bluuebunny/crossref_metadata_2025_split huggingface dataset:
Neural-net Modeling of Shale-swelling Behavior in Aqueous Drilling Fluids
Authors: Maghrabi Shadaab , Kulkarni Dhanashree , Teke Kushabhau , Kulkarni Sandeep D. , Jamison Dale 
Published: October 2013

Abstract
Managing shale swelling is critical when drilling with water-based muds (WBMs). Excessive swelling can lead to shale sloughing, borehole collapse, stuck pipe, and shale disintegration. The fine solids content can increase and cause difficulties controlling rheological properties. Linear swell meter (LSM) testing is a well-known laboratory procedure used to characterize shale swelling in a WBMs.
A mathematical modeling tool known as the artificial neural network (ANN) was used to model shale swelling in a WBM. The ANN model establishes complex relationships between a set of inputs and an output based on computational modeling. For ANN modeling of the shale-swelling, the shale mineralogy and fluid composition constituted input parameters, while the output was represented by an experimental characteristic swelling parameter derived from the "% swelling vs. time" data from the LSM test for the respective shale-fluid combinations.
Experimental data for building the ANN model was obtained by performing about 250 standard LSM tests on different shales with varying mineralogy and WBMs with varying salt concentrations. This shale swelling ANN model provided excellent correlation with R2 &gt; 0.9. The ANN model was then successfully validated for an independent set of shale-fluid conditions.
Using the shale swelling ANN model, shale-swelling in WBM was predicted for a given shale mineralogy and fluid composition. This reduced the number of trials necessary to determine an optimized WBM formulation. Mud engineers can use this model in real-time as the shale chemistry varies with the depth of the formation drilled. The model provides a helpful measure of fluid performance to determine the optimization necessary to obtain the desired shale behavior. Using this method can help minimize drilling risks and costs associated with unpredictable shales.
Well Integrity: Application of Ultrasonic Logging, Production Logging and Corrosion Logs for Leak Detection in Wells - A Case Study
Authors: Jalan Shiv N. , Al-Humoud Jamal , Al-Sabea Salem , Gazi Naz , Al-Azmi Khalid , Al-Haddad Saud , Abdulrazzaq E.. , Al-Baghli Fatma , Khalil Mamdouh , Zaki Hasan , Fahrizal A.. 
Published: October 2013

Abstract
Well integrity is one of the critical concern during the life cycle of wells and impose an enormous challenge to the oil & gas industry. External and/or Internal corrosion of tubing & casing is one of the main reasons of leaks in the wells causing fluid movement from one annulus to other annulus. Complete understanding of the source of pressure communication between different annuli is of prime importance for designing an effective remedial action. Most leaks can worsen with time and therefore, locating and repairing a leak in its early stages is essential otherwise it may sometimes lead to abandonment of the well. Knowing the precise location of a leak prior to executing repair jobs will lead to better planning thus reducing downtime and repair costs. The problem becomes more complicated when the leak diagnosis has to be done using conventional logging techniques without pulling out the tubing string.
Presence of competent barriers is a fundamental imperative of well integrity. Imperfect barriers introduce risks that need assessment and management. Few wells go through their operating life cycle without undergoing material degradation and component failures resulting in imperfect barriers. Therefore, use of contingent barriers is necessary to minimize the likelihood of such failures and the resultant impact.
This paper describes different types of through tubing logging techniques used by Kuwait Oil Company for identifying tubing-casing leak in an oil well and discusses the interpretation of the results. The paper also discusses the probable reasons for occurrence of the leak, remedial actions taken to arrest the leak and future completion philosophy to avoid such failures in the new wells.
Impact of Rock Mechanics and Formation Softening Analysis in Shale Fracturing Fluid Design
Authors: Das Prasanta , Achalpurkar Manojkumar 
Published: October 2013

