bluuebunny/crossref_metadata_2025 huggingface dataset:
Functions of C2D macrophage cells after adoptive transfer
Authors: Potts Betsey E , Chapes Stephen K
Published: December 2007

Macrophage function depends on their in situ location. To test this hypothesis, we examined functional changes of the C2D macrophage cell line after adoptive transfer. In vitro, C2D macrophages reside early in the macrophage lineage and show little functional activity. After in vivo i.p. culture, C2D macrophage cells switch their cytokine/chemokine profile from primarily Th2 cytokines produced in vitro to a Th1 profile including MIP-1α, IL-6, and TNF-α. The in vivo environment also caused C2D macrophage cells to become more phagocytic than their in vitro counterparts. These data indicate that C2D macrophage cells exhibit distinct functions because of in vivo signals that are absent during in vitro culture.
Intravascular inactivation of CCR5 byn-Nonanoyl-CC chemokine ligand 14 and inhibition of allergic airway inflammation
Authors: Gupta Shipra , Fuchs Barbara , Schulz-Maronde Sandra , Heitland Aleksandra , Escher Sylvia E , Mack Matthias , Tillmann Hanns-Christian , Braun Armin , Forssmann Wolf-Georg , Elsner Jörn , Forssmann Ulf
Published: December 2007

Modulation of leukocyte recruitment through intervention with chemokine receptors is an attractive, therapeutic strategy. Recently, we have shown that n-Nonanoyl (NNY)-CCL14 internalizes and desensitizes human (h)CCR3, resulting in the inactivation of eosinophils. In this study, we investigated the interaction of NNY-CCL14 with CCR1 and CCR5 and the relevance of these NNY-CCL14 receptors on its in vivo effects in allergic airway inflammation. NNY-CCL14 has inactivating properties on CCR1+ and CCR5+ cell lines and primary leukocytes. It desensitizes hCCR1- and hCCR5-mediated calcium release and internalizes these receptors from the cellular surface. Treatment of OVA-sensitized BALB/c mice with NNY-CCL14 resulted in reduced pulmonary inflammation. Above all, it is demonstrated that systemic treatment with NNY-CCL14 down-modulates CCR5 from the surface of lymphocytes in vivo. Although NNY-CCL14 acts on murine lymphocytes and internalizes CCR5, it does not internalize CCR3 on mouse eosinophils, showing species selectivity regarding this particular receptor. Therefore, the inhibitory effects of NNY-CCL14 in murine models of allergic airway inflammation can be assigned to its interaction with CCR5. The presented results substantiate the relevance of CCR5 as a target for allergic airway inflammation.
Hope and Prognostic Disclosure
Authors: Mack Jennifer W. , Wolfe Joanne , Cook E. Francis , Grier Holcombe E. , Cleary Paul D. , Weeks Jane C.
Published: December 2007

Purpose

Physicians sometimes selectively convey prognostic information to support patients’ hopes. However, the relationship between prognostic disclosure and hope is not known.

Patients and Methods

We surveyed 194 parents of children with cancer (overall response rate, 70%) in their first year of treatment at the Dana-Farber Cancer Institute and Children's Hospital (Boston, MA), and we surveyed the children's physicians. We evaluated relationships between parental recall of prognostic disclosure by the physician and possible outcomes, including hope, trust, and emotional distress. Our main outcome was assessed by asking parents how often the way the child's oncologist communicated with them about the children's cancers made them feel hopeful.

Results

Nearly half of parents reported that physician communication always made them feel hopeful. Parents who reported receiving a greater number of elements of prognostic disclosure were more likely to report communication-related hope (odds ratio [OR], 1.77 per element of disclosure; P = .001), even when the likelihood of a cure was low (OR, 5.98 per element of disclosure with likelihood of a cure < 25%; P = .03). In a multivariable model, parents were more likely to report that physician communication always made them feel hopeful when they also reported receipt of more elements of prognostic disclosure (OR, 1.60; P = .03) and high-quality communication (OR, 6.58; P < .0001). Communication-related hope was inversely associated with the child's likelihood of cure (OR, 0.65; P = .005).

Conclusion

Although physicians sometimes limit prognostic information to preserve hope, we found no evidence that prognostic disclosure makes parents less hopeful. Instead, disclosure of prognosis by the physician can support hope, even when the prognosis is poor.
Nuclear Receptor Agonists Improve Insulin Responsiveness in Cultured Cardiomyocytes through Enhanced Signaling and Preserved Cytoskeletal Architecture
Authors: Montessuit Christophe , Papageorgiou Irène , Lerch René
Published: December 2007

