bluuebunny/crossref_metadata_2025_split huggingface dataset:
Buckling of Tubing Inside Casing
Authors: Mitchell Robert F. 
Published: November 2012

Summary
Oil wells typically have multiple concentric casing strings. For a set of two concentric strings, if the inner pipe has a compressive axial force, it will typically buckle within the outer string. The buckling of pipe can be important in the analysis of a well-completion design because the buckled pipe can develop bending stresses that may be significant. Most analyses of this problem assume that the outer casing is rigid. In reality, this external casing is also elastic and would displace owing to the loads generated by contact with the inner pipe. Further, if both strings have compressive axial forces, both strings will buckle, and the resulting buckled configuration must fit together so that contact forces between the two strings are positive and the pipes do not each occupy the same space. If the two strings have an external, cylindrical rigid wellbore, then any contact forces with this wellbore must also be positive, and the buckled pipe system must lie within this wellbore.
The only known solution to the multiple concentric pipe-buckling problem is that of Christman (1976), who proposed a composite pipe based on the summed properties of the individual pipes. This analysis does not conform to the requirements posed in the preceding paragraph.
This paper presents the various ways that two concentric pipes can interact when one or both pipes are in compression and would then have a tendency to buckle. The contact forces between the pipes and with the external wellbore are explicitly calculated, and contact or noncontact conditions are determined. All results are analytical so that they can easily be used in spreadsheets or hand calculations. Several examples of calculations are presented to illustrate how these results might be used.
Measurements of Hydraulic-Fracture-Induced Seismicity in Gas Shales
Authors: Warpinski N.R.. R. , Du J.. , Zimmer U.. 
Published: November 2012

SummaryHydraulic fracturing is an essential technology for hydrocarbon extraction from both conventional and unconventional reservoirs. Recently, concern has developed regarding induced seismicity generated in association with multistage fracturing of horizontal wells in shale reservoirs. Microseismic monitoring of hydraulic fractures, which has been a routine service for over a decade, can provide information about the levels of seismic activity commonly found during fracturing. A review of thousands of fracture treatments that have been microseismically monitored shows that the induced seismicity associated with hydraulic fracturing is very small and not a problem under any normal circumstances. Results are presented for six major shale basins in North America in which hundreds to thousands of fracture treatments have been conducted in predominatly gas reservoirs. This paper reviews the methodology, the data, and the interpretation of the microseismicity.
Surface and Subsurface Requirements for Successful Implementation of Offshore Chemical Enhanced Oil Recovery
Authors: Raney Kirk , Ayirala Subhash , Chin Robert , Verbeek Paul 
Published: November 2012

Summary
Chemical enhanced oil recovery (EOR), including polymer and surfactant-based processes, is a method that operators consider to maximize oil recovery from onshore and offshore reservoirs. Because of the logistical, operational, and environmental differences and the footprint and required weight needed for additional injection and production equipment, offshore chemical EOR processes are challenged by greater complexity and costs as compared with onshore applications of the same technologies.
Chemical EOR commonly requires large volumes of injection chemicals, as well as demulsifiers to break produced-water/oil emulsions and inhibitors to control scale, resulting in high shipment and storage costs. The use of seawater and/or produced water for injection of the chemicals into offshore fields mandates stringent processing of both streams to allow optimal injectivity, sweep efficiency, and chemical effectiveness in the reservoir. Offshore production of saleable oil and clean water requires space- and weight-efficient oil/water-separation equipment. Currently, conventional methods for processing produced fluids fall short in both efficiency and compactness. High offshore drilling costs lead to relatively large well spacing and more difficulty in monitoring the EOR subsurface process, and lead to restrictions on the number of disposal wells. Finally, environmental restrictions limit the overboarding of toxic or poorly biodegradable EOR chemicals.
The industry is currently investigating the limiting factors pertinent to offshore chemical EOR. As a result of these efforts, new enabling chemistries and technologies are being examined for improving surface operations to allow cost-effective offshore chemical EOR to be performed in an environmentally sound and safe manner. Some of these recent chemical- and fluids-processing developments are described in this paper. Subsurface challenges to implementing offshore chemical EOR are also highlighted, along with potential solutions.
Introducing a New Correlation for Multiphase Flow Through Surface Chokes With Newly Incorporated Parameters
Authors: Safar Beiranvand Mahmoud , Babaei Khorzoughi Mohammad 
Published: November 2012