Abstract
For low-permeability formations, such as oil- and gas-bearing shales, hydraulic fracturing stimulation is a requisite to obtain commercial production. One of the key parameters for ensuring successful stimulation and prolonged production is the proper selection of stimulation fluid. The selection and optimization of the fracturing fluid is greatly dependent on the reservoir rock properties as well as the formation softening resulting from fluid-formation interaction.
In the past, slickwater treatment fluids often were adopted in tight shale plays for creating a complex fracture network for maximum production yield. Most often, the slickwater recipe is driven by formation fluid sensitivity analysis (e.g., effect of fresh water, salt, or acids on the formation). While this might work for a few formations, the rock mechanical properties, such as Young's modulus and Poisson's ratio, will determine the fracability and whether it is advantageous to use slickwater, linear gel, or crosslinked gel. Similarly, formation softening analysis using a Brinell hardness test and proppant embedment test will ensure that the formation does not close upon fluid treatment and will have conductive flow channels. This paper discusses the impact of different types of fracturing fluids on different shale formations. The paper also discusses processes involving fluid sensitivity tests, formation softening, and rock mechanical tests and shows their influence on the choice of the proper fluid formulation for hydraulic fracturing through data from a few test samples.
The formation rock, proppant, and fracturing fluid interaction can also cause diagenetic growth on proppant and formation faces, resulting in formation softening and a large decrease in fracture conductivity. This paper focusses on careful selection of the stimulation fluid based on rock parameters to ensure prolonged production in tight oil and gas shale plays.
Development of Strategic Facilities Plan for Wafra Joint Operations
Authors: Castro E. A. , Al-Hasawi G.. , Zaheer A.. 
Published: October 2013

AbstractAt the beginning of each field development there are Field Development Plans (FDPs) made with great detail on how facilities will be built to support that development. After several years of development the initial assumptions and originally documented field development plan change because of new reservoir information, market changes, etc. FDPs are then changed to Field Depletion Plans or Asset developments Plans. However, the level of detail of the corresponding facility plans to support the updated plans are usually not comprehensive enough to support the planned field depletion plans or asset development plans.In Wafra Joint Operations, the lack of facility plans led to an inflated budget request log in excess of $800 MM. In short, the budget request log lacked comprehensiveness, did not show interlinks between budget request line items, did not tie in facility upgrades with asset development plans, and lacked prioritization. These issues in turn reduced capital efficiency, lead to excessive lost production events, constrained supply chain with low valued added facility upgrades, and in the misappropriation of the available engineering resources.There are many papers and case studies1, 2, 3 that show how to comprehensively develop Field Development Plans. However, there has been little work on how to update or revise those facility plans after the field development plans are changed to asset development or depletion plans. In latter, different focus areas are required. The sections below will show how the facility plans for Wafra Joint Operations were developed into the Strategic Facilities Plan.
Laboratory Performance Evaluation of WAG Process for Carbonate Reservoir at Reservoir Condition
Authors: Zhou Xianmin , Al-Otaibi Fawaz , Kokal Sunil 
Published: October 2013

AbstractRemaining oil production after water flooding, water cut, flow characteristics and injectivity of supercritical CO2 and water play an important role in the modeling and reservoir performance prediction for a CO2 miscible WAG injection process. Six cyclic WAG displacements of supercritical CO2/live crude oil in watered-out carbonate composite cores were performed to study the performance of supercritical CO2 WAG process at reservoir conditions in great detail. The water cut during supercritical CO2 WAG process, endpoint relative permeability to oil in the miscible zone, Krom, oil bank, Kro, and to water, Krw for the water injection cycle, and injectivity for all supercritical CO2 WAG injection cycles are presented in this paper. The viscosity of supercritical CO2/live crude oil, µom in miscible zone is predicted using a Genetic Algorithm-based model and parameters of a live crude oil to calculate the endpoint relative permeability to oil, Krom, in miscible zone.Based on supercritical CO2 core flooding data and performance of the water cut, injectivity and endpoint relative permeability for supercritical CO2 WAG process, the results indicate: 1) the oil bank and miscible zone were built up when supercritical CO2 was injected in the 1st and 2nd cycle and oil mobility was improved significantly. The remaining oil after initial water flooding was recovered mostly after the 2nd-water injection cycle and water cut dropped quickly in the 1st-water and 2nd supercritical CO2 injection cycles; 2) endpoint relative permeability, Krom in the miscible zone was higher than that of oil-endpoint relative permeability, Kro in the oil bank, and maximum value was observed at critical cycle (2nd cycle). There was a significant difference in water-endpoint relative permeability, Krw between supercritical CO2 and water injection. Krw- endpoint relative permeabilities of water injection were greater than the values of the supercritical CO2 injection. Krom and Kro endpoint relative permeability decreases quickly after the 2nd cycle of supercritical CO2 and water injection; 3) water injectivity was higher than values for supercritical CO2 injection, but the differential between water and supercritical CO2 injection was a little; 4) The viscosity of supercritical CO2/live crude oil in the miscible zone can be predicted using a Genetic Algorithm-based model, which was approximately half of the live oil viscosity in the oil bank for this study.
MTHFR C677T and A1298C Genotypes and Haplotypes in Slovenian Couples with Unexplained Infertility Problems and in Embryonic Tissues from Spontaneous Abortions
Authors: Stangler Herodež Š , Zagradišnik B , Erjavec Škerget A , Zagorac A , Takač I , Vlaisavljević V , Lokar L , Kokalj Vokač N 
Published: October 2013