Insulin resistance is the failure of insulin to stimulate the transport of glucose into its target cells. A highly regulatable supply of glucose is important for cardiomyocytes to cope with situations of metabolic stress. We recently observed that isolated adult rat cardiomyocytes become insulin resistant in vitro. Insulin resistance is combated at the whole body level with agonists of the nuclear receptor complex peroxisome proliferator-activated receptor γ (PPARγ)/retinoid X receptor (RXR). We investigated the effects of PPARγ/RXR agonists on the insulin-stimulated glucose transport and on insulin signaling in insulin-resistant adult rat cardiomyocytes. Treatment of cardiomyocytes with ciglitazone, a PPARγ agonist, or 9-cis retinoic acid (RA), a RXR agonist, increased insulin- and metabolic stress-stimulated glucose transport, whereas agonists of PPARα or PPARβ/δ had no effect. Stimulation of glucose transport in response to insulin requires the phosphorylation of the signaling intermediate Akt on the residues Thr308 and Ser473 and, downstream of Akt, AS160 on several Thr and Ser residues. Phosphorylation of Akt and AS160 in response to insulin was lower in insulin-resistant cardiomyocytes. However, treatment with 9-cis RA markedly increased phosphorylation of both proteins. Treatment with 9-cis RA also led to better preservation of microtubules in cultured cardiomyocytes. Disruption of microtubules in insulin-responsive cardiomyocytes abolished insulin-stimulated glucose transport and reduced phosphorylation of AS160 but not Akt. Metabolic stress-stimulated glucose transport also involved AS160 phosphorylation in a microtubule-dependent manner. Thus, the stimulation of glucose uptake in response to insulin or metabolic stress is dependent in cardiomyocytes on the presence of intact microtubules.
Side Population Does Not Define Stem Cell-Like Cancer Cells in the Adrenocortical Carcinoma Cell Line NCI h295R
Authors: Lichtenauer Urs D. , Shapiro Igor , Geiger Klaus , Quinkler Marcus , Fassnacht Martin , Nitschke Roland , Rückauer Klaus-Dieter , Beuschlein Felix
Published: December 2007

Recent evidence suggests the existence of a stem cell-like subpopulation of cells in hematological and solid tumor entities, which determine the malignant phenotype of a given tumor through their proliferative potential and chemotherapy resistance. A recently used technique for the isolation of this cell population is through exclusion of the vital dye Hoechst 33342, which defines the so-called side population (SP). Herein we demonstrate the presence of SP cells in a variety of adrenal specimens, including primary cultures of human adrenocortical tumors and normal adrenal glands as well as established human and murine adrenocortical cancer cell lines by fluorescence-activated cell sorter analysis and confocal microscopy. On a functional level, SP cells from the human adrenocortical tumor cell line NCI h295R revealed an expression pattern consistent with a less differentiated phenotype, including lower expression of steroidogenic enzymes such as steroid acute regulatory protein (StAR) and side-chain cleavage enzyme (P450scc) in comparison with non-SP cells. However, proliferation between SP and non-SP cells did not differ (105.6 ± 18.1 vs. 100.0 ± 3.5%). Furthermore, re-sorting and tracing experiments revealed the capacity for both cell types to give rise to the original SP- and non-SP-containing cell population. Similarly to the baseline growth kinetics, no survival benefit was evident in SP cells after treatment with cytotoxic agents commonly used in adrenocortical carcinomas. Taken together, these findings provide evidence that Hoechst dye exclusion, in contrast to what has been reported for other tumor entities, is not a major tumor stem cell defining marker in adrenocortical NCI h295R tumor cells.
Activation of SRC Kinase and Phosphorylation of Signal Transducer and Activator of Transcription-5 Are Required for Decidual Transformation of Human Endometrial Stromal Cells
Authors: Nagashima Takashi , Maruyama Tetsuo , Uchida Hiroshi , Kajitani Takashi , Arase Toru , Ono Masanori , Oda Hideyuki , Kagami Maki , Masuda Hirotaka , Nishikawa Sayaka , Asada Hironori , Yoshimura Yasunori
Published: December 2007

Progesterone induces decidual transformation of estrogen-primed human endometrial stromal cells (hESCs), critical for implantation and maintenance of pregnancy, through activation of many signaling pathways involving protein kinase A and signal transducer and activator of transcription (STAT)-5. We have previously shown that kinase activation of v-src sarcoma (Schmidt-Ruppin A-2) viral oncogene homolog (SRC) kinase is closely associated with decidualization and that SRC is indispensable for maximal decidualization in mice. To address whether SRC kinase activity is essential for decidualization in humans, hESCs were infected with adenoviruses carrying enhanced green fluorescent protein alone (Ad-EGFP), a kinase-inactive dominant-negative mutant (Ad-SRC/K295R), or an inactive autophosphorylation site mutant (Ad-SRC/Y416F). The cells were cultured in the presence of estradiol and progesterone (EP) to induce decidualization and subjected to RT-PCR, immunoblot, and ELISA analyses. Ad-EGFP-infected hESCs exhibited decidual transformation and up-regulation of decidualization markers including IGF binding protein 1 and prolactin in response to 12-d treatment with EP. In contrast, hESCs infected with Ad-SRC/K295R remained morphologically fibroblastoid without production of IGF binding protein 1 and prolactin even after EP treatment. Ad-SRC/Y416F displayed similar but less inhibitory effects on decidualization, compared with Ad-SRC/K295R. During decidualization, STAT5 was phosphorylated on tyrosine 694, a well-known SRC phosphorylation site. Phosphorylation was markedly attenuated by Ad-SRC/K295R but not Ad-EGFP. These results indicate that the SRC-STAT5 pathway is essential for decidualization of hESCs.
Melatonin Stimulates the Release of Growth Hormone and Prolactin by a Possible Induction of the Expression of Frog Growth Hormone-Releasing Peptide and Its Related Peptide-2 in the Amphibian Hypothalamus
Authors: Chowdhury Vishwajit S. , Yamamoto Kazutoshi , Saeki Izumi , Hasunuma Itaru , Shimura Taichi , Tsutsui Kazuyoshi
Published: December 2007

