bluuebunny/crossref_metadata_2025_split huggingface dataset:
Heat Management in Steam floods Without the Use of Temperature Observation Wells
Authors: Haroun Muhammad , Ershaghi Iraj 
Published: March 2008

Abstract
Heat management to reduce operational cost requires drilling of and routine monitoring of temperature obsrervation wells. There are cases where because of economics and environmental restrictions, drilling of observation wells may not be feasible or practical. The particular point of focus are some heavy oil reservoirs such as those in the Middle East where the drilling of observation wells are cost prohitive. Using advances in downhole sensors for continous recordings of temperatures in producing wells, one can track the average in-situ temperatures from the production and the injection temperatures and use those estimates as a monitoring tool. Relating producing well's temperatures to average reservoir temperature and injection temperature may be done, depending on the well placement and reservoir geometry, through various formulations such as the Lauwerier1 or the Marx Langenheim2. Characteristics of heavy oil viscosity-temperature correlations can then serve as a basis to select producing temperatures when one can reduce steam input to levels that maintain the required fluid temperatures in the reservoir without overdoing the heat input. Optimum injection rates and incremental heat input into the reservoir can be estimated such that the temperature of produced fluid is maintained at a pre-set condition. We have tested the concept and feasibility of the proposed method with a commercial simulator, for oil gravities ranging from 10 - 14 °API.
Case-Based Reasoning Approach for Well Failure Diagnostics and Planning
Authors: Popa Andrei , Popa Carrie , Malamma Mike , Hicks John 
Published: March 2008

Abstract
Case-based reasoning, also known as computer reasoning by analogy, is a simple and practical technique that solves new problems by comparing them to ones that have already been solved in the past, thus saving time and money. The technique constantly incorporates dynamic data, which empowers the system to learn and adapt from new experiences. A general framework for case-based reasoning is presented, along with a review of the four-step cycle that characterizes the technology: retrieve, reuse, revise and retrain.
This paper presents a specific application of case-based reasoning to determine the optimum cleaning technique (bailing, washback, or foaming) for sanded/seized well failures. The methodology extracts only the most relevant information from the historical database, utilizes a rule-based system to make adaptations, and then suggests the most appropriate solution for a given well intervention. This technique was used for production operations as a front end tool for well workover planning and design and was applied to sample data from a large oil field where the main artificial lift system is rod pump. This simple case demonstrates how case-based reasoning can be applied to improve the planning and execution of well interventions, thus reducing cost, rig time, and well turnaround time, while maximizing reliability and production.
Disclosure-Disciplining Mechanisms: Capital Markets, Product Markets, and Shareholder Litigation
Authors: Evans John H. , Sridhar Sri S. 
Published: March 2008

This paper demonstrates that a firm's trade-offs between reporting good news to reduce the cost of capital and bad news to minimize proprietary costs can induce the firm's manager to provide truthful disclosures when the opposing effects balance each other. We also show that greater proprietary costs can make a firm's disclosures more credible, increase the frequency of voluntary adverse disclosures, and improve the disclosing firm's welfare.
Further, we find that potential shareholder litigation can interact with capital and product markets' influences to make voluntary disclosures more credible, but only under certain circumstances. For example, although product market competition can complement the capital market effects in inducing the manager to provide truthful disclosures, shareholder litigation cannot complement the capital market in the same way. Nevertheless, while shareholder litigation can never induce misreporting, a very strong product market influence can prompt a firm to underreport its true economic condition.
Auditor Negotiations: An Examination of the Efficacy of Intervention Methods
Authors: Trotman Ken T. , Wright Arnold M. , Wright Sally 
Published: March 2008

