bluuebunny/crossref_metadata_2025 huggingface dataset:
The History Textbook, Born Digital
Authors: Noonan Ellen
Published: September 2013

This essay explores how the American Social History Project's work in history education (professional development programs with K-12 and college history faculty, websites, and CD-ROMs) has developed over time. It considers the possibilities inherent in a radically rethought history textbook — grounded in research by Sam Wineburg and others into how people learn about history — to create a new model for history learning that uses digital tools to foster basic literacy, historical thinking skills, and deep understanding and inquiry into historical content.
Gerda Lerner, 1920 – 2013
Authors: Gordon Linda
Published: September 2013

This piece is an appreciation of the sources and significance of the work of Gerda Lerner, 1920 – 2013.
Event, Abyss, Excess: The Event of Women in Chinese Commercial Advertisement, 1910s-1930s
Authors: Barlow Tani E.
Published: September 2013

This essay solders together a historical case study of advertising on the China mainland in the early twentieth century with a series of generalizable appraisals and determinations to establish how the catachresis woman is evental. The event of women emerged historically in part because commercial advertising alleges that it did, and in part because at roughly the same time a subjective claim—“I am a woman”—began to be voiced. Although registered orthographically, woman 女性 is not simply a rhetorical category or a natural fact; it is not the effect of abyssal sex difference or an array of performatively accreted social subjects. It is a historical novelty. This essay universalizes a case rooted in Chinese- and Japanese-language archives and historical specificities, particularly the international advertising ephemera that presents a multiple (Badiou’s language for a set or “context”) or site where a historical event could have erupted and, in this case, did erupt. Ephemera are useful in historical analysis, as Walter Benjamin suggested a century ago, because historical events lie immanent in detritus as potential dialectical images, which the determined historian can extricate. Reading Badiou’s philosophy creatively, the essay makes the case that women or woman is an emergent, historical, modern, and universal truth; direct critique of Badiou also drives home the point that philosophy (or “theory”) is vulnerable to history and that historically, factually, actually, and in truth, women and feminism are foundations of modernity no matter how modernity is qualified.
Historicizing Gender: A Study of Chinese Women’s Liberation from 1949 to 1966
Authors: Limin Dong
Published: September 2013

This essay examines the ways a gender studies perspective has been applied in Chinese academic reflections on China’s socialist culture and practice during the so-called Seventeen-Year Period, which spanned from the founding of the People’s Republic of China in 1949 to the beginning of the Cultural Revolution in 1966 and is usually considered the most important period for the establishment of the socialist regime and political system. The essay builds on the premise that since the 1980s, gendered critiques of the Seventeen-Year Period, by applying imported gender theory, have tended to treat woman as an invisible category whose individual agency and distinct, complex subjectivities are sacrificed to the patriarchal state’s priorities and socialist ideology. As a case study for alternative ways to reflect on women’s struggles during the Mao era, the essay analyzes several stories by representative Seventeen-Year Period writer Zhao Shuli, paying special attention to the evolution of Zhao’s treatment of the relationship between women and state projects throughout the Seventeen-Year Period. Presenting a case study in literary fiction may bring attention to some of the blind spots and limitations of the current gender theory applications widely upheld by the Chinese academic world since the 1980s. This essay argues that only when socialist practice and feminist critique are put in vigorous dialogue with history can there emerge truly productive ways of understanding women’s liberation movements during the Seventeen-Year Period.
Trespassing, Crisis, and Renewal: Li Yugang and Cross-Dressing Performance
Authors: He Chengzhou
Published: September 2013

As an important representative of cross-dressing performance in Chinese popular culture, Li Yugang (李玉刚) is highly acclaimed both in and outside China for his impersonation of well-known beauties in Chinese history and literature. By interweaving Peking Opera with elements of popular culture, Li Yugang has won the recognition of both market and mainstream cultures, successfully adding a modern edge to the traditional art. Like reality television shows in the West, Li Yugang’s cross-dressing performances tend to use sensationalism to attract viewers and to increase advertising revenue, benefitting from mass media like television and the Internet, and vice versa. While a capitalist logic is at work in Li Yugang’s rise as a national and international star and icon of Chinese popular culture, his popularity may also be read positively as a symbol of liminality for progress and liberalization in present Chinese society. The cross-dressing performance transgresses the boundaries between man and woman, traditional and modern, local and global, marginal and mainstream. The crisis of categories that this trespassing entails has proven significant for cultural reform and renewal. Li Yugang’s story of transformation from grass roots to mainstream demonstrates the possibilities of success for talented and aspiring individuals. Furthermore, he should be applauded for his contribution to the internationalization of Chinese culture. Having made many successful tours in a number of countries, he has played an important role in promoting cross-cultural exchanges and understandings. From the perspective of gender theory, Li Yugang and Chinese cross-dressing performance both support and challenge the concept of gender performativity, both decontextualize and localize Western theories of transvestism.
Advancing the activity cliff concept
Authors: Hu Ye , Stumpfe Dagmar , Bajorath Jürgen
Published: September 2013