We recently identified a novel hypothalamic neuropeptide stimulating GH release in bullfrogs and termed it frog GH-releasing peptide (fGRP). The fGRP precursor encodes fGRP and its related peptides (fGRP-RP-1, -RP-2, and -RP-3), and fGRP-RP-2 also stimulates GH and prolactin (PRL) release. Cell bodies and terminals containing these neuropeptides are localized in the suprachiasmatic nucleus (SCN) and median eminence, respectively. To understand the physiological role of fGRP and fGRP-RP-2, we investigated the mechanisms that regulate the expression of these neuropeptides. This study shows that melatonin induces the expression of fGRP and fGRP-RPs in bullfrogs. Orbital enucleation combined with pinealectomy (Ex plus Px) decreased the expression of fGRP precursor mRNA and content of mature fGRP and fGRP-RPs in the diencephalon including the SCN and median eminence. Conversely, melatonin administration to Ex plus Px bullfrogs increased dose-dependently their expressions. The expression of fGRP precursor mRNA was photoperiodically controlled and increased under short-day photoperiods, when the nocturnal duration of melatonin secretion increases. To clarify the mode of melatonin action on the induction of fGRP and fGRP-RPs, we further demonstrated the expression of Mel1b, a melatonin receptor subtype, in SCN neurons expressing fGRP precursor mRNA. Finally, we investigated circulating GH and PRL levels after melatonin manipulation because fGRP and fGRP-RP-2 stimulate the release of GH and GH/PRL, respectively. Ex plus Px decreased plasma GH and PRL concentrations, whereas melatonin administration increased these hormone levels. These results suggest that melatonin induces the expression of fGRP and fGRP-RP-2, thus stimulating the release of GH and PRL in bullfrogs.
Phosphorylation-Dependent Sumoylation Regulates Estrogen-Related Receptor-α and -γ Transcriptional Activity through a Synergy Control Motif
Authors: Tremblay Annie M. , Wilson Brian J. , Yang Xiang-Jiao , Giguère Vincent
Published: December 2007

Interplay between different posttranslational modifications of transcription factors is an important mechanism to achieve an integrated regulation of gene expression. For the estrogen-related receptors (ERRs) α and γ, regulation by posttranslational modifications is still poorly documented. Here we show that transcriptional repression associated with the ERR amino-terminal domains is mediated through sumoylation at a conserved phospho-sumoyl switch, ψKxEPxSP, that exists within a larger synergy control motif. Arginine substitution of the sumoylatable lysine residue or alanine substitution of a nearby phosphorylatable serine residue (serine 19 in ERRα) increased the transcriptional activity of both ERRα and -γ. In addition, phospho-mimetic substitution of the serine residue with aspartate restored the sumoylation and transcriptional repression activity. The increased transcriptional activity of the sumoylation-deficient mutants was more pronounced in the presence of multiple adjacent ERR response elements. We also identified protein inhibitor of activated signal transducer and activator of transcription y as an interacting partner and a small ubiquitin-related modifier E3 ligase for ERRα. Importantly, analysis with a phospho-specific antibody revealed that sumoylation of ERRα in mouse liver requires phosphorylation of serine 19. Taken together, these results show that the interplay of phosphorylation and sumoylation in the amino-terminal domain provides an additional mechanism to regulate the transcriptional activity of ERRα and -γ.
Waiting Lists and the Demand for Public Housing
Authors: Gregory Peter
Published: December 2007

Although local authorities in Britain set great store by ‘housing lists’ it is well known that these lists are inadequate in many ways, and they only provide a very imperfect measure of housing need. For instance housing lists may exaggerate the real demand for public housing because they will include some people who have no immediate desire for accommodation – and indeed some with no real intention of ever occupying council property, but who are merely using the list as an ‘insurance policy’. This is particularly likely to occur in a city like Hull which maintains an ‘open’ list that is one to which entry is not restricted by income, existing tenure, residence or other limitations.

Also, housing lists may underestimate the needs of some even though the needs of others are inflated. Clearly those local authorities who refuse places on the list to single people below retirement age, working couples without children, and owner-occupiers may be excluding many with genuine housing needs. Even local authorities like Hull with open lists must assess which proportion of the people in need do actually apply for council accommodation.
Can You Cut a Budget Pie?
Authors: Clark Terry Nichols
Published: December 2007

How assess a study which shows, for example, that city police expenditures increased and fire expenditures were held constant? Or how respond to a public official who asks how better to allocate a budget? Can we systematize, at least partially, such elusive concepts as the ‘quality of life’? Consultants may comment, with varying success, from personal experience and ideology. Others may undertake cost-benefit analyses. This paper considers procedures which can bring more sophistication to traditional cost-benefit work. A first step is adequate conceptualization of public policy outputs. One basic dimension is who benefits?

