bluuebunny/crossref_metadata_2025 huggingface dataset:
An Experimental Approach to Continuous Dieless Wire Drawing (Variant A) Using ELI Ti–6Al–4V Alloy
Authors: Naughton M. D. , Tiernan P.
Published: March 2009

This research paper describes a specifically constructed Variant A continuous dieless wire-drawing machine to experimentally determine the principal processing parameters for dieless wire drawing using extra low interstitial Ti–6Al–4V wire alloy. It was experimentally determined that the process was limited by the ratio of the ingoing and outgoing axial velocities, also known as the reduction ratio R and influenced by the primary drawing velocity V1. Reductions of up to 36% per pass wire in cross-sectional area (CSA) were achieved. However, a direct relationship between the wire diameter variation and an increase in overall achievable reduction in CSA was observed. The separation distance between the wire heating and cooling devices (S) was identified as one of the principal governing process parameters. It was found that processing in an inert gas environment led to an increased reduction on CSA of approximately 3% per pass when compared with processing in compressed air. This was attributed to a reduction in surface oxidation and stress cracking. The experimentally determined results showed excellent agreement with a proposed mathematical model. It was also determined that the calculated strain rate for the process fell within the boundaries of previously determined strain rates for this particular alloy. The successful operation of this experimental machine effectively illustrates the possible commercial validity of continuous dieless wire drawing.
Grain Level Dwell Fatigue Crack Nucleation Model for Ti Alloys Using Crystal Plasticity Finite Element Analysis
Authors: Kirane Kedar , Ghosh Somnath , Groeber Mike , Bhattacharjee Amit
Published: March 2009

A microstructure sensitive criterion for dwell fatigue crack initiation in polycrystalline alloy Ti-6242 is proposed in this paper. Local stress peaks due to load shedding from time dependent plastic deformation fields in neighboring grains are held responsible for crack initiation in dwell fatigue. An accurately calibrated and experimentally validated crystal plasticity finite element (FE) model is employed for predicting slip system level stresses and strains. Vital microstructural features related to the grain morphology and crystallographic orientations are accounted for in the FE model by construction of microstructures that are statistically equivalent to those observed in orientation imaging microscopy scans. The output of the finite element method model is used to evaluate the crack initiation condition in the postprocessing stage. The functional form of the criterion is motivated from the similarities in the stress fields and crack evolution criteria ahead of a crack tip and dislocation pileup. The criterion is calibrated and validated by using experimental data obtained from ultrasonic crack monitoring techniques. It is then used to predict the variation in dwell fatigue lifetime for critical microstructural conditions. The studies are extended to field experiments on β forged Ti-6242. Macroscopic aspects of loading are explored for their effect on dwell fatigue life of Ti-6242.
Multiple Contacts of Similar Elastic Materials
Authors: Sundaram N. , Farris T. N.
Published: March 2009

The contact problem for an elastic body indenting a similar half-space resulting in multiple contacts is important for various applications. In this paper an exact fast numerical method based on singular integral equations is developed to solve the normal contact (including applied moments), partial slip, and shear-reversal problems for such contacts. The contact patches are considered to be fully interacting, with no simplifying assumptions. A contact algorithm to automatically generate trial values based on an analysis of the profile and to subsequently guide the solver toward convergence is detailed. Some applications are discussed, including regular rough cylinders and a regularly rough flat punch with rounded edges. The examples involve between 3 and 29 contacts. The partial slip problems include demonstration of cases with multiple stick zones in some contact patches and complete sliding in others.
Spatially Resolved Measuring Technique for Solid Oxide Fuel Cells
Authors: Metzger Patrick , Friedrich K. Andreas , Schiller Günter , Willich Caroline
Published: March 2009

In order to optimize solid oxide fuel cells for operation in highly efficient systems, a new measuring system with segmented cells has been developed, which allows us to determine local effects and to identify critical operating parameters during operation. The setup of the measuring system and experimental results for two examples—influence of hydrogen content and fuel utilization on performance and influence of load on power density and fuel utilization at operation with gasoline reformate as fuel—are presented to demonstrate the potential of the spatially resolved measuring technique.
Generic Real-Time Modeling of Solid Oxide Fuel Cell Hybrid Systems
Authors: Ghigliazza Francesco , Traverso Alberto , Massardo Aristide F. , Wingate John , Ferrari Mario
Published: March 2009

