bluuebunny/crossref_metadata_2025 huggingface dataset:
Stress Corrosion Cracking of Single‐Crystal Tetragonal ZrO2(Er2O3)
Authors: Ridruejo Alvaro , Pastor José Y. , LLorca Javier , Sayir A. , Orera V. M.
Published: June 2006

The flexure strength of partially‐stabilized tetragonal ZrO2(Er2O3) single‐crystal monofilaments manufactured by the laser‐heated floating zone method was measured as a function of the environment (air versus water) and temperature (from 25° to 800°C) at loading rates spanning three orders of magnitude to ascertain their susceptibility to the environmental conditions. These mechanical tests were completed with parallel tests on fully annealed monofilaments (to relieve the thermal residual stresses induced during growth) and by detailed analysis of the fracture surfaces using scanning electron microscopy and micro‐Raman spectroscopy. While environmental susceptibility of ZrO2(Y2O3) in previous investigations was always associated with the destabilization of the tetragonal phase, monoclinic phase was not detected on the fracture surfaces of the ZrO2(Er2O3) monofilaments and it was concluded that slow crack growth in this material at high temperature or immersed in water was due to stress corrosion cracking.
EVALUATION OF ISO METHOD AND VIDAS AUTOMATED SYSTEM FOR IDENTIFYING LISTERIA AND SALMONELLA IN SELECTED FOODS
Authors: OKTAY HATICE IMGE , HEPERKAN DILEK
Published: June 2006

In this study, the materials used were the dairy products cheese and butter and the baked potatoes consumed with both of these products as toppings. All samples obtained from the Istanbul market were examined for the presence of Listeria monocytogenes and Salmonella microorganisms with the International Organization for Standardization (ISO) 11290 and 6579 methods, respectively, and mini‐The Vitek Immuno Diagnostic Assay System (VIDAS).

L. monocytogenes was not found in the butter and baked potato samples, while it was identified in three of the cheese samples. The Salmonella microorganism was not observed in any of the samples; however, other Enterobacteriaceae family members were isolated.

An inoculation study with L. monocytogenes and Salmonella Typhi using the same samples did not find any difference in the efficiency of ISO and mini‐VIDAS methods with respect to identifying Salmonella. However, mini‐VIDAS was determined to be more efficient for identifying L. monocytogenes in samples with a low bacterial count.
RAPID RELEASE OF PLASMIDS FROM LIVE OR DEAD ESCHERICHIA COLI CELLS
Authors: FENG FAN , WANG SHULI , CHEN ZHENLANG , LIU QIUYUN
Published: June 2006

A protocol for the rapid release of plasmids from live or dead Escherichia coli cells is described. A simple 1‐min boiling can eradicate all live bacteria, and supernatant can be efficiently transformed back to another E. coli strain or to Saccharomyces cerevisiae. Plasmids can be reliably recovered from dead cells by this procedure.
Endogenous Monoamine Receptor Activation Is Essential for Enabling Persistent Sodium Currents and Repetitive Firing in Rat Spinal Motoneurons
Authors: Harvey P. J. , Li X. , Li Y. , Bennett D. J.
Published: June 2006

The spinal cord and spinal motoneurons are densely innervated by terminals of serotonin (5-HT) and norepinephrine (NE) neurons arising mostly from the brain stem, but also from intrinsic spinal neurons. Even after long-term spinal transection (chronic spinal), significant amounts (10%) of 5-HT and NE (monoamines) remain caudal to the injury. To determine the role of such endogenous monoamines, we blocked their action with monoamine receptor antagonists and measured changes in the sodium currents and firing in motoneurons. We focused on persistent sodium currents (Na PIC) and sodium spike properties because they are critical for enabling repetitive firing in motoneurons and are facilitated by monoamines. Intracellular recordings were made from motoneurons in the sacrocaudal spinal cord of normal and chronic spinal rats (2 mo postsacral transection) with the whole sacrocaudal cord acutely removed and maintained in vitro (cords from normal rats termed acute spinal). Acute and chronic spinal rats had TTX-sensitive Na PICs that were respectively 0.62 ± 0.76 and 1.60 ± 1.04 nA, with mean onset voltages of −63.0 ± 5.6 and −64.1 ± 5.4 mV, measured with slow voltage ramps. Application of 5-HT2A, 5-HT2C, and α1-NE receptor antagonists (ketanserin, RS 102221, and WB 4101, respectively) significantly reduced the Na PICs, and a combined application of these three monoamine antagonists completely eliminated the Na PIC, in both acute and chronic spinal rats. Likewise, reduction of presynaptic transmitter release (including 5-HT and NE) with long-term application of cadmium also eliminated the Na PIC. Associated with the elimination of the Na PIC in monoamine antagonists, the motoneurons lost their ability to fire during slow current ramps. At this point, the spike evoked by antidromic stimulation was not affected, suggesting that activation of the transient sodium current was not impaired. However, the spike evoked after a slow ramp depolarization was slightly reduced in height and rate-of-rise, suggesting decreased sodium channel availability as a result of increased channel inactivation. These results suggest that endogenous monoamine receptor activation is critical for enabling the Na PIC and decreasing sodium channel inactivation, ultimately enabling steady repetitive firing in both normal and chronic spinal rats.
Effect of Conantokin G on NMDA Receptor–Mediated Spontaneous EPSCs in Cultured Cortical Neurons
Authors: Alex Anitha B. , Baucum Anthony J. , Wilcox Karen S.
Published: June 2006