To answer who benefits from public policy one can analyze correspondence between a policy and the value configurations of different social sectors in the affected population. Here we define a sector as benefiting from a policy insofar as the policy is consistent with the sector’s values. Thus the greater the disparity between a policy and a sector’s values, the less the sector benefits. Sectors are defined by whatever criteria (income, political party, etc.) are significant in the social unit in question.

Crucial to answering who benefits, therefore, are precise conceptualization and measurement of values. These issues we consider first.
Social Deprivation and Performance at School
Authors: Wilson Harriett , Herbert G. W.
Published: December 2007

The policy of positive discrimination in favour of areas of acute social need has resulted in a number of studies which concern themselves with methods of identification. Hatch and Sherrott found that deprivations are concentrated only to a limited extent, and that for this reason an index summarising a range of deprivations is not efficient, They suggest that a multi-dimensional approach might be indicated because different combinations of deprivations are found in different areas needing a variety of remedies. Barnes, in discussing the work done for the Inner London Education Authority, points out that the majority of disadvantaged children is to be found in areas not classified as priority, and that the majority of children in priority areas is not disadvantaged. Little and Mabey show that the reading achievement of disadvantaged children (unskilled and semi-skilled manual) does not vary as much in relation to either the social mix of the school or the degree of priority of the area as that of less disadvantaged pupils. The methods identifying deprivation are diverse and largely related to either objective criteria (absence of basic housing amenities, free school meals, etc.) or vulnerable groups (one-parent families, immigrants, unskilled, etc.).
Planning the Social Services: The Local Authority Ten Year Plans
Authors: Webb Adrian , Falk Nicholas
Published: December 2007

One of the consequences of the Seebohm inspired reorganisation of the personal social services has been a marked increase in the attention and resources directed to management and planning within the local authority social service departments. One suspects that, at least in terms of speed and scale of its development, this outcome of reorganisation was an unexpected one. Nevertheless, policy decisions have encouraged the trend, none more so perhaps than the request made by the Department of Health and Social Security in August 1972 that local authorities should prepare plans covering their personal social service capital and revenue programmes for the period 1 April 1973 to 31 March 1983. In one sense the circular Department of Health and Social Security 35/72 represents a resumption of the ten year planning processes for health and community care initiated in 1963, but it can equally be seen as a new milestone in the development of the post-Seebohm services. The new planning process offers an opportunity to exploit administrative changes that have taken place in both the local authorities and in the National Health Service: it marks a changing relationship between the Department of Health and Social Security (hereafter referred to as the Department) and local authority departments.
Elected Representatives in a Party System: A Typology
Authors: Corina Lewis
Published: December 2007

In the widespread complaints about the prevalence of party influence in local government there is a recognizable stereotyping of local politicians and parties which is a caricature of the complex reality. The purposes of this paper are to question the validity of the stereotypes and to suggest the abandonment of simplistic categories in favour of categories which go some way at least towards recognizing the complex variables which shape the role-playing of elected members.

What follows is based on a ten year period of participant-based research in an urban county borough council. Material from this specific study was supplemented by participant observation in a new county council and by observation-based research in two other boroughs. Participant research is a technique which creates a number of problems, the most formidable being that the researcher is a ‘partisan’ role-player in the ongoing local authority activities. In Halifax (the first-mentioned urban authority) this was not a great problem because the context was influenced by a three-party system in which the ongoing decisionmaking was tripartite and, indeed, occasionally multi-partite.
Social Class, Educational Attainment, and Provision: An LEA Case Study
Authors: King Ronald
Published: December 2007

Studies of social class differences in educational attainment form the core of what is now being called the orthodox sociology of education in this country. Most of the sociological explanations of the higher rates of middle class success have been variants of a ‘culture clash’ or ‘cultural discontinuity’ theory. This has taken many forms, including the use of the idea of deferred gratification, associated with Schneider and Lysgaard, the Protestant ethic, used by Cohen and Hargreaves, basic value-orientations, as used by Sugarman, and perhaps the most sophisticated version, the sociolinguistic theory of Bemstein. This kind of explanation has been recently criticized by sociologists using a phenomenological approach as representing deficit system thinking; the image of the working class child as lacking the internal social wherewithal to succeed.

