bluuebunny/crossref_metadata_2025 huggingface dataset:
Uncertainty Assessment of Stimulation Design—Bakken Case Study
Authors: Jabbari H. , Ostadhassan M. , Khavanin M. , Lentz N. , Johnson S.
Published: October 2014

Numerical simulation models that are used for well stimulation planning are usually complex and are prone to error. These models have many factors that generally contain uncertainty which, in turn, lead to uncertainty in the model outputs. Uncertainty assessment (UA) can describe such uncertainties in the modeling results. It is always important to the future development plans that uncertainty be properly assessed.

This paper presents an approach to the uncertainty assessment of simulation models used for the design optimization of hydraulic fracturing. The use of numerical simulation in petroleum engineering, and the presence of uncertainty in all aspects of design and modeling, may lead to questions such as: What confidence do we have in model results? What are the limits in terms of applicability of model results? Uncertainty assessment together with sensitivity analysis can provide the answers to such questions. The Monte Carlo simulation is employed for implementing such analyses that includes repeated random sampling from input probability distributions.

In the assessment of uncertainty conducted for the Bakken case study discussed in this paper, the following seven-step procedure is implemented: describing assessment goals, describing assumptions and constraints, describing parameters and outputs, classifying factor uncertainty, conducting the sensitivity analysis, conducting the uncertainty assessment, and presenting the results with probability curves. The main goal of this study is to present the use of probabilistic modeling for assessing the uncertainties in the simulation of hydraulic fracturing and reservoir performance. Such probabilistic modeling can also help us to develop proxy models for approximating outputs at un-simulated points and to demonstrate the simulation results with probability distribution curves.
An Economic Evaluation on the Re-fracturing Treatment of the U.S. Shale Gas Resources
Authors: Eshkalak Mohammad O. , Aybar Umut , Sepehrnoori Kamy
Published: October 2014

We investigate the economic feasibility of the re-fracturing treatment of horizontal wells producing gas from unconventional reservoirs. As a result of advancements in horizontal completions and hydraulic fracturing, the U.S. has been able to economically develop several decades of worth of natural gas from shale deposits. However, a considerable concern has risen on the economic viability of shale gas development with the reasons associated to the very fast production declines as well as recent down-turns of natural gas prices beside the raise in additional costs of new technologies. Therefore, an economic analysis required to investigate the profitability of the secondary enhanced gas recovery method, re-fracturing treatment of unconventional gas resources within the U.S.

Net present value (NPV) of cash flows and internal rate of return (IRR) are calculated for different assumed gas prices considering 20 years of natural gas production from a typical unconventional reservoir. A systematic comparison is made for three scenarios, 1) re-fracturing vs. no re-fracturing (the base case scenario) 2) combination of re-fracturing and drilling new well; and 3) time-dependent re-fracturing treatment. This paper incorporated the cost of re-fracturing treatment, the cost of drilling a new horizontal well, the water treatment cost, as well as the current and future price of natural gas in the model. Findings of this work can be used to optimally develop the U.S. shale gas assets. Moreover, operators can have access to an assessment to ensure the economic success of their unconventional horizontal wells in their future re-fracturing treatments.
Dynamics of Production Decline from Shale Gas Reservoirs: Mechanistic or Empirical Models?
Authors: Mishra Srikanta , Kelley Mark , Makwana Kishan
Published: October 2014

Application of decline curve analysis in shale gas reservoirs is known to produce reserve estimates that are unphysical and/or unrealistic. It has been suggested that the assumptions inherent to these models may not always be valid in shale gas wells. For example, the boundary dominated flow period that leads to exponential decline may take years to develop in unconventional gas fields. Also, the impact of matrix adsorption/desorption processes on decline curve model parameters has not been fully investigated. To this end, we use a numerical simulator to understand key factors affecting production decline in shale gas reservoirs, and examine the appropriateness of decline curve based forecasting to model long-term flow behavior.

A numerical model was constructed to simulate production from a horizontal well in a hydraulically fractured shale reservoir. Parameters varied in the evaluation include: (a) reservoir properties, (b) hydraulic fracture properties, (c) well properties, and (d) operational parameters. Ranges in values considered for the model parameters were obtained from published data on major shale-gas plays. Simulated gas production rate time histories were evaluated using standard decline curve analysis techniques.

Our results indicate that long-term production estimates are most sensitive to hydraulic fracture and well characteristics, average pressure and permeability in the stimulated reservoir volume, and to a lesser degree on matrix flow and adsorption processes. Fitted decline curve model parameters generally exhibit time dependence, which affects the accuracy of ultimate recovery estimates with limited production data. The findings from this study suggest that although decline curve based reserve estimates may be appropriate under some conditions, it would be useful to apply a mechanistic (physics based) model for history matching production data and verify the results of decline curve analysis.
Eco-Friendly Biodegradable Materials For Zonal Isolation Of Multiple Perforation Clusters During Refracturing Of a Horizontal Well: Case History From Marcellus Shale Hydraulic Fracturing
Authors: Arnold David , Boulis Anastasios , Fragachan Francisco
Published: October 2014

For some time now the industry has been concentrating on horizontal wells in shale formations which require multi-stage fracturing operations to tap their production potential. Several different techniques have been developed for performing these operations each with their own advantages and drawbacks; however, when it comes to performing re-fracs the isolation of zones to be treated presents some major problems in logistics and operating costs no matter the initial fracturing operation method used.