The activity cliff concept has experienced increasing interest in medicinal chemistry and chemoinformatics. Activity cliffs have originally been defined as pairs of structurally similar compounds that are active against the same target but have a large difference in potency. Activity cliffs are relevant for structure-activity relationship (SAR) analysis and compound optimization because small chemical modifications can be deduced from cliffs that result in large-magnitude changes in potency. In addition to studying activity cliffs on the basis of individual compounds series, they can be systematically identified through mining of compound activity data. This commentary aims to provide a concise yet detailed picture of our current understanding of activity cliffs. It is also meant to introduce the further refined activity cliff concept to a general audience in drug development.
Joint registries
Authors: Phillips J. R. A.
Published: September 2013

Not all questions can be answered by prospective randomised controlled trials. Registries were introduced as a way of collecting information on joint replacements at a population level. They have helped to identify failing implants and the data have also been used to monitor the performance of individual surgeons. This review aims to look at some of the less well known registries that are currently being used worldwide, including those kept on knee ligaments, ankle arthroplasty, fractures and trauma.
GH replacement causing acute hyperglycaemia and ketonuria in a type 1 diabetic patient
Authors: Cavlan Dominic , Vijayaraghavan Shanti , Gelding Susan , Drake William
Published: September 2013

A state of insulin resistance is common to the clinical conditions of both chronic growth hormone (GH) deficiency and GH excess (acromegaly). GH has a physiological role in glucose metabolism in the acute settings of fast and exercise and is the only anabolic hormone secreted in the fasting state. We report the case of a patient in whom knowledge of this aspect of GH physiology was vital to her care. A woman with well-controlled type 1 diabetes mellitus who developed hypopituitarism following the birth of her first child required GH replacement therapy. Hours after the first dose, she developed a rapid metabolic deterioration and awoke with hyperglycaemia and ketonuria. She adjusted her insulin dose accordingly, but the pattern was repeated with each subsequent increase in her dose. Acute GH-induced lipolysis results in an abundance of free fatty acids (FFA); these directly inhibit glucose uptake into muscle, and this can lead to hyperglycaemia. This glucose–fatty acid cycle was first described by Randle et al. in 1963; it is a nutrient-mediated fine control that allows oxidative muscle to switch between glucose and fatty acids as fuel, depending on their availability. We describe the mechanism in detail.

Learning points

There is a complex interplay between GH and insulin resistance: chronically, both GH excess and deficiency lead to insulin resistance, but there is also an acute mechanism that is less well appreciated by clinicians.

GH activates hormone-sensitive lipase to release FFA into the circulation; these may inhibit the uptake of glucose leading to hyperglycaemia and ketosis in the type 1 diabetic patient.

The Randle cycle, or glucose–fatty acid cycle, outlines the mechanism for this acute relationship.

Monitoring the adequacy of GH replacement in patients with type 1 diabetes is difficult, with IGF1 an unreliable marker.
Late bone metastasis from an apparently benign oncocytic follicular thyroid tumor
Authors: Boronat Mauro , Cabrera Juan J , Perera Carmen , Isla Concepción , Nóvoa Francisco J
Published: September 2013

A man underwent total thyroidectomy for goiter when he was 62 years old. The pathology report informed on a 5.5 cm oncocytic follicular adenoma and a 3.5 mm papillary microcarcinoma. Due to the papillary tumor, he was treated with ablative radioiodine therapy and suppressive doses of levothyroxine. After uneventful follow-up for 9 years, increased levels of serum thyroglobulin were detected. Further imaging studies including a whole body scan (WBS) after an empirical dose of 200 mCi 131I were negative. Two years later, a 99mTc SestaMIBI WBS and a 2-[18F]-fluoro-2-deoxy-d-glucose positron-emission tomography showed a well-delimited focal uptake in the right femur. A bone biopsy of the lesion demonstrated metastasis of follicular thyroid carcinoma. Retrospective histological reexamination of available material from the primary oncocytic thyroid tumor failed to reveal definitive traits of malignancy.

Learning points

Oncocytic follicular thyroid tumors are a relatively uncommon variant of follicular thyroid neoplasms mostly composed of distinctive large oxyphilic cells (Hürthle cells).

Criteria for the distinction between benign and malignant oncocytic neoplasms are not different from those used in the diagnosis of ordinary follicular tumors.

Some cases of apparently benign oncocytic neoplasms have been found to develop malignant behavior.

Search to rule out vascular and capsular invasion should be particularly exhaustive in histological assessment of oncocytic thyroid tumors.

