bluuebunny/crossref_metadata_2025 huggingface dataset:
C-Reactive Protein in Neonatal Sepsis
Authors: Hawk Michelle
Published: November 2011

SEPSIS IS ONE OF THE MOST COMMON diagnostic challenges in the NICU. Currently a definitive diagnosis can be made only with the gold-standard blood culture, which is generally not available for 48 hours.1,2 Difficulty obtaining a large enough sample to detect a positive blood culture, as well as increased use of antenatal antibiotics, has complicated the ability to make a definitive diagnosis of sepsis.3 If left untreated, sepsis can increase morbidity and mortality. Therefore, many infants are treated empirically with broad-spectrum antibiotics.4,5 Two kinds of tests would be most helpful in the diagnosis of neonatal sepsis: one that quickly confirms the diagnosis and one that conclusively rules it out. In fact, a diagnostic sepsis marker with a high negative predictive value (the value representing patients without sepsis who are correctly diagnosed) might reduce the short- and long-term adverse effects of antibiotics, health care costs, and length of hospital stay.6 Despite extensive investigation no single test meets the criteria that would make it an ideal marker for the early diagnosis of sepsis in the newborn.5,7,8 Generally, screening includes a complete blood count with differential and may be accompanied by other adjunctive tests such as a C-reactive protein (CRP).9–11 This column examines CRP, an acute phase reactant (APR), as a diagnostic marker for neonatal sepsis.
Insulin Infusion for the Treatment of Hyperglycemia in Low Birth Weight Infants: Examining the Evidence
Authors: Raney Mary , Donze Ann , Smith Joan Renaud
Published: November 2011

FORTY TO 80 PERCENT OF VERY LOW birth weight (VLBW) (infants <1,500 g) and extremely low birth weight (ELBW) (infants <1,000 g) infants will develop hyperglycemia when provided with glucose infusions adequate to meet basal metabolic needs.1,2Avoiding hyperglycemia while providing adequate nutrition to promote growth and development is a major challenge for health care providers in the NICU. Some health care providers suggest that the judious use of continuous insulin infusion (CII) may provide the opportunity for increasing nutritional support while maintaining euglycemia. A systematic review of the literature is presented to evaluate the evidence supporting this practice.
An Invitation to Push Yourself
Authors: Askin Debbie Fraser
Published: November 2011

RUNNING A MARATHON IS ALL ABOUT PUSHING THE human body farther than its meant to go: Beyond the point where glycogen is available, beyond the point where muscles cease complaining and just plain cramp up. Doing a Google search on “pushing yourself” yields all kinds of references to running, training, triathlons, just about any type of physical training imaginable.
The Changing Role of Parents in Neonatal Care: A Historical Review
Authors: Thomas Lori
Published: November 2011

Over the past century, improvements in technology and neonatal care techniques have dramatically reduced infant mortality rates. While this progress continues, a growing body of literature supports the significant role that parents play in the development of infants, particularly within the hospital setting. Throughout much of the twentieth century, various barriers prevented many parents from participating in the care of their neonates, negatively influencing infant outcomes. Today parental involvement in neonatal care has become a key part of a larger familycentered care model. This historical review describes how past neonatal care practices affected the roles of parents, from absence or indirect involvement to the important involved roles of today. Understanding current trends in relation to these past experiences may encourage the formulation of family-centered care practices now and in the future.
Babies and Public Policy
Authors: McCain Gail
Published: November 2011

WE CARE ABOUT GIVING THE BEST CARE TO OUR INFANT patients while they are hospitalized in our nurseries, and we care about their welfare after we discharge them home. We love it when our “graduates” return to visit and they are healthy, growing, and developing appropriately. As nurses and citizens, we need to be aware that all social policies impact infants. The presidential contenders are addressing policies related to health care, poverty, Head Start, immigration, substance abuse, employment, and child care. How we deal with all these issues has the potential to affect infant growth, development, and well-being.
Neonatal Glucose Homeostasis
Authors: Milcic Terri Lynne
Published: November 2011

NEWBORNS ARE NURTURED in a uterine environment that provides and regulates their glucose supply. Once the umbilical cord is clamped and the maternal glucose supply is terminated, the neonate must begin glucose regulation. This regulation involves complex metabolic and hormonal pathways that may not be mature immediately after birth. A variety of factors influences maturation of these pathways, including developmental immaturity, gestational age, maternal influence, delivery history, and any existing disease processes.1 Management of glucose homeostasis is further complicated because a “normal” range for neonatal blood glucose values has not been clearly defined.2–6 The practitioner must be astute at identifying neonates at risk for glucose problems and intervene quickly because prolonged glucose imbalance can cause serious neonatal complications.
Implementing NICU Critical Thinking Programs: One Unit’s Experience
Authors: Zimmerman Denise , Pilcher Jobeth
Published: November 2011