Negotiations are a pervasive feature of the audit process (e.g., the resolution of proposed audit adjustments and disclosures). The results of such negotiations are of great importance to the capital markets, the client, and the auditor. The purpose of this study is to examine the effectiveness of three promising, pragmatic intervention methods for enhancing auditor negotiation performance: a role-playing intervention—assuming the client's position in a mock negotiation; a passive intervention—explicitly considering the client's interests and options; and a practice intervention—engaging in a mock negotiation prior to the client negotiation. We posit that the role-playing intervention will improve negotiation results, because this approach requires direct experience in considering and arguing the client's position and more cognitive effort in obtaining an understanding of the counterpart's position, a critical factor identified in the negotiation literature for successful performance.Forty-five audit managers and partners were provided a realistic case based on an actual scenario involving the potential writedown of inventory due to obsolescence. Participants were randomly assigned to one of three groups (role-playing, passive, or practice) and asked to negotiate the issue with a confederate playing the role of the CFO. Auditor conservatism and a large actual subsequent writedown suggest that a significant adjustment is warranted. The results indicate that the role-playing intervention method led to an enhanced negotiation outcome (greater writedown) compared to the passive and practice groups. Process improvements on a number of dimensions were also found, particularly for the role-playing group compared to the practice group.
The Importance of Circulating and Presenting Manuscripts: Evidence from the Accounting Literature
Authors: Brown Lawrence D. 
Published: March 2008

Editors exhort authors to circulate and present their working papers to colleagues before submitting them to journals (Zimmerman 1989; Green et al. 2002). Authors heeding such advice are said to increase the likelihood of getting their work published and making their research, once published, more influential (Zimmerman 1989). While evidence regarding these matters is of keen importance to authors, editors, and administrators, no research exists showing that circulating and presenting manuscripts increases their probability of being accepted in accounting journals or, when published, their influence on stimulating other research. I present such evidence by perusing acknowledgments in premier accounting journals.I examine the relation between circulating and presenting manuscripts and the probability of acceptance by relating acknowledgments of 305 papers submitted to The Accounting Review during June 2002–May 2003 to the editor's reject versus revise and resubmit decision. I examine the relation between circulating and presenting manuscripts and an article's influence by relating the acknowledgments in 256 articles published in The Accounting Review, Journal of Accounting Research, and Journal of Accounting and Economics to citations to these articles.My two analyses of acknowledgments to institutions, conferences, and individuals yield similar results. I find that papers presented at more workshops are more likely to be invited back to The Accounting Review, and that papers published in The Accounting Review, Journal of Accounting and Economics, or Journal of Accounting Research generate more citations if they were presented previously at more workshops.
Metformin Decreases the Adipokine Vaspin in Overweight Women With Polycystic Ovary Syndrome Concomitant With Improvement in Insulin Sensitivity and a Decrease in Insulin Resistance
Authors: Tan Bee K. , Heutling Dennis , Chen Jing , Farhatullah S. , Adya Raghu , Keay Stephen D. , Kennedy C. Richard , Lehnert Hendrik , Randeva Harpal S. 
Published: March 2008

OBJECTIVE—Polycystic ovary syndrome (PCOS) is associated with insulin resistance and obesity. Vaspin (visceral adipose tissue–derived serine protease inhibitor) levels increase with hyperinsulinemia and obesity. Currently, no data exists on vaspin in PCOS women. We therefore assessed mRNA and protein levels of vaspin, including circulating vaspin, from subcutaneous and omental adipose tissue of PCOS women and matched control subjects. Ex vivo regulation of adipose tissue vaspin and the effects of metformin treatment on circulating vaspin levels in PCOS subjects were also studied.
RESEARCH DESIGN AND METHODS—Real-time RT-PCR and Western blotting were used to assess mRNA and protein expression of vaspin. Serum vaspin was quantified by enzyme-linked immunosorbent assay. The effects of d-glucose, insulin, and gonadal and adrenal steroids on adipose tissue vaspin were analyzed ex vivo.
RESULTS—There were significantly higher levels of circulating vaspin (P &lt; 0.05), vaspin mRNA (P &lt; 0.05), and protein (P &lt; 0.05) in omental adipose tissue of PCOS women. Interestingly, in omental adipose tissue explants, glucose significantly increased vaspin protein levels and secretion into conditioned media (P &lt; 0.001). Also, after 6 months of metformin treatment, there was a significant decrease in serum vaspin levels in PCOS women (P &lt; 0.001). Furthermore, multivariate regression analysis revealed that following metformin therapy, changes in circulating glucose levels were predictive of changes in serum vaspin levels (P = 0.014).
CONCLUSIONS—We report, for the first time, elevated serum and omental adipose tissue levels of vaspin in overweight PCOS women and ex vivo regulation of vaspin, predominantly by glucose. More importantly, metformin treatment decreases serum vaspin levels, a novel observation.
New Markers of Oxidative Damage to Macromolecules
Authors: Čolak Emina 
Published: March 2008