Summary
Flow-rate prediction of oil production wells is of prime importance to effectively confront high-water-cut and separator problems. (Semi-) empirical multiphase-flow correlations are proved quite useful for this purpose. This work presents new generalized multiphase flow choke correlation, derived on the basis of actual production data from horizontal and vertical wells from an oil field in Iran. The newly established correlation predicts liquid flow rates as a function of flowing wellhead pressure, gas/liquid ratio, surface wellhead choke size, and the newly incorporated parameters: basic sediment and water (BS&W) and temperature. To evaluate the influence of these two new parameters, a parameter-sensitivity analysis was performed and the results are shown. This proposed correlation exhibited an average error of roughly 2.89%, which is superior to those previous correlations in the literature that did not use these two newly incorporated parameters (BS&W and temperature). These new parameters can be added to the previous correlations when the water cut and temperature become important in the production history of the wells.
Study on the FOG-Based Well-Trajectory-Logging Tool
Authors: Ren C.. , Li M.. , Li L.. , Duan Y.. , Weng H.. 
Published: November 2012

Summary
The commonly used technology in well-trajectory logging, for both the oil and the gas well, is the magnetometer. However, it cannot work well in the magnetic-interfered or nonmagnetic environment, such as in a cased well or an iron mine. This paper presents a new trajectory-logging tool with a small diameter. Configured by a three-axis FOG unit and three quartz accelerometers, the logging tool allows for continuous attitude and trajectory measurement. High-temperature-caused accuracy degradation is the major error source for the underground environment. To diminish the thermal-related error, a flask stuffed with thermal-insulation material was embedded in the tool body; meanwhile, a wavelet neural network was used for identification of and compensation for the temperature drift. The system configuration, trajectory-resolution algorithm, and temperature-compensation algorithm are presented in this paper. Testing results show that the inclination accuracy is better than ±0.1°, with a range of 0 to 180°, and the azimuth accuracy is better than ±2°, with a range of 0 to 360°. The new logging tool resolves continuous trajectory-measurement problems in a magnetic-interfered or a nonmagnetic environment. Moreover, the capability of all-attitude measuring facilitates horizontal-well logging. Therefore, broad applications and good marketing could be anticipated for this new logging tool.
Experimental Study of Two-Phase Performance of an Electric-Submersible-Pump Stage
Authors: Gamboa Jose , Prado Mauricio 
Published: November 2012

Summary
This paper presents electric-submersible-pump (ESP) -stage performance handling air and water in a laboratory setup. Experimental data gathered shows the effect of volumetric gas flow rate and intake-stage pressure for different rotational speeds. The presence of gas mildly deteriorates the stage performance at low volumetric gas flow rates. A sudden reduction in the stage-pressure increment is observed at this operation condition for a certain critical liquid flow rate, which marks the initiation of surging on the stage performance as mentioned by Lea and Bearden (1982). The surging initiates at lower liquid flow rates as the volumetric gas flow rate increases, which demonstrates the relationship between the surging initiation and liquid flow rate. It is also observed that the initiation of the surging moves toward lower liquid flow rates by increasing the rotational speed or the stage intake pressure.
A two-phase stage-performance map was recently introduced, defining boundaries for five pump-performance regimes: homogenous, mild-performance deterioration, performance reverse slop, server performance deterioration, and nil performance (Gamboa and Prado 2011b). The current work shows that these performance regime boundaries are affected by rotational speed and intake-stage pressure.
Annexin V antibodies in multiple sclerosis and SLE/APS
Authors: Baleva Marta , Stoilova Detelina , Shotekov Petko , Nikolov Krasimir 
Published: November 2012

