bluuebunny/crossref_metadata_2025_split huggingface dataset:
Core Scale Fracture Characterisation in Deviated Wells Aid Multiple Jurassic Reservoir Development in Minagish Field, West Kuwait
Authors: Verma Naveen Kumar , Al Shamali Adnan Aiesh , AL-Mayyas Eman Abdullah , Dasma Mohammed , Al-Khamis Waleed Khamis 
Published: December 2009

Abstract
Unconventional fractured Najmah-Sargelu (NJ-SR) and tight carbonates of Middle Marrat constitute Jurassic reservoirs in Minagish Field. Although NJ-SR oil was discovered in mid-eighties, reservoir development remains a challenge in this field where exploratory delineation wells have been drilled until 2002. The reservoir characterisation difficulties in this unconventional fractured reservoir include large well spacing, field compartmentalization, low resolution seismic and oil based well logs besides drilling problems. Therefore, understanding of the productivity controls is primarily based on the image logs and core data collected in vertical exploratory or Marrat development wells. Based on these data in Minagish and adjoining fields, supplemented with seismic facies analysis for identifying sub-seismic ‘fracture corridors’, a regional 3D Discrete Fracture Network model (DFN) was built for West Kuwait in 2004. It thus became feasible to place a Marrat well through NJ-SR fractured area or even to intercept a fracture corridor using a deviated well profile. Yet, since the model was largely conceptual, a quantitative validation was planned through acquisition of NJ-SR core in such wells, followed by core orientation using Goniometry technique and detailed core to image log fracture calibration to understand relationship between large and small scale features and their role in productivity.
First such deviated well was successfully drilled near a fracture corridor and cored using ‘half-moon’ core barrel technology despite repeated core jamming. Core was oriented using goniometry technique and striking parallelism was observed between the image log based and core based fractures. However, the well could not be tested in NJ-SR and was completed in Marrat based on reservoir considerations. Similar core-based fracture characterization was successfully done in second such deviated well that traversed through a deformation zone further away from a fracture corridor. The well has recently been tested and produced oil from NJ-SR reservoir fulfilling combined objectives of appraisal and development of multiple Jurassic reservoirs. Present paper provides a detailed account of these fracture characterization efforts through goniomentry and core to image log calibration for understanding the productivity controls, and discusses further well design optimization possibilities.
Interaction Between Flexible Risers and Mooring Lines within a Floating Production System
Authors: Brown Paul Anthony , Larsen Ian , Chandwani Ramesh , Dasambiagio Evandro Rossi 
Published: December 2009

ABSTRACT
In any semisubmersible-type or turret-moored tanker-type floating production system (FPS) it is essential to consider interaction between the flexible riser system and mooring system or anchor spread. This is necessary in order to ensure that there is adequate clearance between mooring lines and the closest riser at all depths and that cross-over of lines is avoided. This is a particular problem in supergiant fields utilising many flexible risers, for example the large Campos Basin fields offshore Brasil. Furthermore, a quantitative evaluation of the total dynamic load imposed on the vessel due to the riser system is required for assessment of station keeping and stability and for structural design.
This paper demonstrates simultaneous dynamic analysis of flexible riser and mooring systems for a complete FPS. The FPS studied uses a semisubmersible type vessel located in deep water. The vessel is kept on station using a 12-point mooring system. The riser system utilises flexible pipe technology and all risers are designed using a "lazy wave" configuration. The system is subjected to both operational and extreme wave conditions. The effect of variable current direction with depth, which is common offshore Brasil, is demonstrated. The coupled effect of pipe-seabed friction is also demonstrated.
R&D Delegation in a Duopoly with Spillovers
Authors: Versaevel Bruno , Vencatachellum Désiré 
Published: December 2009