In addition, Bryne and Williamson have recently brought into the sociological arena a theory that has quite a long history in the literature of social policy and elsewhere. This is the ‘differential provision theory’, which can be summarized in the following three propositions: a. Working class children have a poorer material provision, b. Educational attainment is positively related to material provision, and c. The social class differences in educational attainment are (partly) explained by the differences in provision.
Metamorfoze Preservation Microfilming Guidelines
Authors: Dormolen Hans van
Published: December 2007

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Brown, Heather. Training in Preservation Microfilming
Authors: Maidment Ewan
Published: December 2007

Heather Brown writes in her introduction to
Book Reviews
Authors: Wagner Lauren
Published: December 2007

North African Women in France: Gender, Culture, and Identity. Caitlin Killian. Stanford, CA: Stanford University Press. 2006. 279 pages. ISBN 0804754209 (cloth); 0804754217 (paper).
Eugene Island Block 330 Field-- Development and Production History
Authors: Lewis Ronald L. , Dupuy Harvey J.
Published: December 2007

Eugene Island Block 330 field is currently the largest oil- producing field in federally owned offshore waters of the U.S. The field is located about 170 miles southwest of New Orleans (Fig. 1). The first leases were purchased in Dec. 1970. Three months later, a major discovery was apparent when exploratory wells drilled by Pennzoil and Shell on adjoining Blocks 330 and 331, respectively, established a 900-ft column of hydrocarbon-bearing sands. By the end of 1971, two platforms had been set, and development was under way. Four more platforms were set during 1972 and ultimately nine platforms were installed in the field. Initial production began in Sept. 1972 from Block 331.

Hydrocarbon accumulation occurs in more than 25 sandstone reservoirs located at 2.200 to 12,000 ft. Recoverable reserves are estimated to be greater than 225 million bbl of liquid hydrocarbons and 950 Bcf of gas. Improved recovery operations began in Aug. 1975, utilizing water injection on Blocks 331 and 314 and through-gas injection in Dec. 1979 on Block 330. Through Dec. 1982, cumulative production was 224 million bbl of liquid and 1.03 Tcf of gas. This production is graphically illustrated in Figs. 2 and 3. This field is unique in the quick timing of operations to develop and initiate production.

Introduction

Eugene Island 330 field consists of portions of seven U.S. government lease blocks of 5,000 acres each as illustrated in Fig. 4. Operators are Exxon (2 blocks). Pennzoil (2 blocks), Shell Oil Co. (1 block), and Texaco Inc. (2 blocks).

Several other operators having, interests jointly with Pennzoil are Exxon Corp., Mesa Petroleum Co., Mobil Corp., Pogo Producing Co.. Texas Production Co. and its subsidiaries, Pinto Inc. and Ecee Inc. Tenneco Inc. has interest jointly with Texaco in Block 338.

This paper discusses the total geological complex and then follows the development and production history of the primary block, Eugene Island Block 330.

Exploration

Early exploration of the Eugene Island Block 330 area followed the Dec. 1970 offshore lease sale. Exploratory drilling began in Feb. 1971. By Oct. 1971, sufficient successful exploratory wells had been drilled to determine locations for five platforms. Subsequent exploratory and development drilling proved the necessity of four more platforms. As shown in Fig. 4, there have been 26 exploratory wells drilled and 9 eight-pile drilling and production platforms and 4 four-pile satellite production platforms set.

Geology

The field is an anticlinal structure on the downthrown side of a large arcuate-trending growth fault.

JPT

P. 1956^
Report on MWD Experimental Downhole Sensors
Authors: Grosso Donald S. , Raynal Jean C. , Rader Dennis
Published: December 2007

Measurement while drilling (MWD) provides a means for monitoring drilling and formation parameters as drilling progresses. The technique, based on the use of advanced downhole sensor and telemetry technology, makes possible the real-time acquisition of data that was previously impossible without stopping the drilling previously impossible without stopping the drilling operation. Some downhole data, such as weight and torque on bit (WOB and TOB) can be obtained only while drilling.

In Summer 1976, Teleco Oilfield Services began an experimental program to demonstrate the feasibility and usefulness of a multisensor MWD tool for real-time measurement of drilling mechanics, formation evaluation, and well-control parameters. A package incorporating six sensors was designed and implemented in a downhole tool capable of transmitting data to the surface by means of mud-pulse telemetry.

In this paper we discuss the experimental 6-sensor tool and representative results obtained in a series of 12 field tests in various pails of the world, both onshore and offshore.

Introduction

The MWD tool was introduced in Aug. 1976 on a limited basis. It was designed to provide the directional-drilling industry with real-time measurements of hole deviation, azimuth, and tool facing. Full commercial directional service was made available in the Gulf of Mexico and the North Sea in Sept. 1978. In a parallel effort begun in 1976, an experimental system was built to demonstrate the broader potential of down hole MWD technology for enhancing the safety and efficiency of dulling while simultaneously obtaining formation-evaluation data. Two prototype MWD tools incorporating six downhole sensors and using mud-pulse telemetry were built. More than 1,200 hours of continuous mud-pulse data transmission were accumulated in the field test program.

Telemetry System

Mud-pulse telemetry is a wireless means of communicating data from downhole to the surface. Information in the form of binary bits is communicated through a sequence of pressure pulses generated in the mud column within the drill pipe by a valve located in a special sub near the bit. This information, in the form of pressure waves, propagates through the drilling mud and is detected and displayed at the surface. This technique imposes no restrictions on the drilling operation, is rugged, reliable, safe, and only marginally affected by mud composition or depth.

