bluuebunny/crossref_metadata_2025 huggingface dataset:
3D finite-difference frequency-domain modeling of visco-acoustic wave propagation using a massively parallel direct solver: A feasibility study
Authors: Operto Stéphane , Virieux Jean , Amestoy Patrick , L’Excellent Jean-Yves , Giraud Luc , Ali Hafedh Ben Hadj
Published: September 2007

We present a finite-difference frequency-domain method for 3D visco-acoustic wave propagation modeling. In the frequency domain, the underlying numerical problem is the resolution of a large sparse system of linear equations whose right-hand side term is the source. This system is solved with a massively parallel direct solver. We first present an optimal 3D finite-difference stencil for frequency-domain modeling. The method is based on a parsimonious staggered-grid method. Differential operators are discretized with second-order accurate staggered-grid stencils on different rotated coordinate systems to mitigate numerical anisotropy. An antilumped mass strategy is implemented to minimize numerical dispersion. The stencil incorporates 27 grid points and spans two grid intervals. Dispersion analysis showsthat four grid points per wavelength provide accurate simulations in the 3D domain. To assess the feasibility of the method for frequency-domain full-waveform inversion, we computed simulations in the 3D SEG/EAGE overthrust model for frequencies 5, 7, and [Formula: see text]. Results confirm the huge memory requirement of the factorization (several hundred Figabytes) but also the CPU efficiency of the resolution phase (few seconds per shot). Heuristic scalability analysis suggests that the memory complexity of the factorization is [Formula: see text] for a [Formula: see text] grid. Our method may provide a suitable tool to perform frequency-domain full-waveform inversion using a large distributed-memory platform. Further investigation is still necessary to assess more quantitatively the respective merits and drawbacks of time- and frequency-domain modeling of wave propagation to perform 3D full-waveform inversion.
3D finite-difference dynamic-rupture modeling along nonplanar faults
Authors: Cruz-Atienza Víctor M. , Virieux Jean , Aochi Hideo
Published: September 2007

Proper understanding of seismic emissions associated with the growth of complexly shaped microearthquake networks and larger-scale nonplanar fault ruptures, both in arbitrarily heterogeneous media, requires accurate modeling of the underlying dynamic processes. We present a new 3D dynamic-rupture, finite-difference model called the finite-difference, fault-element (FDFE) method; it simulates the dynamic rupture of nonplanar faults subjected to regional loads in complex media. FDFE is based on a 3D methodology for applying dynamic-rupture boundary conditions along the fault surface. The fault is discretized by a set of parallelepiped fault elements in which specific boundary conditions are applied. These conditions are applied to the stress tensor, once transformed into a local fault referenceframe. Numerically determined weight functions multiplying particle velocities around each element allow accurate estimates of fault kinematic parameters (i.e., slip and slip rate) independent of faulting mechanism. Assuming a Coulomb-like slip-weakening friction law, a parametric study suggests that the FDFE method converges toward a unique solution, provided that the cohesive zone behind the rupture front is well resolved (i.e., four or more elements inside this zone). Solutions are free of relevant numerical artifacts for grid sizes smaller than approximately [Formula: see text]. Results yielded by the FDFE approach are in good quantitative agreement with those obtained by a semianalytical boundary integral method along planar and nonplanar parabola-shaped faults. The FDFE method thus provides quantitative, accurate results for spontaneous-rupture simulations on intricate fault geometries.
Antipituitary Antibodies in Idiopathic Hyperprolactinemic Patients
Authors: DE BELLIS ANNAMARIA , COLAO ANNAMARIA , PIVONELLO ROSARIO , SAVOIA ANTONELLA , BATTAGLIA MARINA , RUOCCO GIUSEPPE , TIRELLI GILDA , LOMBARDI GAETANO , BELLASTELLA ANTONIO , BIZZARRO ANTONIO
Published: September 2007

Abstract:  Hyperprolactinemia is often observed in lymphocytic hypophysitis (LYH). To clarify the possible autoimmune pituitary involvement in patients with apparently idiopathic hyperprolactinemia we investigated the presence of antipituitary antibodies (APA) in hyperprolactinemic patients with idiopathic hyperprolactinemia and in those with prolactinoma. Sixty‐six hyperprolactinemic patients (52 F, 14 M age range 28–42 years, group1) were studied. Of them, 34 out of 66 showed clinical features of hyperprolactinemia and subsequently underwent cabergoline therapy; the 32 out of 66 patients without symptoms of hyperprolactinemia did not receive cabergoline therapy. Moreover, 32 patients (24 F/8M, age range 23–44 years) with hyperprolactinemia due to microprolactinoma (group 2) were also studied. APA, by immunofluorescence method, and anterior pituitary function were evaluated in both groups of patients. APA were present in 17 out of 66 (25.7%) patients in group 1 with titers ranging from 1/16 to 1/64. All patients of group 2 were considered APA negative because these antibodies were found at low titer (≤1:4) only in five of them. With regard to the function of other pituitary hormones, all APA‐negative patients in group 1 and in group 2 showed a normal pituitary function; instead, a partial anterior pituitary impairment was observed in 6 out of 17 (35.3%) APA‐positive patients. In asymptomatic patients with apparently idiopathic hyperprolactinemia, APA detection could be useful to disclose forms of potential/subclinical stage of LYH. A future longitudinal study of these patients submitted to cabergoline therapy or free of therapy may be helpful to clarify this assumption.
Altered Pattern of Connectivity in Chagas Disease
Authors: PAVÓN‐MARTÍNEZ NATALIA , MASSO‐ROJAS FELIPE , LÓPEZ‐ALCÁNTARA RUTH , MONTEÓN VICTOR MANUEL
Published: September 2007