Abstract
There is evidence that competing firms outsource R&D to the same independent for-profit laboratory. We draw on this stylized fact to construct a model where two firms in the same industry offer transfer payments in exchange for user-specific R&D services from a common laboratory. Inter-firm and within-laboratory externalities affect the intensity of competition among delegating firms on the intermediate market for technology. Whether competition is relatively soft or tight is reflected by each firm's monetary offers to the laboratory. These offers determine the R&D outcomes, the laboratory's capacity to earn benefits, the profits for the delegating firms, as well as social welfare. We identify the situations in which the laboratory finds it profitable to deliver services to only one firm, or to both of them. In the latter case we compare the delegated R&D game to two other ones where firms conduct in-house R&D, either cooperatively or non-cooperatively. The delegated R&D game Pareto dominates the other two games, and the laboratory earns positive benefits, if and only if R&D services are complementary inside the laboratory, but only limitedly so, and inter-firm spillovers are sufficiently low. The firms' privately-profitable decision to delegate R&D, when the laboratory participates, always benefits consumers.
Inhibition of PTP1B Restores IRS1-Mediated Hepatic Insulin Signaling in IRS2-Deficient Mice
Authors: González-Rodríguez Águeda , Gutierrez Jose A. Mas , Sanz-González Silvia , Ros Manuel , Burks Deborah J. , Valverde Ángela M. 
Published: December 2009

OBJECTIVE
Mice with complete deletion of insulin receptor substrate 2 (IRS2) develop hyperglycemia, impaired hepatic insulin signaling, and elevated gluconeogenesis, whereas mice deficient for protein tyrosine phosphatase (PTP)1B display an opposing hepatic phenotype characterized by increased sensitivity to insulin. To define the relationship between these two signaling pathways in the regulation of liver metabolism, we used genetic and pharmacological approaches to study the effects of inhibiting PTP1B on hepatic insulin signaling and expression of gluconeogenic enzymes in IRS2−/− mice.

RESEARCH DESIGN AND METHODS
We analyzed glucose homeostasis and insulin signaling in liver and isolated hepatocytes from IRS2−/− and IRS2−/−/PTP1B−/− mice. Additionally, hepatic insulin signaling was assessed in control and IRS2−/− mice treated with resveratrol, an antioxidant present in red wine.

RESULTS
In livers of hyperglycemic IRS2−/− mice, the expression levels of PTP1B and its association with the insulin receptor (IR) were increased. The absence of PTP1B in the double-mutant mice restored hepatic IRS1-mediated phosphatidylinositol (PI) 3-kinase/Akt/Foxo1 signaling. Moreover, resveratrol treatment of hyperglycemic IRS2−/− mice decreased hepatic PTP1B mRNA and inhibited PTP1B activity, thereby restoring IRS1-mediated PI 3-kinase/Akt/Foxo1 signaling and peripheral insulin sensitivity.

CONCLUSIONS
By regulating the phosphorylation state of IR, PTB1B determines sensitivity to insulin in liver and exerts a unique role in the interplay between IRS1 and IRS2 in the modulation of hepatic insulin action.
Detailed Investigation of the Role of Common and Low-Frequency WFS1 Variants in Type 2 Diabetes Risk
Authors: Fawcett Katherine A. , Wheeler Eleanor , Morris Andrew P. , Ricketts Sally L. , Hallmans Göran , Rolandsson Olov , Daly Allan , Wasson Jon , Permutt Alan , Hattersley Andrew T. , Glaser Benjamin , Franks Paul W. , McCarthy Mark I. , Wareham Nicholas J. , Sandhu Manjinder S. , Barroso Inês 
Published: December 2009

OBJECTIVE
Wolfram syndrome 1 (WFS1) single nucleotide polymorphisms (SNPs) are associated with risk of type 2 diabetes. In this study we aimed to refine this association and investigate the role of low-frequency WFS1 variants in type 2 diabetes risk.

RESEARCH DESIGN AND METHODS
For fine-mapping, we sequenced WFS1 exons, splice junctions, and conserved noncoding sequences in samples from 24 type 2 diabetic case and 68 control subjects, selected tagging SNPs, and genotyped these in 959 U.K. type 2 diabetic case and 1,386 control subjects. The same genomic regions were sequenced in samples from 1,235 type 2 diabetic case and 1,668 control subjects to compare the frequency of rarer variants between case and control subjects.