Critical thinking is the hallmark of today’s nursing practice environment. Nowhere is this more critical than in the high-tech environment of the NICU. Despite the importance of critical thinking in nursing practice, there is limited information on the process of teaching new NICU nurses to think critically. Based on the principles of adult education, orientation and continuing education for NICU nurses should be goal directed, build on the learner’s prior experience, and build in opportunities for active participation, reflection, and experiential learning. This article reviews the principles of adult education and their application to the process of teaching critical thinking in the NICU. One unit’s experience of critical thinking education is used to provide concrete examples of how NICU education can be transformed from a traditional didactic methodology to a more dynamic experiential approach.
Bicarbonate and Chloride Equilibrium and Acid-Base Balance in the Neonate
Authors: Shaw Amy
Published: November 2011

MAINTENANCE OF ACID-BASE equilibrium in the neonate is a challenge in the face of illness or prematurity. Neonatal growth and development and the proper functioning of all organ systems of the body are dependent on maintaining a normal serum pH. Neonates encounter in the normal transitional period many stresses that can cause acid-base imbalance. In addition, premature neonates are more susceptible to acid-base imbalance because their compensatory responses are limited. Factors associated with acid-base imbalance seen in the newborn period include respiratory distress, sepsis, hypovolemia, perinatal stressors, and prematurity.1–4
The DNP Storm
Authors: Johnson Patricia
Published: November 2011

I DON’T REMEMBER THIS LEVEL OF PASSIONATE DISAGREEMENT over a nursing role since the birth of the neonatal nurse practitioner/clinician in the 1970s. At that time, a handful of nurse and physician visionaries saw the merits of advancing nursing practice in an acute setting; but most leaders in both organized nursing and medicine objected to the role’s potential to blur traditional professional lines.
Music as a Nursing Intervention for Preterm Infants in the NICU
Authors: Neal Diana , Lindeke Linda
Published: November 2011

Although there is general agreement that noise in the neonatal intensive care unit should be reduced, there is controversy about the use of music as a developmental care strategy with preterm infants. Much literature supports using music with preterm infants, indicating that it enhances physiologic and neurobehavioral functioning, but some experts worry that music is overstimulating. This article presents evidence supporting the use of music with preterm infants as well as criticism of same. Recommendations for music interventions with preterm infants are discussed, although further research is needed before specific guidelines can be established.
Analysis of Cerebrospinal Fluid in the Neonate
Authors: Pacatte Kimmie
Published: November 2011

NEONATES PRESENTING WITH apnea, seizures, signs and symptoms of infection or neurologic disorders often require evaluation of cerebrospinal fluid (CSF) as part of their diagnostic workup. Multiple studies can be done on CSF, including, but not limited to, evaluation of color, bacterial culture and Gram’s stain, viral culture, cell count and differential, polymerase chain reaction (PCR), and quantitative determination of a number of laboratory values. Proper evaluation of CSF depends on knowing which tests to order, normal ranges for the patient’s age, and the limitations of the test.1Reference ranges for CSF studies have been well established in the adult, but are not as well defined in the neonatal population.2,3This situation is further complicated by the vast differences between preterm and term infants. This column covers the interpretation of the most common tests done on CSF in the neonate. Many of the references cited are more than ten years old, but little new data support changes in the interpretation of neonatal CSF studies.
Letters
Authors: Shirland Lee
Published: November 2011

I am writing concerning an article titled “Neonatal Peripherally Inserted Central Catheters: Recommendations for Prevention of Insertion and Postinsertion Complications,” published in Vol. 27, No. 4 (July/August 2008), pages 245– 257. Of concern are Figures 3 and 4 on page 253 titled securing the catheter with adhesive skin closure strips and looping the catheter. The instructions and pictures demonstrate how to secure the catheter using skin closure strips and show the strips placed over the catheter. This is of great concern. The manufacturer’s recommendations on BD L-Cath System state the following on page 8 line 26, “Secure the catheter and dress the site with a sterile dressing. Tapes and securing devices should never be applied directly to the non-protected catheter.” This caution is echoed in the article titled “Tiny Patients, Tiny Dressings: A Guide to Neonatal PICC Dressing Change,” published in Advances in Neonatal Care, Vol. 8, No. 3, pages 141–162. The author states the following, “Some hospitals use skin closure strips. If these are utilized, manufacturer’s recommendations should be followed, and they should never be placed directly overlying the catheter to avoid catheter breakage and embolism.” The author supports this statement with the following reference, Frey AM. PICC complications in neonates and children. Journal of Vascular Access Devices. 1999: 17–26. It is clear that skin closure strips used to secure the peripherally inserted central catheter pose great risk and must never be applied directly over the catheter. Thank you for sharing this important information with your readers.
Fad, Frenzy, or Future? A Review of the Institute of Medicine’s Report on the Direction of Evidence-Based Practice
Authors: Smith Joan Renaud , Donze Ann
Published: November 2011