Conantokin G (Con G), derived from the venom of Conus geographus, is the most characterized natural peptide antagonist targeted to N-methyl-d-aspartate (NMDA) receptors. Although Con G is known to bind to the glutamate binding site on the NR2 subunit of the receptor, it is unclear whether it can allosterically modulate the function of the receptor through the glycine binding site on the NR1 subunit. This study was designed to evaluate the action of Con G on NMDA receptor–mediated spontaneous excitatory postsynaptic currents (sEPSCs) and its modulation by glycine in cultured cortical neurons (13–19 days in vitro) using the whole cell patch-clamp technique. Con G inhibited NMDA receptor–mediated sEPSCs in a concentration-dependent manner. Also, the potency of Con G decreased as a function of time in culture. The inhibition of EPSCs observed after application of Con G in the presence of high (10 μM) and nominal (no added) concentrations of glycine was not different at 13 days in vitro (DIV). Furthermore, similar results were obtained with experiments on Con G–induced inhibition of NMDA-evoked whole cell currents. These results indicate that glycine concentrations do not have a direct effect on Con G–induced inhibition of NMDA currents. In addition, age dependency in the action of Con G on cortical neurons in vitro suggests that this model system would be useful in examining the effects of different agonists/antagonists on native synaptic NMDA receptors.
Independent component analysis reveals new and biologically significant structures in micro array data
Authors: Frigyesi Attila , Veerla Srinivas , Lindgren David , Höglund Mattias
Published: June 2006

Background

An alternative to standard approaches to uncover biologically meaningful structures in micro array data is to treat the data as a blind source separation (BSS) problem. BSS attempts to separate a mixture of signals into their different sources and refers to the problem of recovering signals from several observed linear mixtures. In the context of micro array data, "sources" may correspond to specific cellular responses or to co-regulated genes.

Results

We applied independent component analysis (ICA) to three different microarray data sets; two tumor data sets and one time series experiment. To obtain reliable components we used iterated ICA to estimate component centrotypes. We found that many of the low ranking components indeed may show a strong biological coherence and hence be of biological significance. Generally ICA achieved a higher resolution when compared with results based on correlated expression and a larger number of gene clusters with significantly enriched for gene ontology (GO) categories. In addition, components characteristic for molecular subtypes and for tumors with specific chromosomal translocations were identified. ICA also identified more than one gene clusters significant for the same GO categories and hence disclosed a higher level of biological heterogeneity, even within coherent groups of genes.

Conclusion

Although the ICA approach primarily detects hidden variables, these surfaced as highly correlated genes in time series data and in one instance in the tumor data. This further strengthens the biological relevance of latent variables detected by ICA.
Simple sequence proteins in prokaryotic proteomes
Authors: Subramanyam Mekapati Bala , Gnanamani Muthiah , Ramachandran Srinivasan
Published: June 2006

Background

The structural and functional features associated with Simple Sequence Proteins (SSPs) are non-globularity, disease states, signaling and post-translational modification. SSPs are also an important source of genetic and possibly phenotypic variation. Analysis of 249 prokaryotic proteomes offers a new opportunity to examine the genomic properties of SSPs.

Results

SSPs are a minority but they grow with proteome size. This relationship is exhibited across species varying in genomic GC, mutational bias, life style, and pathogenicity. Their proportion in each proteome is strongly influenced by genomic base compositional bias. In most species simple duplications is favoured, but in a few cases such as Mycobacteria, large families of duplications occur.

Amino acid preference in SSPs exhibits a trend towards low cost of biosynthesis. In SSPs and in non-SSPs, Alanine, Glycine, Leucine, and Valine are abundant in species widely varying in genomic GC whereas Isoleucine and Lysine are rich only in organisms with low genomic GC. Arginine is abundant in SSPs of two species and in the non-SSPs of Xanthomonas oryzae. Asparagine is abundant only in SSPs of low GC species. Aspartic acid is abundant only in the non-SSPs of Halobacterium sp NRC1. The abundance of Serine in SSPs of 62 species extends over a broader range compared to that of non-SSPs. Threonine(T) is abundant only in SSPs of a couple of species. SSPs exhibit preferential association with Cell surface, Cell membrane and Transport functions and a negative association with Metabolism. Mesophiles and Thermophiles display similar ranges in the content of SSPs.

Conclusion

Although SSPs are a minority, the genomic forces of base compositional bias and duplications influence their growth and pattern in each species. The preferences and abundance of amino acids are governed by low biosynthetic cost, evolutionary age and base composition of codons. Abundance of charged amino acids Arginine and Aspartic acid is severely restricted. SSPs preferentially associate with cell surface and interface functions as opposed to metabolism, wherein proteins of high sequence complexity with globular structures are preferred. Mesophiles and Thermophiles are similar with respect to the content of SSPs. Our analysis serves to expandthe commonly held views on SSPs.
Protocol for stage 1 of the GaP study (Genetic testing acceptability for Paget's disease of bone): an interview study about genetic testing and preventive treatment: would relatives of people with Paget's disease want testing and treatment if they were available?
Authors: Langston Anne L , Johnston Marie , Robertson Clare , Campbell Marion K , Entwistle Vikki A , Marteau Theresa M , McCallum Marilyn , Ralston Stuart H
Published: June 2006

Background

Paget's disease of bone (PDB) is characterised by focal increases in bone turnover, affecting one or more bones throughout the skeleton. This disrupts normal bone architecture and causes pain, deformity, deafness, osteoarthritis, and fractures.