Abstract
The objective of this study was to analyze the methylenetetrahydrofolate reductases (MTHFRs) C677T and A1298C genotype distributions in couples with unexplained fertility problems (UFP) and healthy controls, and to analyze the genotype and haplotype distribution in spontaneously aborted embryonic tissues (SAET) using allele specific polymerase chain reaction (PCR) in 200 probands with UFP, 353 samples of SAET and 222 healthy controls. The analysis revealed a significant overall representation of the 677T allele in male probands from couples with UFP (p = 0.036). The combined genotype distribution for both MTHFR polymorphisms was also significantly altered (χ2 21.73, p <0.001) although female probands made no contribution (c2 1.33, p = 0.72). The overall representation of the 677T allele was more pronounced in SAET (0.5 vs. 0.351 in controls, p <0.001) regardless of the karyotype status (aneuploidy vs. normal karyotype). In addition, the frequencies of the CA and CC haplotypes were significantly lower than in the control group (p = 0.021 and p = 0.001, respectively), whereas the frequency of the TC haplotype was significantly higher than in controls (p <0.0001). The presented findings indicate that only male probands contribute to the association of MTHFR mutations with fertility problems in grown adults and demonstrate a high prevalence of mutated MTHFR genotypes in SAET.
A Rare Association of Monosomy 18P Syndrome and Polyglandular Autoimmune Syndrome Type IIIA
Authors: Dolek-Cetinkaya D , Demirpence M.M. , Gorgel A , Salgur F , Bahceci M 
Published: October 2013

Abstract We report a monosomy 18p syndrome in a male patient with polyglandular autoimmune syndrome (PAS) type IIIA. A 34-year-old mentally retarded diabetic male patient with short stature, wide earlaps, old-looking face, straight nasal bone, atrophic mouth, drooping cheeks, full teeth loss, and soft, weak and sparse white hair was admitted to the outpatient endocrinology clinic. Chromosome analysis of the patient revealed 46,XY,del(18)(p11.2). He was also diagnosed with autoimmune thyroiditis, primary hypothyroidism and diabetes mellitus type 1. We concluded that monosomy 18p syndrome may be associated with autoimmune diseases and if this is suspected, patients should be examined for an endocrine deficiency.
Emergence of the pandemic H1N1 2009 influenza A virus in swine herds in Poland
Authors: Markowska-Daniel Iwona , Urbaniak Kinga , Porowski Marian , Karbowiak Paweł , Kowalczyk Andrzej , Kozak Edyta , Pejsak Zygmunt 
Published: October 2013