OVER THE PAST TWO YEARS, this column has had a dual purpose: presenting systematic reviews of neonatal clinical practice issues and providing readers with tools needed to utilize the evidencebased practice (EBP) process. We presented detailed examples of applying EBP to answer these reallife clinical practice problems:
Scalp IV or Graduation Tassel? Differing Perspectives of the NICU Experience
Authors: Lord Anne
Published: November 2011

FAMILY-FRIENDLY/FAMILY-CENTERED care in the NICU contributes to positive patient outcomes, strong families, and excellence in care. Successfully integrating the patient’s family into the care team in the high-tech, high-stress NICU environment can pose many challenges to the nursing staff. A significant obstacle to successful family-professional partnerships is lack of understanding by NICU professionals of parental perspectives of the NICU experience. This column provides unique insight into the differing perspectives of one infant’s family and the NICU staff who cared for him.
Serum Anion Gap in Metabolic Acidosis
Authors: Mandell Ivy
Published: November 2011

METABOLIC ACIDOSIS, DEFINED AS A pathophysiologic state characterized by an arterial pH <7.35 in the absence of an elevated partial pressure of carbon dioxide in arterial blood (PaCO2), is a common finding in the critically ill neonate. It is the result of excess acid production, decreased renal excretion of acid, or increased loss of base.1,2In the neonatal period, metabolic acidosis is most often the result of shock or severe liver or kidney failure. In rare cases, however, it may be a discrete finding suggestive of an inborn error affecting acid production or renal acid excretion.3Left untreated, this acidosis can disturb many cell functions, potentially resulting in respiratory distress, pulmonary vasoconstriction, right ventricular dysfunction, tachycardia, myocardial depression, increased intracranial pressure, hyperkalemia, insulin resistance, decreased affinity of oxygen for hemoglobin, abdominal distention, or vomiting.4Although the most common treatment for acidosis is to “correct” it with bicarbonate (HCO3−), this therapy is not without its potential adverse effects. Therefore, correction of the underlying cause is considered to be the most important therapeutic measure in the management of metabolic acidosis.3,5Calculation of the anion gap is a useful and inexpensive tool with which to develop a differential diagnosis for metabolic acidosis in the neonate. This column examines the usefulness and limitations of calculating the serum anion gap.
Recognizing Craniosynostosis
Authors: Merritt Linda
Published: November 2011

Craniosynostosis is characterized by the fusion of sutures. It presents with an abnormal head shape. This article examines this defect and discusses its embryologic origin. A systemic physical assessment guide serves as a tool to enhance early recognition of this defect. Pictorial examples increase understanding of the defect. A discussion of treatment and nursing implications, with an emphasis on family support, is provided.
Feeding Challenges in the Late Preterm Infant
Authors: Cleaveland Karen
Published: November 2011

A late preterm infant is defined as one born between 34 and 36 6/7 weeks of completed gestation. The rate of late preterm births has risen 18 percent since the late 1990s. Data are beginning to emerge concerning morbidity rates and the risks these newborns face with regard to feeding difficulties, temperature instability, hypoglycemia, and hyperbilirubinemia. Feeding challenges place these vulnerable infants at risk for prolonged hospital stays and readmission after discharge. To better address the unique needs of late preterm infants, providers should establish individual feeding orders. This article offers research-based suggestions for caring for these infants in the newborn nursery and the postpartum unit as well as parent teaching guidelines.
The Role of Qualitative Research in Evidence-Based Practice
Authors: Broeder Jennifer , Donze Ann
Published: November 2011

EVIDENCE-BASED PRACTICE ensures that the best care is provided to patients and families, and the results include improved patient outcomes and satisfaction. As nurses master evidence-based practice, they are faced with searching out the best evidence to support assessments and interventions, refine policies, and develop new practices. Determining what is strong evidence and what is not is a complex task. Both quantitative and qualitative research methods generate valuable knowledge for our practice; however, it is critical to identify which type of evidence provides the best answers for specific practice questions. Quantitative evidence provides the empiric knowing necessary for practice, and qualitative evidence supports the personal and experiential knowing critical for practice. Qualitative research presents its findings through participants’ words and stories, which are easily applied to nursing care practices. Nurses are attracted to qualitative research because its methods and findings often emulate the art of nursing practice, where understanding the whole patient and knowing patients individually matters. Yet qualitative research has not always been considered sound evidence for practice.1 It has been accorded lesser importance than quantitative research, which has been the gold standard. Researchers are working to justify the importance of qualitative research to clinicians and fellow researchers and to identify its role in evidence-based practice.2,3
Support Groups: An NICU Nurse’s Best Friend
Authors: Discenza Deb
Published: November 2011

AT TIMES, NICU PROFESSIONALS MAY be at a loss as to how they can provide additional emotional support for the families in their care. A hospital-based NICU or community-based preemie support group can help bridge the gap.
Wolff-Parkinson-White Syndrome in Infants
Authors: Hermosura Tisha , Bradshaw Wanda
Published: November 2011