Even so, long-term surveillance remains appropriate for patients with large apparently benign oncocytic tumors.
Vasculitis 2013. What are the changes introduced in the 2012 Chapel Hill Consensus Conference?
Authors: Zeher Margit
Published: September 2013

Vasculitis is a heterogeneous group of rare disorders in which inflammation of blood vessels is the common feature. Due to the increasing number of diseases as well as overlaps and gaps in the definition and nomenclature, the classification criteria were constantly changing in the past decades. The classifications were based essentially on the size of affected blood vessels and pathologic characteristics of inflamed vessel walls. The standard procedures and validated diagnostic criteria are missing from the diagnostics of vasculitis, thus in clinical practice the classification criteria are applicable. The 2012 Chapel Hill Consensus Conference brought a change in the definition, nomenclature and classification of previously uncategorized diseases. The definitions of subgroups accurately determine the diagnosis of the specific disease, and they are suitable for establishing homogeneous disease groups. By better understanding of the etiopathogenetic factors, further diseases and subgroups may be defined in the near future. Orv. Hetil., 2013, 154, 1571–1578.
Experimentally elevated levels of testosterone at independence reduce fitness in a territorial bird
Authors: Martínez-Padilla J. , Pérez-Rodríguez L. , Mougeot F. , Ludwig S. C. , Redpath S. M.
Published: September 2013

Environmental conditions and individual strategies in early life may have a profound effect on fitness. A critical moment in the life of an organism occurs when an individual reaches independence and stops receiving benefits from its relatives. Understanding the consequences of individual strategies at the time of independence requires quantification of their fitness effects. We explored this period in the Red Grouse (Lagopus lagopus scoticus). In this system, testosterone and parasite (Trichostrongylus tenuis) levels are known to influence survival and reproduction, the two key components of individual fitness. We experimentally and simultaneously manipulated testosterone and parasites at three levels (high, intermediate, and control levels for both factors) in 195 young males in five populations using a factorial experimental design. We explored the effects of our treatments on fitness by monitoring reproduction and survival throughout the life of all males and estimating λind, a rate‐sensitive index of fitness. Parasite challenges increased the number of worms with a time lag, as previously found. However, we did not find significant effects of parasite manipulations on fitness, possibly because parasite abundance did not increase to harmful levels. Our hormone manipulation was successful at increasing testosterone at three different levels. Such increases in hormone levels decreased overall fitness. This was caused by reduced offspring production in the first breeding attempt rather than by any effect of the treatment on bird survival. Our results highlight that investing in high testosterone levels at independence, a strategy that might enhance short‐term recruitment probability in territorial species such as Red Grouse, has a fitness cost, and can influence the resolution of the trade‐off between reproduction and survival later in life.
Carbon storage landscapes of lowland Hawaii: the role of native and invasive species through space and time
Authors: Hughes R. Flint , Asner Gregory P. , Mascaro Joseph , Uowolo Amanda , Baldwin James
Published: September 2013

Tropical forests are important storehouses of carbon and biodiversity. In isolated island ecosystems such as the Hawaiian Islands, relative dominance of native and nonnative tree species may influence patterns of forest carbon stocks and biodiversity. We determined aboveground carbon density (ACD) across a matrix of lava flows differing in age, texture, and vegetation composition (i.e., native or nonnative dominated) in wet lowland forests of Hawaii Island. To do this at the large scales necessary to accurately capture the inherent heterogeneity of these forests, we collected LiDAR data across areas of interest and developed relationships between LiDAR metrics and field‐based estimates of forest ACD. This approach enabled us to inventory, rather than merely sample, the entire populations (i.e., forests) of interest. Native Hawaiian wet lowland forests exhibited ACD values similar to those of intact tropical forests elsewhere. In general, ACD of these forests increased with increasing lava flow age, but patterns differed between native and nonnative forest stands. On the youngest lavas, native‐dominated forest ACD averaged <60 Mg/ha, compared to ∼100 Mg C/ha for nonnative‐dominated forests. This difference was due to the presence of the nonnative, N2‐fixing trees F. moluccana and C. equisetifolia in the nonnative‐dominated forest stands, as well as the corresponding absence of N2‐fixing trees in native‐dominated forest stands. Following ∼500 years of primary succession and thereafter, however, both forest types exhibited ACD values averaging ∼130 Mg C/ha, although it took nonnative forests only 75–80 years of post‐establishment succession to reach those values. Given the large areas of early‐successional M. polymorpha‐dominated forest on young lava flows, further spread of F. moluccana and C. equisetifolia populations would likely increase ACD stocks but would constitute a significant erosion of the invaluable contribution of Hawaii's native ecosystems to global biodiversity.
Competitive interactions modify the temperature dependence of damselfly growth rates
Authors: Nilsson-Örtman Viktor , Stoks Robby , Johansson Frank
Published: September 2013