RESULTS
Of 31 tagging SNPs, the strongest associated was the previously untested 3′ untranslated region rs1046320 (P = 0.008); odds ratio 0.84 and P = 6.59 × 10−7 on further replication in 3,753 case and 4,198 control subjects. High correlation between rs1046320 and the original strongest SNP (rs10010131) (r2 = 0.92) meant that we could not differentiate between their effects in our samples. There was no difference in the cumulative frequency of 82 rare (minor allele frequency [MAF] &lt;0.01) nonsynonymous variants between type 2 diabetic case and control subjects (P = 0.79). Two intermediate frequency (MAF 0.01–0.05) nonsynonymous changes also showed no statistical association with type 2 diabetes.

CONCLUSIONS
We identified six highly correlated SNPs that show strong and comparable associations with risk of type 2 diabetes, but further refinement of these associations will require large sample sizes (&gt;100,000) or studies in ethnically diverse populations. Low frequency variants in WFS1 are unlikely to have a large impact on type 2 diabetes risk in white U.K. populations, highlighting the complexities of undertaking association studies with low-frequency variants identified by resequencing.
Lack of Lipotoxicity Effect on β-Cell Dysfunction in Ketosis-Prone Type 2 Diabetes
Authors: Umpierrez Guillermo E. , Smiley Dawn , Robalino Gonzalo , Peng Limin , Gosmanov Aidar R. , Kitabchi Abbas E. 
Published: December 2009

OBJECTIVE
Over half of newly diagnosed obese African Americans with diabetic ketoacidosis (DKA) discontinue insulin therapy and go through a period of near-normoglycemia remission. This subtype of diabetes is known as ketosis-prone type 2 diabetes (KPDM).

RESEARCH DESIGN AND METHODS
To investigate the role of lipotoxicity on β-cell function, eight obese African Americans with KPDM, eight obese subjects with type 2 diabetes with severe hyperglycemia without ketosis (ketosis-resistant type 2 diabetes), and nine nondiabetic obese control subjects underwent intravenous infusion of 20% intralipid at 40 ml/h for 48 h. β-Cell function was assessed by changes in insulin and C-peptide concentration during infusions and by changes in acute insulin response to arginine stimulation (AIRarg) before and after lipid infusion.

RESULTS
The mean time to discontinue insulin therapy was 11.0 ± 8.0 weeks in KPDM and 9.6 ± 2.2 weeks in ketosis-resistant type 2 diabetes (P = NS). At remission, KPDM and ketosis-resistant type 2 diabetes had similar glucose (94 ± 14 vs. 109 ± 20 mg/dl), A1C (5.7 ± 0.4 vs. 6.3 ± 1.1%), and baseline AIRarg response (34.8 ± 30 vs. 64 ± 69 μU/ml). P = NS despite a fourfold increase in free fatty acid (FFA) levels (0.4 ± 0.3 to 1.8 ± 1.1 mmol/l, P &lt; 0.01) during the 48-h intralipid infusion; the response to AIRarg stimulation, as well as changes in insulin and C-peptide levels, were similar among obese patients with KPDM, patients with ketosis-resistant type 2 diabetes, and nondiabetic control subjects.

CONCLUSIONS
Near-normoglycemia remission in obese African American patients with KPDM and ketosis-resistant type 2 diabetes is associated with a remarkable recovery in basal and stimulated insulin secretion. A high FFA level by intralipid infusion for 48 h was not associated with β-cell decompensation (lipotoxicity) in KPDM patients.
Genetic Susceptibility Factors in a Cohort of 38 Patients with SAPHO Syndrome: A Study of PSTPIP2, NOD2, and LPIN2 Genes
Authors: HURTADO-NEDELEC MARGARITA , CHOLLET-MARTIN SYLVIE , CHAPETON DIANA , HUGOT JEAN-PIERRE , HAYEM GILLES , GÉRARD BÉNÉDICTE 
Published: December 2009