Wolff-Parkinson-White (WPW) syndrome is a ventricular preexcitation that presents as supraventricular tachycardia. Health care professionals can attain optimal results in caring for infants with WPW syndrome by understanding both its pathophysiology and proper management to prevent and treat complications associated with it. This article reviews the prevalence, pathophysiology, clinical manifestations, diagnostic modalities, assessment, and management of WPW syndrome.
Fetal Fibronectin: What Does It Mean?
Authors: Nash Patricia
Published: November 2011

LIKE MANY STAFF NURSES AND neonatal nurse practitioners (NNPs), I work at two different hospitals as part of my full-time job and at a third hospital in a PRN position. Working at several different institutions affords the opportunity for multiple and varied learning experiences. One of the hospitals is a busy center for high-risk labor and delivery. As part of the NNP duties there, I attend board report three times per day. This entails a detailed discussion of all women in labor and delivery, primarily focusing on the high-risk patients. Fetal fibronectin (fFN) is a common topic of discussion during board report. I thought that fFN helped the perinatologist determine whether or not the woman was in labor and in imminent danger of delivery, but that was all I knew. Like other authors of articles in this column, I used my knowledge deficit as the impetus to research this topic. Therefore, this column briefly discusses the burden of preterm delivery and the methods used to identify women at risk for preterm birth. It focuses specifically on fFN: what it is, how it is measured, what the test means, and the predictive value of the test.
Is Your Nursery Full of MDROs?
Authors: Scheans Patricia
Published: November 2011

MULTIDRUG-RESISTANT ORGANISMS (MDROs) or multiresistant organisms are a significant and growing concern to all of us. Late-onset methicillin-resistant Staphylococcus aureus (MRSA) infections in the NICU are reported to have increased by 308 percent from 1995 to 2004.1 The Centers for Disease Control and Prevention (CDC) Healthcare Infection Control Practices Advisory Committee considers the prevention and control of MDROs a national priority, one that requires administrative and scientific leadership. This campaign will take commitment of financial resources, as well as of human resources devoted to practice improvement, expert consultation, laboratory support, monitoring of adherence to the practices that help with the problem, and data analysis.2 Unfortunately, this trend holds in developing countries as well. MDROs are a clinical challenge the world over.
Podcasts, Webcasts, Sims, and More: New and Innovative Ways for Nurses to Learn
Authors: Pilcher Jobeth , Bedford Laurie
Published: November 2011

ADVANCES IN TECHNOLOGY HAVE expanded the educational tools and learning options available to today’s nurses. Among these technologically enhanced tools and strategies are online learning, podcasts, vodcasts, webcasts, webinars, discussion forums, mobile learning, realistic simulations, and others. What exactly are these options? Which ones are the most effective? This is the first topic we will address in a new column on educational strategies in the NICU, a column designed to familiarize NICU nurse educators, clinical nurse specialists, managers, and preceptors with innovative and evidenced-based teaching strategies that promote optimal learning among NICU nurses. The purpose of this first column is to provide an introduction to innovative teaching tools and strategies—some technologically enhanced, some not—including such nontechnological interactive educational activities as problem-based learning, games, and concept maps. Future columns will discuss many of these strategies in more detail.
Triage, Not Just for the Emergency Department: A Discussion of the Appropriate Level of Care for the Transitioning Infant
Authors: Allison Beth Ann , Burcin Elizabeth
Published: November 2011

Determining the appropriate placement for infants experiencing a delay in transition or who require more intensive assessment, monitoring, and nursing care can be a challenge. Not all of these infants need to be admitted to the NICU. Since 1994, we have had a triage program to care for these infants. We define triage as a temporary (12 hours or fewer) level of care for monitoring, assessment, and intervention. This level of care is more intensive than in the newborn nursery, but the infant does not require an immediate NICU admission. Caring for these infants presents challenges in staffing, family-centered care, and reimbursement. This article shares information on the evolution of our triage program, its benefits to infants and their families, and how it is integrated into our NICU practices.
Protein C Deficiency
Authors: Kelly Alicia , Pearson Gregory D.
Published: November 2011

Protein C (PC) deficiency is a rare but life-threatening bleeding disorder that can present in the immediate neonatal period. This article presents the case of a baby girl with acute and progressive neonatal purpura fulminans as the presenting feature of PC deficiency. Other common complications of this disease include ophthalmic problems and central nervous system (CNS) changes. Management consists of correcting the coagulopathy, intensive wound care including negative-pressure dressings and skin grafting, and supportive care for the ophthalmic and CNS issues. Long-term follow-up consists of lifelong anticoagulant therapy to avoid recurrence of these complications.
BHA and Fluid Rheology Modeling: An Integrated Approach to Solving Complex Unconventional Shale Play Challenges
Authors: Ibrahim Hani , Gidh Yashodhan , Purwanto Arifin , Bits Smith , Visinescu Valentin , SWACO M-I
Published: November 2011

The Bakken Shale is one of the largest, unconventional crude oil plays in the United States covering as much as 25,000 sq miles in the Williston Basin. The formation underlies portions North Dakota and Montana and is found at depths ranging from 9000ft to 10,500ft. Reserve estimates vary but the United States Geological Survey (USGS) has calculated risked undiscovered resources of up to 4.3 billion barrels of recoverable oil and bbl/cu ft equivalent using current technology. At this time the field is being developed with single, dual and triple-leg horizontal wells with laterals extending 4500ft to 9500ft into the formation.