Genetic factors are recognised to play a role in PDB and it is now possible to carry out genetic tests for research. In view of this, it is timely to investigate the clinical potential for a programme of genetic testing and preventative treatment for people who have a family history of PDB, to prevent or delay the development of PDB.

Evidence from non-genetic conditions, that have effective treatments, demonstrates that patients' beliefs may affect the acceptability and uptake of treatment. Two groups of beliefs (illness and treatment representations) are likely to be influential.

Illness representations describe how people see their illness, as outlined in Leventhal's Self-Regulation Model. Treatment representations describe how people perceive potential treatment for their disease. People offered a programme of genetic testing and treatment will develop their own treatment representations based on what is offered, but the beliefs rather than the objective programme of treatment are likely to determine their willingness to participate. The Theory of Planned Behaviour is a theoretical model that predicts behaviours from people's beliefs about the consequences, social pressures and perceived control over the behaviour, including uptake of treatment.

Methods/design

This study aims to examine the acceptability of genetic testing, followed by preventative treatment, to relatives of people with PDB. We aim to interview people with Paget's disease, and their families, from the UK. Our research questions are:

1. What do individuals with Paget's diseasethink would influence the involvement of their relatives in a programme of genetic testing and preventative treatment?

2. What do relatives of Paget's disease sufferersthink would influence them in accepting an offer of a programme of genetic testing and preventative treatment?

Discussion

Our research will be informed by relevant psychological theory: primarily the Self-Regulation Model and the Theory of Planned Behaviour. The results of these interviews will inform the development of a separate questionnaire-based study to explore these research questions in greater detail.
Safeguarding the Promise of Production Outsourcing
Authors: Amaral Jason , Billington Corey A. , Tsay Andy A.
Published: June 2006

Today’s product companies (original equipment manufacturers, or OEMs) increasingly outsource production, especially when the activities are asset intensive or require process technologies characterized by rapid innovation. When such an OEM also outsources the procurement of the required materials, especially to the party providing the production services, the OEM risks unpleasant surprises, such as unauthorized part or supplier substitutions, overbilling, mistreatment of the supply base, and the loss of the OEM’s procurement leverage. Based on supply chain audits and interviews in numerous industries, we propose and analyze strategies for preventing these outcomes when outsourcing production. We recommend that OEMs carefully consider the underlying means, motives, and opportunities of the service providers when deciding which activities to outsource and how to establish effective business controls. Firms such as Hewlett-Packard, Motorola, and Dell have implemented these ideas.
Achieving Breakthrough Service Delivery Through Dynamic Asset Deployment Strategies
Authors: Cohen Morris A. , Agrawal Narendra , Agrawal Vipul
Published: June 2006

Many firms have shifted their focus from their products to their customers and the value derived from owning and using the products. They see after-sales service as an important source of revenue and profit, customer acquisition and retention, and competitive differentiation. However, they also find it challenging to manage their service-supply chain. Service organizations must position and manage service-supply-chain resources optimally to support the delivery of after-sales service. They must also develop capabilities to respond rapidly to the demand for service in a cost-effective manner. To succeed in implementing a service-centric strategy, firms must determine what items in their products’ service bill-of-material hierarchy should be deployed throughout their geographical hierarchy of service support locations. They must make these complex and interrelated decisions in anticipation of service demand, which is uncertain. Firms must also be flexible and should understand the mechanisms in a service-supply chain needed to fulfill customers’ demands for service and the resulting demands for support assets and capacities. Dynamic asset deployment (DAD), a collection of management policies that promote this flexibility, can be used to develop the capabilities needed to effectively and profitably deliver services. These policies require a real-options-based optimization approach to decision making.
Statistical Analysis of Nonmetallic Inclusions for the Estimation of Rolling Contact Fatigue Range and Quality Control of Bearing Steel
Authors: Girodin D , Dudragne G , Courbon J , Vincent A
Published: June 2006

The cleanliness of bearing steels is a critical factor that influences directly the rolling contact fatigue performance and other mechanical properties of bearings. Hence, the evaluation of nonmetallic inclusions is a very important issue for steelmakers, bearing producers, and users. The material qualification procedure includes classical inclusion rating and rolling contact fatigue tests as acceptance tests for evaluating steel suppliers and ensuring the required bearing performance. The evolution of steel cleanliness had led to an increase in fatigue life so that running time of rolling contact fatigue tests have been considerably extended, until they became too time and cost consuming for a realistic qualification. In this paper, quantitative metallographic evaluation of the inclusion cleanliness used to collect data on the size, type, and expected number of inclusions in small samples is presented. The data were analyzed using Statistics of Extreme Values (SEV) and the results were used to extrapolate in larger samples representative of actual volumes of material involved in rolling contact fatigue tests and were related to the fatigue life of bearing steels from different suppliers. This method gives useful and reliable statistical data on inclusions for evaluating the performance level under rolling contact fatigue and defines the required cleanliness characteristics for bearing steels qualification. Other information of this work is the ability of the statistical inclusion rating to serve as a substitute for rolling contact fatigue tests to forecast the performance level of bearing steels.
Violent Crime and Victim Compensation: Implications for Social Justice
Authors: Smith Hayden P.
Published: June 2006