New Markers of Oxidative Damage to Macromolecules
The presence of free radicals in biological material has been discovered some 50 years ago. In physiological conditions, free radicals, in the first place the ones of oxygen and nitrogen, are continuously synthesized and involved in the regulation of a series of physiological processes. The excess of free radicals is efficiently eliminated from the body in order to prevent their toxic effects. Toxic effects of free radicals may be classified into three groups: a) change of intracellular redox potential, b) oxidative modification of lipids, proteins and DNA, and c) gene activation. Lipid peroxidation involving cell membranes, lipoproteins and other molecules leads to the production of primary high-reactive intermediaries (alkyl radicals, conjugated dienes, peroxy- and alkoxyl radicals and lipid hydroperoxide), whose further breakdown generates the secondary products of lipid peroxidation: short-chain evaporable hydrocarbons, aldehydes and final products of lipid peroxidation: isoprostanes, MDA, 4-hydroxy-2, 3-transnonenal and 4,5-dihydroxydecenal which are important mediators of atherosclerosis, coronary disease, acute myocardial infarction, rheumatoid arthritis, systemic sclerosis and lupus erythematodes. Oxidative modification of proteins is manifested by changes in their primary, secondary and tertiary structures. Proteins have a specific biological function, and therefore their modification results in unique functional consequences. The nature of protein modification may provide valid information on the type of oxidants causing the damage. Chlorotyrosyl is a specific marker of oxidative damage to tyrosine caused by HOCl action, which most commonly reflects the involvement of neutrophils and monocytes in oxidative stress, while nitrotyrosyl indicates the presence of higher peroxy-nitrite synthesis. Methyonin and cysteine are the amino acids most sensitive to oxidative stress, carbonyl groups are markers of severe damage caused by free radicals, and di-tyrosyl is the most significant and sensitive marker of oxidative modification made by γ rays. >Carbonyl stress< is an important form of the secondary oxidation of proteins, where reducing sugars non-enzymatically react with amino groups of proteins and lipids and give rise to the production of covalent compounds known as advanced glycosylated end products (AGE-products). A hydroxyl radical damages the DNA, leading to a loss of base and the formation of abasic sites (AP sites), break of DNA chain and sugar modification. Final lipid peroxidation products (MDA) may covalently bind to DNA, producing the >DNA radicals< which are responsible for mutations. Measurement of an adequate oxidative stress biomarker may not only point to an early onset of disease, its progression and assessment of therapy effectiveness, but can also help in the clarification of the pathophysiological mechanisms of tissue damage caused by oxidative stress, prediction of disease prognosis and choice of appropriate treatment in the early stages of disease.
Microsite variation and climate result in stand dynamics variation in pristine Pinus sylvestris mires: Evidence from a stand structure study
Authors: Sarkkola Sakari , Hökkä Hannu , Penttilä Timo 
Published: March 2008