However, drilling activity in the area has fluctuated as a result of changing oil prices. Accordingly, reducing overall operation costs is essential to the economic feasibility of each drilling project. Because of the significant impact on drilling costs, the correct selection and utilization of drilling equipment including bits, drilling fluids, hydraulics and downhole tools is paramount. To optimize operations, a holistic approach was adopted to create a drilling "road map" utilizing several application software systems. These software tools enable engineers to envision the specific drilling environment and tool/BHA interaction before the bit goes in the hole.

A recent Bakken project included expert drill bit selection, rock mechanics analysis, shock studies, drilling fluids and hydraulics optimization. The directional well plan was optimized with wellbore simulation software. In order to circumvent deficient options prior to and during actual drilling operations, multiple scenarios are simulated using a collection of detailed geological and offset drilling information. These results were studied, analyzed and assessed as the optimum drilling solution prior to submitting them to the operator. Finally, the service provider monitored and implemented the recommended engineered solutions.

The initial results were encouraging: Drilling days on Well 1 were reduced by 30% which represents a cost savings of $572,000USD while achieving the drilling target and delivering a high-quality wellbore. Building on this initial success, second and third wells confirmed the value of holistic optimization saving the operator 13 days ($676,000USD) and 16 days ($832,000USD) of rig time respectively.
An NMR Study on Shale Wettability
Authors: Odusina Elijah , Sondergeld Carl , Rai Chandra
Published: November 2011

Shales have become one of the leading unconventional gas resources in the world today, but a detailed understanding of their petrophysical properties still eludes most researchers. Wettability is an important rock property as it affects the recovery and stimulation methods and the quantity of hydrocarbon recovered. We present a study of shale wettability using Nuclear Magnetic Resonance (NMR) to monitor sequential imbibition of brine and oil (dodecane). Mineralogical variations, low permeability and porosity, complex pore structure, and the presence of organics complicate the interpretation of wettability in shale reservoirs and renders conventional approaches useless. The presence of organics has been reported to affect shales by reducing density, altering wettability, increasing porosity, amongst other effects. NMR, a non-destructive technique, has been applied to study wettability in other lithologies; we have applied it to study shale formations. A total of 50 samples were analyzed; 21 core plugs from the Eagle Ford shale, 12 from the Barnett, 11 from the Floyd shale, and 10 from the Woodford shale. Berea sandstone, known to be water-wet was analyzed and provides a calibration standard. Our NMR study confirms that Berea sandstone exhibits water-wet behavior. The shales studied imbibed both brine and oil, and the volume of oil imbibed is influenced by a combination of Total Organic Carbon (TOC), thermal maturity, and organic pore volume. The Woodford shale showed more affinity for dodecane compared to the other shales. The T2 NMR signature of the imbibed dodecane occurs mostly at relaxation times ranging from 2–20ms, much faster than its measured bulk relaxation of 1 second, suggesting that surface relaxation dominates the oil response in the shales. The observed brine T2 relaxation peak is predominantly below 1ms range, compared to its measured bulk value of 3 seconds. The shales display mixed wettability, with the organics contributing mainly to the oil-wetness. Exposure to drilling fluids could affect the "as received" wettability state of the cores; this effect needs to be investigated further. We extend our observations to explain the loss of hydraulic fracturing fluid in shale formations. Our study shows that imbibition of fracturing fluid by the formation is a possible cause of high fluid losses during hydraulic fracturing. Additionally, the possibility of estimating microfracture widths from T2 spectra was explored. Fracture widths ranging from 1–10 microns were estimated from the NMR T2 spectra, and this compared favorably with estimates from Micro-CT x-ray images.
Applying Computer Based Precision Drill Pipe Rotation and Oscillation to Automate Slide Drilling Steering Control
Authors: Gillan Colin , Boone Scott , LeBlanc Marc , Picard Randy , Fox Todd
Published: November 2011

While rotary steerable systems (RSS) have become the de facto system of choice in offshore drilling applications where day rates can often approach one million $USD, the choice of the most economic downhole drilling system for the land driller, and the future factory driller, is more complex. In the land market, although the RSS has made considerable technology leaps in the last 5 years in improving build rates and high temperature capabilities, the standard directional bent housing motor continues to dominate the land directional market and provide a viable economic alternative to the RSS. As an engineer from a major energy company once said at an SPE conference, "we look at all projects well to well, and if it was possible to drill it with a regular motor, then we will". Many directional drilling providers and operators will thus continue to use slide drilling for directional projects into the foreseeable future, and if as we maintain, the directional motor can be controlled and managed by a directional driller remote from the rigsite at a data center, then the industry will have made some progress towards automated directional drilling.
Estimation of Fracture Density and Orientation Through Azimuthal Processing and Interpretation of Seismic Data
Authors: Chaveste Alvaro , Hall Mike , Verm Richard , Gaiser Jim
Published: November 2011