So far, MWD technology has been applied primarily to directional surveying. Its use in other applications, such as formation evaluation and drilling efficiency, offers great promise to the oil and gas well drilling industry. In the balance of this paper, some of these applications are discussed on the basis of an extensive series of tests with the experimental six-sensor MWD tool. Additional discussions of MWD technology and applications are found in Refs. 1 through 4.

The essential elements of the telemetry system consist of the transmitter and surface receiving equipment.

JPT

P. 899
Surfactant Retention in Berea Sandstone— Effects of Phase Behavior and Temperature
Authors: Novosad J.
Published: December 2007

Experimental procedures designed to differentiate between surfactant retained in porous media because of adsorption and surfactant retained because of unfavorable phase behavior are developed and tested with three types of surfactants. Several series of experiments with systematic changes in one variable such as surfactant/cosurfactant ratio, slug size, or temperature are performed, and overall surfactant retention then is interpreted in terms of adsorption and losses caused by unfavorable phase behavior.
Low-Permeability Laboratory Measurements by Nonsteady-State and Conventional Methods
Authors: Freeman David Louis , Bush Darrell Cleo
Published: December 2007

Evaluation of tight gas reservoirs requires an accurate but rapid and practical method to determine permeability. Such a method is presented for determining both specific and effective gas permeability in the 0.0001- to 0.35-md range for plug-size core samples.

Equipment is described that meets the requirements for calculation of nonsteady-state flow and incorporates the capability of simulating high net overburden pressures by either hydrostatic or triaxial confining pressures with ease of operation. The time required to collect data and calculate Klinkenberg permeability is typically less than 6 minutes per sample. Values normally differ by less than ±5% from those obtained by steady-state methods. This method is well suited for routine laboratory determinations of permeability on samples from reservoirs with tight or very low gas permeability.

Effective gas permeabilities on samples containing nearly irreducible water saturations and the water permeabilities presented are closer to the Klinkenberg permeability values in low-permeability samples than most previously reported.
Production Behavior of Prolific Gas Wells and Optimal Production Policy for a Gas-Reservoir Complex
Authors: Dietz D.N. , Scholten P. , Wilms H.
Published: December 2007

A new and simple decline formula facilitates the search for an optimal policy of production with or without compressers from a number of gas reservoirs of different characteristics. Optimizing production policy traditionally is carried out by trial and error. The paper leaves this procedure essentially unaltered but reduces the computer time per trial, thus allowing more trials. Results of some sample calculations are presented.

Introduction

Where numerous wells producing from several as reservoirs feed into a common pipeline system, a great number of alternative production policies present themselves, especially where gas has to be compressed to bring it up to pipeline pressure. To study the alternatives one needs the basic information regarding performance of the individual wells. To describe such performance one may choose among several formulas available in the literature, which are all based on the assumption that, apart from pressures. the physical conditions remain unchanged. A prudent prediction. however, will allow for possible deterioration or even complete loss of one or more wells. On the other hand, one is at liberty, of course, to postulate replacement and infill drilling. Performance of a future producer has to be estimated. Hence the combined performance of all wells in a single gas reservoir can be predicted with only limited accuracy.

Once this unavoidable inaccuracy is accepted we must conclude that it is not justified and not desirable to waste computer capacity on excessively accurate well production performances-, computer capacity is employed more usefully on a large number of alternative production policies.

This philosophy is worked out in the following chapters. For the time being, we have limited ourselves to reservoirs, without water drive.

Performance and Decline

Traditionally, inflow performance is defined as the dependence of production rate on bottomhole pressure (BHP). At low rates Darcy's law prevails and the inflow expressed at standard conditions is described by

q = C (p2-pw2) (1)

This formula is obtained by assuming that the gas has a constant viscosity and follows Boyle's law.

At higher rates the flow becomes turbulent in the proximity of the well. There is an upstream section with a linear resistance and a downstream one with a quadratic resistance This leads to

(2)Aq+Bq2=p2-pw2

This well-known formula is not exact, because the higher the rate, the longer the section with a quadratic resistance.

JPT

P. 2285^
Generalized Theory for Evolution and Dispersion of H2S From Alkaline Muds
Authors: Wendt Richard P.
Published: December 2007

This paper develops a general theory to describe the evolution and dispersion of H2S from alkaline drilling mud into which CH4, H2S, and CO2 have intruded downhole. The theory is based on an assumed general form for the electrical neutrality condition between all dissolved ionic species. Also assumed operative are mass-action laws for the several sulfide and carbonate species and Henry's law for the partial pressure of CO2 and H2S above the mud. These constraints and a modified form of the Pasquill-Gifford equation are then used to calculate H2S levels at any position downwind from the wellhead. Required input variables for the calculation include the initial pH and Pm of the mud, the mud flow rate, total gas intrusion rate, and mole fraction of H2S and CO2 in the intruding gas. The theory provides a rational model for estimating effects of these variables on gaseous H2S levels downwind and indicates severe limitations on the alkaline method for controlling sour gas intrusions.
Economic Factors in Bank Loans on Oil and Gas Production
Authors: Dodson Charles R. , McGee John S.
Published: December 2007

Introduction

As is now well known, oil producers borrow from banks for operating and capital purposes, including the development and purchase of producing properties. Sound bank loans on oil and gas producing properties depend on a thorough analysis and correct evaluation of numerous credit considerations. These can be segregated, for convenience, into five major groups: management, engineering, legal, regulatory and economic.