Individual growth rates and survival are major determinants of individual fitness, population size structure, and community dynamics. The relationships between growth rate, survival, and temperature may thus be important for predicting biological responses to climate change. Although it is well known that growth rates and survival are affected by competition and predation in addition to temperature, the combined effect of these factors on growth rates, survival, and size structure has rarely been investigated simultaneously in the same ecological system. To address this question, we conducted experiments on the larvae of two species of damselflies and determined the temperature dependence of growth rate, survival, and cohort size structure under three scenarios of increasing ecological complexity: no competition, intraspecific competition, and interspecific competition. In one species, the relationship between growth rate and temperature became steeper in the presence of competitors, whereas that of survival remained unchanged. In the other species, the relationship between growth rate and temperature was unaffected by competitive interactions, but survival was greatly reduced at high temperatures in the presence of interspecific competitors. The combined effect of competitive interactions and temperature on cohort size structure differed from the effects of these factors in isolation. Together, these findings suggest that it will be challenging to scale up information from single‐species laboratory studies to the population and community level.
Native and domestic browsers and grazers reduce fuels, fire temperatures, and acacia ant mortality in an African savanna
Authors: Kimuyu Duncan M. , Sensenig Ryan L. , Riginos Corinna , Veblen Kari E. , Young Truman P.
Published: September 2013

Despite the importance of fire and herbivory in structuring savanna systems, few replicated experiments have examined the interactive effects of herbivory and fire on plant dynamics. In addition, the effects of fire on associated ant–tree mutualisms have been largely unexplored. We carried out small controlled burns in each of 18 herbivore treatment plots of the Kenya Long‐term Exclosure Experiment (KLEE), where experimentally excluding elephants has resulted in 42% greater tree densities. The KLEE design includes six different herbivore treatments that allowed us to examine how different combinations of megaherbivore wildlife, mesoherbivore wildlife, and cattle affect fire temperatures and subsequent loss of ant symbionts from Acacia trees. Before burning, we quantified herbaceous fuel loads and plant community composition. We tagged all trees, measured their height and basal diameter, and identified the resident ant species on each. We recorded weather conditions during the burns and used ceramic tiles painted with fire‐sensitive paints to estimate fire temperatures at different heights and in different microsites (under vs. between trees). Across all treatments, fire temperatures were highest at 0–50 cm off the ground and hotter in the grass under trees than in the grassy areas between trees. Plots with more trees burned hotter than plots with fewer trees, perhaps because of greater fine woody debris. Plots grazed by wildlife and by cattle prior to burning had lower herbaceous fuel loads and experienced lower burn temperatures than ungrazed plots. Many trees lost their ant colonies during the burns. Ant survivorship differed by ant species and at the plot level was positively associated with previous herbivory (and lower fire temperatures). Across all treatments, ant colonies on taller trees were more likely to survive, but even some of the tallest trees lost their ant colonies. Our study marks a significant step in understanding the mechanisms that underlie the interactions between fire and herbivory in savanna ecosystems.
The Effects of Exercise During Pregnancy: Theories, Evidence, and Interventions
Authors: Yeo SeonAe
Published: September 2013

Physical activities provide women a way to improve their health and intervene in disease processes during pregnancy. This chapter briefly describes pathophysiological models and then examines current research on the effects of physical activity on prevention and treatment of gestational diabetes and preeclampsia. The chapter then reviews cognitive behavioral theories and current literature on the effects of behavioral interventions on physical activity in pregnancy. The literature helps to explain the pathophysiological mechanisms through which physical activity mediates disease processes and the behavioral interventions through which physical activity can be introduced and sustained during pregnancy. Throughout the chapter, both pathophysiological models and behavioral theories are viewed as part of a socioecologic model that encompasses pregnancy and physical activity.
Using Function-Focused Care to Increase Physical Activity Among Older Adults
Authors: Resnick Barbara , Galik Elizabeth
Published: September 2013

Despite the known benefits of physical activity for older adults, adherence to regular physical activity recommendations is poor. Less than half of adults in this country meet physical activity recommendations with reasons for lack of adherence including such things as access, motivation, pain, fear, comorbidities, among others. To overcome these challenges, function-focused care was developed. Function-focused care is a philosophy of care that focuses on evaluating the older adult's underlying capability with regard to function and physical activity and helping him or her optimize and maintain physical function and ability and continually increase time spent in physical activity. Examples of function-focused care include such things as using verbal cues during bathing, so the older individual performs the tasks rather than the caregiver bathing the individual; walking a resident or patient to the bathroom rather than using a urinal, or taking a resident to an exercise class. There are now over 20 studies supporting the benefits of function-focused care approaches across all settings and different types of patient groups (i.e, those with mild versus moderate-to-severe cognitive impairment). The approaches for implementation of function-focused care have also been well supported and have moved beyond establishing effectiveness to considering dissemination and implementation of this approach into real world clinical settings. The process of dissemination and implementation has likewise been articulated and supported, and ongoing work needs to continue in this venue across all care settings.
Hispanic Women and Physical Activity: An Integrative Review
Authors: D'Alonzo Karen T. , Saimbert Marie K.
Published: September 2013