A key characteristic in unconventional reservoirs development is that they need massive hydraulic fracturing to create high permeability conduits to connect the reservoir to the wellbore and assure appropriate flow rates to make the development economical. In general, production performance for this type of reservoirs show an early high inflow followed by a steep decline. Refracture jobs have been a common practice to mitigate the flow rate decline and revitalize wells productivity. In the cases where infill refracturing is used, the isolation of the existing perforations is imperative, to mitigate the loss of fluids during the refracturing process.

One approach involves the use of mechanical diverters, such as perforation balls, rock salts etc., which may be useful for one stage; however, cessation of pumping operations results in them falling out of the perforations or dissolving. In this paper, a new approach is presented using degradable materials. These materials can be tailored to plug perforations on a temporary basis but degrade over time, depending on formation temperature, to re-open them. This method has applications in initial fracturing operations as an alternative to the often used "plug and perf." method and can be extremely advantageous in refracturing operations in plugging off the existing, productive perforations and exposing the unproductive ones for treatment. It also provides similar advantages in wells with existing perforations, where additional perforations are added and need to be treated.

Moreover, a case study is used to show the application of these degradable materials in a refracturing job in a shale gas well in the Marcellus Shale. Based on the results, the sealing agents successfully bridged off the existing perforations, diverting the refracturing fluid to the new clusters. In this paper the author will discuss the evolution of fracturing methods and describe the development of degradable materials which can degrade over time for a range of bottom hole temperatures. He will continue to present a case study of its' use in a refracturing treatment in a well with 26 sets of existing perforations and 24 sets of recently perforated clusters, with the intent to seal the older clusters and begin accessing the new clusters.
Unique System for Underbalanced Drilling Using Air in the Marcellus Shale
Authors: Maranuk Chris , Rodriguez Ali , Trapasso Joe , Watson Joshua
Published: October 2014

Underbalanced drilling offers significant advantages in terms of increased rate of penetration (ROP), less formation damage, reduced lost circulation material, decreased cost of cuttings disposal, and increased production. Underbalanced drilling injects gas into a mud column to lower the overall equivalent mud weight to create a drilling environment where the pressure in the wellbore is kept lower than the fluid pressure in the formation being drilled. Air is the ultimate underbalanced fluid, but diminishes the efficiencies of mud motors, and prevents the use of mud pulse telemetry MWD tools due to the lack of an incompressible fluid. With air drilling, the only fluid injected into the well is a small amount of oil needed to prevent corrosion. Downhole mechanical forces are usually more violent due to the lack of a fluid column for dampening as well as the higher air volumes going through the bottom hole assembly (BHA) for cuttings flow. Common drilling technologies to address air drilling include Electromagnetic Telemetry (EM), mud motors, and downhole air hammers, but reliability issues are particularly prevalent, especially for the EM MWD tools and downhole mud motors.

Air drilling has become popular especially in the Marcellus and Utica shale reservoirs in the Northeast United States because of higher ROP and less formation damage. As an example, of the 111 rigs drilling in the Marcellus Shale, 27 rigs are drilling underbalanced and 23 are being drilled with air. A unique drilling system incorporating the use of downhole mud motors, EM MWD, and air hammers has been specifically designed and ruggedized to address downhole shock and vibration encountered in air drilling. Use of this system has resulted in significant reduction of non-productive time (NPT) while drilling with air.

This paper will describe how air drilling is being successfully utilized in the unconventional reservoir of the Marcellus shale in the Northeast United States. Drilling fluids and their affect on various pressure regimes will be discussed. The new drilling system will be described and drilling parameters highlighting the differences between mud and air drilling will be provided. Modifications to the BHA to increase reliability will be discussed, and success metrics presented.
Friction Reducers Fresh Rheological Insights Married to Performance
Authors: Aften Carl W.
Published: October 2014

Rheological experiments have been conducted with commercial and experimental friction reducers indicating certain profiles are advantageous for performance. In these profiles the factors of time and concentration are important in predicting the maximum performance window. These windows become apparent without the use of sophisticated rheological instrumentation.

The viscosity profile of a friction reducer is dependent on factors such as polymer charge, charge distribution, molecular weight, polymer concentration, solvent properties, specific shear rate and time. Often it is difficult to measure properties such as molecular weight and viscosity, both quite sensitive to the specific test method and many assumptions are made. In this study, the viscosity of the system depends on the shear history, concentration, and time of measurement. Most traditional viscosity methods assume a thermodynamic definition of polymer configuration. This assumption is valid for measurement of friction reduction after significant duration. However, in a hydraulic fracture, this time may not be realized during the volumetric transfer of the fluid from the pumps to the perforations. In a recirculating friction loop measurement, the friction reduction performance of an ideal candidate rapidly increases and then sometimes diminishes with recirculation time. A possible correspondence between this phenomenon can be linked to the measurement conducted in this study.