Abstract:  It has been proposed that natural autoreactivity plays a physiological role in the immune system by connecting all these clones (Id/anti‐Id) and forming a dense and highly regulated network. In the present work, we analyzed the connectivity pattern in Chagas disease. Serum samples of 20 chronic chagasic cardiopathy (CCC) patients with dilated cardiopathy, 20 infected–asymptomatic subjects (IAS), and 20 healthy seronegative controls (H) were tested. Pattern of connectivity was distinguishable from that of healthy donor and those with CCC and IAS. This suggests that there are alterations in regulatory networks, inclusive being more evident in CCC patients than in IAS.
Are Neurotrophins Important in Ulcerative Colitis?
Authors: JOHANSSON MALIN , NORRGÅRD ÖRJAN , FORSGREN STURE
Published: September 2007

Abstract:  Neurotrophins are known to have growth, survival‐promoting, and healing effects. The importance of neurotrophins in ulcerative colitis (UC) is, however, unclear. Recent studies in our group revealed that an occurrence of marked changes in neurotrophin expression patterns was related to a worsening of the disease process. There was thus an upregulation for the lamina propria cells but a downregulation in nerve structures concerning neurotrophin expressions in severe UC. The observations show that changes in the neurotrophin system are a part of the disease process in UC and are of interest as treatments interfering with neurotrophin effects in other situations have been found to have trophic and healing effects.
Role of the HLA Class II
Authors: DE RE VALLI , CAGGIARI LAURA , SIMULA MARIA PAOLA , DE VITA SALVATORE , MAZZARO CESARE , LENZI MARCO , MASSIMO GALLI M. , MONTI GIUSEPPE , FERRI CLODOVEO , ZIGNEGO ANNA LINDA , GABRIELLI ARMANDO , SANSONNO DOMENICO , DAMMACCO FRANCO , LIBRA MASSIMO , SACCHI NICOLETTA , TALAMINI RENATO , SPINA MICHELE , TIRELLI UMBERTO , CANNIZZARO RENATO , DOLCETTI RICCARDO
Published: September 2007

Abstract:  The paper highlights the role of different HLA class II molecules in hepatic and lymphoproliferative HCV‐related disorders. HLA molecules have been reviewed, according to an in silico cluster classification, based on the sequence, the biochemical structure of the pockets, and the functional characteristics of the HLA II molecules. Thus, by reducing the complexity of HLA II polymorphism, charateristics that unite different HLA molecules with specific HCV‐associated pathologies may be recognized with greater case. Results show that HLA clusters associated with better dlimination of the virus are protective against HCC development, while the same clusters are associated with a higher risk of developing cryoglobulinemic syndrome and the concomitant NHL. These data added further acknowledgements on pathogenetic mechanisms associated with HCV infection. Results also highlight differences of NHL occurring in HCV‐positive subjects, with or without a concomitant type II autoimmune cryoglobulinemic syndrome, suggesting that cryoglobulinemic background associated with NHL should be considered in the evaluation of the effectiveness of new therapies in the course of HCV‐associated NHLs.
Humoral and Cellular Monitoring to Predict the Development of Infection in Crohn's Disease Patients Beginning Treatment with Infliximab
Authors: CARBONE J. , GONZALEZ‐LARA V. , SARMIENTO E. , CHEAN C. , PEREZ J. L. , MARIN I. , RODRÍGUEZ‐MOLINA J. J. , GIL J. , FERNÁNDEZ‐CRUZ E.
Published: September 2007

Abstract:  Although severe infectious complications are rare, it is important to properly screen patients for predisposing conditions before beginning treatment with infliximab. We assessed immunity markers that might provide prognostic value for the development of infection in Crohn's disease patients after treatment with infliximab. In a prospective study, 34 fistulizing Crohn's disease patients (mean age 37 years) were studied. Patients were scheduled to receive three infusions of infliximab (5 mg/kg) at weeks 0, 2, and 6. Immunologic studies: Serum immunoglobulin (IgG, IgA, IgM), IgG‐subclasses, and complement (C3, C4, factor B) determined by nephelometry; CD3+, CD3+CD4+, CD3+CD8+, CD19+, and CD56+CD3– lymphocyte subsets performed by flow cytometry. During a mean follow‐up of 56 months, 1 patient had disseminated tuberculosis and 2 patients had severe bacterial infections. The presence of infection was associated with significantly higher IgM (246 vs. 121 mg/dL; Mann‐Whitney test, P= 0.01), lower C3 (64 vs. 118, P= 0.02), lower C4 concentrations (12 vs. 25, P= 0.02), and with decreased levels of CD19 B cells (47 vs. 290, P= 0.03) in the baseline study. Further prospective studies in a larger number of patients are suggested to examine whether early monitoring of immunocompetence might help to identify the risk of infection in patients treated with infliximab.
Serum Eosinophil Cationic Protein
Authors: GUILPAIN PHILIPPE , AUCLAIR JEAN‐FRANÇOIS , TAMBY MATHIEU C. , SERVETTAZ AMÉLIE , MAHR ALFRED , WEILL BERNARD , GUILLEVIN LOÏC , MOUTHON LUC
Published: September 2007