Abstract
Multiple sclerosis (MS) is an autoimmune disease with unclear etiopathogenesis. Some MS patients have anticardiolipin (ACL), anti-beta-2-glycoprotein-I (B2GPI) and anti-annexin V (AnV) antibodies. These antibodies can also be found in systemic lupus erythematosus with antiphospholipid syndrome (SLE/APS). The aim of our study was to compare the levels of ACL, B2GPI and AnV antibodies in MS and SLE/APS. Materials and methods: We investigated serum levels of IgG and IgM ACL, B2GPI and AnV in 21 MS patients, 30 SLE/APS patients and 30 controls using ELISA. Results: Mean levels of IgM and IgG ACL and B2GPI in MS were comparable with controls and lower than SLE/APS (p<0.05). Mean levels of IgM AnV in MS were higher compared to SLE/APS and controls (p<0.05); mean levels of IgG AnV in MS were higher than normal but similar to SLE/APS (p>0.05). Discussion: The results show that MS with negative “classic” autoantibodies (ACL and B2GPI) and without clinical data for antiphospholipid syndrome may have other positive antiphospholipid antibodies, such as AnV. Larger studies are needed to clarify whether AnV are epiphenomenon of the vascular and organ damage or they play a pathogenic role in the development of MS.
Epiretinal membrane and cataract in a 5-year-old boy with the suspicion of neurofibromatosis type 2
Authors: Siwiec-Proscinska Joanna , Gotz-Wieckowska Anna , Pawlak Marta , Kociecki Jaroslaw 
Published: November 2012

Abstract
Different ocular findings have been described in association with neurofibromatosis 2 (NF2). Detailed ophthalmological examination of asymptomatic subjects with a family history of NF2 could help confirm the diagnosis in young patients. We present a case of unilateral cataract and bilateral epiretinal membranes in a 5-year-old boy with a family history of neurofibromatosis 2. The patient was referred to our department with diminished visual acuity bilaterally and an initial diagnosis of cataract in the right eye. Bestcorrected visual acuity was 3/19 in the right eye and 3/24 in the left eye (LH charts). On fundus examination, bilateral macular epiretinal membranes were found and confirmed by optical coherent tomography. In view of the ophthalmic signs mentioned above and the history of the patient’s father, who suffered from NF2 and died from meningioma and ependymoma, the patient was referred for genetic examination. Seventeen exons of the NF2 gene were tested with negative results. No pathology was found on clinical neurologic examination and magnetic resonance imaging of the brain. Although the patient has not met the criteria for NF2, he is now considered as an asymptomatic subject at risk and observed. Lens opacities with epiretinal membranes in children may be regarded as part of the clinical manifestation of NF2.
Leptospirosis: possibilities of early laboratory and clinical diagnosis
Authors: Cermakova Zuzana , Kucerova Petra , Valenta Zbynek , Pliskova Lenka , Bolehovska Radka , Prasil Petr , Buchta Vladimir , Scharfen Josef , Polak Pavel , Pavlis Ota , Voxova Barbora 
Published: November 2012

Abstract
This retrospective study aims to identify and describe the problems associated with the laboratory and clinical diagnosis of leptospirosis. A total of 4,813 patients with suspected leptospirosis from an area of the Czech Republic, with a total population of 1.15 million, were examined during the period 2002–2010. Our study included only 855 patients: 545 men (mean age 41.03 ± 19.24) and 310 women (mean age 41.47 ± 20.3) who were examined using microscopic agglutination test (MAT) and a polymerase chain reaction (PCR). All patients and their physicians filled in questionnaires, which included anamnestic data, clinical symptoms and the results of laboratory tests. Out of total suspected, 89 patients (1.85%), tested positive for leptospirosis, of which 50 have been examined only serologically by MAT. Of 855 patients in our study undergoing both PCR and MAT tests, 39 have tested positive for leptospirosis. The most frequent symptom in patients with leptospirosis included fever (91.6%) and headache (69.4%). The correct laboratory diagnosis of leptospirosis depends on biological material being tested before the start of antibiotic treatment, since leptospires are extremely sensitive to antibiotics. Consequently, the PCR results alone may produce a false negative result after 24 hours following treatment with antibiotics.
Apical barrier technique using MTA: report of two cases
Authors: Sharma A , Krishna A , Hans M , Shetty S , Dahiya S 
Published: November 2012