Hispanics/Latinos represent the largest, fastest growing, and youngest minority group in the United States. Although data suggest that most Hispanics/Latinos in the United States tend to be in better health than non-Hispanic Whites (the so-called "Hispanic Paradox"), these relative advantages in health status decrease markedly with the number of years of residence in the United States. Hispanic women or Latinas, in general, report less than recommended levels of physical activity (PA), putting them at greater risk for the development of cardiovascular disease (CVD) and other chronic illnesses associated with sedentary lifestyles.
Overweight and Obesity in Youth With Type 1 Diabetes
Authors: Minges Karl E. , Whittemore Robin , Grey Margaret
Published: September 2013

Overweight and obesity in youth with type 1 diabetes (T1D) is now prevalent and accounts for significant health consequences, including cardiovascular complications and dual diagnosis of type 2 diabetes. Physical activity and lifestyle are modifiable and play an important role in the prevention and management of excessive weight, but it is unclear how these factors relate to overweight and obese youth with T1D. Thus, a systematic review was conducted to examine how physical activity, sedentary behavior, sleep, and diet are related to overweight/obesity in youth with T1D. Seven observational and intervention studies published between 1990 and 2013 were included in the review. Prevalence of overweight ranged from 12.5% to 33.3%. Overweight in youth with T1D was associated with infrequent napping, increased screen time, and skipping breakfast and dinner but was not related to time engaged in physical activity. Weight-related interventions indicated modest weight loss along with improved glycemic control. In light of this review, there is a need for high quality research that examines all levels of activity in youth with T1D to identify lifestyle modification targets for weight prevention and management.
New Water Depth Record for Electric Line Operations, Retrieving Asphaltenes with Riserless Light Well Intervention
Authors: Ashcraft Steven , Karlsen Ole Eddie , Luviano Angel , Morrison Bevan
Published: September 2013

Capabilities in the industry have been expanded on a recent operation performed in the Gulf of Mexico, where a new electric line (e-line) water depth record was set in addition to demonstrating that asphaltenes can be removed on e-line with Riserless Light Well Intervention (RLWI).

The operator had planned to set a removable hold open sleeve with a subsurface-controlled PB valve across a failed surface controlled subsurface safety valve (SCSSV) on one of their subsea wells. The well had not been re-entered since production start-up, which meant that the downhole conditions were unknown. During the slickline gauge run, the toolstring hung up after only 581 ft in the well and could not be jarred any deeper. After a failed attempt to chemically remediate the blockage, the client decided to try e-line milling, consisting of an e-line tractor for conveyance and a cleaning tool fitted with a reverse circulating bit to mill through the obstruction and capture any debris. This toolstring was initially set down in the production tubing at 4,083 ft ELM and was picked-up to 4,000 ft ELM. At this depth the cleaning tool was engaged and was able to mill at 10 fph past the previous hang up depth (HUD) of the slickline gauge. We continued downhole another 1,217 ft where an obstruction was encountered at 5,778 ft ELM and the toolstring became stuck. The toolstring was worked free and brought to the surface where it was established that the bit was packed with solid debris and the bailer sections were full of dense, hard-packed asphaltenes. The operator concluded that this very dense material would continue all the way down the well and decided that it was would not be feasible to continue milling as there were almost certain, terminal sticking risks.

Based on the samples recovered, the operator was able to avoid unnecessary costs incurred from attempting to work further downhole under these conditions. They decided to suspend operations until they had fully analyzed the samples and could make an informed decision on how best to remove the asphaltenes. This paper will discuss job planning, operations, and lessons learned.
Experimental and Numerical Analysis of Gas Transport in Shale Including the Role of Sorption
Authors: Alnoaimi K. R. , Kovscek A. R.
Published: September 2013

This study adds to the knowledge base of carbon dioxide sequestration and methane recovery enhancement from gas shale. If gas shale is desired to be used as a storage medium for CO2, then knowledge of how to maintain gas permeability while enhancing storage via sorption is mandatory. In this work, physical and numerical pressure-transient, pulse-decay experiments are conducted on Eagle Ford shale cores. The experiments are conducted isothermally at various pore and confining pressures that maintain a constant net effective stress. The gases investigated are helium, methane, and carbon dioxide. Porosity and permeability measurements are conducted using various techniques including numerical simulation that incorporates detailed measurements of the in-situ, core-scale porosity distribution. The research simulator is fully implicit, finite volume, unconditionally stable, and incorporates gas sorption in ultra-small pore networks. Langmuir sorption parameters are determined after matching the upstream and downstream pressure profiles simultaneously. Experiments are also interpreted using available analytical models and compared to the high-resolution simulations matched to experimental observations. Results highlight the interplay of gas slip and sorption of pure gases at core-level. Results also quantify the role of CO2 sorption in various shale fabrics and thus promote the potential for sequestration. While the gas molecular kinematic diameter plays a role in dictating the pore accessibility, and thus governs slip flow, gas sorption is more influential in determining permeability. Gas transport in wide channels, however, undermines the influence of sorption on measured permeability. While He is a non-sorptive gas, CH4 sorption isotherms are described by a Langmuir model and CO2 isotherms are similar to an n-BET model. The experiments demonstrate that He and CH4 have a similar measured permeability while carbon dioxide has a lower permeability. These differences are attributed to the strong sorption of carbon dioxide.
Optimized Well Modeling of Liquid-Rich Shale Reservoirs
Authors: Juell Aleksander Oma , Whitson Curtis Hays
Published: September 2013