Abstract:  The cytotoxic proteins released by activated eosinophils should play a role in the development of Churg‐Strauss syndrome (CSS). Eighteen patients (15 males and 3 females, age 41 ± 13.3 years) with CSS according to the American College of Rheumatology criteria were included in the study. Thirteen serum samples from 11 patients were obtained at the time of disease flare, and the sera from 6 of them were also obtained at the time of clinical remission. Sera from seven other patients were obtained in clinical remission. Anti‐neutrophil cytoplasm antibodies were detected in four (22.2%) patients. Fifteen healthy individuals were used as controls. Mean eosinophil count differed significantly between CSS patients with active disease and patients in clinical remission (3,407/mm3 vs. 258/mm3; P < 0.01), between CSS patients with active disease and healthy individuals (3,407/mm3 vs. 211/mm3; P < 0.01). Mean serum ECP levels differed significantly between patients with active or inactive disease (219 μg/L vs. 56.8 μg/L; P < 0.0001), between patients with active disease and healthy individuals (219 μg/L vs. 26.2 μg/L; P < 0.0001), but not between patients with inactive disease and healthy individuals (ns). Peripheral blood eosinophils count correlated with serum ECP during CSS flares disease (R= 0.6264; P < 0.05) and during periods of remission (R= 0.4798; P < 0.05). Our results support that ECP might be used as a disease activity marker in CSS.
Spectrum of Wegener Granulomatosis in a Mexican Population
Authors: FLORES‐SUÁREZ LUIS FELIPE , VILLA ANTONIO R.
Published: September 2007

Abstract:  Wegener granulomatosis (WG) is a disease considered infrequent among non‐Caucasians. Few data exist on its characteristics in Latin America, except for isolated case reports and a paper on clinical features from a Chilean group. In this article we present the clinical characteristics of our cohort plus a preliminary evaluation of the risk factors for death. In comparison to large series from countries with a high WG prevalence, we observed similar age and gender distribution, disease category (localized or generalized), PR3‐ANCA positivity, remission, relapse frequency, mortality, and death causes. These last ones are equally distributed, but infections account for an important proportion. Factors related with mortality were mainly those associated with side effects of treatment. We are currently expanding the data on this item as in other series, death is mainly related to the disease itself. The pending agenda includes knowing the prevalence and incidence of WG in Mexico, as well as other characteristics, such as genetic factors, that may influence its behavior in our country.
Role of Trypanosoma cruzi Autoreactive T Cells in the Generation of Cardiac Pathology
Authors: GIRONÈS NÚRIA , CARRASCO‐MARIN EUGENIO , CUERVO HENAR , GUERRERO NÉSTOR ADRIÁN , SANOJA CRISTINA , JOHN SPARROW , FLORES‐HERRÁEZ REYES , FERNÁNDEZ‐PRIETO LORENA , CHICO‐CALERO ISABEL , SALGADO HUGO , CARRIÓN JAVIER , FRESNO MANUEL
Published: September 2007

Abstract:  Chagas disease, caused by Trypanosoma cruzi, affects several million people in Central and South America. About 30% of chronic patients develop cardiomyopathy probably caused by parasite persistence and/or autoimmunity. While several cross‐reactive antibodies generated during mammal T. cruzi infection have been described, very few cross‐reactive T cells have been identified. We performed adoptive transfer experiments of T cells isolated from chronically infected mice. The results showed the generation of cardiac pathology in the absence of parasites. We also transferred cross‐reactive SAPA‐specific T cells and observed unspecific alterations in heart repolarization, cardiac inflammatory infiltration, and tissue damage.
Circulating Tissue Factor Procoagulant Activity and Thrombin Generation in Patients with Type 2 Diabetes: Effects of Insulin and Glucose
Authors: Boden Guenther , Vaidyula Vijender R. , Homko Carol , Cheung Peter , Rao A. Koneti
Published: September 2007

Context: Type 2 diabetes mellitus (T2DM) is a hypercoagulable state. Tissue factor (TF) is the principal initiator of blood coagulation.

Objective: Our objective was to examine the effects of hyperglycemia and hyperinsulinemia on the TF pathway of blood coagulation in T2DM.

Design: Three study protocols were used: 1) acute correction of hyperglycemia (with iv insulin) followed by 24 h of euglycemia, 2) 24 h of selective hyperinsulinemia, and 3) 24 h of combined hyperinsulinemia and hyperglycemia.

Setting: The study took place at a clinical research center.

Study Participants: Participants included 18 T2DM patients and 22 nondiabetic controls.

Results: Basal TF-procoagulant activity (TF-PCA), monocyte TF mRNA, plasma coagulation factor VII (FVIIc), and thrombin-anti-thrombin complexes were higher in T2DM than in nondiabetic controls, indicating a chronic procoagulant state. Acutely normalizing hyperglycemia over 2–4 h resulted in a small (∼7%) but significant decline in TF-PCA with no further decline over 24 h. Raising insulin levels alone raised TF-PCA by 30%, whereas raising insulin and glucose levels together increased TF-PCA (by 80%), thrombin-anti-thrombin complexes, and prothrombin fragment 1.2. Plasma FVIIa and FVIIc declined with increases in TF-PCA.