Shear rate sweeps were conducted on a variety of synthetic polymers with a Couette rheometer and a microchip rheometer. Variables studied were polymer type, concentration, shear history, time, solvent, make-down procedure, and atmosphere. Both inverse emulsion and dry friction reducers were studied. Friction reduction was measured on a once through system.

From this study, ideal friction reducer candidates can be selected by simply and rapidly examining the rheological profile and rheological nuances realized when conducting the measurements. When choosing an ideal friction reducer, it must perform rapidly and maintain the necessary friction reduction required for the time frame needed.
Improving Drilling Performance through Deployment of 12-Project Management Critical Success Factors: An Empirical Investigation
Authors: Alagba Tonye J.
Published: October 2014

Oil and gas drilling projects are the primary means by which oil companies recover large volumes of commercially available hydrocarbons from deep reservoirs. These types of projects are complex in nature, involving management of multiple stakeholder interfaces, multidisciplinary personnel, complex contractor relationships, and turbulent environmental and market conditions, necessitating the application of proven project management best practices and critical success factors (CSFs) to achieve success. Whereas there is a CSF approach to managing complex projects in construction, manufacturing, and even R&D, there is no empirically verified project management CSF approach to implementing (complex) oil and gas drilling projects. Additionally, the literature has reported alarming rates of oil and gas drilling project failure, which is attributable not to technical factors but to failure of project management. The aim of this two-part quantitative correlational study therefore, was to discover an empirically verified list of project management CSFs, which consistent application leads to successful implementation of drilling projects. The study collected survey data online, from two randomly derived samples of oil and gas drilling personnel: Members of LinkedIn's online community "Drilling Supervisors, Managers, and Engineers". A total of 219 Drilling Personnel (Drilling Engineers/Superintendents, Drilling Supervisors, and Drilling Managers) participated in the study, including 127 partcipants in the initial study and 92 in the follow-up study. The results of the study indicated that 12 project management critical success factors are individually related to success of oil and gas drilling projects. These 12 project management CSFs, are namely; Clarity of project goals & objectives, Top management support, Front-end project planning, Integrated stakeholder & supplier management, High caliber project personnel/Project team integration, Use of appropriate tools & technology, Integrated change control, Shared success criteria, Iterative monitoring & control, Communication, Use of realistic estimates, and Iterative risk management. In addition, the study found that the relationship between the 12 CSFs and drilling project success is unaffected by, and generalizable beyond participant and project demographics, namely; role designation of project personnel, project location, and project type (onshore or offshore). The significance of these findings is both practical, and theoretical. Practically, application of an empirically verified CSFs list to oil and gas drilling projects could help oil companies improve the performance of their drilling projects. Theoretically, the study's findings have helped to bridge a gap in the project management CSFs literature, and added to the general project management body of knowledge.
Use of Natural Tracer Data in Well Placement Optimization
Authors: Hutahaean Junko
Published: October 2014

Determining an optimal location and configuration of well to be drilled is a critical reservoir development decisions as it can cost millions of dollars and determine the volume of hydrocarbons being produced. This is a very challenging task due to large number of decision variables involved. One important factor to consider in field development is scale deposition. It can cause production problem and reduce hydrocarbons recovered. In the extreme case, it can cause a production well to be abandoned as a result of formation damage in the near wellbore or narrowing of the production tubing. Due to the potential high cost of scale management, scale risk deposition would be an important issue.

The aim of the paper is to optimize the placement of new wells in a field development accounting for the risk of sulphate scale deposition. This scale is formed when sulphate rich seawater, usually used as injection fluid to maintain reservoir pressure, mixes with barium rich formation brines. Multi-Objective Optimization (MOO) is used to find a range of solutions by maximizing oil recovery and minimizing scale risk. Scale risk deposition is modelled by tracking the injected seawater concentration, which acts as a natural tracer, in the produced water from each well. Penalty parameter is introduced in the optimization workflow and quantified by relating the scale risk impact in the reservoir production to scale treatment (bullhead-squeeze) as the mitigation. The study used a modified version of the benchmark reservoir model, PUNQ-S3; the model was adapted to be developed using seawater flooding, and as a result sulphate scale deposition is of a major concern. Particle Swarm Optimization (PSO), a stochastic population-based and gradient-free optimization algorithm, is applied to search over the new well locations and their completion zones in the presence of potential scale deposition risk.