Objective. The SAPHO syndrome (synovitis, acne, pustulosis, hyperostosis, and osteitis) is a rare disorder that mainly affects bone and skin. Chronic multifocal osteitis is the main diagnostic feature. Genetic studies of HLA genes have shown no role for these class II antigens, whereas studies of 2 mouse models (cmo and Lupo) point to a role of the PSTPIP2 gene. We analyzed the PSTPIP2 gene in patients with SAPHO syndrome.Methods. In a cohort of 38 patients with SAPHO we analyzed PSTPIP2 and 2 other candidate genes, NOD2/CARD15 (Crohn's disease occurs in about 10% of SAPHO patients), and LPIN2 (clinical similarities of SAPHO with Majeed syndrome).Results. Rare variants of the 3 genes observed in patients with SAPHO were not specific or were not found more frequently compared to controls, suggesting no major pathogenetic role of these genes in the SAPHO syndrome.Conclusion. We found no association between PSTPIP2, NOD2, and LPIN2 variants and the SAPHO syndrome.
Linkage and Association Studies of Joint Morbidity from Rheumatoid Arthritis
Authors: MIN JIN-YOUNG , MIN KYOUNG-BOK , SUNG JOOHON , CHO SUNG-IL 
Published: December 2009

Objective. To investigate the relationship between genetic variations of rheumatoid arthritis (RA) susceptibility in terms of joint morbidity.Methods. We used data from Genetic Analysis Workshop 15. The Illumina linkage panel IV included 5858 single-nucleotide polymorphisms (SNP), with 5744 SNP passing quality control filters. The phenotypic variables analyzed were the level of rheumatoid factor (RF) and score on the Joint Alignment and Motion (JAM) scale. We modified the scale, dividing by RF values relevant to disease severity. Linkage analysis for affected sibling pairs was done using the MERLIN program, and family-based association tests were carried out using PLINK and FBAT software.Results. We found a high peak (LOD = 3.29; NPL Z = 4.07) near the HLA-DRB1 region on chromosome 6. The linkage at 6p24 at rs1410766 [LOD = 2.66; nonparametric linkage (NPL) Z = 3.23] was statistically significant. Two other regions also showed possible linkage peaks: chromosome 7q30 at rs322812 (LOD = 2.47; NPL Z = 3.39) and chromosome 15p34 at rs347117 (LOD = 1.95; NPL Z = 2.80). For the family-based association study, 7 SNP related to clinical RA severity were detected.Conclusion. Genetic variations may lead to an enhanced risk of joint damage and increased levels of RF. Further studies are needed to elucidate the roles of other genes involved in RA and to explore whether the clinical signs of RA are associated with particular genetic variations.
Changes in Waist Circumference and Body Mass Index in Relation to Changes in Serum Uric Acid in Japanese Individuals
Authors: ISHIZAKA NOBUKAZU , ISHIZAKA YUKO , TODA AKIKO , TANI MIZUKI , KOIKE KAZUHIKO , YAMAKADO MINORU , NAGAI RYOZO 
Published: December 2009

Objective. Studies have shown that obesity is associated with an increase in serum uric acid; and few data are available on the relationship between changes in measures of obesity and changes in uric acid concentrations. We investigated the relationship among percentage changes in waist circumference (%dWC), body mass index (%dBMI), and serum uric acid (%dUA).Methods. The data of 3153 individuals [1968 men, 1185 women (536 premenopausal, 649 postmenopausal)] who underwent general health screening over a 2-year period and were not taking antihyperuricemic medication were analyzed.Results. Stepwise multiple regression analysis showed that %dBMI was associated positively with %dUA in postmenopausal women and men, and the association retained statistical significance after adjustment for changes in blood pressure and in renal function. Association between %dBMI and %dUA was not significant in premenopausal women. In men, %dWC was a predicting factor for %dUA, although it did not remain significant when %dBMI was used as a covariate in the statistical model. Multivariate logistic regression analysis showed that the odds ratio of the association between the lowest %dBMI quartile (%dBMI < –1.86) and the lowest %dUA quartile (%dUA < –7.41) was 2.04 (95% CI 1.35–3.07) in postmenopausal women and 1.46 (95% CI 1.14–1.86) in men.Conclusion. Weight loss may represent an effective nonmedical strategy for reducing serum UA levels, especially in postmenopausal women and men.
The Alarmin Cytokine, High Mobility Group Box 1, Is Produced by Viable Cardiomyocytes and Mediates the Lipopolysaccharide-Induced Myocardial Dysfunction via a TLR4/Phosphatidylinositol 3-Kinase γ Pathway
Authors: Xu Hu , Su Zhaoliang , Wu Jun , Yang Min , Penninger Josef M. , Martin Claudio M. , Kvietys Peter R. , Rui Tao 
Published: December 2009