This paper presents an integrated modeling approach for history matching and economic optimization of wells producing from liquid-rich shale reservoirs (LRSR). History matching uses daily pressures and gas-oil-water production data to estimate average parameters in a 2D/3D finite-difference (FD) horizontal multi-fractured well model: rock permeability, fracture half-length, relative permeabilities, and in-situ fluid (solution gas-oil ratio). Economic-based well design uses the same FD model to maximize net present value (NPV) by finding optimal well completion parameters: number of fractures, and fracture size. Revenue optimization (short-term and long-term) is performed with the same FD well model by finding the drawdown that maximizes revenue. For undersaturated gas condensate LRSR wells, optimal drawdown is often equal to or somewhat below the reservoir dewpoint pressure. We study optimal drawdown control for new wells that are optimized from start of production, and for wells that are optimized only after some initial period of sub-optimal drawdown control. We also compare short-term versus long-term economic optimization strategies.

We provide examples that clearly show the potential for improved economic development of LRSR using optimized well design and drawdown control, for new and existing wells. Our study shows a significant economic upside to proper selection of completion design, and for undersaturated gas condensate wells, optimal drawdown has significant potential to increase daily revenues.
Streamline-Based Time Lapse Seismic Data Integration Incorporating Pressure and Saturation Effects
Authors: Watanabe Shingo , Han Jichao , Datta-Gupta Akhil , King Michael J.
Published: September 2013

We present an efficient history matching approach that simultaneously integrates 4-D repeat seismic surveys with well production data. This approach is particularly well-suited for the calibration of the reservoir properties of high-resolution geologic models because the seismic data is areally dense but sparse in time, while the production data is continuous in time but averaged over interwell spacing. The joint history matching is performed using streamline-based sensitivities derived from either finite-difference or streamline-based flow simulation. Previous approaches to seismic data integration have mostly incorporated saturation effects but the pressure effects have largely been ignored. We propose, for the first time, streamline-based analytic approaches to compute parameter sensitivities that relate the seismic data to reservoir properties while accounting for both pressure and saturation effects via appropriate rock physics models. The inverted seismic data (e.g., changes in acoustic impedance or fluid saturations), is distributed as a 3-D high-resolution grid cell property or as a vertically integrated two-dimensional map. We derive pressure drop sensitivities along streamlines in addition to our previous work of water saturation sensitivity computation. The novelty of the method lies in the analytic sensitivity computations which make it computationally efficient for high resolution geologic models. We demonstrate the versatility of our approach by implementing it in a finite difference simulator which incorporates detailed physical processes, while the streamline trajectories provide for rapid evaluation of the sensitivities. The efficacy of our proposed approach is demonstrated with both synthetic and field applications. The synthetic example is the SPE benchmark Brugge field case. The field example involves waterflooding of a North Sea reservoir with multiple seismic surveys. For both the synthetic and the field cases, the advantages of incorporating the time-lapse variations are clearly demonstrated through improved estimation of the permeability distribution, pressure profile, and fluid saturation evolution and swept volumes.
Potential of Improved Waterflooding in Acid-Hydraulically-Fractured Shale Formations
Authors: Morsy Samiha , Sheng J. J , Gomaa Ahmed , Soliman M. Y
Published: September 2013

Water flooding is the economical secondary recovery method that has been used for more than seventy years in conventional oil reservoirs. However, few studies focused on water flooding viability in unconventional shale formations. The objective of this study is to improve the performance of waterflooding in shale formations by enhancing spontaneous imbibition through optimizing hydraulic fracturing fluid and fracture orientation. Core samples of Eagle Ford, Mancos, Barnett, and Marcellus shales were used in this study. Fractures were generated by cutting the core samples into two halves; some are along bedding planes and others across bedding planes. Shales usually have natural micro-fractures, (e.g. Eagle Ford Shale) and acid may enhance micro-fracture conductivity, so we want to investigate the impact of using low concentrations of HCl in the hydraulic fracturing process on spontaneous imbibition. Some of the samples were immersed in different HCl solutions to create etched fractures. We measured the porosity and the oil recovery in both the acid-treated and non-treated samples during spontaneous water imbibition for the samples with different fracture orientation. The mechanical properties of the acid-treated and non-treated samples were measured using different acid concentrations (1-3 wt%) at 200°F. The samples were 2.54 and 3.81 cm in diameter and 2.54 to 5.08 cm in length. The measured porosities were 1-3% for the non-treated samples and 1.3-10.5% for the treated samples. We observed that the oil recovery factors of the spontaneous imbibition for the samples treated with acid were 47% from Eagle Ford, 53% from Mancos, 28% from Barnett, and 38% from Marcellus. The recovery factors from the non-treated samples were 12% from Eagle Ford, 4% from Mancos, 13% from Barnett, and 3% from Marcellus. Furthermore, we observed that fracture orientation affects spontaneous imbibition in all of the studied rock formations, especially for Marcellus shale formation where the recovery factors varied from 4% for the samples cut across bedding planes to 38% for the samples cut along bedding planes. Eagle Ford samples showed the greatest reduction in Young's Modulus ranging from 25-82% when exposed to 1-3 wt% HCl solutions and 75% when exposed only to 5 wt% NaCl saline solution at 200°F. Our results showed that imbibition in unconventional shale oil formations could be improved by using low pH fracturing fluids and optimization of fracturing orientation.
Estimating Reservoir Composition for Gas Condensates and Volatile Oils from Field Data
Authors: Spivey John P. , McCain W. D.
Published: September 2013