Real-time (RT) modeling is a recognized approach to monitor advanced systems and to improve control capabilities. Applications of RT models are commonly used in the automotive and aerospace fields. Starting from existing components and models developed in TRANSEO[REF], a new approach, called the multipurpose RT approach, is developed for the solid oxide fuel cell hybrid system application. Original C-based models have been reprogrammed into embedded MATLAB functions for direct use within MATLAB-SIMULINK. Also, models in TRANSEO have been simplified to improve execution time. Using MATLAB’s Real-Time Workshop application, the system model is able to be translated into an autogenerated C-code, and run as an application specific RT executable.
All-Perovskite Solid Oxide Fuel Cells, Synthesis and Characterization
Authors: Mohammadi Alidad , Wu Tsung-han , Smirnova Alevtina L. , Pusz Jakub , Sammes Nigel M.
Published: March 2009

Strontium- and magnesium-doped lanthanum gallate (LSGM) has been considered as a promising electrolyte for solid oxide fuel cell (SOFC) systems in recent years. In this work synthesis, electrochemical properties, phase evolution, and microstructure of an all-perovskite electrolyte-supported SOFC based on La0.75Sr0.25Cr0.5Mn0.5O3 (LSCM) porous anode, La0.8Sr0.2Ga0.7Mg0.3O2.8 (LSGM-2030) electrolyte, and La0.8Sr0.2MnO3 cathode at intermediate temperatures are studied. The phase evolution of synthesized LSGM and LSCM powders has been investigated, and it validates that there is no reaction between LSGM and LSCM at sintering temperature. The characterization study of the synthesized LSGM also indicates that sintering at 1500°C gives higher electrical conductivity compared with the currently published results, while for the pellets sintered at 1400°C and 1450°C the conductivity would be slightly lower. The effects of the firing temperature on the bulk and grain boundary resistivities are also discussed.
Development of Micro- to Macropores in Conductive Polymer-Based Gas Diffusion Layers for Proton Exchange Membrane Fuel Cells
Authors: Deyrail Yves , Mighri Frej , Kaliaguine Serge
Published: March 2009

The aim of this work is to improve the porosity of gas diffusion layers (GDLs) for proton exchange membrane fuel cell electrodes. These GDLs are made by twin-screw extrusion process from conductive formulations composed of polyamide11 (PA11)/polystyrene (PS) as the polymer matrix phase and an appropriate mixture of carbon black (CB) and graphite (GR) as the conductive additives. Final GDL porosity, especially macroporosity, was generated by selective extraction of the PS phase using adequate solvents. Since the generation of pores was found to be directly related to blend morphology, several blend compositions were studied and small amounts (2–6 wt %) of montmorillonite (MMT) clay were used as compatibilizer to improve the dispersion of the PS phase inside the PA11. It was observed that, although GDL volume porosity was not or slightly affected by the addition of MMT compatibilizer, its pore specific surface area was clearly increased. For GDLs made from a blend composed of 65 wt % of PA11/PS (30/70) and 35 wt % of GB/GR (57/43), an increase from 53 m2/g (with no MMT) to around 75 m2/g (with 2 wt % MMT) was obtained. This improvement within the addition of MMT was attributed to the modification of the dispersion state of PS phase. Such modification led to a higher connectivity of pores and consequently more accessibility to the micro/mesopores of CB and GR. The major changes observed with the incorporation of MMT compatibilizer were obtained for the small pore sizes (in the range of 10–400 nm). Depending on MMT content, a considerable shift of pore size distribution in this range to smaller or higher values was obtained. Then the MMT compatibilization could be considered as an interesting route to tailor GDL porous properties.
An Adhesion Model for Elastic-Contacting Fractal Surfaces in the Presence of Meniscus
Authors: Peng Y. F. , Guo Y. B. , Hong Y. Q.
Published: March 2009