Abstract
High mobility group box 1 (HMGB1) is an alarmin actively secreted by immune cells and passively released by necrotic nonimmune cells. HMGB1 has been implicated in both cardiac contractile dysfunction and the lethality associated with sepsis/endotoxemia. The aim of the current study was to assess whether viable cardiomyocytes could produce HMGB1 and whether HMGB1 can affect myocardial contractility. LPS was used as a model of sepsis/endotoxemia in mice and isolated cardiac myocytes. LPS increased myocardial expression of HMGB1 in vivo (immunohistochemistry) and production and secretion of HMGB1 by viable cardiac myocytes in vitro (Western). LPS increased the phosphorylation status of PI3Kγ in cardiac myocytes, an effect not observed in TLR4−/− myocytes. Genetic (PI3Kγ−/−) or pharmacologic (AS605240) blockade of PI3Kγ ameliorated the LPS-induced 1) cardiomyocyte production and secretion of HMGB1 in vitro and 2) HMGB1 expression in the myocardium in vivo. The LPS-induced depression of myocardial contractility was prevented by the HMGB1 antagonist, A-box. Genetic (PI3Kγ−/−) or pharmacologic (AS605240) blockade of PI3Kγ ameliorated the LPS-induced decrease in myocardial contractility. No evidence of inflammatory infiltrate was noted in any of the in vivo studies. The findings of the current study indicate that 1) LPS can induce HMGB1 secretion by viable cardiac myocytes through a TLR4/PI3Kγ signaling pathway, and 2) HMGB1 plays a role in the LPS-induced myocardial contractile dysfunction. The results of the current study also have broader implications (i.e., that viable parenchymal cells, such as cardiac myocytes, participate in the alarmin response).
Cohomologie $L^p$ et pincement
Authors: Pansu Pierre 
Published: December 2009

A sharp vanishing theorem for the

L^p

cohomology torsion of Riemannian manifolds with pinched negative curvature is given. It follows that certain negatively curved homogeneous spaces cannot be quasiisometric to better pinched manifolds.

Résumé.

On donne un critère optimal d’annulation de la torsion en cohomologie

L^p

pour les variétés riemanniennes à courbure sectionnelle négative pincée. Il en résulte que certains espaces homogènes à courbure négative ne sont pas quasiisométriques à des variétés plus pincées qu’eux.
Smooth divisors of projective hypersurfaces
Authors: Ellia Philippe , Franco Davide , Gruson Laurent 
Published: December 2009

Let

X  ⊂ ℙ^n

be a smooth codimension 2 subvariety. We first prove a “positivity lemma” (Lemma 1.1) which is a direct application of the positivity of

N_X (−1)

. Then we first derive two consequences:

The result in 1) is not effective, but 2) is. Then we obtain precise inequalities connecting the usual numerical invariants of a smooth subcanonical subvariety

X  ⊂ ℙ^n

,

n ≥ 5

(the degree

d

, the integer

e

such that

\omega_X ⋍ \mathcal O_X (e)

, the least degree,

s

, of a hypersurface containing

X

). In particular we prove:

s ≥ n + 1

if

X

is not a complete intersection.
Groups with finitely many conjugacy classes and their automorphisms
Authors: Minasyan Ashot 
Published: December 2009