The determination of fracture density and orientation is important in plays in which reservoir permeability is associated with micro-fractures. In these reservoirs, effective porosity is dependent upon the density of open fractures and permeability has a directivity component associated to the fractures’ orientation. Accurate determination of fracture density and orientation using surface seismic helps, then, in determining locations of good reservoir storability, as well as directional drilling orientation for optimum permeability. The anisotropy of P- and S-wave velocities is commonly associated with the magnitude and orientation of stress fields or open fractures and hence, is the medium through which factures can be characterized using surface seismic data.

A case study in the Marcellus Shale (NE United States) is presented in which PP and PS wide azimuth seismic data, acquired and processed to preserve the amplitude and velocity information of the source-receiver azimuth, are used to compute anisotropic attributes from which a qualitative analysis of fracture density and orientation is done.

The Marcellus Shale is known to have two sets of fractures (joints) associated to different tectonic events. Particular to this play is that one set of joints is perpendicular to the co-located macro-fractures. In this case, although curvature or other geometric attributes reveal the strike of macro-fractures, this does not correspond to the joint sets, which are at sub-seismic resolution. Anisotropy analysis through elliptical inversion of P-wave velocities identifies both sets of micro-fractures and verifies their expected position in relationship to the oroclinal belt and the macro-fractures. Analysis of PS migrated stacks supports these observations.
Investigation of Primary Recovery in Tight Oil Formations: A Look at the Cardium Formation, Alberta
Authors: Ghaderi S. M. , Clarkson C. R. , Kaviani D.
Published: November 2011

Tight oil formations (permeability <1 mD) in Western Canada have recently emerged as a reliable source of light oil supply owing to the use of multi-fractured horizontal wells. The Cardium Formation, which contains 25% of Alberta’s total discovered light oil (according to Alberta Energy Resources Conservation Board), consists of conventional and unconventional (low-permeability or tight) play areas. The conventional play areas have been developed since 1957. Contrarily, the development of unconventional play areas is relatively recent. The lag in development of the unconventional play is due to considerably poorer reservoir properties which increases the risk associated with capital investment. This in turn implies the need for a comprehensive and critical study of the area before planning any development strategy.

This paper presents performance results from the low permeability portions of the Cardium Formation where new horizontal wells have been drilled and stimulated in multiple stages to promote transverse hydraulic fractures. Development of the tight Cardium Formation using primary recovery is considered. The production data of these wells was first matched using a black oil simulator. The calibrated model presented was used for performance perditions based on sensitivity studies and investigations that encompassed design factors such as well spacing, fracture properties, and operational constraints. These simulation sensitivities were used to make economic predictions to assist with optimal design. In conclusion, based on our simulation results, we provide the operators of the Cardium tight portion with some recommendations to optimize both short and long-term profit.
Effective Caprock Determination for SAGD Projects
Authors: Collins P. M. , Walters D. A. , Perkins T. , Kuhach J. D. , Veith E.
Published: November 2011

In the oil sands of western Canada, caprock integrity has become a central issue in projects using steam injection recovery processes such as SAGD (steam-assisted gravity drainage). Caprocks contain steam and fluids within the reservoir and understanding the integrity of the caprock over the life of the operation is critical in order to ensure a safe and economically viable project.

A multi-disciplinary study was undertaken to evaluate geological facies as potential caprock for Ivanhoe Energy’s Tamarack project. This examination of the historical performance of operating SAGD projects correlated the maximum vertical growth of the steam chamber with geology and the steam-injection operating pressure. The study found that SAGD steam chambers are being constrained by geological facies grading upward to poorer reservoir quality rather than being constrained by shallower, regionally extensive, massive, low-permeability barriers.

Geomechanical reservoir simulations of Ivanhoe Energy’s proposed Tamarack SAGD Project predict that the steam chamber will be similarly constrained as reservoir quality degrades upward. The simulations show the pressure and stress gradients in the formations above the steam chamber as a function of time and operating conditions, allowing for a more accurate assessment of steam containment and the risk for shear and/or tensile failure.

The findings are significant because they confirm that the vertical growth of SAGD steam chambers has been effectively halted by facies consisting of interbedded sands and mudstones. These effective caprock facies have higher fracture pressures than the regionally extensive low permeability barriers because these facies are found at greater depths. The higher fracture pressure justifies a higher maximum operating pressure, with its associated higher reservoir temperatures resulting in much lower bitumen viscosities. As a result, SAGD well productivity and project economics are greatly improved, particularly for shallow SAGD projects.
Case Study of Using Basin Analysis to Evaluate Unconventional Gas Resources in Frontier Basins
Authors: Cheng Kun , Wu Wenyan , Holditch Stephen A. , Ayers Walter B. , McVay Duane A.
Published: November 2011

As gas production from conventional gas reservoirs in the United States decreases, the industry is turning more attention to the exploration and development of unconventional gas resources (UGRs). This trend is expanding quickly worldwide. However, unlike in many mature North American basins where significant development of UGRs is now routine, many countries are just turning to UGRs exploration. Insightful resource assessment is important for tapping UGRs in these frontier basins.