The paper compares a conventional field optimization with objective only to maximize oil production to the one with accounting scale risk as extra information. The paper demonstrates that multi-objective optimization allows us to identify well locations and completion zones with high recovery and yet low scale risk, leading to significant economic benefit in a number of field development scenarios.
Simulation of Shale Mechanical Properties in PFC2d and Calibration of Them Against Lab Results for Tensile, Uni-axial and Confined Compression Tests
Authors: Fatahi Hassan
Published: October 2014

Shale oil and gas reserves became an important source of energy and their development can increase fossil fuel source. The shale exploration activities have been growing very fast worldwide. However, shale oil and gas production differs from conventional reservoirs in many ways due to its underlying complexities associated with reservoir rock and petro-physical properties as well as extremely low permeability. While massive hydraulic fracturing through horizontal well completion for commercial production of shale oil and gas is paramount, there are many development challenges in regards to understanding of hydraulic fracture propagation behaviour, and its potential impact on fluid flow as required to accurately assess the production performance. The principle mechanism of hydraulic fracture propagation behaviours in shale formation is not well documented. In addition the shale formation is very heterogonous in nature, especially in vertical direction.

The fracture propagation behaviour of rock strongly depends on rock mechanical properties, far field stress state and orientation and anisotropies present in the formations such as bedding.

This paper presents results of numerical simulation, where shale rock samples are subjected to tensile, uni-axial compression and confined compression tests; and their behaviour are studied. In the first stage, mechanical properties of the simulated samples are calibrated against mechanical properties of two oil shales considered from western US to get micro-mechanical properties that define the samples in the PFC2D. In the second stage these micro-mechanical properties are used to simulate two kinds of rock, one of which has a vertical heterogeneity and the other has lateral heterogeneity to study the effect of fissility on mechanical properties measured in different directions.
Pore-Network Modeling of Carbonate Acidization
Authors: Tansey Joseph
Published: October 2014

Carbonate reservoirs represent a significant portion of global hydrocarbon reserves. Injecting strong acids around the wellbore of carbonate wells can significantly increase near-wellbore permeability. A pore-network model is developed to capture permeability response of carbonates to acid stimulation. A novel pore-scale mass-transfer coefficient and pore-merging criterion are developed using finite element simulations. Preliminary results are able to reproduce the expected trends in permeability increase and capture the gamut of different dissolution regimes. Future work will focus primarily on using advanced subdomain coupling techniques to simulate much larger domain sizes to investigate the effects of domain size and determine a representative elementary volume.
NMR Investigation of Pore Structure in Gas Shales
Authors: Gannaway Gregory
Published: October 2014

In shales, the wettability contrast between water wet pores located between clay particles, oil wet organic pores and mixed wettability pores located at the interface between clays and organic matter, can be exploited to quantify the porosity associated with each pore system.

In order to quantify the different types of porosity, the NMR T2 spectra of 5 Barnett shale samples have been acquired, both in their native state, after dodecane saturation at 3000 psia, and after immersion in a 65% MnCl2 aqueous solution. These NMR spectra were acquired with Tau = 57 μsec on a 2MHz instrument. 65% MnCl2 aqueous solution has been found to exhibit no NMR signal and it does not mix with dodecane.

All the samples displayed a unimodal T2 distribution in their native state with a peak around 0.2 ms. This NMR peak is generally associated with clay pores. After dodecane saturation the development of a second peak around 5 ms forms. These two NMR peaks decreased after immersion in the MnCl2 solution. MnCl2 imbibition decreases the NMR water signal as it diffuses into the existing water in clay-dominated pores, and decreases the mixed pore system signal by a displacement process. The true organic pores are not affected by the MnCl2 solution because an aqueous, water-based solution cannot displace dodecane by simple imbibition in an oil-wet pore. After 30 days of MnCl2 imbibition the signal remaining on the peak at 5 ms is due to true organic pores. Also, this organic pore system displayed a positive relationship with the TOC of each sample.

Upon placing samples in both a vacuum = 4x10-6 mTorr and 150°C for 2 weeks, the remaining NMR peak around 0.2 ms reached a threshold beyond which it could not be reduced. These NMR results mimicked the results achieved chemically by using a 65% MnCl2 aqueous solution for the same NMR peak. These two experimental results, in conjunction with an understanding that the NMR peak around 0.2 ms represents clay dominated pores, yield support to the notion that the remaining peak around 0.2 ms (after 1 month of MnCl2 aqueous solution imbibition) represents clay-bound water.

Ultimately, this study allows for the quantification of effective porosity, inorganic porosity, organic porosity, the porosity at the inorganic-organic interface and clay-bound water.
Haemoglobin polymorphism in selected farm animals: A review
Authors: Egena S.S.A. , Alao R.O.
Published: October 2014

Biochemical diversity or polymorphism is the occurrence of varieties
attributed to biochemical differences which are under genetic control. It has
created a leeway for the genetic improvement of farm animals. This is because
it can be used as a useful tool for the characterization of livestock breeds
and population. This way, the degree of similarity or differences within and
between breeds can be ascertained and this differences or similarity are
important raw materials for genetic improvement of animals. Data obtained on
gene frequencies and genotypes through polymorphism study makes it not only
possible to compare the gene stocks of animals, the possible effects of the
genes on reproductive and performance traits, but also study genetic
variability under different environmental conditions of selection. This study
was carried out to review haemoglobin (Hb) polymorphism in selected farm
animals with the view of finding out the type of polymorphism observed by
starch gel electrophoresis due to variation in the amino acid sequence in the
polypeptide chains of Hb. The review showed clearly that there is a
gene-controlled diversity in the different farm animals considered. This
could serve as a reference point for future studies earmarked for the
improvement of the animals possibly via marker-assisted selection.
Amounts of essential and non-essential amino acids and the ratio in Lithuania bred cattle meat
Authors: Jukna V. , Jukna C. , Meskinytė-Kausilienė E.
Published: October 2014