We combine classical methods of combinatorial group theory with the theory of small cancellation over relatively hyperbolic groups to construct finitely generated torsion-free groups that have only finitely many classes of conjugate elements. Moreover, we present several results concerning embeddings into such groups.
As another application of these techniques, we prove that every countable group C can be realized as a group of outer automorphisms of a group N, where N is a finitely generated group having Kazhdan’s property (T) and containing exactly two conjugacy classes.
CAT(0) and CAT(-1) dimensions of torsion free hyperbolic groups
Authors: Brady Noel , Crisp John 
Published: December 2009

We show that a particular free-by-cyclic group G has CAT(0) dimension equal to 2, but CAT(-1) dimension equal to 3. Starting from a fixed presentation 2-complex we define a family of non-positively curved piecewise Euclidean “model” spaces for G, and show that whenever the group acts properly discontinuously by isometries on any proper 2-dimensional CAT(0) space X there exists a G-equivariant map from the universal cover of one of the model spaces to X which is locally isometric off the 0-skeleton and injective on vertex links.
From this we deduce bounds on the relative translation lengths of various elements of G acting on any such space X by first studying the geometry of the model spaces. By taking HNN-extensions of G we then produce an infinite family of 2-dimensional hyperbolic groups which do not act properly discontinuously by isometries on any proper CAT(0) metric space of dimension 2. This family includes a free-by-cyclic group with free kernel of rank 6.
Rigidity theory for matroids
Authors: Develin Mike , Martin Jeremy L , Reiner Victor 
Published: December 2009

Combinatorial rigidity theory seeks to describe the rigidity or flexibility of bar-joint frameworks in Rd in terms of the structure of the underlying graph G. The goal of this article is to broaden the foundations of combinatorial rigidity theory by replacing G with an arbitrary representable matroid M. The ideas of rigidity independence and parallel independence, as well as Laman's and Recski's combinatorial characterizations of 2-dimensional rigidity for graphs, can naturally be extended to this wider setting. As we explain, many of these fundamental concepts really depend only on the matroid associated with G (or its Tutte polynomial), and have little to do with the special nature of graphic matroids or the field R.
Our main result is a “nesting theorem” relating the various kinds of independence. Immediate corollaries include generalizations of Laman's Theorem, as well as the equality of 2-rigidity and 2-parallel independence. A key tool in our study is the space of photos of M, a natural algebraic variety whose irreducibility is closely related to the notions of rigidity independence and parallel independence.
The number of points on this variety, when working over a finite field, turns out to be an interesting Tutte polynomial evaluation.
Pincement spectral en courbure de Ricci positive
Authors: Bertrand Jérôme 
Published: December 2009

We show that for

n

-dimensional manifolds with

\mathrm{Ric} ≥ (n − 1)g

and for

k

in

\{1,\ldots ,n + 1\}

, the

k

-th eigenvalue for the Laplacian is close to

n

if and only if the manifold contains a subset which is Gromov–Hausdorff close to the sphere

\mathbb S^{k −1}

. For

k = n + 1

, this gives a new proof of results of Colding and Petersen which show that the

(n + 1)

-th eigenvalue is close to

n

if and only if the manifold is Gromov–Hausdorff close to the

n

-sphere.

Résumé

Dans cet article, nous démontrons que sur les variétés riemanniennes de dimension

n

vérifiant

\mathrm{Ric} ≥ (n − 1)g

et pour

k

dans

\{1,\ldots ,n + 1\}

, la ke valeur propre du laplacien est proche de

n

si et seulement si la variété contient une partie Gromov–Hausdorff proche de la sphère

\mathbb S^{k −1}

. Pour

k = n + 1

, nous obtenons une nouvelle preuve des résultats de Petersen et Colding qui montrent que pour de telles variétés, la

(n + 1)^{\text{e}}

valeur propre est proche de

n

si et seulement si la variété est Gromov–Hausdorff proche de la sphère de dimension

n

.