To evaluate the UGRs in frontier basins that are underexplored, we developed basin analysis methodology to 1) characterize basins; 2) establish analogs between frontier basins and mature North American basins; 3) estimate conventional and unconventional resources in mature North American basins; and 4) quantitatively predict UGRs in frontier basins by using information from analogous North American basins. This comprehensive basin analysis study not only validates the resource triangle, which is characterized by a large ratio of unconventional TRR (technically recoverable resources) to conventional TRR, but also makes it possible to quantitatively assess unconventional resources in under-explored basins worldwide.

To demonstrate use of basin analysis in evaluating the UGRs of frontier basins, two world hotspots for UGRs exploration were selected as the target basins: Neuquén basin in South America and Berkine basin in North Africa. Recent assessment reports and exploration activities indicate that the two basins have substantial unconventional gas resources. As a case study, basin analysis was used to identify the North American reference basins that are analogous to the Neuquén and Berkine basins, and to characterize the distributions of UGRs in these frontier basins. Furthermore, the quantitatively estimated unconventional TRR were compared with those from EIA (Energy Information Administration) and companies to support the effectiveness of basin analysis results.
Integrated Reservoir and Decision Modeling to Optimize Northern Barnett Shale Development Strategies
Authors: Gong Xinglai , McVay Duane , Bickel Eric , Montiel Luis
Published: November 2011

In shale plays, as with all reservoirs, it is desirable to achieve the optimal development strategies, particularly well spacing, as early as possible, without overdrilling. This paper documents a new technology that can aid in determining optimal development strategies in shale reservoirs. We integrate a decline-curve-based reservoir model with a decision model that incorporates uncertainty in production forecasts. Our work extends previous work by not only correlating well spacing and other completion parameters with performance indicators, but also developing an integrated model that can forecast production probabilistically and determine the impact of development decisions on long-term production.

A public data set of 64 horizontal wells in the Barnett shale play in Cooke, Montague and Wise Counties, Texas, was used to construct the integrated model. This part of the Barnett shale is in the oil window and wells produce significant volumes of hydrocarbon liquids. The data set includes directional surveys, completion and stimulation data, and oil and gas production data. Completion and stimulation parameters, such as perforated interval, fluid volume, proppant mass, and well spacing, were correlated with decline curve parameters, such as initial oil rate and a proxy for the initial decline rate, the ratio of cumulative production at 6 months to 1 month (CP6to1), using linear regression. In addition, a GOR model was developed based on thermal maturity and average GOR versus time. Thousands of oil and gas production forecasts were generated from linear regression and GOR models using Monte Carlo simulation, which serve as the input to the decision model. The decision model then determines the impact of well spacing and other completion/stimulation decisions on long-term production performance.

The technology introduced in this paper can be used to help operators in unconventional reservoirs reach optimal spacing and completion strategies earlier in the lives of these reservoirs, which could accelerate production and increase reserves.
A Triple Porosity Model for Shale Gas Reservoirs
Authors: Dehghanpour Hassan , Shirdel Mahdy
Published: November 2011

Naturally fractured shale reservoirs with multiple hydraulic fractures have been repeatedly described by dual porosity models. In these models the reservoir volume is divided into extremely low permeable shale matrix blocks surrounded by a fracture network. The low permeability of the matrix blocks limits the gas flow from matrix to the fracture. However, in many shale reservoirs unexpected high gas production has been observed which cannot be justified with the conventional dual porosity models.

Recent discoveries reveal that natural and induced micro fractures, may serve as hidden pathways for the communication between matrix and fracture network. Hence, one idea to more reliably model the gas production in shale reservoirs is incorporating micro fractures in the Dual porosity models.

In this paper, we hypothesis that the matrix blocks considered in the dual porosity model can themselves be considered a dual porosity media. We assume that the overall matrix system is composed of sub-matrices with nano Darcy permeability and micro fractures with milli to micro Darcy permeability. We assume that viscous Darcy flow is dominant in macro and micro fracture networks, and diffusion and desorption mechanisms are dominant in sub-matrices. Furthermore, we extend the existing transient and pseudo-steady-state dual porosity formulations, and develop a triple porosity model for the inner shale reservoir. We perform sensitivity analysis to the non-dimensional parameters including inter-porosity transmissivity ratios and storativity of each medium on the pressure transient behavior. We observe that the proposed model can be appropriately used to see the effect of the properties of each medium on the pressure response.
Geological Characteristics and Integrated Development Plan for Giant Naturally Fractured Basement Reservoirs
Authors: Nguyen Ngoc T. , Dang Cuong T. , Bae Wisup , Chen Zhangxin , Nguyen Anh L. , Phung Thuoc H. , Tran Phuong L. , Minh Toan N.
Published: November 2011

A great portion of the world’s oil reserves is contained in naturally fractured reservoirs. As the conventional oil and gas reservoirs have become significantly depleted whereas energy demand is sharply increases, NFRs play an important role in oil exploration and makes a large contribution toward oil and gas production worldwide. However, characterization of fractured reservoir is very complex as compared as conventional reservoirs. Lacking of experiences during production stages may quickly destroy entire reservoir. Therefore, the successful case studies as well as failure lessons should be highlighted for improving recovery efficiency in such complex reservoirs.