The aim of the research was to determine the amounts of essential and
non-essential amino acids and the ratio in various breed cattle meat. The
content of amino acids and the ratio at the longest dorsal muscle (musculus
longissimus dorsi) was determined analyzing Angus, Hereford, Charolais,
Limousine purebreds, Lithuanian Black and White x Charolais (LTBWxCHA)
crossbreed, Lithuanian Black and White x Limousine (LTBWxLI) crossbreed,
Lithuanian Black and White x Simmental (LTBWxSI) crossbreed and Lithuanian
Red x Limousine (LTRxLI) crossbreed. Analyzing the research results it was
noticed that Lithuanian Black and White cattle breed meat contained the
highest total amount of amino acids and Angus breed cattle meat contained the
smallest amounts. The difference amounted to 33.87 g/kg or 4.1 percent
(p<0.01). While comparing total amounts of amino acids at the purebred cattle
breeds and the crossbreeds, it was noticed that the meat of purebred cattle
contained higher amounts of amino acids, the difference ranging between 18.54
and 19.00 g/kg or 2.23-2.28 percent (p<0.01). Purebred cattle meat contains
higher amounts of essential amino acids compared to crossbreed cattle meat.
The meat of Aubrac and Angus breeds was determined to have the highest meat
protein sufficiency rate. The lowest biological values were determined at
Lithuanian Black and White x Charolais crossbreed meat. The highest amount of
the amino acid leucine was observed in Aubrac breed cattle meat (p<0.05). The
difference of the leucine amounts reached up to 0.45 g/kg (p<0.01) comparing
to various crossbreed cattle meat.
Eefects of different methods for myometrial contraction stimulation prior to AI on sows fertility
Authors: Stancic I. , Apic I. , Harvey R. , Anderson R. , Stevancevic O. , Stojanac N.
Published: October 2014

These study compares farrowing rate and litter size in AI sows, treated with
different methods for myometrial contraction stimulation, immediately around
AI. The total of 249 sows, inseminated within 7 days after weaning, were
divided into five groups. Group I: 10 IU oxytocine addition in semen dose
immediately before AI (n=50), Group II: i/m vulvar injection of 5 IU oxytocin
just prior to AI (n=50), Group III: cervix stimulation with AI catheter
(n=49), Group IV: fence-line boar contact immediately around AI (n=50) and
Group V: unstimulated AI (control) sows (n=50). Farrowing rate were
significant higher (P<0.05) in all stimulated sows groups (92%, 88%, 90% and
84%), compared with unstimulated sows (78%). Subsequent litter sizes were not
affected by treatment, ranged between 11.41 and 11.98 liveborn piglets. These
results indicate that performed treatment for myometrial contractions
stimulation can be useful method to improve sows fertility.
Permanence of sown sward situated along the slopes of the central Balkan Mountain
Authors: Mitev D. , Naydenova G.
Published: October 2014

The state of mixed swards of red fescue, Kentucky bluegrass and bird?s foot
trefoil was studied. The experiment was situated along the slopes of the
Central Balkan Mountain, during the period of the 1st to the 13th year of
their creation. At a high degree of soil gleying, the low part of the slope,
the dry matter yields were within the limits of 2.8 t/ha (1997, south-eastern
exposure) up to 10.66 t/ha (1999, north-eastern exposure). At a low degree of
soil gleying, high part of the slope, the dry matter yields were within the
limits of 2.34 t/ha (1994, western exposure) up to 14.34 t/ha (1995, east
exposure). The most prominent in productive terms for the period of the study
are the variants at the east and south-eastern exposure, slightly gleyed
soil. The participation of the sown species in the total forage yield is
variable quantity. They reach (at their most) up to 96% in 1998, north
exposure, slightly gleyed soils and up to 97% in 2000, north-east exposure,
highly gleyed soils. Their share was small in 2004 (44%) and in 2006 (42%) on
a western slope, highly eroded soils.
Anti-CD44 Antibody Treatment Lowers Hyperglycemia and Improves Insulin Resistance, Adipose Inflammation, and Hepatic Steatosis in Diet-Induced Obese Mice
Authors: Kodama Keiichi , Toda Kyoko , Morinaga Shojiroh , Yamada Satoru , Butte Atul J.
Published: October 2014