Abstract
The outbreaks of pandemic H1N1 influenza A virus (pdm-like H1N1 2009), detected for the first time in farrow-to-finish farms in Poland, were described. The nasal swabs and lung tissue collected from diseased/dead animals were tested using molecular techniques (RRT-PCR, MRT-PCR, RT-PCR, SSG-PCR, sequencing) and virus isolation. The amplification of the genetic material extracted from the tested samples confirmed the presence of the M1 gene sequence of type A influenza virus. Using MRT-PCRs no products characteristic for HA and NA of any swine influenza virus subtypes were obtained. Using SSGPCR, products specific for pandemic HA and NA gene fragments were detected. Six new pdm-like H1N1 2009 strains were isolated and characterised. Phylogenetic analysis of the HA and NA genes revealed that they belong to one lineage with the pandemic strain A/California/04/2009 and other human strains, including human strains isolated in Poland in 2011.
Evaluation of diagnostic methods to distinguish between calves persistently and transiently infected with bovine viral diarrhoea virus in respect to the presence of maternal antibodies
Authors: Larska Magdalena , Kuta Aleksandra , Polak Mirosław P. 
Published: October 2013

Abstract
Two issues concerning virus detection and identification of persistently infected (PI) cattle were analysed in the study: 1) interference by maternal antibodies and 2) discrimination between PI and transiently infected (TI) animals. Antigen ELISA and RT-PCR based methods were compared using serum samples from natural and experimental PI and TI calves. RT-PCR and realtime RT-PCR using primers within 5’UTR region were more sensitive in detecting PI animals than Erns and NS3 antigen capture ELISAs, and they were not influenced by the presence of colostral antibodies in serum or by bovine viral diarrhoea virus genotype. The serum samples with Ct values ≤ 29.10 (corresponding to 104.87 viral RNA copies/μL) identified PI animals with 100% probability, while all samples with Ct values > 32.06 (corresponding to viral RNA load below 104 copies/μL) indicated TI status. The samples with Ct values between 29.10 and 32.06 (17.2% of PI and 11.5% of TI) should be considered as PI suspect and retested.
Wild boar meat sensory attributes contributing general meat quality
Authors: Guzek Dominika , Głąbska Dominika , Plewa Paweł , Kozań Karolina , Pietras Jacek , Plewa Rafał , Pogorzelska Ewelina , Pogorzelski Grzegorz , Trajer Jędrzej , Wierzbicka Agnieszka 
Published: October 2013

Abstract
The purpose of the study was to establish relationship between different sensory attributes of wild boar meat, as well as to develop a prediction model of sensory attributes demanded. The sensory analysis of 40 samples of wild boar meat (the loin) was performed. For wild boar meat, tenderness, juiciness, colour, taste, aroma, and off-flavours are significantly correlated with general quality of meat, assessed by the sensory panel. The results from the study indicate that wild boar meat reveals characteristic sensory traits; however, texture as well as off-flavours do not play an important role in creating general quality, but the most important factors influencing the general quality of wild boar meat included juiciness, colour, taste, and aroma.
Assessment of semen quality in infertile dogs using computer-assisted sperm analysis by the Hamilton-Thorne Semen Analyser
Authors: Domosławska Anna , Zduńczyk Sławomir , Niżański Wojciech , Janowski Tomasz 
Published: October 2013

Abstract
Semen quality parameters of infertile and fertile dogs were compared. Sperm concentration and semen motility parameters were measured by the Hamilton-Thorne Semen Analyser IVOS 12.3. The spermatozoal morphology and the percentage of live spermatozoa were examined microscopically. Forty-six dogs of various breeds were examined. Twenty dogs had a conception failure within last year. These dogs had a history of prior normal fertility. Twenty six fertile dogs served as control. All animals underwent a clinical examination as well as ultrasonography. Sperm concentration was significantly lower in infertile dogs than in fertile dogs. For most determined motility parameters (MOT, PMOT, VAP, VSL, VCL, BCF, RAPID, STATIC) significant differences between infertile and fertile dogs were found. The percentage of spermatozoa with normal morphology also significantly differed between both groups. Ultrasonography of the prostate gland and testes revealed no pathological conditions. The testicular degeneration was assumed to be a possible cause of infertility in these dogs. The present study showed that the most sperm CASA motility parameters were significantly lower in infertile dogs in comparison to the fertile ones, and confirmed the usefulness of the Hamilton-Thorne Semen Analyser for a quick and objective analysis of sperm concentration and motility in dogs.
P-R interval in porcine model of chronic tachycardia-induced cardiomyopathy
Authors: Skrzypczak Piotr , Zyśko Dorota , Pasławska Urszula , Noszczyk-Nowak Agnieszka , Janiszewski Adrian , Kiczak Liliana , Bania Jacek , Zacharski Maciej , Tomaszek Alicja , Rybińska Ilona , Nicpoń Józef , Pasławski Robert , Gajek Jacek , Jankowska Ewa A. , Ponikowski Piotr 
Published: October 2013