All are important to banks. Heretofore, only management and engineering, and to a lesser extent, legal and regulatory considerations have been popular topics for analysis. Purely economic considerations appear to have received too little publicity.

Consequently, our purpose here is to remedy this situation in part by the discussion of several of the important economic considerations and to explain why we think they are important. However, before proceeding we should first review the nature and requirements of commercial banking in order to understand why lending officers must consider these economic factors.

Banker's Point of View

Bank officers are prudent and enterprising business men, capable of evaluating potential loans in the light of the bank's lending and liquidity policies. Bankers respect and honor the requests and needs of their customers who have established banking relationships; i.e., those who have used credit, deposit and other bank services. In the case of loan applications from new customers, the banker is interested in the long-run potentiality for a growing relationship in regard to deposits and use of bank services as well as future loans. A banker has in mind not only his obligations to stockholders and depositors, but also the legal requirements and the relatively low rate of return on loans. Further, the bank must help the borrower to avoid difficulties and accomplish efficiently his financial objectives. Frequently, businessmen do not fully appreciate these obligations and restrictions or realize that these are applicable to oil loans.

The petroleum industry is a complicated giant composed of many interrelated segments - producing, transportation, refining and marketing - which are vital to our economy. As we hope to show later, the industry regardless of its huge size is not independent of or isolated from the national economy. If this is true then sound loans in the oil producing segment require not only a thorough and current knowledge of the industry, but a "feel" for economics as well. This is equally important to the borrower in order to tailor a loan that properly fits his needs and capacity to repay as promised.
Multiphase Dispersion and Relative Permeability Experiments
Authors: Delshad M. , MacAllister D. J. , Pope G. A. , Rouse B. A.
Published: December 2007

Experiments in both Berea sandstone and sandpacks have been conducted to measure dispersion and steady-state relative permeabilities. Measurements have been made on both high-tension brine/oil and a low-tension, three-phase, brine/oil/surfactant/alcohol mixture. One interesting aspect of these experiments is the amount of microemulsion phase trapping. The endpoint microemulsion saturations for both the oil/microemulsion and brine/micro-emulsion phase pairs were high even at 10−3 dyne/cm [10−3 mN/m] interfacial tension (IFT). The dispersion was measured for each phase with radioactive and chemical tracers. The dispersivity was found to be a strong function of phase, phase saturation, porous medium, and IFT. Values of the dispersivity varied by two orders of magnitude over conditions investigated to date. Extremely early breakthrough of the tracer used in the oil phase (carbon 14) at high tension is especially remarkable. The brine tracer (tritium) curves were similar to that for 100% brine saturation except for a shift caused by material balance reasons. The classical solution to the convection-diffusion equation for single-phase flow has been generalized to multiphase flow and was used to aid in interpreting these data. This combination of relative permeability and dispersion in each phase of the experiment with a high-concentration, three-phase-microemulsion sulfonate formulation is believed to be new, and more directly applicable to commercial surfactant flooding than previously reported experimental results.
The Thermal Recovery Process - An Analysis of Laboratory Combustion Data
Authors: Benham A.L. , Poettman Fred H.
Published: December 2007

By considering the stoichiometry of the underground combustion process, an equation was derived relating the point velocity of the combustion front as a function of the air flux, fuel content, efficiency of oxygen utilization, hydrogen:carbon ratio, and ratio of carbon dioxide to carbon monoxide produced. In addition, an equation for calculating the amount of injected air necessary to produce the oil from 1 cu ft of reservoir space was derived. This equation has a direct bearing on evaluating compression costs for the process. Values calculated from these equations are in good agreement with experimentally observed values obtained from laboratory tube runs reported in the literature. The equations are also useful for analyzing experimental data for inconsistencies.

Introduction

The injection of energy in the form of heat into an oil-bearing formation as a means of increasing the recovery of oil has been the subject of much discussion and experimentation as far back as 1920. The ideas have ranged from the injection of steam to the direct use of electricity as a means of getting thermal energy into a formation.

However, most laboratory and field studies have been confined to the process whereby a portion of the crude in the reservoir is burned to generate the necessary heat to increase the mobility of the oil by reducing its viscosity. A recent paper by W. L. Martin, et al. described the results of a number of laboratory experiments in which the combustion process was studied in a sandpack. Studies such as this indicate that with the temperatures involved, the oil is partially coked in this process and it is this coke which provides the fuel for combustion. The combustion of this residual coke can be analyzed theoretically by applying simple stoichiometric principles to the combustion process.