The strong stiction of adjacent surfaces with meniscus is a major design concern in the devices with a microsized interface. The present research concerns the elastic adhesion of rough fractal surfaces in the presence of a thin liquid film. A rough fractal surface is characterized with a two-variable Weierstrass–Mandelbrot fractal function. The microcontact model of the single asperity is established in terms of the fractal parameters. The adhesion model from meniscus is developed with the Dugdale approximation of the Laplace pressure to consider the adhesive interaction within/outside the contact area. Then the Maugis–Dugdale model and its extension are used to solve the elastic adhesive interaction for the two approaching fractal surfaces by incorporating the fractal surface model. Simulations of the external force versus the interface stiffness, surface roughness, and relative humidity are performed, respectively. The simulation results show that the interface stiffness, surface topography, and relative humidity can heavily influence the interface adhesion of rough surfaces with meniscus.
Oil Churning Power Losses of a Gear Pair: Experiments and Model Validation
Authors: Seetharaman S. , Kahraman A. , Moorhead M. D. , Petry-Johnson T. T.
Published: March 2009

This paper presents the results of an experimental study on load-independent (spin) power losses of spur gear pairs operating under dip-lubricated conditions. The experiments were performed over a wide range of operating speed, temperature, oil levels, and key gear design parameters to quantify their influence on spin power losses. The measurements indicate that the static oil level, rotational speed, and face width of gears have a significant impact on spin power losses compared with other parameters such as oil temperature, gear module, and the direction of gear rotation. A physics-based gear pair spin power loss formulation that was proposed in a companion paper (Seetharaman and Kahraman, 2009, “Load-Independent Spin Power Losses of a Spur Gear Pair: Model Formulation,” ASME J. Tribol., 131, p. 022201) was used to simulate these experiments. Direct comparisons between the model predictions and measurements are provided at the end to demonstrate that the model is capable of predicting the measured spin power loss values as well as the measured parameter sensitivities reasonably well.
A Multilevel Model for Elastic-Plastic Contact Between a Sphere and a Flat Rough Surface
Authors: Wang F. Steven , Block Joseph M. , Chen W. Wayne , Martini Ashlie , Zhou Kun , Keer Leon M. , Wang Q. Jane
Published: March 2009

Elastic-plastic contact of a smooth sphere and a half-space with a real machined surface is simulated using an integration-based multilevel contact model. The total surface deflection is composed of bulk and asperity deformations. They are calculated at the global and the asperity level, respectively, which are connected through the asperity-supporting load. With this new model, the accurate contact area and contact pressure under a given load are quickly predicted using a relatively coarse grid system. The calculated load-area curve shows good agreement with the experimental data. Finally, the effects of the surface topography, including roughness and the asperity radius, upon the real contact area are analyzed.
Multicoating Inhomogeneities Problem for Effective Viscoelastic Properties of Particulate Composite Materials
Authors: Koutsawa Yao , Cherkaoui Mohammed , Daya El Mostafa
Published: March 2009

The present work extends the multicoated micromechanical model of Lipinski et al. (2006, “Micromechanical Modeling of an Arbitrary Ellipsoidal Multi-Coated Inclusion,” Philos. Mag., 86(10), pp. 1305–1326) in the quasistatic domain to compute the effective material moduli of a viscoelastic material containing multicoated spherical inclusions displaying elastic or viscoelastic behavior. Losses are taken into account by introducing the frequency-dependent complex stiffness tensors of the viscoelastic matrix and the multicoated inclusions. The advantage of the micromechanical model is that it is applicable to the case of nonspherical multicoated inclusions embedded in anisotropic materials. The numerical simulations indicate that with proper choice of material properties, it is possible to engineer multiphase polymer system to have a high-loss modulus (good energy dissipation characteristics) for a wide range of frequencies without substantially degrading the stiffness of the composite (storage modulus). The numerical analyses show also that with respect to the relative magnitudes of the loss factors and the storage moduli of the matrix, inclusion and coating, the overall properties of the viscoelastic particulate composite are dominated by the properties of the matrices in some frequency ranges. The model can thus be a suitable tool to explore a wide range of microstructures for the design of materials with high capacity to absorb acoustic and vibrational energies.
Biped RCCR Mechanism
Authors: Chao Liu , Yan-An Yao
Published: March 2009