This work describes a method for estimating reservoir fluid composition for gas condensates and volatile oils from readily available field data. Required data are separator conditions; first stage separator gas specific gravity, non-hydrocarbon impurities content, and gas-liquid ratio; and stock tank API gravity. The well must be stabilized, and the flowing bottomhole pressure must be above the saturation pressure.

A database comprising compositions for 23 wet gases, 33 gas condensates, and 19 volatile oils was taken from the literature. The data sets included compositions in mole fractions of methane through heptanes-plus and nonhydrocarbon impurities, along with molecular weight and specific gravity of the heptanes-plus fraction. The database was restricted to fluids with heptanes-plus content between 1 and 25 mole %, and with relatively low non-hydrocarbon impurities content (less than 4 mole % H2S, less than 6 mole % CO2, less than 11 mole % N2, and less than 18 mole % total nonhydrocarbons).

The method predicts reservoir fluid composition through heptanes-plus along with molecular weight and specific gravity of the heptanes-plus fraction. The resulting reservoir fluid composition may be used with an untuned equation of state to obtain preliminary estimates of saturation pressure, maximum liquid dropout, and modified-black-oil (MBO) fluid property tables for simulation. The predicted composition may also be used as a cross check of laboratory-measured composition.

The method has been tested on data sets for 16 gas condensates that were not part of the composition database. Predicted compositions were surprisingly accurate, with average absolute errors (AAE) for methane, 1.0 mole %; ethane, 1.2 mole %; propane, 0.7 mole %; butanes, 0.5 mole %; pentanes, 0.3 mole %; hexanes, 0.3 mole %, and heptanes-plus, 0.4 mole %. Predicted specific gravities and molecular weights of the heptanes-plus fraction had average absolute relative errors (AARE) of 1.3% and 9.7%, respectively. Saturation pressures calculated from the predicted gas-condensate compositions using an untuned equation of state had an average relative error (ARE) of −0.3% and an AARE of 6.9%, with a median relative error of -3.7% and a median absolute relative error of 4.5%.

Because of the current commercial importance of liquids-rich gas plays, the method should find application for 1) obtaining preliminary estimates of composition before laboratory data are available, 2) estimating PVT properties such as saturation pressure, maximum liquid dropout, and MBO fluid property tables from field data when PVT measurements are not available, and 3) cross-checking laboratory-measured compositions.
Effect of Wall Wettability on the Onset of Churning in Upward Gas-Liquid Annular Flow
Authors: Belfroid S. P. , Khosla V. , Nennie E. D , Alberts G. J. , Veeken C. A.
Published: September 2013

The influence of hydrophobic and hydrophilic tube walls on the pressure drop and liquid loading behavior was investigated in previous projects in the past. In this paper, results of visualization experiments and of experiments at different liquid-to-gas ratios and inclination angles are presented for hydrophobic tube walls. Experiments were performed in coated and uncoated steel and Perspex pipes of different diameters: 20 mm and 50 mm. Experiments with different deviation angles ranging from 0° (vertical) to close to horizontal (≈80°) were performed for the 20mm diameter tube. The impact of the wall wettability on the flow patterns was examined by performing flow visualizations with a high speed camera in coated and uncoated Perspex tubes. From the experiments it becomes clear that the hydrophobic coating prevents the formation of a liquid film on the tube wall. As a result, the transport of the liquid phase is solely in the form of droplets/ligaments. In the hydrophobic coated tube, the onset of churning is at a lower gas velocity than in the uncoated tube. The presence of the coating reduces the critical gas rate corresponding to the minimum pressure drop by as much as 40%. This decrease reduces for high liquid rates and for larger inclination angles. However, for a liquid content of LGR = 1000 Sm3/106 Sm3, the benefit is still 33% at a vertical flow and a reduction in the critical rate remains up to a deviation angle of 80°. The hydrophobic coating increases the friction at higher gas rate but reduces the hydrostatic head at lower gas rate with a 70% reduction at low liquid content.
Time-Delayed Fracturing: A New Strategy in Multi-Stage, Multi-Well Pad Fracturing
Authors: Manchanda Ripudaman , Sharma Mukul M.
Published: September 2013