Open apices of pulpless immature teeth have always posed a problem as they need to be sealed before they are obturated. In recent years MTA has gained popularity as it provides a single step apical plug and thus helps in apexification. This article reports two cases which were successfully treated with MTA which had open apices. Health Renaissance; September-December 2012; Vol 10 (No.3);239—241 DOI: http://dx.doi.org/10.3126/hren.v10i3.7054
Diagnostic dialemma in diagnosing acute monoarthritis and mono articular rheumatoid arthritis of right elbow in a 24 year old young lady
Authors: Chaudhary P , Shrestha BP , Khanal GP , Rijal R , Karn NK , Maharjan R , Sinha AK 
Published: November 2012

Acute monoarthritis can be the initial manifestation of many joint disorders. The first step in diagnosis is to verify that the source of pain is the joint, not the surrounding soft tissues. The most common causes of monoarthritis are crystals (i.e., gout and pseudo gout), trauma, and infection. Here, we present a case of 24-year-old young lady who had presented to the Orthopaedic depatment of B.P.Koirala Institute of Health Sciences, Dharan, Nepal with pain,swelling and restriction of movement of right elbow for 3 days. With all these characteristics and literature reviewed, we thought that this case unique and rare and needs to be reported. Health Renaissance; September-December 2012; Vol 10 (No.3);244-250 DOI: http://dx.doi.org/10.3126/hren.v10i3.7056
Therapeutic Levels of Lopinavir in Late Pregnancy and Abacavir Passage into Breast Milk in the Mma Bana Study, Botswana
Authors: Shapiro Roger L , Rossi Steven , Ogwu Anthony , Moss Mary , Leidner Jean , Moffat Claire , Lockman Shahin , Moyo Sikhulile , Makhema Joseph , Essex Max , Capparelli Edmund 
Published: November 2012

Background Pharmacokinetic data for lopinavir in late pregnancy and in breastfeeding are limited, and no data for abacavir in breast milk are available. Methods Women in the Mma Bana Study initiated HAART from 18 to 34 weeks of gestation. We determined trough plasma and whole breast milk concentrations of lopinavir (LPV), abacavir (ABC), nevirapine (NVP), lamivudine (3TC) and zidovudine (ZDV) among separate subsets of pregnant and breastfeeding women, and in plasma of exposed infants. Lopinavir was measured 1 month after starting HAART or 1 month postpartum, and other drugs were measured 1 month postpartum. Results Sampling occurred a median of 14 h (range 11–17) from last maternal drug ingestion. Although 50% higher median LPV levels were seen in postpartum than antepartum plasma (8.29 μg/ml versus 5.51 μg/ml; P=0.02), antepartum levels with standard LPV dosing were therapeutic for all women (>1.0 μg/ml). Very low LPV levels (<0.25 μg/ml) were detected in breast milk. Median ABC levels in breast milk were 85% of those in plasma (0.057 μg/ml versus 0.067 μg/ml). Breast milk concentrations of NVP and 3TC were 27% and 74% of plasma levels, respectively. At these trough maternal time points, only NVP was detectable in potentially inhibitory levels in breastfeeding infants, and most infants had non-detectable levels of LPV, ABC, ZDV and 3TC via maternal breast milk. Conclusions Standard LPV dosing achieved therapeutic levels in pregnancy and no appreciable concentrations in breast milk. ABC is detectable in breast milk at similar concentrations to plasma, but does not result in appreciable infant exposure.
La performance en question
Authors: Bichüe Didier 
Published: November 2012

Résumé La performance, « cheval de bataille » de nos dirigeants appliqué au secteur médico-social par le biais de l’agence nationale d’appui à la performance ( anap ), est-elle à redouter ou à adopter ? Quelles sont les différentes représentations de la performance selon la place que nous occupons dans le système de l’aide aux personnes ? Quels sont les enjeux économiques et culturels qui sous-tendent ces nouveaux modes d’organisation dans lesquels on veut nous entraîner ?
Performance et reprise en main de l'État : les raisons d'une obsession comptable
Authors: Loubat Jean-René 
Published: November 2012

Résumé L’arrivée de ce nouveau « gros mot » dans l’univers de l’action sociale et médico-sociale – c’est-à-dire externe à sa culture historique – brise un tabou fondamental : celui de l’utilité même de ses dispositifs, de leurs véritables objectifs et de leur efficacité. Performance et efficience s’inscrivent dans une logique historique de reprise en main par l’État de la destinée de tels secteurs, dans une logique vitale de maîtrise des dépenses publiques imposée par un contexte de déclin démographique et économique durable de l’Europe.
Recherche et « performance » en travail social
Authors: Leplay Éliane 
Published: November 2012