AbstractQuestions: How do climate conditions and the site's ecohy‐ drological properties affect the age and size structure of natural Pinus sylvestris stands on pristine boreal mires? How do the long‐term stand dynamics on mires proceed as stands age? Do the mire stands reach a balanced, old‐growth stage?Location: Boreal mire forests in southern and northern Finland.Methods: Tree age and diameter distributions were analysed in 52 stands in two climate areas and in two mire site types with different ecohydrological properties. Temporal stand dynamics were examined by (1) comparing the graphs of the stands’ mean tree ages by diameter at breast height (1.3 m) classes and (2) describing the changes in stand characteristics and stand age and size structures as a function of stand dominant age in a chronosequence.Results: In the south, the DBH distributions were mostly unimodal and bell‐shaped in both site type groups. Age distributions were multimodal and flat in fully‐stocked sites but more uneven in sparsely forested composite sites. In the north, both the age and size distributions were clearly uneven in both site type groups. Tree age and size variation increased with stand age, but levelled out in the long term. Particularly in the south, the abundance of small trees decreased as stand age increased.Conclusions: The pine stands on pristine boreal mires are more dynamic than anticipated and are generally not characterised by a balanced, self‐perpetuating structure. Their dynamics reflect differences in climate and ecohydrology: on stocked sites in favourable boreal conditions, the stands showed structures typically resultant of inter‐tree competition processes that control tree growth and regeneration, whereas in harsh boreal climates, the tree regeneration process is ongoing diversifying the stand structure.
Evaluation of nanoparticle dispersion in polypropylene by small‐angle X‐ray scattering
Authors: Lipp Jonathan , Makarov Carina , Khalfin Rafail L. , Shuster Michael , Berenstein Larissa , Melamed Ofira , Odani Ayelet , Zaban Arie , Cohen Yachin 
Published: March 2008

AbstractA small‐angle X‐ray scattering method has been developed for the quantitative evaluation of the effectiveness of nanoparticle dispersion in polymer matrices; it is termed the nanoscale dispersion index. This method was applied to dispersions of nanosized TiO2 fillers in polypropylene. Master batches prepared with lower filler contents showed better dispersion as evaluated by the nanoscale dispersion index. The addition of 1,3:2,4‐di(3,4‐dimethylbenzylidene) sorbitol to the compounds did not affect the degree of nanoscale dispersion as estimated by the nanoscale dispersion index. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Preparation of polyurethane nanofibers by electrospinning
Authors: Zhuo Haitao , Hu Jinlian , Chen Shaojun , Yeung Lapyan 
Published: March 2008

AbstractPolyurethane (PU) nanofibers were prepared by the electrospinning method. The process parameters, including the applied voltage, feeding rate, and solution concentration, were investigated carefully. The results showed that the resultant nanofibers, electrospun from PU/N,N‐dimethylformamide (DMF) solutions, had ultrafine diameters ranging from about 700 to 50 nm. In addition, it was found that the diameters and morphology of the nanofibers were influenced greatly by the process parameters. In particular, the solution concentration played a main role in influencing the transformation of the polymer solution into ultrafine fibers, and the diameters increased with the solution concentrations increasing. Finally, it was concluded that uniform PU nanofibers without beads or curls could be prepared by electrospinning through good control of the process parameters, such as 5.0–7.0 wt % PU/DMF solutions, 10–15‐kV applied voltages, and 0.06–0.08 mm/min feeding rates. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Endocranial Occipito‐Temporal Anatomy of SD‐1219 from the Neandertal El Sidrón Site (Asturias, Spain)
Authors: Rosas Antonio , Peña‐Melián Angel , García‐Tabernero Antonio , Bastir Markus , De La Rasilla Marco , Fortea Javier 
Published: March 2008