Conclusion: We conclude that the combination of hyperglycemia and hyperinsulinemia, common in poorly controlled patients with T2DM, contributes to a procoagulant state that may predispose these patients to acute cardiovascular events.
Semiautomated improvement of RNA alignments
Authors: Andersen Ebbe S. , Lind-Thomsen Allan , Knudsen Bjarne , Kristensen Susie E. , Havgaard Jakob H. , Torarinsson Elfar , Larsen Niels , Zwieb Christian , Sestoft Peter , Kjems Jørgen , Gorodkin Jan
Published: September 2007

We have developed a semiautomated RNA sequence editor (SARSE) that integrates tools for analyzing RNA alignments. The editor highlights different properties of the alignment by color, and its integrated analysis tools prevent the introduction of errors when doing alignment editing. SARSE readily connects to external tools to provide a flexible semiautomatic editing environment. A new method, Pcluster, is introduced for dividing the sequences of an RNA alignment into subgroups with secondary structure differences. Pcluster was used to evaluate 574 seed alignments obtained from the Rfam database and we identified 71 alignments with significant prediction of inconsistent base pairs and 102 alignments with significant prediction of novel base pairs. Four RNA families were used to illustrate how SARSE can be used to manually or automatically correct the inconsistent base pairs detected by Pcluster: the mir-399 RNA, vertebrate telomase RNA (vert-TR), bacterial transfer-messenger RNA (tmRNA), and the signal recognition particle (SRP) RNA. The general use of the method is illustrated by the ability to accommodate pseudoknots and handle even large and divergent RNA families. The open architecture of the SARSE editor makes it a flexible tool to improve all RNA alignments with relatively little human intervention. Online documentation and software are available at http://sarse.ku.dk.
Yeast Rrp14p is a nucleolar protein involved in both ribosome biogenesis and cell polarity
Authors: Yamada Hiroko , Horigome Chihiro , Okada Takafumi , Shirai Chiharu , Mizuta Keiko
Published: September 2007

We previously cloned RRP14/YKL082c, whose product exhibits two-hybrid interaction with Ebp2p, a regulatory factor of assembly of 60S ribosomal subunits. Depletion of Rrp14p results in shortage of 60S ribosomal subunits and retardation of processing from 27S pre-rRNA to 25S rRNA. Furthermore, 35S pre-rRNA synthesis appears to decline in Rrp14p-depleted cells. Rrp14p interacts with regulatory factors of 60S subunit assembly and also with Utp11p and Faf1p, which are regulatory factors required for assembly of 40S ribosomal subunits. We propose that Rrp14p is involved in ribosome synthesis from the beginning of 35S pre-rRNA synthesis to assembly of the 60S ribosomal subunit. Disruption of RRP14 causes an extremely slow growth rate of the cell, a severe defect in ribosome synthesis, and a depolarized localization of cortical actin patches throughout the cell cycle. These results suggest that Rrp14p has dual functions in ribosome synthesis and polarized cell growth.
First experimental evidence for the preferential stabilization of the natural D- over the nonnatural L-configuration in nucleic acids
Authors: Bolik Sarah , Rübhausen Michael , Binder Stephan , Schulz Benjamin , Perbandt Markus , Genov Nicolay , Erdmann Volker , Klussmann Sven , Betzel Christian
Published: September 2007

The homochirality of biomolecules is a prerequisite for the origin and evolution of terrestrial life. The unique selection of D-monosaccharides, in particular, D-ribose in RNA and D-deoxyribose in DNA, leads to the construction of proteins by L-amino acids. This points to the exclusive role of stereoselectivity in the most important physiological processes. So far, there is no experimental confirmation for the theoretical calculations of the energy differences between enantiomers used for the explanation of the stereoselection of biomolecules. Therefore, the question of why nature prefers one configuration over the other still lacks a definitive answer. Here, we present the first experimental evidence that the D-enantiomer of RNA has a different electronic structure compared to the corresponding L-enantiomer. When varying the incident photon energy of the ultraviolet Raman probe across 5 eV, D- and L-isomers of the RNA duplex with the sequence [r(CUGGGCGG).r(CCGCCUGG)] show differences in the intensity of the vibrational modes with energies of 124.0 meV to 210.8 meV. The intensity difference of these vibrational modes can be traced back to energy differences in the electronic levels of D- and L-RNA leading to the preferential stabilization of the naturally occurring D-configuration of RNA over the L-configuration.
New Precedence Theorems for One-Machine Weighted Tardiness
Authors: Kanet J. J.
Published: September 2007

In an earlier paper by Emmons [Emmons, H. 1969. One-machine sequencing to minimize certain functions of job tardiness. Oper. Res. 17 701–715], the problem of sequencing jobs on a single machine in order to minimize total tardiness was analyzed. Emmons provided three theorems for specifying precedence relations for pairs of jobs. His theorems apply when the tardiness penalty for each job grows at the same rate. Rinnooy Kan et al. [Rinnooy Kan, A. H. G., B. J. Lageweg, J. K. Lenstra. 1975. Minimizing total costs in one-machine scheduling. Oper. Res. 23 908–927] later extended Emmons’s theorems to the case when job tardiness penalties can grow at different rates for different jobs. Provided here is a set of theorems, stronger than those of Rinnooy Kan et al., that more fully exploits the special properties of the weighted tardiness function, allowing for greater reduction of the solution space.
Algorithms for Single-Item Lot-Sizing Problems with Constant Batch Size
Authors: Van Vyve Mathieu
Published: September 2007

The main result of this paper is an O(n3) algorithm for the single-item lot-sizing problem with constant batch size and backlogging. We consider a general number of installable batches, i.e., in each time period t we may produce up to mt batches, where the mt are given and time-dependent. This generalizes earlier results as we consider backlogging and a general number of maximum batches. We also give faster algorithms for three special cases of this general problem. When backlogging is not allowed and the costs satisfy the Wagner-Whitin property, the problem is solvable in O(n2 log n) time. When the production in each period is required to be either zero or equal to the installed capacity, it is possible to solve the problem with and without backlogging in O(n2) and O(n log n) time, respectively.
Quasi-Product Forms for Lévy-Driven Fluid Networks
Authors: Dębicki K. , Dieker A. B. , Rolski T.
Published: September 2007

We study stochastic tree fluid networks driven by a multidimensional Lévy process. We are interested in (the joint distribution of) the steady-state content in each of the buffers, the busy periods, and the idle periods. To investigate these fluid networks, we relate the above three quantities to fluctuations of the input Lévy process by solving a multidimensional Skorokhod reflection problem. This leads to the analysis of the distribution of the componentwise maximums, the corresponding epochs at which they are attained, and the beginning of the first last-passage excursion. Using the notion of splitting times, we are able to find their Laplace transforms. It turns out that, if the components of the Lévy process are “ordered,” the Laplace transform has a so-called quasi-product form.