Type 2 diabetes (T2D) is a metabolic disease affecting >370 million people worldwide. It is characterized by obesity-induced insulin resistance, and growing evidence has indicated that this causative link between obesity and insulin resistance is associated with visceral adipose tissue inflammation. However, using anti-inflammatory drugs to treat insulin resistance and T2D is not a common practice. We recently applied a bioinformatics methodology to open public data and found that CD44 plays a critical role in the development of adipose tissue inflammation and insulin resistance. In this report, we examined the role of CD44 in T2D by administering daily injections of anti-CD44 monoclonal antibody (mAb) in a high-fat–diet mouse model. Four weeks of therapy with CD44 mAb suppressed visceral adipose tissue inflammation compared with controls and reduced fasting blood glucose levels, weight gain, liver steatosis, and insulin resistance to levels comparable to or better than therapy with the drugs metformin and pioglitazone. These findings suggest that CD44 mAb may be useful as a prototype drug for therapy of T2D by breaking the links between obesity and insulin resistance.
Performance and the Gendered Body in Jamaica Kincaid's “Girl” and Oonya Kempadoo's Buxton Spice
Authors: Bailey Carol
Published: October 2014

Jamaica Kincaid's compact and succinct story “Girl,” the lead story in the collection At the Bottom of the River (1983), has been lauded as one of the premier works in Kincaid's corpus, particularly her discourse on the making of “woman” in postcolonial Caribbean contexts. The text is essentially a set of instructions offered by an adult (assumed to be a mother), laying out the script for the performance of womanhood in the fictional society in which the female child is expected to live and perform her gender. “Girl”'s emphasis on performative acts reiterates the inextricable link between gender and performance. Undoubtedly, this landmark Kincaid story is in dialogue with Butler's theorization of the centrality of stylized acts in the creating and crafting of gendered selves. Less well known is Oonya Kempadoo's debut novel Buxton Spice (1999). Buxton Spice chronicles the experiences of four pubescent girls in 1970s Guyana as they learn about, participate in, and challenge some gender expectations of their immediate and wider communities. The story is told from the point of view of Lula, who keenly observes the ways in which gender roles are enacted and how these roles may be re-enacted. Her observations alert the reader to the novel's preoccupation with uncovering, or perhaps reconfiguring, how gender roles might be at once imagined and played out in contemporary Caribbean societies. Both texts illustrate how the tensions and contradictions surrounding the constructions of womanhood, and in Buxton Spice, manhood, are engaged through performative acts, some of which ostensibly conform to prescribed gender roles but that actually undermine them.
Excerpts from the Voices of Feminism Oral History Project
Authors: Saika Peggy , Ross Loretta
Published: October 2014

In this oral history, Saika underscores the lasting impact of the internment experience as a call to vigilance and action. She traces her political involvements from pan-Asian student activism in the late 1960s forward, marking her journey through various forms of organizing: direct service, civil rights, community organizing, and philanthropy. The interview offers a general outline of Saika's path as a postwar progressive who embraces her generation's challenge to build an ethnic movement that affirms Asian American identity and rights while it also advances a broad anti-racist, feminist, class-conscious social justice agenda.
Improving Learning in Primary Schools of Developing Countries
Authors: McEwan Patrick J.
Published: October 2014

I gathered 77 randomized experiments (with 111 treatment arms) that evaluated the effects of school-based interventions on learning in developing-country primary schools. On average, monetary grants and deworming treatments had mean effect sizes that were close to zero and not statistically significant. Nutritional treatments, treatments that disseminated information, and treatments that improved school management or supervision, had small mean effect sizes (0.04–0.06) that were not always robust to controls for study moderators. The largest mean effect sizes included treatments with computers or instructional technology (0.15); teacher training (0.12); smaller classes, smaller learning groups within classes, or ability grouping (0.12); contract or volunteer teachers (0.10); student and teacher performance incentives (0.09); and instructional materials (0.08). Metaregressions suggested that the effects of contract teachers and materials were partly accounted for by composite treatments that included training and/or class size reduction. There are insufficient data to judge the relative cost-effectiveness of categories of interventions.
Recurrent lacrimal abscess in infant
Authors: Mondal Monojit , Biswas Biswajit , Laha Sumanta , Roy Atanu , Barik Kanai Lal , Datta Asok Kumar , Bose Sayan , Biswas Tanmoy
Published: October 2014

Acute dacryocystitis at or shortly after birth is uncommon and its main complication, formation of lacrimal sac abscess, is rare. Uniform and standard treatment protocol for this condition has not been established till date. We report on a 2 month old infant with an abscess of the lacrimal sac. He was treated for similar condition on day 6 of his life by incision and drainage; unfortunately, the condition recurs. This time, he was managed with incision and drainage under systemic antibiotic cover; and an early probing of the nasolacrimal duct (NLD) was done on 7th post-operative day. The patient was followed up for a period of one year without any further recurrence and complication. Pathophysiology of the condition and possible treatment options in children have been discussed.DOI: http://dx.doi.org/10.3126/ajms.v6i2.10458Asian Journal of Medical Sciences Vol.6(2) 2015 121-123
Co-relating HbA1c and serum IgA in diabetic and non-diabetic patients with and without periodontitis
Authors: Deepti Chaurasia , Reena Kulshrestha , Pooja Sitholay , Gopinath V. , Rohit Agrawal , Vijayta Sharva
Published: October 2014