Restorative justice offers several innovative methods designed to heal the injury that the offender may have caused to the victim. One of these innovative methods is victim compensation, a form of income redistribution designed to redistribute wealth from offenders to victims of crime. Restitution, particularly through the Victim of Crime Act (VOCA), is a needs-based form of justice designed to assist the most needy victims of violent crime. Recent studies suggest that while state-level compensation programs may target poor, young, African American men, compensation at the national level tends to be received more by older, White women who experienced domestic violence. The author suggests that this disparity between state and local resource distribution in the allocation of victim compensation is a reflection of the ideological differences between the established theoretical frameworks of liberalism and radical feminism.
X-Ray Computed Microtomography Studies of Fluid Partitioning in Drainage and Imbibition Before and After Gel Placement: Disproportionate Permeability Reduction
Authors: Seright R.S. , Prodanovic Masa , Lindquist W. Brent
Published: June 2006

X-ray computed microtomography (XMT) was used to establish why pore-filling Cr(III)-acetate-HPAM gels reduced permeability to water much more than to oil. Our results suggest that permeability to water was reduced to low values because water must flow through gel itself, whereas oil pressing on the gel in Berea sandstone or porous polyethylene forced pathways by dehydration—leading to relatively high permeability to oil. In very permeable sandpacks, data from other researchers support ripping or extrusion mechanisms for creating oil pathways.

Our XMT studies provide interesting insights into imbibition and drainage processes in water-wet and oil-wet porous media even before gel placement. Many of our observations were consistent with conventional wisdom. However, some were unexpected. Residual wetting-phase (water) saturations in Berea were surprisingly low-valued in small pores. We attribute this to surface roughness caused by clay coating on Berea's pore walls, which allowed efficient water drainage from small pores during oil injection.
Accurate, Efficient Quantification of Uncertainty for Flow in Heterogeneous Reservoirs Using the KLME Approach
Authors: Lu Zhiming , Zhang Dongxiao
Published: June 2006

Accurate modeling of flow in oil/gas reservoirs requires a detailed description of reservoir properties such as permeability and porosity. However, such reservoirs are inherently heterogeneous and exhibit a high degree of spatial variability in medium properties. Significant spatial heterogeneity and a limited number of measurements lead to uncertainty in characterization of reservoir properties and thus to uncertainty in predicting flow in the reservoirs. As a result, the equations that govern flow in such reservoirs are treated as stochastic partial differential equations. The current industrial practice is to tackle the problem of uncertainty quantification by Monte Carlo simulations (MCS). This entails generating a large number of equally likely random realizations of the reservoir fields with parameter statistics derived from sampling, solving deterministic flow equations for each realization, and post-processing the results over all realizations to obtain sample moments of the solution. This approach has the advantages of applying to a broad range of both linear and nonlinear flow problems, but it has a number of potential drawbacks. To properly resolve high-frequency space-time fluctuations in random parameters, it is necessary to employ fine numerical grids in space-time. Therefore, the computational effort for each realization is usually large, especially for large-scale reservoirs. As a result, a detailed assessment of the uncertainty associated with flow-performance predictions is rarely performed.

In this work, we develop an accurate yet efficient approach for solving flow problems in heterogeneous reservoirs. We do so by obtaining higher-order solutions of the prediction and the associated uncertainty of reservoir flow quantities using the moment-equation approach based on Karhunen-Loéve decomposition (KLME). The KLME approach is developed on the basis of the Karhunen-Loéve (KL) decomposition, polynomial expansion, and perturbation methods. We conduct MCS and compare these results against different orders of approximations from the KLME method. The 3D computational examples demonstrate that this KLME method is computationally more efficient than both Monte Carlo simulations and the conventional moment-equation method. The KLME approach allows us to evaluate higher-order terms that are needed for highly heterogeneous reservoirs. In addition, like the Monte Carlo method, the KLME approach can be implemented with existing simulators in a straightforward manner, and they are inherently parallel. The efficiency of the KLME method makes it possible to simulate fluid flow in large-scale heterogeneous reservoirs.
On Stop-Loss Premiums for the Individual Model
Authors: Kaas R. , van Heerwaarden A. E. , Goovaerts M. J.
Published: June 2006

It is shown how the upper bounds for stop-loss premiums (and approximations to tail probabilities) obtained by replacing the individual model for a portfolio of risks by the collective model can be improved upon at the cost of only slightly more computer time. The method used is simply to keep a restricted number of large risks as they are instead of approximating them by a compound Poisson distribution. In a real-life example, the relative error in the stop-loss premium is shown to be reduced drastically by keeping only 10 out of 743 risks unchanged.
Produits financiers et determination de la prime glissante de traites non proportionnels
Authors: Levi Charles
Published: June 2006

Financial income play a big part for the calculation of the minimum premium and maximum premium of a sliding scale for non-proportional treaties. The aggregate loss for the XL is supposed to be a compound Poisson process. It is computed by Panjer's Algorithm. Some numerical results are shown for different values of the claims number and the interest rate.
Estimators and Bootstrap Confidence Intervals for Ruin Probabilities
Authors: Hipp Christian
Published: June 2006