AbstractWe addressed the brain drainage system as inferred by the endocranial morphology of the occipito‐temporal region of the El Sidrón Neandertal specimen SD‐1219. Morphological details of the endocranial surface and its anatomical implications were analyzed for the reconstruction of the dural sinus drainage pattern and its comparison with Neandertals and other hominids. The specimen SD‐1219 shows a pattern in which the superior sagittal sinus goes into the right transverse sinus. Comparative analyses with a large sample of fossil hominids reveal a pattern of the SD‐1219 fossil that is typical for Neandertals. The analysis of the proportions of the occipital lobes prints within the occipital fossae reveals that the left occipital pole projects toward the right. This possibly indicates brain asymmetry (petalia) in this Neandertal individual, similar to that observed in some modern human brains. Conversely, no such asymmetry was observed in the cerebellar fossae. A particular feature of this fossil is the presence of two crests, located at the middle of the left cerebellar fossa that can be related to either an imprinting of a cerebellar fissure or some bone response to mechanical influence on internal bone surface morphology during cerebellar development. Specific aspects of the paleoneurology of Neandertals are discussed. Further quantitative studies on the endocranial morphology of the occipito‐temporal and ‐mastoid region will shed light on the paleoneurological significance of this important anatomical region for the understanding of human evolution. Anat Rec, 291:502–512, 2008. © 2008 Wiley‐Liss, Inc.
A Novel Genetic Selection System for Improved Enantioselectivity of Bacillus subtilis Lipase A
Authors: Boersma Ykelien L. , Dröge Melloney J. , van der Sloot Almer M. , Pijning Tjaard , Cool Robbert H. , Dijkstra Bauke W. , Quax Wim J. 
Published: March 2008

AbstractIn directed evolution experiments, success often depends on the efficacy of screening or selection methods. Genetic selections have proven to be extremely valuable for evolving enzymes with improved catalytic activity, improved stability, or with altered substrate specificity. In contrast, enantioselectivity is a difficult parameter to select for. In this study, we present a successful strategy that not only selects for catalytic activity, but for the first time also for enantioselectivity, as demonstrated by the selection of Bacillus subtilis lipase A variants with inverted and improved enantioselectivity. A lipase mutant library in an aspartate auxotroph Escherichia coli was plated on minimal medium that was supplemented with the aspartate ester of the desired enantiomer (S)‐(+)‐1,2‐O‐isopropylidene‐sn‐glycerol. To inhibit growth of less enantioselective variants, a covalently binding phosphonate ester of the opposite (R)‐(−)‐1,2‐O‐isopropylidene‐sn‐glycerol enantiomer was added as well. After three selection rounds in which the selection pressure was increased by raising the phosphonate ester concentration, a mutant was selected with an improved enantioselectivity increased from an ee of −29.6 % (conversion 23.4 %) to an ee of +73.1 % (conversion 28.9 %) towards the (S)‐(+)‐enantiomer. Interestingly, its amino acid sequence showed that the acid of the catalytic triad had migrated to a position further along the loop that connects β7 and αE; this shows that the position of the catalytic acid is not necessarily conserved in this lipase.
Density Functional Studies on Palladium‐Catalyzed Suzuki–Miyaura Cross‐Coupling Reactions Assisted by N‐ or P‐Chelating Ligands
Authors: Huang Yi‐Luen , Weng Chia‐Ming , Hong Fung‐E. 
Published: March 2008

AbstractDFT studies with the B3LYP functional have been carried out on the Suzuki–Miyaura cross‐coupling reactions of phenyl chloride and phenylboronic acid catalyzed by palladium complexes with N‐ or P‐chelating ligands. The full catalytic cycle, from the addition of reactants to the catalyst to the release of the cross‐coupled product from the complexed intermediate, has been examined. The stages within the cycle, such as oxidative addition, transmetalation, and reductive elimination, were validated by linking the mechanistically relevant intermediates and transition states. Various derivatives of diimine, diphosphine, and diamine were considered as potential model ligands. The catalytic reaction employing diimine as the chelating ligand has been verified as the one with the most energetically feasible route.
ChemInform Abstract: Efficient Photoluminescence of Dy3+ at Low Concentrations in Nanocrystalline ZrO2.
Authors: Diaz‐Torres L. A. , De la Rosa E. , Salas P. , Romero V. H. , Angeles‐Chavez C. 
Published: March 2008

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Study on the Solid Solution of YMn1‐xFexO3: Structural, Magnetic and Dielectric Properties.
Authors: Samal S. L. , Green W. , Lofland S. E. , Ramanujachary K. V. , Das D. , Ganguli A. K. 
Published: March 2008

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Tetrahedral Tellurate.
Authors: Konaka Saki , Ozawa Yoshiki , Yagasaki Atsushi 
Published: March 2008

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.