The theory is illustrated by working out special cases, such as tandem networks and priority queues.
Partially B-Regular Optimization and Equilibrium Problems
Authors: Pang J. S.
Published: September 2007

This paper introduces a concept termed partial B-regularity for a feasible solution to a bivariate constraint system and shows that this condition leads to the equivalence between the B-stationarity of a pair of lifted and unlifted programs. In particular, for an optimization problem with a univariate pseudoconvex objective function constrained by such a nonconvex bivariate system, partial B-regularity provides a sufficient condition for a B-stationary point to be globally optimal. Applications of partial B-regularity to several classes of optimization and equilibrium problems are presented; these include a lexicographic optimization problem, a nonconvex mathematical program with equilibrium constraints (MPEC) that arises from a convex implicit value-function optimization problem, and a Nash equilibrium program with equilibrium constraints.
Characterization and Clinical Management of Clozapine-Induced Fever
Authors: Lowe Carolina Molina , Grube Rebekah R Arthur , Scates Ann C
Published: September 2007

Objective:

To characterize clozapine-induced fever and suggest clinically relevant management recommendations.

Data Sources:

Literature was accessed through MEDLINE (1966–June 2007) using the terms clozapine, fever, and adverse effects. In addition, reference citations from publications identified were reviewed.

Study Selection and Data Extraction:

All English-language articles about human studies ot fever associated with the use of clozapine were evaluated.

Data Synthesis:

Mild to high-grade fever frequently accompanies clozapine therapy. Fever usually occurs within 10–15 days after treatment initiation and has been reported to last between 2 and 4 days. The mechanism and clinical implications of clozapine-induced fever are unclear. The primary concern for clinicians, with regard to these fevers, is the possibility of 2 serious conditions: agranulocytosis with infection or neuroleptic malignant syndrome (NMS). However, the presence of fever during clozapine therapy does not appear to predict agranulocytosis, NMS, or an increased rate of drug discontinuation at 1 year.

Conclusions:

Available data suggest that clozapine-induced fevers are benign: once infectious and other medical causes for fever are ruled out, clozapine therapy can be continued.
Feckless fathers and monopolizing mothers: Motive, identity, and fundamental truths in the Australian Public Inquiry into Child Custody
Authors: Fogarty Kathryn , Augoustinos Martha
Published: September 2007

This paper presents findings from a discursive analysis of Hansard recordings of the public hearings of the Australian Public Inquiry into Child Custody. Using a synthesis of membership categorization analysis, sequential conversation analysis, and rhetorical analysis, the study shows how two witnesses, and the committee members they interacted with, oriented to a normative requirement to talk in terms of being motivated by children's interests. Building on discursive psychological research into ways that categories‐in‐talk can imply and infer things about psychological concepts such as motive and identity, this paper shows how motive and identity were a salient participants' concern in a setting where an important social issue was being contested. A contribution is the illumination of several common ideas that formed part of people's sense making about parenting practices and what children purportedly need. Some implications of an uncritical acceptance of these ideas by psychologists, researchers, and people influential in assisting families with post‐separation parenting arrangements are suggested.
An Oedometer-Type Pressure Plate SWCC Apparatus
Authors: Perez-Garcia Natalia , Houston Sandra L. , Houston William N. , Padilla J. Manuel
Published: September 2007

A new oedometer device for SWCC determination has been evaluated by testing a wide range of soil types, and recommendations for best practices for use of this device have been made. The new device allows application and control of the net normal stress, σ−ua, in addition to the matric suction, ua−uw. Thus it can be used to simulate a range of overburden stresses and various other stress states of interest. It also allows the measurement of specimen volume change and the use of a single specimen for determination of the SWCC. The evaluation includes issues of temperature control, air diffusion through high air entry ceramic disks, and study of potential sources of error in water content determination for the SWCC. It is concluded that the new oedometer device can be used to obtain an accurate SWCC for a single specimen up to 1500kPa. General recommendations for appropriate use of the equipment and corrections to SWCC data obtained using axis translation pressure plate-type devices are made.
Synergistic Tribological Performances of Borate Additive in Lubricants
Authors: Hu Jian-Qiang , Hu Yi-Qin , Liu Guang-Long , Ma Yu-Hong
Published: September 2007

A four-ball tester was used to evaluate the tribological behaviors of nitrogen-containing borate (BNO) combined with zinc dialkyldithiophosphate (ZDDP) and tin dialkyldithiocarbamates (SnDDC) in liquid paraffin or mineral oil, even respectively. The surface analytical tools such as X-ray photoelectron spectrometer (XPS), X-ray diffractometer (XRD), and energy dispersive X-ray (EDX) were used to investigate the chemical states of some typical elements and composition on the rubbing surface of the wear scar. The tribological results show that BNO exhibits better antiwear properties in base oils, and can exhibit good antiwear synergism when it was combined with additives ZDDP and SnDDC, respectively, while the antiwear properties of oil-containing additive packages are optimal under certain concentration ranges. The results of XPS and XRD analyses indicated that BNO can form tribochemical mixed protective films consisting of BN or B2O3 compounds on the rubbing surface, and the combination of BNO with SnDDC may form tin, oxides, sulfide, and N-containing compounds on the rubbing surfaces, which contribute to improving the tribological properties of lubricants. A considerable amount of ZDDP can be partially replaced by BNO in synergistic mixtures, or replaced completely by the combination of BNO with SnDDC, which is especially important for ZDDP used in ecologically sensitive applications.
Semaphorin3D Regulates Axon–Axon Interactions by Modulating Levels of L1 Cell Adhesion Molecule
Authors: Wolman Marc A. , Regnery Ann M. , Becker Thomas , Becker Catherina G. , Halloran Mary C.
Published: September 2007