Abstract
The aim of the study was to assess the atrioventricular conduction in the model of porcine pacing induced tachycardiomyopathy. Fifty-one swine were examined: 27 were paced and 24 served as a control group. Every 4 weeks, the animals were anaesthetised for 1 h and an ECG Holter was performed. Thirty minutes after the onset of anaesthesia, P-R and R-R intervals were measured. Each result was assigned to the subgroup according to the animal’s weight and the presence or absence of previous pacing. P-R interval was longer in animals after at least 4 weeks of rapid ventricular stimulation than in adjusted group of the animals according to the body mass. Multivariate analysis has showed that longer P-R interval was related to male gender, higher body mass, slower heart rate, and history of previous pacing. Chronic ventricular pacing led to the slowing of atrioventricular conduction. The presence of differences in the duration of R-R intervals between groups was only found in swine weighing 120-139 kg. The R-R interval was shorter in paced animals, whereas PR interval was longer in that group, indicating that PR prolongation is related to electrical or structural remodelling of the cardiac conductive tissue but not increased sympathetic nervous system activity, which is expected to produce corresponding changes in PR and R-R intervals.
Ghrelin concentration in half-blood jumping horses during moderate and intense training exercise
Authors: Bis-Wencel Hanna , Lutnicki Krzysztof , Rowicka Agnieszka Zofia , Bryl Monika , Nowakowicz-Dębek Bożena 
Published: October 2013

Abstract
The aim of the study was to assess the impact of varying intensity of exercise on ghrelin levels in half-blood jumping horses during training season. Blood samples were collected in the period of intense and moderate exercise. Serum concentrations of active and total ghrelin were measured using commercial RIA kits. Exercise did not cause the disruption in energy homeostasis, which was confirmed by the conducted tests. Total concentration of ghrelin measured during the increased effort intensity elevated in stallions (from 1031.45 to 1732.19 pg/mL at P ≤ 0.05). The opposite situation occurred in the case of active ghrelin, which concentration did not increase significantly in mares (from 26.21 to 28.46 pg/mL), whereas an insignificant decrease was noted in stallions (from 24.19 to 22.54 pg/mL). The only significant difference between stallions and mares was noted in the 2nd sampling (P = 0.015). The research proved that the fluctuations of both studied parameters did not reflect a negative impact of the increased effort.
Comparison of the influence of selenium supplementation in organic and inorganic forms on oxidant/antioxidant balance in rat lungs
Authors: Musik Irena , Kiełczykowska Małgorzata , Kocot Joanna 
Published: October 2013

Abstract
The aim of the experiment was to compare the effect of two newly synthesised organic selenocompounds with that exerted by sodium selenite on oxidant processes in rat lungs. Total antioxidant status (TAS), activity of antioxidant enzymes - superoxide dismutase (SOD) and glutathione peroxidase (GPx), concentrations of non-enzymatic antioxidants - ascorbic acid (AA) and reduced glutathione (GSH), concentration of lipid peroxidation marker - malonyldialdehyde (MDA), as well as tissue concentrations of silicon and magnesium were determined in rats receiving different selenocompounds (inorganic selenite and organic selenosemicarbazide in a chain form - compound A and selenazoline in a ring form - compound B). TAS values were elevated in comparison with control without Se-supplementation. GPx was insignificantly increased when compared to control, mainly in the group receiving compound B. Inorganic selenite significantly increased SOD and decreased levels of AA. MDA was slightly altered in Se-supplemented animals. Silicon levels were not affected, whereas magnesium concentrations were considerably reduced in all groups receiving selenium. Compound B increased TAS to the highest degree. It did not have any impact on components of the antioxidant barrier and slightly decreased MDA. Therefore, it could be suggested that further research, including in vitro studies on cancer cell lines, may reveal new possibilities of medical applications of selenocompounds