This paper aims to introduce two historical case studies of successful development plan for giant fractured granite basement reservoirs in Viet Nam. These reservoirs contain huge hydrocarbon resources in basement source rock and present a unique geological characterization, very high heterogeneity, high temperature and closure stress. A detailed geological understanding of the reservoir, along with a creative reservoir simulation, is needed to determine the optimal recovery method for these reservoirs. These are the keys to having a successful operation, as well as reducing uncertainties and achieving the most efficient of oilfield management.

With a large database collected from over twenty years of production period of over 215 wells, the authors developed a workflow for integrating between static and dynamic data. The geological characterization of two typical basement reservoirs was thoroughly analyzed to figure out their effect on recovery schemes. A new approach for building geological model by artificial neuron network technique was introduced, and these integrated results have been served as input data for simulation with IMEX in CMG simulator. Based on the reservoir modeling, we proposed a promising method for improving oil recovery factor by optimizing the well network locations, application of horizontal well and gaslift. From our historical experiences, the authors introduce the most appropriate method for overcoming the challenge of waterflooding operation and stimulation for fractured basement reservoirs.
An Integral Formulation Approach for Numerical Solution of Tubular Reactors Models
Authors: Hernandez-Martinez Eliseo , Alvarez-Ramirez Jose , Valdes-Parada Francisco J. , Puebla Hector
Published: November 2011

In this paper, we derive an integral formulation approach based on Green’s function for the numerical solution of tubular reactor models described by reaction-diffusion-convection (RDC) equations with Danckwerts-type boundary conditions. The integral formulation approach allows the direct incorporation of boundary conditions and leads to a stable and accurate numerical integration with smooth round-off error. Numerical simulations of two of tubular reactors models are presented in order to illustrate the numerical accuracy of the method. The results are compared with those resulting from using standard finite difference method. Our results show that the integral formulation approach improves the performance of classical FD schemes.
Enhanced Production of Menaquinone 7 via Solid Substrate Fermentation from Bacillus subtilis
Authors: Mahanama Raja , Berenjian Aydin , Valtchev Peter , Talbot Andrea , Biffin Ray , Regtop Hub , Dehghani Fariba , Kavanagh John M.
Published: November 2011

Natto, the richest known source of menaquinone 7 (MK7), is traditionally produced via Solid Substrate Fermentation (SSF) by Bacillus subtilis natto on cooked soy beans. In this work we report a threefold increase in MK7 concentration through the use of a mixture of soy protein granules and nixtamalized corn grits. The effects of fermentation processing factors were investigated and optimized in laboratory scale. These factors include initial moisture content, incubation temperature, incubation time, α-amylase pretreatment and solid substrate medium. Response surface methodology (RSM) was used to develop a mathematical model to identify the optimum values of key process variables to increase MK7 concentration; the model was also validated experimentally. The polynomial model fitted the experimental data well with R2 = 0.89 and R2 (adj) = 0.83. MK7 production was increased from 57.78 ± 1.57 mg/kg to 67.01 ± 0.18 mg/kg when the strain was cultivated at optimum conditions predicted by statistical approach (70% initial moisture, 35°C, 4 days, 10 µL/g amylase and equal substrate mix) as compared to basal conditions (60% initial moisture, 40°C, 6 days, 10 µL/g amylase and equal substrate mix).
Does Audit Fee Homogeneity Exist? Premiums and Discounts Attributable to Individual Partners
Authors: Taylor Stuart D.
Published: November 2011

This paper investigates the implied assumption, made in many audit fee determination studies, that, within a given audit firm, all partners produce a statistically identical level of audit quality and earn a statistically identical level of audit fees. This is referred to as the “homogeneity assumption.” However, this is contradicted by the individual auditor behavioral literature, which shows that different individual auditor characteristics can have an impact on audit quality. Given the fact that audit partners differ in their quality, this paper hypothesizes that different audit partners will be able to earn differing levels of fees. This hypothesis is tested by estimating an audit fee model using data from 822 Australian publicly listed companies for the year 2005. Australia is an ideal audit market for this research, as the disclosure of the name of the audit engagement partner in the audit report is mandatory. The empirical results indicate that individual audit partners earn individual audit fee premiums (or discounts) that are not explainable by the audit firms of which they are members.

Data Availability: All data have been extracted from publicly available sources.