Objective: Diabetics are more susceptible to the infections than the non-diabetics (healthy) one, suggesting that the immunologic capability may be unbalanced in diabetics. Periodontitis is associated with alterations in immune responses in both diabetic and non-diabetic subjects. Till date various attempts has been taken to monitor host immunological response of diabetic individuals. Therefore the need to study the local immune response in inflamed gingival showing Periodontitis is apparent. Since till date there are no well documented and significant baseline studies are available on the functional capacities of the lymphoid cells present in gingiva of the periodontitis patients, a study to check the level of immunoglobulin was investigated.   Methodology: A study was carried out where HbA1c, Random Blood Sugar and Serum IgA level were assessed in 60 patients from the OPD of RCDSR. 15 patients each belonging to the four groups diabetic with periodontitis, diabetic without periodontitis, non-diabetic with periodontitis and non- diabetic without periodontitis (control) were analysed for the quantitative estimation of Serum Immunoglobulin A by Turbidometric Immunoassay and HbA1c was done by using Nyco card Reader.Result: The data thus obtained were compared with the level of immunoglobulin found in clinically healthy gingival of the control group. The levels of IgA were found to be high in group ‘A’ (Diabetic patients suffering from Periodontitis) group ‘B’ (Diabetic patients not suffering from Periodontitis) and group ‘C’ (Non-diabetic patients suffering from Periodontitis) but the values are not differing statistically from each other. But, the values of all these groups are statistically highly differed from the value obtained against the normal/healthy controlled group ‘D’.  Conclusion: In our study it can be concluded that there was positive co-relation between the two parameters: elevated HbA1c and Immunoglobulin level with periodontitis. This co-relates to the possibility of an underlying immuno-inflammatory abnormality to be the cause for the elevated level of immunoglobulin in our patients with elevated sugar level. DOI: http://dx.doi.org/10.3126/ajms.v6i2.11096Asian Journal of Medical Sciences Vol.6(2) 2015 72-77
Isolated Pulmonary Metastasis from Prostate Adenocarcinoma: Diagnosis by Fine Needle Aspiration Cytology
Authors: Khairwa Anju , Nalini Gupta , Manphool Singhal , Santosh Kumar , Arvind Rajwanshi
Published: October 2014

Prostate cancer usually metastasizes to regional lymph nodes and bone followed by distant organs. Here, we present a case of elderly man who had isolated respiratory symptoms and finally turned out to be metastasis from prostate cancer. Rarity of isolated pulmonary metastases of prostate cancer without bone and lymph node involment prompted us to report this case which was diagnosed by CT guided FNAC. DOI: http://dx.doi.org/10.3126/ajms.v6i2.11103Asian Journal of Medical Sciences Vol.6(2) 2015 111-114
Effect of Pre-Eclampsia on plasma and erythrocytic divalent cation concentrations and their Bioenergetics of Transport
Authors: Igwe C. U. , Okafor P. A. , Ibegbulem C. O. , Okwara J. E.
Published: October 2014

Background: Pre-eclampsia is a syndrome of pregnancy-induced hypertension with proteinuria, which has high prevalence rate among blacks.Aims and Objectives:To study the effect of pre-eclampsia on bioenergetics for the transport of erythrocytic cations to plasma, the plasma and erythrocytic levels of magnesium (Mg), calcium (Ca), copper (Cu), zinc (Zn), manganese (Mn) and selenium (Se) were measured by atomic absorption spectrophotometry in 100 pre-eclamptic women matched for gestation age with 100 normal pregnant subjects. These were also age-matched with 100 non-pregnant women.Results: The plasma and erythrocytic levels of the minerals were significantly (p < 0.05) lower in the pre-eclamptic patients than the healthy pregnant and the non-pregnant women. Although, levels of these minerals were also reduced in the healthy pregnant women relative to the non-pregnant subjects, only the plasma and erythrocytic levels of Ca, Cu, Mn and Se showed significant (p < 0.05) depreciations. Pre-eclampsia and pregnancy did not affect significantly (p > 0.05) the divalent-cation-based erythrocytic membrane free energy.Conclusion: Our results suggest that low levels of these minerals, especially Mg and Ca in pre-eclampsia, may have roles to play in the development of hypertension in these patients, and calls for intensified research into mineral supplementation as a key for possible prevention or management of pre-eclampsia.DOI: http://dx.doi.org/10.3126/ajms.v6i2.11109Asian Journal of Medical Sciences Vol.6(2) 2015 19-24
Free PSA: A better molecular marker than total PSA for breast cancer
Authors: Nanda Rachita
Published: October 2014

