-reaming thus reducing drilling costs.

The well paths require good directional control with holding capability while drilling long tangent sections. Since a single assembly is designed, the rotary steerable assembly must be capable of programmable dog leg generation when changing inclination and direction or geosteering in the horizontal section.

This paper describes the application of steerable ream while drilling in different hole sections on several wells. Case studies will be presented from wells drilled from the Valhall platform by a jack up rig cantilevered over the wellhead platform. The authors will outline the reasons for utilizing SRWD's and the operational achievements of the system while drilling well F-8, particularly in the two largest hole sections where the tool saved 10-12 days of rig time.

The problems observed while drilling directional and horizontal well paths with steerable motor assemblies will be presented in addition to the modifications implemented as solutions. These improvements should make it possible to further improve ROP and steering abilities on future wells. Additionally, the authors will discuss the improvements achieved by applying new cutter technology and design changes for stabilization of the pilot bit.
Deep-Bed Filtration Under Multiple Particle-Capture Mechanisms
Authors: Guedes R. G. , Al-Abduwani F. , Bedrikovetsky P. , Currie P. K.
Published: July 2009

Severe injectivity decline during seawater injection and produced-water reinjection is a serious problem in offshore waterflood projects. The permeability impairment occurs because of the capture of particles from injected water by the rock, both internally in the pores and externally in a filter cake. The reliable modeling-based prediction of injectivity decline is important for injected-water-treatment design and management (injection of seawater or produced water, water filtering, etc.).

The classical deep-bed filtration model includes a single overall description of particle capture. During laboratory or field data interpretation using this model, it is usually assumed that several simultaneously occurring capture mechanisms are represented in the model by a single overall mechanism. The filtration coefficient, obtained by fitting the model to the laboratory or field data, represents the total kinetics of the particle capture. The purpose of this study is to justify this approach of using an aggregated single filtration coefficient.

A multiple-retention deep-bed filtration model needs to describe several simultaneous capture mechanisms. The kinetics of the different capture mechanisms can differ from one another by several orders of magnitude. This greatly affects the particle propagation in natural reservoirs and the resulting formation damage. In this study, a model for deep-bed filtration taking into account multiple particle-retention mechanisms is discussed. It is proven that the multicapture model can be reduced to a single-capture-mechanism deep-bed filtration model. The method for determination of the capture kinetics for all individual capture processes from the breakthrough curve is discussed. As an example, the complete characterization of filtration with monolayer and multilayer deposition of iron oxide colloids is performed using particle-breakthrough curves from coreflooding.
Global Warming Solutions and the Path to Recovery
Authors: Foster David
Published: July 2009

We will look back on the last year as a period when extraordinary economic events marked the unraveling of one economic model and placed in front of the global community a set of choices. Either we restructure the architecture of the global economy and replace it with something else, or we face a future of devastating economic consequences. The Blue Green Alliance has become one of America's leading advocates for global warming solutions and we believe that the benefits and economic opportunities will far outweigh the costs. We have popularized the terms “green economy” and “green jobs” and we believe that every job in America should turn into a green job.
Challenges to Global Green Job Growth
Authors: Sweeney Sean , Kubit Jill , Renner Michael
Published: July 2009

The authors recognize that green is a relative term and that what's green today may be decidedly not green tomorrow. They developed the idea of “shades of green” to try to capture the differences between jobs and looked at where the green jobs currently are. They found that green jobs in renewables are likely to grow, but in other sectors green jobs face enormous challenges. Among them are investment, technology, agriculture, labor market, and urbanization hurdles.
Climate Policy Statement
Authors: Alliance The Blue Green
Published: July 2009

The four labor unions and two environmental organizations that comprise the Blue Green Alliance worked intensively during the fall of 2008 and winter of 2009 to craft a joint statement on comprehensive climate change policy. The United Steelworkers, Sierra Club, Communications Workers of America, Natural Resources Defense Council, Laborers International Union of North America, and Service Employees International Union together released a policy statement on climate change and energy in late March.