For the infinite time ruin probability in the classical risk process, efficient estimators are proposed in cases in which the claim amount distribution is unknown. Confidence intervals are computed which are based on normal approximations or on the bootstrap method. The procedures are checked in a Monte-Carlo study.
On an Integral Equation for Discounted Compound – Annuity Distributions
Authors: Ramsay Colin M.
Published: June 2006

We consider a risk generating claims for a period of N consecutive years (after which it expires), N being an integer valued random variable. Let Xk denote the total claims generated in the kth year, k ≥ 1. The Xk's are assumed to be independent and identically distributed random variables, and are paid at the end of the year. The aggregate discounted claims generated by the risk until it expires is defined as where υ is the discount factor. An integral equation similar to that given by Panjer (1981) is developed for the pdf of SN(υ). This is accomplished by assuming that N belongs to a new class of discrete distributions called annuity distributions. The probabilities in annuity distributions satisfy the following recursion:

where an is the present value of an n-year immediate annuity.
Mutual Reinsurance and Homogeneous Linear Estimation
Authors: Neuhaus Walther
Published: June 2006

The technique of risk invariant linear estimation from Neuhaus (1988) has been applied in the construction of a mutual quota share reinsurance pool between the subsidiary companies of the Storebrand Insurance Company, Oslo. The paper describes the construction of the reinsurance scheme.
Radiation curing of diacrylate glycerolate of bisphenol‐A in the presence of an organically modified montmorillonite for the production of flame‐resistant polymer–clay composites
Authors: Spadaro Giuseppe , Dispenza Clelia , Alessi Sabina , Tartaglione Giuseppina , Camino Giovanni
Published: June 2006

Polymerization of an acrylate derivative of bisphenol‐A by ionizing radiation in the presence of an organically modified montmorillonite was carried out in order to produce a flame‐retardant composite. The measurement of the thermal effect during irradiation indicates that radiation curing of pure resin and resin‐clay mixtures occurred in both cases. Moreover, differential scanning calorimetry and dynamic mechanical thermal analysis showed that a curing completion can be obtained by thermal curing after irradiation with a significant increase of the glass transition temperature. The morphology was investigated by X‐ray diffraction and transmission electron microscopy. These have indicated that gamma irradiation leads to the formation of a microcomposite structure after radiation curing. The flame resistant characteristics were studied by means of thermal gravimetric analysis under nitrogen and air and by cone calorimeter tests. In particular, thermal gravimetric analysis in air showed that the presence of the dispersed clay in the polymer matrix increases the oxidation temperature. This is attributed to the formation of a more stable char, due to a protective skin of clay aggregates that builds up on the surface of the volatilizing polymer matrix during thermal degradation which protects the charred polymer from reactions with oxygen. Finally, the cone calorimeter tests show a reduction of heat release of the clay‐polymer composite with respect to the neat resin. The contribution of the clay in reducing the rate of heat release is attributed to the dispersion of the filler that allows build‐up of an inorganic surface layer at a rate which is sufficient for effectively compete with the feeding of the flame with combustible pyrolysis products. © 2006 Wiley Periodicals, Inc. Adv Polym Techn 25: 109–120, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/adv.20063
Nicotine metabolizing genes GSTT1 and CYP1A1 in sudden infant death syndrome
Authors: Rand Casey M. , Weese‐Mayer Debra E. , Maher Brion S. , Zhou Lili , Marazita Mary L. , Berry‐Kravis Elizabeth M.
Published: June 2006

Exposure to tobacco, both to the developing fetus as well as in the postnatal period, has been identified as a key risk factor in the etiology of sudden infant death syndrome (SIDS). Polymorphisms in both the GSTT1 and CYP1A1 genes have been reported to impact the metabolic detoxification process for cigarette smoke and have been associated with low birth weight. Thus, expression of polymorphisms in these genes may account for the varying susceptibility to the adverse health consequences of tobacco exposure, including SIDS. We hypothesized that functional polymorphisms in GSTT1 (gene deletion) and CYP1A1 (m1, m2, and m3) might be associated with SIDS risk. DNA was prepared from 106 SIDS cases and 106 ethnicity‐ and gender‐matched controls using standard methods. Regions of interest were amplified using PCR, subjected to enzyme digestion, and analyzed on agarose gel. No association was observed between the GSTT1 gene deletion or the CYP1A1 m1, m2, and m3 polymorphisms with SIDS risk when considered independently or in combination. These results indicate that the GSTT1 gene deletion and polymorphisms of CYP1A1 are not responsible for increased SIDS risk in our dataset. However, because SIDS cases with confirmed history of nicotine exposure were limited (7/106 cases), a relationship that might be apparent in a cohort with a large subset of SIDS cases with known history of nicotine exposure cannot be ruled out. A prospective study of SIDS cases with nicotine exposure history is necessary to resolve the relationship between nicotine metabolizing genes and SIDS. © 2006 Wiley‐Liss, Inc.
Consanguineous marriage and congenital heart defects: A case‐control study in the neonatal period
Authors: Khalid Yunis , Ghina Mumtaz , Fadi Bitar , Fadi Chamseddine , May Kassar , Joseph Rashkidi , Makhoul Ghaith , Hala Tamim
Published: June 2006