The decision of a growing axon to selectively fasciculate with and defasciculate from other axons is critical for axon pathfinding and target innervation. Fasciculation can be regulated by cell adhesion molecules that modulate interaxonal adhesion and repulsive molecules, expressed by surrounding tissues that channel axons together. Here we describe crosstalk between molecules that mediate these mechanisms. We show that Semaphorin3D (Sema3D), a classic repulsive molecule, promotes fasciculation by regulating L1 CAM levels and axon–axon interactions rather than by creating a repulsive surround. Knockdown experiments show that Sema3D and L1 genetically interact to promote fasciculation. Sema3D overexpression increases and Sema3D knockdown decreases levels of axonal L1 protein. Moreover, excess L1 rescues defasciculation caused by the loss of Sema3D.In vivotime-lapse imaging reveals that Sema3D or L1 knockdown cause identical defects in growth cone behaviors during axon–axon interactions, consistent with a loss of adhesion. These results reveal a novel mechanism by which a semaphorin promotes fasciculation and modulates axon–axon interactions by regulating an adhesion molecule.
Spike-Timing-Dependent Plasticity of Neocortical Excitatory Synapses on Inhibitory Interneurons Depends on Target Cell Type
Authors: Lu Jiang-teng , Li Cheng-yu , Zhao Jian-Ping , Poo Mu-ming , Zhang Xiao-hui
Published: September 2007

Repetitive correlated spiking can induce long-term potentiation (LTP) and long-term depression (LTD) of many excitatory synapses on glutamatergic neurons, in a manner that depends on the timing of presynaptic and postsynaptic spiking. However, it is mostly unknown whether and how such spike-timing-dependent plasticity (STDP) operates at neocortical excitatory synapses on inhibitory interneurons, which have diverse physiological and morphological characteristics. In this study, we found that these synapses exhibit target-cell-dependent STDP. In layer 2/3 of the somatosensory cortex, the pyramidal cell (PC) forms divergent synapses on fast spiking (FS) and low-threshold spiking (LTS) interneurons that exhibit short-term synaptic depression and facilitation in response to high-frequency stimulation, respectively. At PC-LTS synapses, repetitive correlated spiking induced LTP or LTD, depending on the timing of presynaptic and postsynaptic spiking. However, regardless of the timing and frequency of spiking, correlated activity induced only LTD at PC-FS synapses. This target-cell-specific STDP was not caused by the difference in the short-term plasticity between these two types of synapses. Activation of postsynaptic NMDA subtype of glutamate receptors (NMDARs) was required for LTP induction at PC-LTS synapses, whereas activation of metabotropic glutamate receptors was required for LTD induction at both PC-LTS and PC-FS synapses. Additional analysis of synaptic currents suggests that LTP and LTD of PC-LTS synapses, but not LTD of PC-FS synapses, involves presynaptic modifications. Such dependence of both the induction and expression of STDP on the type of postsynaptic interneurons may contribute to differential processing and storage of information in cortical local circuits.
Free Synthetic and Natural Estrogen Hormones in Influent and Effluent of Three Municipal Wastewater Treatment Plants
Authors: Chimchirian Robert F. , Suri Rominder P.S. , Fu Hongxiang
Published: September 2007

Three municipal wastewater treatment plants (WWTPs) in southeastern Pennsylvania were sampled to determine the presence and concentrations of 12 natural and synthetic estrogen hormones in the wastewater influent and effluent. The target estrogens were 17α‐estradiol, estrone, estriol, equilin, 17α‐dihydroequilin, 17β‐estradiol, 17α‐ethinyl estradiol, gestodene, norgestrel, levonorgestrel, medrogestone, and trimegestone. One WWTP uses a biofilm reactor (packed‐bed trickling filter), and the other two use suspended‐growth media (continuously stirred activated sludge reactor and sequential batch reactor). Estrone was detected in all the three plants; estriol and estradiol were detected at two WWTPs; and 17 α‐dihydroequilin and 17 α‐ethinyl estradiol were detected at one WWTP. The concentration of estrogens in the influent and effluent of the three treatment plants ranged from 1.2 to 259 ng/L and 0.5 to 49 ng/L, respectively. The percentage removal of estrogens from the aqueous phase ranged from 41 to 99%, except in the case of 17α‐dihydroequilin; the removal of 17α‐dihydroequilin was negligible. The suspended‐growth media systems showed higher removal efficiencies for estrogens than the biofilm system. The analytical method uses a Varian C‐18 solid‐phase extraction (Varian Inc., Palo Alto, California), followed by a derivatization with bis(trimethylsilyl)trifluoroacetamide. The detection limits for the estrogen compounds ranged from 0.1 to 10 ng/L using a sample size of 1 L. The method recoveries ranged from 71 to 120%, and the relative standard deviation ranged from 6 to 14% for all the hormones.
Operating Parameters for High Nitrite Accumulation during Nitrification in a Rotating Biological Nitrifying Contactor
Authors: Antileo Christian , Roeckel Marlene , Lindemann Jörg , Wiesmann Udo
Published: September 2007