The goal of this undertaking is to articulate a framework by which the United States can rapidly put millions of Americans back to work building a clean-energy economy and reducing global warming emissions to avoid the worst effects of climate change.
Green Chemistry and Workers
Authors: Hughes Joseph (Chip) , Legrande Dave , Zimmerman Julie , Wilson Michael , Beard Sharon
Published: July 2009

What follows is a summary of remarks presented by panelists participating in a workshop entitled, “What Green Chemistry Means to Workers.” The session examined the connection between green jobs—including those connected to the emerging field of green chemistry—and occupational, public, and environmental health. It was coordinated by Paul Renner, associate director of the Labor Institute, in collaboration with the Tony Mazzocchi Center for Safety, Health and Environmental Education, a project of the United Steelworkers and The Labor Institute. It was moderated by Joseph “Chip” Hughes, Director, Worker Education and Training Program, National Institute of Environmental Health Sciences. Panelists included Julie Zimmerman, PhD, Assistant Professor of Environmental Engineering, Forestry and Environmental Studies, Yale School of Engineering and Applied Science and Assistant Director for Research, Green Chemistry and Green Engineering Center, Yale University; David LeGrande, Occupational Safety and Health Director, Communications Workers of America; Mike Wilson, PhD, MPH, Environmental Health Scientist, Program in Green Chemistry and Chemicals Policy, Center for Occupational and Environmental Health, Berkeley School of Public Health, University of California; and Sharon D. Beard, Industrial Hygienist, NIEHS Worker Education and Training Program.
A Chance to Create Jobs That Do Good
Authors: Jackson Lisa
Published: July 2009

America has the potential to create jobs that do much good. Green jobs are no longer a concept, they are a reality and they are vital to economic growth and a driver for economic recovery. Environmental issues will be swept up as we address the economy. The choices will never be between one green or the other. And labor must be a partner in this effort.
Green Schools: Strengthening Our Economy by Investing in Our Children
Authors: Weekes John M.
Published: July 2009

An architect looks at the history of school design and construction in the United States, which by 2008 had approximately 97,000 public schools holding 54.3 million students and five million teachers. About 73 percent of the schools were built prior to 1969. A study has shown that Green Schools can produce a 30–50 percent reduction in energy use, 35 percent reduction in carbon dioxide, a 40 percent reduction in water use, and cut 70 percent in solid waste. Further, student absenteeism and teacher turnover were reduced and productivity increased three percent. If all American schools were Green, the country would save nearly $1 trillion in the next 10 years.
Recycling: Not Just a Feel-Good Act but a Green Jobs Engine
Authors: Petty Celia
Published: July 2009

The U.S. needs to recycle its outdated recycling industry. It can bring good well-paying jobs, reduce harmful gas emissions, and energize markets and local economies. The U.S. recycles only a third of its wastes; even so, with 1.1 million employees, it grosses $236 billion a year. But now it must transform the operation into a resource recovery infrastructure.
Change is Happening
Authors: Klobuchar Amy
Published: July 2009

Americans have a new perception of our problems. They now see the economics of conservation. Elected officials also have seen it and are taking more bipartisan approaches. People “get it” as they see opportunities for change. And, in contrast with the Information Technology revolution, the Energy Technology revolution, providing we do it right, will bring change across the country and across demographic groups. This revolution will be more broad-based. Now, we have a President with a message and a Congress ready to act.
Embracing a Clean-Energy Future
Authors: Sebelius Kathleen
Published: July 2009

The former governor of Kansas describes how her state is greening. The Blue Green Alliance has estimated that in a renewable-energy economy, Kansas stands to gain more than 11,000 jobs and almost $2 billion in new economic investments.
Start Your Engines
Authors: Pope Carl
Published: July 2009

The Sierra Club's Carl Pope reads the signs that say “this is the time” for change.
Renew, Refuel, and Rebuild
Authors: Chin Allison
Published: July 2009

We can renew, refuel, and rebuild America with millions of green jobs, but they must be good jobs. Participants at the conference understand that environmental and economic stability go hand-in-hand, that the challenges of global warming are urgent and that huge opportunities exist for building a clean energy economy.
Ensuring That Green Jobs are Good Jobs
Authors: Beard Sharon
Published: July 2009

A priority of the National Institute of Environmental Health Sciences' (NIEHS's) Worker Education and Training Program (WETP) is to make sure that green jobs are good jobs: they must be safe jobs and must include strong safety training programs. The Laborers AGC Education and Training Fund (LAGC) of the Laborers International Union of North America has been a grantee of the WETP for years and has developed hands-on, peer-focused, state-of-the-art health and safety training for laborers in the environmental remediation field. NIEHS has worked with union President Terence O'Sullivan and the LAGC to train workers engaged in freeing our communities from the extensive legacy of industrial pollution.