The independent effect of consanguinity on the prevalence of congenital heart defects (CHDs), all and specific types, was investigated in newborns admitted to nine hospitals located in Beirut, Lebanon and members of the National Collaborative Perinatal Neonatal Network (NCPNN). Cases were 173 newborns admitted to the Neonatal Intensive Care Units (NICU) of participating hospitals during the 3‐year period from January 1, 2000 to December 31, 2002 and diagnosed during their hospital stay as having one or more CHD. Cases with chromosomal abnormalities were excluded. Cases with more than one CHD were assigned one principal malformation. Controls consisted of a random sample of 865 newborns without a CHD admitted to the NICU during the same period. After controlling for confounders, first cousin consanguinity remained significantly associated with an increased risk of CHD: infants born to first cousin marriages had a 1.8 times higher risk of having a CHD diagnosed at birth compared to those born to unrelated parents (95% CI: 1.1–3.1). In particular, first‐cousin marriage was a significant risk factor for ventricular septal defect (VSD), atrial septal defect (ASD), hypoplastic left heart (HLH), and single ventricle (SV). No association was found with d‐transposition of the great arteries, coarctation, pulmonary atresia (PA), atrioventricular septal defect (AVSD), and tetralogy of Fallot (TOF). The results of this study suggest a familial factor in the multifactorial etiology of CHDs. Additional epidemiologic and family‐based genetic studies are needed to understand the complex cause of CHDs. © 2006 Wiley‐Liss, Inc.
Signifying contortions: disavowal, the enigmatic signifier, and George W. Bush's credibility after 9/11
Authors: Wyatt Jean
Published: June 2006

“Signifying Contortions” attempts to account for Bush's credibility by reflecting on three psychological processes that lead people to tolerate the misleading and contradictory discourse of a leader. Laplanche's theory of the way children process the “enigmatic signifiers” coming from their parents explains why an authority figure's verbal fumblings and contradictions would evoke in his followers not only tolerance, but a deep attachment to him. Through a process of disavowal, the paper argues, certain signifiers related to 9/11 – such as “World Trade Center” – have been emptied of their meaning; President Bush's words serve as a fetish that seals over the gap made by these collective disavowals. Freud said that members of a group see in their leader the embodiment of each member's ego ideal; I claim that Bush both defends and embodies not the ego ideal described by Freud, but the nation's collective ideal ego, as that is described by Lacan. The three modes of contorted signifying function to preserve the idealized self‐image of the all‐good, all‐beneficent USA, which came under attack on 9/11. Copyright © 2006 John Wiley & Sons, Ltd.
Toward a model of the everyday life information needs of urban teenagers, part 1: Theoretical model
Authors: Agosto Denise E. , Hughes‐Hassell Sandra
Published: June 2006

This is the first part of a two‐part article that offers a theoretical and an empirical model of the everyday life information needs of urban teenagers. The qualitative methodology used to gather data for the development of the models included written surveys, audio journals, written activity logs, photographs, and semistructured group interviews. Twenty‐seven inner‐city teens aged 14 through 17 participated in the study. Data analysis took the form of iterative pattern coding using QSR NVivo 2 software (QSR International, 2002). The resulting theoretical model includes seven areas of urban teen development: the social self, the emotional self, the reflective self, the physical self, the creative self, the cognitive self, and the sexual self. The researchers conclude that the essence of teen everyday life information seeking (ELIS) is the gathering and processing of information to facilitate the teen‐to‐adulthood maturation process. ELIS is self‐exploration and world exploration that helps teens understand themselves and the social and physical worlds in which they live. This study shows the necessity of tying youth information‐seeking research to developmental theory in order to examine the reasons why adolescents engage in various information behaviors.
The role of the Internet in informal scholarly communication
Authors: Barjak Franz
Published: June 2006

The present analysis looks at how scientists use the Internet for informal scientific communication. It investigates the relationship between several explanatory variables and Internet use in a cross‐section of scientists from seven European countries and five academic disciplines (astronomy, chemistry, computer science, economics, and psychology). The analysis confirmed some of the results of previous U.S.‐based analyses. In particular, it corroborated a positive relationship between research productivity and Internet use. The relationship was found to be nonlinear, with very productive (nonproductive) scientists using the Internet less (more) than would be expected according to their productivity. Also, being involved in collaborative R&D and having large networks of collaborators is associated with increased Internet use. In contrast to older studies, the analysis did not find any equalizing effect whereby higher Internet use rates help to overcome the problems of potentially disadvantaged researchers. Obviously, everybody who wants to stay at the forefront of research and keep up‐to‐date with developments in their research fields has to use the Internet.
Very late thrombosis after drug‐eluting stents
Authors: Feres Fausto , Costa J. Ribamar , Abizaid Alexandre
Published: June 2006

Stent thrombosis is a rare but potentially fatal complication of percutaneous treatment of coronary disease. Its occurrence after drug eluting stent (DES) placement has raised concerns, especially when it occurs late after the stent implantation. The mechanisms of late thrombosis after DES have yet to be completely understood. By means of serial angiography and intravascular (IVUS) images we described a relatively new and unusual vessel response to drug‐eluting stents (e.g. huge positive remodeling in all vessel extension), leading to impressive late‐acquired incomplete stent apposition and finally causing stent thrombosis and acute myocardial infarction. After describing the two cases, one after Cypher stent implantation and one after Taxus stent implantation, we briefly reviewed the literature available on stent thrombosis with special emphasis on its late occurrence. © 2006 Wiley‐Liss, Inc.
Quantitative assessment of in‐stent dimensions: A comparison of 64 and 16 detector multislice computed tomography to intravascular ultrasound
Authors: Beohar Nirat , Robbins Joel D. , Cavanaugh Brendan J. , Ansari Asimul H. , Yaghmai Vahid , Carr James , Davidson Charles J.
Published: June 2006

Objectives:

To determine the utility of multislice computed tomography (MSCT) technology to evaluate coronary stent luminal diameter.