Résumé La performance peut être définie comme le constat de réussite d’une action. Dans le champ du travail social, la construction des objectifs ne s’effectue pas de la même façon que dans une activité de production ; il s’agit ici d’une activité de coproduction du service avec les bénéficiaires du service. La dimension clinique de cette activité impose la prise en compte du sujet individuel et/ou collectif, dans un processus qui s’inscrit dans le temps. La recherche en travail social peut éclairer ces questions en étudiant les activités « réelles » de travailleurs sociaux, dans leur environnement. L’intelligibilité de ces pratiques dans toute leur complexité peut constituer une base utile, voire nécessaire à la construction de modes d’évaluation pertinents.
Performance et impératifs gestionnaires : quels enjeux pour la condition professionnelle des travailleurs sociaux ?
Authors: Saint-Martin Corinne 
Published: November 2012

Résumé Les impératifs gestionnaires soumettent les travailleurs sociaux à une transformation de leur cadre de travail, modifient leurs ressources professionnelles. Nous appuyant sur une enquête sociologique menée après la catastrophe industrielle toulousaine de 2001, nous montrons comment le travail social s’organise, les stratégies mises en place pour maintenir l’activité et son sens. Il apparaît qu’un important « travail invisible » – tant sur l’organisation que relationnel – opère ; il a cependant permis de générer des solutions créatives. aujourd’hui, c’est ce travail qui interroge. Que deviennent ces savoir-faire professionnels face aux « épreuves » de la performance ?
Des éthiques de la responsabilité pour penser l'évaluation en éducation et en formation
Authors: Beauvais Martine 
Published: November 2012

Résumé Du champ de la formation à celui de la santé en passant par le travail social, l’évaluation envahit toutes les sphères de notre quotidien. Que nous la subissions en tant que sujet-objet, ou que nous la conduisions en tant qu’auteur-acteur, l’évaluation engage notre responsabilité et questionne notre rapport à l’Autre, au monde et à nous-mêmes. Cet article pose les jalons d’une réflexion éthique de la responsabilité en éducation et en formation et suggère des clés de lecture « bricolées » à partir de principes philosophiques plutôt maximalistes.
Ethnobotanical review of food uses of Polygonatum (Convallariaceae) in China
Authors: Wujisguleng Wujisguleng , Liu Yujing , Long Chunlin 
Published: November 2012

According to our literature survey, fifteen species in the genus <em>Polygonatum </em>(Convallariaceae) have been used as food in China. Five main categories of use (drinks, snacks, vegetables, staple food and seasoning) were found. The plants from this genus are used mainly as vegetables. Rhizomes are the main parts used. The categories of use and diverse preparation methods have some similarities with those in other countries. Among all the recorded species, <em>Polygonatum sibiricum </em>and <em>P. odoratum </em>are the most commonly consumed species in China. Local people from different places have their own unique preparation methods and customs. However, the use of <em>Polygonatum </em>still remains at the level of family consumption, and the resources have not been fully used yet. We proposed ideas for further exploitation and conservation of edible <em>Polygonatum </em>species, and suggested fur- ther research, e.g. on the nutritional properties of all recorded edible species. It is believed that there is still plentiful traditional knowledge about food uses of <em>Polygonatum </em>to be documented in China.
Marking 100 years since Rudolf Höber’s discovery of the insulating envelope surrounding cells and of the β-dispersion exhibited by tissue
Authors: Pethig Ronald , Schmueser Ilka 
Published: November 2012

Abstract
Between 1910 and 1913 Rudolf Höber presented proof that the interiors of red blood cells and muscle cells contain conducting electrolytes, and that each conducting core is contained within an insulating membrane. He did this by demonstrating, in a series of remarkable electrical experiments, that the conductivity of compacted cell samples at low frequencies (~150 Hz) was about ten-times less than the value obtained at ~5 MHz. On perforation of the membrane, the low-frequency conductivity increased to a value approaching that exhibited at MHz frequencies. Apart from representing a major milestone in the development of cell biology and electrophysiology, Höber’s work was the first description of what we now call the dielectric β-dispersion exhibited by cell suspensions and fresh tissue.