Serum total PSA (prostate specific antigen) has been considered since some time for diagnosis or prognosis of breast cancer. PSA is present both as free and complexed form. Many researchers have shown total PSA increases in all forms of breast disease, whether cancerous or benign lesions. Few scientists  have demonstrated that the free form of PSA is the predominant form in breast cancer.1,2  Also the observation that there is a marginal reduction in total PSA after surgery in comparison to a remarkable decrease in free PSA is a strong indicator that a large portion of total PSA is produced by normal tissue and that free PSA is produced by breast tumors.3,4,5 Moreover  free PSA as the predominant form was found to be highly specific for breast cancer when compared to benign and normal tissues.3 In India, Dash et al.,(2011) in their study in Indian population observed similar results using total and free PSA in patients of breast tumors 5 augmenting  its role as a prognostic marker. With a heterogeneous  study population in India where breast cancer is commonly encountered, population based studies  are essential to study the molecular forms of PSA  with respect to  the disease process  like relapse or metastasis and therefore with future treatment. DOI: http://dx.doi.org/10.3126/ajms.v6i2.11110Asian Journal of Medical Sciences Vol.6(2) 2015 129
Active lakes of Recovery Ice Stream, East Antarctica: a bedrock-controlled subglacial hydrological system
Authors: Fricker Helen Amanda , Carter Sasha P. , Bell Robin E. , Scambos Ted
Published: October 2014

A connected system of active subglacial lakes was revealed beneath Recovery Ice Stream, East Antarctica, by ICESat laser altimetry. Here we combine repeat-track analysis of ICESat (2003–09), Operation IceBridge laser altimetry and radio-echo sounding (2011 and 2012), and MODIS image differencing (2009–2011) to learn more about the lake activity history, the surface and bedrock topographic setting of the lakes and the constraints on water flow through the system. We extend the lake activity time series to 2012 for the three lower lakes and capture two major lake drainages. One lake underwent a large deflation between 2009 and 2011 while another lake, which had been continuously filling between 2003 and 2010, started to drain after 2011. Most of the active lakes are located in a ~ 1000 km long bedrock trough under the main trunk of Recovery Ice Stream, whose base is ~ 1500– 2000 m below present-day sea level. The hydrologic system beneath Recovery Ice Stream is controlled by this unusually pronounced bedrock topography, in contrast to most Antarctic systems studied to date, which are controlled by the ice surface topography. Hydrologic connections among the lakes appear to be direct and responsive, and we reproduce the lake activity using a simple subglacial water model. We discuss potential causes of non-steady hydrologic behavior in major Antarctic catchments.
Evaluating the Quality and Accuracy of TanDEM-X Digital Elevation Models at Archaeological Sites in the Cilician Plain, Turkey
Authors: Erasmi Stefan , Rosenbauer Ralph , Buchbach Ralf , Busche Thomas , Rutishauser Susanne
Published: October 2014

Satellite remote sensing provides a powerful instrument for mapping and monitoring traces of historical settlements and infrastructure, not only in distant areas and crisis regions. It helps archaeologists to embed their findings from field surveys into the broader context of the landscape. With the start of the TanDEM-X mission, spatially explicit 3D-information is available to researchers at an unprecedented resolution worldwide. We examined different experimental TanDEM-X digital elevation models (DEM) that were processed from two different imaging modes (Stripmap/High Resolution Spotlight) using the operational alternating bistatic acquisition mode. The quality and accuracy of the experimental DEM products was compared to other available DEM products and a high precision archaeological field survey. The results indicate the potential of TanDEM-X Stripmap (SM) data for mapping surface elements at regional scale. For the alluvial plain of Cilicia, a suspected palaeochannel could be reconstructed. At the local scale, DEM products from TanDEM-X High Resolution Spotlight (HS) mode were processed at 2 m spatial resolution using a merge of two monostatic/bistatic interferograms. The absolute and relative vertical accuracy of the outcome meet the specification of high resolution elevation data (HRE) standards from the National System for Geospatial Intelligence (NSG) at the HRE20 level.
Correlation of X-Ray Computed Tomography with Quantitative Nuclear Magnetic Resonance Methods for Pre-Clinical Measurement of Adipose and Lean Tissues in Living Mice
Authors: Metzinger Matthew , Miramontes Bernadette , Zhou Peng , Liu Yueying , Chapman Sarah , Sun Lucy , Sasser Todd , Duffield Giles , Stack M. , Leevy W.
Published: October 2014

Numerous obesity studies have coupled murine models with non-invasive methods to quantify body composition in longitudinal experiments, including X-ray computed tomography (CT) or quantitative nuclear magnetic resonance (QMR). Both microCT and QMR have been separately validated with invasive techniques of adipose tissue quantification, like post-mortem fat extraction and measurement. Here we report a head-to-head study of both protocols using oil phantoms and mouse populations to determine the parameters that best align CT data with that from QMR. First, an in vitro analysis of oil/water mixtures was used to calibrate and assess the overall accuracy of microCT vs. QMR data. Next, experiments were conducted with two cohorts of living mice (either homogenous or heterogeneous by sex, age and genetic backgrounds) to assess the microCT imaging technique for adipose tissue segmentation and quantification relative to QMR. Adipose mass values were obtained from microCT data with three different resolutions, after which the data were analyzed with different filter and segmentation settings. Strong linearity was noted between the adipose mass values obtained with microCT and QMR, with optimal parameters and scan conditions reported herein. Lean tissue (muscle, internal organs) was also segmented and quantified using the microCT method relative to the analogous QMR values. Overall, the rigorous calibration and validation of the microCT method for murine body composition, relative to QMR, ensures its validity for segmentation, quantification and visualization of both adipose and lean tissues.