The creation of a hydraulic fracture changes the stress distribution in the vicinity of the fracture. This stress shadow can influence the growth of subsequent fractures. Immediately after a hydraulic fracture treatment is pumped, the width of the propped fracture and the associated induced unpropped (IU) fracture network is at its maximum. The hydraulic fracture and the induced unpropped fractures close as a result of fluid leak-off over time. This implies that the stress shadow in their vicinity also decreases over time. Complete closure of induced, unpropped fractures can significantly reduce the stress shadow and make subsequent fracture stages less susceptible to fracture interference and more efficient by avoiding wastage of fluid / proppant into preexisiting fractures. This suggests that increasing the time between successive fractures in a wellbore will lead to improved fracture performance.

Using geomechanical computations we show that waiting for longer times between successive stages of a horizontal well allows for a reduction in the stress shadow and less fracture interference leading to a more efficient fracture network by successive fractures in a horizontal well. We, therefore, propose the idea of establishing a minimum time between successive fracture stages in a well. The time required for the induced un-propped fractures to close can be calculated from our models and varies based on the reservoir and fluid properties but is of the order of hours.

This controlled time-delay in fracturing can be achieved in several ways, without wasting valuable rig time in the field. We suggest several alternate innovative strategies to achieve this on the field. For example, two-well or multi-well zipper fracs can be pumped, hence increasing the time between fractures in a given well substantially (by several hours). Alternatively, in the Texas Two Step method it would be better to pump the fractures in the sequence 1, 3, 5, 2, 4 than the sequence 1, 3, 2, 5, 4 where the numbers represent the sequence of the fractures along a well starting at the toe. We propose several other fracturing sequences for multi-well pad fracturing applications and suggest how the impact of a multi-stage, multi-well pad fracturing treatment can be enhanced while conserving the time and resources used.
Psychological Care, Patient Education, Orthotics, Ergonomics and Prevention Strategies for Neck Pain: An Systematic Overview Update as Part of the ICON§ Project
Authors: Gross Anita R. , Kaplan Faith , Huang Stacey , Khan Mahweesh , Santaguida P. Lina , Carlesso Lisa C. , MacDermid Joy C. , Walton David M. , Kenardy Justin , Söderlund Anne , Verhagen Arianne , Hartvigsen Jan
Published: September 2013

Objectives:

To conduct an overview on psychological interventions, orthoses, patient education, ergonomics, and 1⁰/2⁰ neck pain prevention for adults with acute-chronic neck pain.

Search Strategy:

Computerized databases and grey literature were searched (2006-2012).

Selection Criteria:

Systematic reviews of randomized controlled trials (RCTs) on pain, function/disability, global perceived effect, quality-of-life and patient satisfaction were retrieved.

Data Collection & Analysis:

Two independent authors selected articles, assessed risk of bias using AMSTAR tool and extracted data. The GRADE tool was used to evaluate the body of evidence and an external panel to provide critical review.

Main Results:

We retrieved 30 reviews (5-9 AMSTAR score) reporting on 75 RCTs with the following moderate GRADE evidence. For acute whiplash associated disorder (WAD), an education video in emergency rooms (1RCT, 405participants] favoured pain reduction at long-term follow-up thus helping 1 in 23 people [Standard Mean Difference: -0.44(95%CI: -0.66 to -0.23)). Use of a soft collar (2RCTs, 1278participants) was not beneficial in the long-term. For chronic neck pain, a mind-body intervention (2RCTs, 1 meta-analysis, 191participants) improved short-term pain/function in 1 of 4 or 6 participants. In workers, 2-minutes of daily scapula-thoracic endurance training (1RCT, 127participants) over 10 weeks was beneficial in 1 of 4 participants. A number of psychosocial interventions, workplace interventions, collar use and self-management educational strategies were not beneficial.

Reviewers' Conclusions:

Moderate evidence exists for quantifying beneficial and non-beneficial effects of a limited number of interventions for acute WAD and chronic neck pain. Larger trials with more rigorous controls need to target promising interventions
An evaluation of keyword, string similarity and very shallow syntactic matching for a university admissions processing infobot
Authors: Hancox Peter , Polatidis Nikolaos
Published: September 2013

?Infobots? are small-scale natural language question answering systems
drawing inspiration from ELIZA-type systems. Their key distinguishing feature
is the extraction of meaning from users? queries without the use of syntactic
or semantic representations. Three approaches to identifying the users?
intended meanings were investigated: keyword based systems, Jaro-based string
similarity algorithms and matching based on very shallow syntactic analysis.
These were measured against a corpus of queries contributed by users of
aWWW-hosted infobot for responding to questions about applications to MSc
courses. The most effective system was Jaro with stemmed input (78.57%). It
also was able to process ungrammatical input and offer scalability.