Background:

Stent metal induced “blooming” artifact makes quantitative coronary angiography by MSCT difficult. There is a paucity of data on the efficacy of using 64 and 16 detector MSCT in evaluating coronary stents.

Methods:

We evaluated four commercially available bare metal and polymer coated drug eluting stents using 64 and 16 detector MSCT for the following: (1) Strut density in Hounsfield's Units (Hu) using a 2 mm MIP; (2) In‐stent luminal diameter (ISLD) measured by MSCT compared to intravascular ultrasound (IVUS).

Results:

Increased strut thickness did not correlate with greater strut density as measured in Hu (R2 = 0.05, P = 0.29). The ISLD by 16 MSCT vs. IVUS is: Vision 1.63 ± 0.58 mm vs. 2.8 ± 0.0; Cypher 1.80 ± 0.00 vs. 2.9 ± 0.0; Taxus 1.87 ± 0.58 vs. 2.9 ± 0.0; Liberté 1.80 ± 0.10 vs. 3.0 ± 0.1 (P < 0.01). ISLD determined by 64 MSCT vs. IVUS is: Vision 1.73 ± 0.06 mm vs. 2.8 ± 0.0; Cypher 1.87 ± 0.12 vs. 2.9 ± 0.0; Taxus 1.77 ± 0.06 vs. 2.9 ± 0.0; Liberté 1.80 ± 0.10 vs. 3.0 ± 0.1 (P < 0.01).

Conclusions:

When compared to IVUS measurements, MSCT results in a significant, underestimation of ISLD. This consistent underestimation (even with 64 MSCT) limits the applicability of CT angiography to quantify in‐stent restenosis. © 2006 Wiley‐Liss, Inc.
Provisional T‐stenting and kissing balloon in the treatment of coronary bifurcation lesions: Results of the French multicenter “TULIPE” study
Authors: Brunel Philippe , Lefevre Thierry , Darremont Olivier , louvard Yves
Published: June 2006

Background:

In previous prospective studies, a strategy of (a) stenting of the main branch, (b) provisional T‐stenting of the side branch, and (c) final kissing balloon inflation, was associated with high success and low target lesion revascularization (TLR) rates on the long‐term.

Objectives:

To examine the performance of this strategy in a multicenter study.

Methods:

Consecutive patients were treated at 14 French medical centers for de novo coronary bifurcation lesions with the same technique used. Immediate results and clinically‐driven TLR at 7 months were examined.

Results:

The mean reference diameters of the main and side branches were 3.2 ± 0.6 mm and 2.4 ± 0.5 mm, respectively. The side branch was stented in 34% of patients. A <30% residual stenosis in the main branch was achieved in 99%, <50% in the side branch in 90%, and both in 89% of procedures. The in‐hospital major adverse cardiovascular event were a Q‐wave and 5 non‐Qwaves MI (0.54% and 2.7%). At 7 months of follow‐up, 3 patients (1.76%) had died, 1 suffered a non‐Q‐wave MI (0.59%), and 28 (15.88%) underwent TLR. By multivariate analysis, a lower left ventricular ejection fraction (OR: 0.934), moderate calcifications (OR: 7.86), and non‐use of the “jailed” wire technique (OR: 4.26) were associated with reinterventions during follow‐up.

Conclusions:

A strategy of provisional T‐stenting with a tubular stent and final kissing balloon angioplasty for the treatment of coronary bifurcation lesions was safe and associated with a low TLR rate at 7 months. This strategy should be applicable to the new era of drug eluting stents. © 2006 Wiley‐Liss, Inc.
MEK kinase 1 is a negative regulator of virus‐specific CD8+ T cells
Authors: Labuda Tord , Christensen Jan Pravsgaard , Rasmussen Susanne , Bonnesen Barbara , Karin Michael , Thomsen Allan Randrup , Ødum Niels
Published: June 2006

MEK kinase 1 (MEKK1) is a potent JNK‐activating kinase, a regulator of T helper cell differentiation, cytokine production and proliferation in vitro. Using mice deficient for MEKK1 activity (Mekk1ΔKD) exclusively in their hematopoietic system, we show that MEKK1 has a negative regulatory role in the generation of a virus‐specific immune response. Mekk1ΔKD mice challenged with vesicular stomatitis virus (VSV) showed a fourfold increase in splenic CD8+ T cell numbers. In contrast, the number of splenic T cells in infected WT mice was only marginally increased. The CD8+ T cell expansion in Mekk1ΔKD mice following VSV infection is virus‐specific and the frequency of virus‐specific T cells is significantly higher (more than threefold) in Mekk1ΔKD as compared to WT animals. Moreover, the hyper‐expansion of T cells seen in Mekk1ΔKD mice after VSV infection is a result of increased proliferation, since a significantly higher percentage of virus‐specific Mekk1ΔKD CD8+ T cells incorporated BrdU as compared to virus‐specific WT CD8+ T cells. In contrast, similar levels of apoptosis were detected in Mekk1ΔKD and WT T cells following VSV infection. These results strongly suggest that MEKK1 plays a negative regulatory role in the expansion of virus‐specific CD8+ T cells in vivo.
Decreased specific CD8+ T cell cross‐reactivity of antigen recognition following vaccination with Melan‐A peptide
Authors: Appay Victor , Speiser Daniel E. , Rufer Nathalie , Reynard Severine , Barbey Catherine , Cerottini Jean‐Charles , Leyvraz Serge , Pinilla Clemencia , Romero Pedro
Published: June 2006