Incomplete nitrification was studied in a completely and partially submerged rotating biological contactor (RBC). In a partially submerged RBC without additional aeration, 50 to 90% nitrite accumulation (α) was achieved at rotation speeds (ω) of 2 to 18 min−1. In a completely submerged RBC operating during 80 days, a higher α of 96% was achieved at ω = 2 min−1. Incomplete nitrification in a completely submerged RBC at oxygen concentrations of 1.5 to 6.8 mg O2/L indicated that the mass transfer of oxygen is rate‐limiting. Modeling of the completely submerged RBC predicts that the oxygen profile will not penetrate the biofilm more than 30 μm, thereby strongly limiting the nitrite‐oxidizer growth and causing high nitrite accumulation. Molecular analysis (i.e., fluorescence in situ hybridization) indicated that the nitrite‐oxidizers are superficially located (<200 μm) and that the ammonia‐oxidizers comprise up to approximately 800 μm of the biofilm.
Biosorption Characteristics of Copper (II), Chromium (III), Nickel (II), and Lead (II) from Aqueous Solutions by Chara sp. and Cladophora sp
Authors: Elmaci Ayşe , Yonar Taner , Özengin Nihan
Published: September 2007

The aim of this research was to expose individual removals of copper, chromium, nickel, and lead from aqueous solutions via biosorption using nonliving algae species, Chara sp. and Cladophora sp. Optimum pH values for biosorption of copper (II), chromium (III), nickel (II), and lead (II) from aqueous solutions were determined to be 6, 7, 7, and 3 for Cladophora sp. and 5, 3, 5, and 4 for Chara sp. respectively. Maximum adsorption capacities of Chara sp. [10.54 for chromium (III) and 61.72 for lead (II)] and Cladophora sp. [6.59 for chromium (III) and 16.75 and 23.25 for lead (II)] for chromium (III) and lead (II) are similar. On the other hand, copper (II) and nickel (II) biosorption capacity of Cladophora sp. [14.28 for copper (II) and 16.75 for nickel (II)] is greater than Chara sp. [6.506 for copper (II) and 11.76 for nickel (II)]. Significantly high correlation coefficients indicated for the Langmuir adsorption isotherm models can be used to describe the equilibrium behavior of copper, chromium, nickel, and lead adsorption onto Cladophora sp. and Chara sp.
Characteristics of Electrolysis, Ozonation, and their Combination Process on Treatment of Municipal Wastewater
Authors: Kishimoto Naoyuki , Morita Yukako , Tsuno Hiroshi , Yasuda Yuuji
Published: September 2007

The characteristics of municipal wastewater treatment by electrolysis, ozonation, and combination processes of electrolysis and aeration using three gaseous species (nitrogen [N2], oxygen [O2], and ozone [O3]) were discussed in this research using ruthenium oxide (RuO2)‐coated titanium anodes and stainless‐steel (SUS304) cathodes. Electrolysis and electrolysis with nitrogen aeration were characterized by a rapid decrease in 5‐day biochemical oxygen demand (BOD5) and total nitrogen and a slow decrease in chemical oxygen demand (COD). In contrast, ozonation, electrolysis with oxygen aeration, and electrolysis with ozone aeration were characterized by transformation of persistent organic matter to biodegradable matter and preservation of total nitrogen. The best energy efficiency in removing BOD5 and total nitrogen was demonstrated by electrolysis, as a result of direct anodic oxidation and indirect oxidation with free chlorine produced from the chloride ion (Cl−) at the anodes. However, electrolysis with ozone aeration was found to be superior to the other processes, in terms of its energy efficiency in removing COD and its ability to remove COD completely, as a result of hydroxyl radical (˙OH) production via cathodic reduction of ozone.
Use of Chemical Coagulants to Control Fouling Potential for Wastewater Membrane Bioreactor Processes
Authors: Fan Fengshen , Zhou Hongde , Husain Hadi
Published: September 2007

Chemical coagulation with ferric chloride, alum, and an organic polymer were used to control the fouling potential of mixed liquors for submerged membrane bioreactor (MBR) processes in treating municipal wastewater. Their filterability was evaluated using a submerged hollow fiber ultrafiltration apparatus operated in constant permeate flux mode. The collected transmembrane pressures over filtration time were used to calculate the membrane fouling rates. The results showed that coagulation pretreatment can reduce fouling rates when MBRs were operated above the critical flux. Even though coagulation with the organic polymer formed larger mixed liquor suspended solids particles and had shorter time‐to‐filtration than those with ferric chloride and alum, the filterability for membrane filtration were similar, indicating that the membrane fouling in MBR systems was mainly controlled by the concentration of smaller colloidal particles.
Interaction Between Munc13-1 and RIM Is Critical for Glucagon-Like Peptide-1–Mediated Rescue of Exocytotic Defects in Munc13-1–Deficient Pancreatic β-Cells
Authors: Kwan Edwin P. , Xie Li , Sheu Laura , Ohtsuka Toshihisa , Gaisano Herbert Y.
Published: September 2007

OBJECTIVE—Glucagon-like peptide-1 (GLP-1) rescues insulin secretory deficiency in type 2 diabetes partly via cAMP actions on exchange protein directly activated by cAMP (Epac2) and protein kinase A (PKA)-activated Rab3A-interacting molecule 2 (Rim2). We had reported that haplodeficient Munc13-1+/− mouse islet β-cells exhibited reduced insulin secretion, causing glucose intolerance. Munc13-1 binds Epac2 and Rim2, but their functional interactions remain unclear.