It is the purpose of this paper to compare the results reported in these experiments with those obtained from theoretical considerations.
Porosity Balance Verifies Water Saturation Determined From Logs
Authors: Tixier M.P.
Published: December 2007

In several log interpretation methods, water saturation is evaluated by use of the ratio of the readings of a short spacing resistivity device and a long spacing resistivity device plus information on the mud filtrate and connate water resistivities, which is often derivable from the SP. These methods are valid over a certain range of conditions, usually specified by moderate invasion and Rxo greater than Rt. Since these methods involve no explicit evaluation of the formation factor, F, the saturation so found may be used in the standard Archie equation to derive a computed formation factor which, as a check, may be compared with the formation factor known from other independent measurements. Discrepancies in the two values of formation factor generally indicate that the ratio method is not within its range of applicability. If the computed F is too low, the corresponding Sw is too low; if the computed F is too great, the corresponding Sw is too great. By means of this "porosity balance" check, and some knowledge of the probable conditions of invasion, the interpretation can often be improved.

The porosity balance check is discussed for the cases of the Induction-Electrical Log Interpretation Method, the Rocky Mountain Method, and the Rxo/Rt Method. For the first method, a discussion is also given for the case of shaly sands.

Introduction

Although many logging tools are available to obtain a practical value of porosity, the only logging method reflecting the water saturation is electrical logging.

Water saturation is commonly computed from electrical log data by means of the basic Archie formula,

(Equation 1)

where F is the formation factor, Rw the resistivity of the formation water, and Rt the true resistivity of the formation.

One difficulty in this procedure is a possible error in the evaluation of Rt from the logs - for example, in the case of very deep invasion. There is no possibility, inherent in the procedure, which would provide a check of the accuracy of Rt and, hence, of the computed saturation.
Pipe Viscometer Study of Fracturing Fluid Rheology
Authors: Rogers Rudy E. , Veatch Ralph W. , Nolte Kenneth G.
Published: December 2007

The large increase in the use of crosslinked fracturing fluids in the past decade has led to the need for accurate evaluation of their flow properties. Traditional rotational viscometers are inadequate for studying the rheology of these crosslinked fracturing fluids, hereafter called "gels." A recently developed coiled-pipe viscometer is described, and gel response to various temperature and shear histories during preparation and testing is presented as determined by the pipe viscometer.

If gel flow properties in the fracture are to be studied accurately with any viscometer, then preparation of the gel, thermal energy input, and mechanical energy input to the test sample should be controlled to duplicate the gel of the fracture. The pipe viscometer developed has the following attributes.

Gel preparation is an integral part of the viscometer. Each element of the gel is subjected to the same degree of shear while mixing. The gel develops in-line as it moves to the test section of the viscometer. There are no stagnant periods. Heat transfer occurs from the walls of the conduit to the fluid in flow as in the fracture. Parallel flow sections are incorporated for scale-up information.

Results are presented to elucidate the mechanism of gel formation and deterioration, gel stability at high temperatures, and the possible occurrence of slip flow in the fracture. The coiled-pipe viscometer shows potential to stimulate fluid preparation and flow in the fracturing process.
Migration of Alkaline Pulses in Reservoir Sands
Authors: Bunge A. L. , Radke C. J.
Published: December 2007

Establishing the amount of alkali loss by rock reactions is critical because successful application of most alkaline flooding techniques requires that hydroxide propagate through a large portion of the reservoir. This paper presents a mathematical analysis of the chromatographic movement of alkaline pulses when they are scaled to reservoir flow rates and distances. Using only this analysis and laboratory data, we show how to estimate the distance an alkaline pulse traverses under field conditions before its concentration diminishes to ineffective levels.

Laboratory core tests and X-ray analyses identify the various mineral reactions and their rates. For clayey sands a fast, reversible, sodium/hydrogen ion exchange retards alkali concentration velocities. Fine silica and quartz are suggested as important dissolving minerals, with slower-dissolving clays and clay minerals releasing soluble aluminum, which may redeposit with soluble silica as new aluminosilicate minerals. While new mineral formation influences the aqueous aluminum and silica concentrations, hydroxide consumption appears to be controlled mainly by the dissolution reaction. First-order kinetics most closely represent the dissolution behavior; lumped-parameter rate constants are reported for Huntington Beach and Wilmington sands and for a Berea sandstone.
Computing Thermal Neutron Decay Time Environmental Effects Using Monte Carlo Techniques
Authors: Preeg W. E. , Scott H. D.
Published: December 2007

Time-dependent, three-dimensional (3D), coupled-neutron/gamma-ray Monte Carlo calculations were made for both thermal neutron decay time (TDT-K™ and TDT-M™) logging systems. Calculations were made for different borehole sizes, casing sizes, and different formation and borehole macroscopic capture cross sections (Σ). Good agreement was obtained between our calculations and laboratory TDT measurements.

Monte Carlo calculations were made to separate the contributions to the detector count rates resulting from gamma rays produced in various regions, such as the borehole fluid, casing, cement, and those produced in the formation. The decay rates resulting from these various components show how the measured Σ may differ from the intrinsic formation Σ and lead to a better understanding of the relationship between the near- and far- detector measurements. The calculations also provide information on the bed-thickness response of the TDT.