The aim of T cell vaccines is the expansion of antigen‐specific T cells able to confer immune protection against pathogens or tumors. Although increase in absolute cell numbers, effector functions and TCR repertoire of vaccine‐induced T cells are often evaluated, their reactivity for the cognate antigen versus their cross‐reactive potential is rarely considered. In fact, little information is available regarding the influence of vaccines on T cell fine specificity of antigen recognition despite the impact that this feature may have in protective immunity. To shed light on the cross‐reactive potential of vaccine‐induced cells, we analyzed the reactivity of CD8+ T cells following vaccination of HLA‐A2+ melanoma patients with Melan‐A peptide, incomplete Freund's adjuvant and CpG‐oligodeoxynucleotide adjuvant, which was shown to induce strong expansion of Melan‐A‐reactive CD8+ T cells in vivo. A collection of predicted Melan‐A cross‐reactive peptides, identified from a combinatorial peptide library, was used to probe functional antigen recognition of PBMC ex vivo and Melan‐A‐reactive CD8+ T cell clones. While Melan‐A‐reactive CD8+ T cells prior to vaccination are usually constituted of widely cross‐reactive naive cells, we show that peptide vaccination resulted in expansion of memory T cells displaying a reactivity predominantly restricted to the antigen of interest. Importantly, these cells are tumor‐reactive.
Distinct orientation of the alloreactive monoclonal CD8 T cell activation program by three different peptide/MHC complexes
Authors: Auphan‐Anezin Nathalie , Mazza Catherine , Guimezanes Annick , Barrett‐Wilt Gregory A. , Montero‐Julian Felix , Roussel Alain , Hunt Donald F. , Malissen Bernard , Schmitt‐Verhulst Anne‐Marie
Published: June 2006

We have characterized three different programs of activation for alloreactive CD8 T cells expressing the BM3.3 TCR, their elicitation depending on the characteristics of the stimulating peptide/MHC complex. The high‐affinity interaction between the TCR and the Kb‐associated endogenous peptide pBM1 (INFDFNTI) induced a complete differentiation program into effector cells correlated with sustained ERK activation. The Kbm8 variant elicited a partial activation program with delayed T cell proliferation, poor CTL activity and undetectable ERK phosphorylation; this resulted from a low‐avidity interaction of TCR BM3.3 with a newly identified endogenous peptide, pBM8 (SQYYYNSL). Interestingly, mismatched pBM1/Kbm8 complexes induced a split response in BM3.3 T cells, with total reconstitution of T cell proliferation but defective generation of CTL activity that was correlated with strong but shortened ERK phosphorylation. Crystal structures highlight the molecular basis for the higher stability of pBM8/Kbm8 compared to pBM1/Kbm8 complexes that exist in two conformers. This study illustrates the importance of the stability of both peptide/MHC and peptide/MHC‐TCR interactions for induction of sustained signaling required to induce optimal CTL effector functions. Subtle allelic structural variations, amplified by peptide selection, may thus orient distinct outcomes of alloreactive TCR‐based therapies.
Cover Picture: An Efficient Route to Stable Room‐Temperature Liquid‐Crystalline Triphenylenes (Eur. J. Org. Chem. 13/2006)
Authors: Bock Harald , Rajaoarivelo Mbolotiana , Clavaguera Simon , Grelet Éric
Published: June 2006

The cover picture shows the dendritic growth in hexagonal symmetry of a columnar liquid‐crystalline triphenylenetetracarboxylic alkyl ester on a silicon wafer, seen by differential interference contrast microscopy in reflection. This ester, straightforwardly obtained by regioselective formylation of 2,6,10‐trimethyltriphenylene, is a member of the elusive class of electron‐deficient, room‐temperature columnar liquid crystals that are studied for use in organic optoelectronic devices. Details are discussed in the Short Communication by H. Bock et al. on p. 2889 ff.
Interpolating local snow depth data: an evaluation of methods
Authors: López‐Moreno J. I. , Nogués‐Bravo D.
Published: June 2006

Snow depth measurements have been taken since 1986 at 106 snow poles distributed in the Spanish Pyrenees. Here, we compared the capacity of several local, geostatistical and global interpolator methods for mapping the spatial distribution of averaged snowpack (1986–2000) and the snowpack distribution in two single years with different climatic conditions. The error estimators indicate that the terrain complexity of the area makes it difficult to apply local and geostatistical methods satisfactorily. Regression‐tree models provide an accurate description of the data set used (the calibration phase), but they show a relatively low predictive capability for the study case (the validation phase). Using linear regression and generalized additive models (GAMs), we achieved more robust estimations than by means of a regression‐tree model. The GAMs give the most accurate prediction because they consider the non‐linear relationships between snowpack and the external characteristics (physical features) of the sampling points. Copyright © 2006 John Wiley & Sons, Ltd.