RESEARCH DESIGN AND METHODS—We used Munc13-1+/− islet β-cells to examine the functional interactions between Munc13-1 and Epac2 and PKA. GLP-1 stimulation of Munc13-1+/− islets normalized the reduced biphasic insulin secretion by its actions on intact islet cAMP production and normal Epac2 and Rim2 levels.

RESULTS—To determine which exocytotic steps caused by Munc13-1 deficiency are rescued by Epac2 and PKA, we used patch-clamp capacitance measurements, showing that 1) cAMP restored the reduced readily releasable pool (RRP) and partially restored refilling of a releasable pool of vesicles in Munc13-1+/− β-cells, 2) Epac-selective agonist [8-(4-chloro-phenylthio)-2′-O-methyladenosine-3′,5′-cyclic monophosphate] partially restored the reduced RRP and refilling of a releasable pool of vesicles, and 3) PKA blockade by H89 (leaving Epac intact) impaired cAMP ability to restore the RRP and refilling of a releasable pool of vesicles. Conversely, PKA-selective agonist (N6-benzoyladenosine-cAMP) completely restored RRP and partially restored refilling of a releasable pool of vesicles. To determine specific contributions within Epac-Rim2–Munc13-1 interaction sites accounting for cAMP rescue of exocytosis caused by Munc13-1 deficiency, we found that blockade of Rim2–Munc13-1 interaction with Rim-Munc13-1–binding domain peptide abolished cAMP rescue, whereas blockade of Epac-Rim2 interaction with Rim2-PDZ peptide only moderately reduced refilling with little effect on RRP.

CONCLUSIONS—cAMP rescue of priming defects caused by Munc13-1 deficiency via Epac and PKA signaling pathways requires downstream Munc13-1–Rim2 interaction.
Cideb Regulates Diet-Induced Obesity, Liver Steatosis, and Insulin Sensitivity by Controlling Lipogenesis and Fatty Acid Oxidation
Authors: Li John Zhong , Ye Jing , Xue Bofu , Qi Jingzhong , Zhang Jing , Zhou Zhihong , Li Qing , Wen Zilong , Li Peng
Published: September 2007

OBJECTIVE—Our previous study suggests that Cidea, a member of Cide family proteins that share sequence homology with the DNA fragmentation factor and are expressed at high levels in brown adipose tissue, plays an important role in the development of obesity. Cideb, another member of Cide family protein, is highly expressed in the liver. We would like to understand the physiological role of Cideb in the regulation of energy expenditure and lipid metabolism.

RESEARCH DESIGN AND METHODS—We generated Cideb-null mice by homolog recombination and then fed both wild-type and Cideb-null mice with high-fat diet (58% fat). We then characterized the animals’ adiposity index, food intake, whole-body metabolic rate, liver morphology, rate of fatty acid synthesis and oxidation, insulin sensitivity, and gene expression profile.

RESULTS— Cideb-null mice had lower levels of plasma triglycerides and free fatty acids and were resistant to high-fat diet–induced obesity and live steatosis. In addition, Cideb mutant mice displayed significantly increased insulin sensitivity and enhanced rate of whole-body metabolism and hepatic fatty acid oxidation. More importantly, Cideb-null mice showed decreased lipogenesis and reduced expression levels of acetyl-CoA carboxylase, fatty acid synthase, and stearol-CoA desaturase. We further demonstrated that expression levels of sterol response element binding protein 1c was significantly decreased in Cideb-deficient mice.

CONCLUSIONS—Our data demonstrate that Cideb is a novel important regulator in lipid metabolism in the liver. Cideb may represent a new therapeutic target for the treatment of obesity, diabetes, and liver steatosis.
Central Insulin Regulates Heart Rate and Arterial Blood Flow
Authors: Cabou Cendrine , Cani Patrice D. , Campistron Gérard , Knauf Claude , Mathieu Caroline , Sartori Claudio , Amar Jacques , Scherrer Urs , Burcelin Rémy
Published: September 2007

OBJECTIVE—Central neural insulin regulates glucose homeostasis, but less is known about its cardiovascular effects. Endothelial nitric oxide synthase (eNOS)-derived nitric oxide (NO) represents a molecular link between metabolic and cardiovascular disease. Its role in the central nervous system remains to be determined. We studied the effects of central insulin infusion on femoral arterial blood flow and heart rate in normal chow–fed, high-fat diet–fed diabetic, and eNOS-null mice.

RESEARCH DESIGN AND METHODS —We recorded heart rate and femoral blood flow (ultrasonic flow probe) during 3-h central insulin infusion in conscious, freely moving mice. To study the role of NO in this setting, we assessed total and phosphorylated eNOS in the hypothalamus and examined the effects of brain infusion of NO donors/NOS inhibitors on cardiovascular responsiveness to central insulin in these experimental mouse models.

RESULTS —In normal mice, central insulin rapidly increased heart rate by 30% and more progressively increased blood flow by 40%. In high-fat diet–fed mice, the cardiovascular effects of insulin were blunted and associated with a 50% reduction of the total and phosphorylated eNOS expression in the hypothalamus, suggesting a causal link. In line with this hypothesis, in eNOS-null mice and central NG-monomethyl-l-arginine–infused normal mice, the cardiovascular effects of insulin were abolished, whereas central NO donor infusion restored these effects in eNOS-null mice. In high-fat diet–fed mice, central NO donor infusion mimicked the cardiovascular responses evoked by central insulin in normal mice.

CONCLUSIONS —Central insulin has cardiovascular effects in conscious, freely moving mice that are mediated, at least in part, by central neural eNOS. These effects are impaired in insulin-resistant high-fat diet–fed mice.