An untraditional application of the four-link RCCR (two revolute and two cylindric joints) mechanism is presented in this paper and is used as a novel biped walking mechanism. By taking advantage of the singular configuration of the mechanism, two actuators are employed to realize planar movements. Kinematic analysis, gait planning, and stability analysis are performed, and a prototype is developed and tested.
PRINCIPAL BUNDLES ON RATIONALLY CONNECTED FIBRATIONS OVER ABELIAN VARIETIES
Authors: BISWAS INDRANIL
Published: March 2009

Let f : M → A be a smooth surjective algebraic morphism, where M is a connected complex projective manifold and A a complex abelian variety, such that all the fibers of f are rationally connected. We show that an algebraic principal G-bundle EG over M admits a flat holomorphic connection if EG admits a holomorphic connection; here G is any connected reductive linear algebraic group defined over ℂ. We also show that EG admits a holomorphic connection if and only if any of the following three statements holds.

(1) The principal G-bundle EG is semistable, c2( ad (EG)) = 0, and all the line bundles associated to EG for the characters of G have vanishing rational first Chern class.

(2) There is an algebraic principal G-bundle E'G on A such that f*E'G = EG, and all the translations of E'G by elements of A are isomorphic to E'G itself.

(3) There is a finite étale Galois cover [Formula: see text] and a reduction of structure group [Formula: see text] to a Borel subgroup B ⊂ G such that all the line bundles associated to ÊB for the characters of B have vanishing rational first Chern class.

In particular, the above three statements are equivalent.
AN ULTRA-LOW-POWER CURRENT-MODE INTEGRATED CMOS INSTRUMENTATION AMPLIFIER FOR PERSONAL ECG RECORDERS
Authors: BAGHINI MARYAM SHOJAEI , NAG SUDIP , LAL RAKESH K. , SHARMA DINESH K.
Published: March 2009

This paper presents an ultra-low-power current-mode ECG instrumentation amplifier, which is designed based on the current balancing technique and fabricated in TSMC 0.35 μm CMOS process. The instrumentation amplifier, which is presented here has three features. First, the instrumentation amplifier is a full-CMOS implementation of current-balancing technique applied for ECG signal conditioning. Second, the instrumentation amplifier is of ultra-low-power due to a power-oriented design methodology, which makes its power consumption very low compared to the earlier reported works for ECG recording applications. Third, integrated programmable bandpass filtering is implemented in the amplifier itself, which provides a compact solution for analog ECG signal conditioning. Measurement results show that the amplifier only draws 9 μA current from a 3.3 V lithium-ion battery, while CMRR of 100 dB and input voltage dynamic range of ± 6 mV are achieved. By considering trade-offs between input noise voltage and power, noise performance was compromised with power and area for ultra-low-power ECG signal conditioning applications. Measurement results show [Formula: see text] input referred noise voltage with a flicker noise corner frequency of 15 Hz at 9 μA dc current and small area, which is appropriate for the desired application. Measurement results meet the recommended specifications for signal conditioning of portable ECG monitoring devices. Design methodology, fabrication considerations, measurement setup, and experimental results are also explained in this paper.
ADAPTIVE DELAY CORRECTION FOR RUNTIME VARIATION IN DYNAMIC VOLTAGE SCALING SYSTEMS
Authors: WOLPERT DAVID , AMPADU PAUL
Published: March 2009

Temperature and voltage fluctuations affect delay sensitivity differently, as supply voltage is reduced. These differences make runtime variations particularly difficult to manage in dynamic voltage scaling systems, which adjust supply voltage in accordance with the required operating frequency. To include process variation in current table-lookup methods, a worst-case process is typically assumed. We propose a new method that takes process variation into account and reduces the excessive runtime variation guardbands. Our approach uses a ring oscillator to generate baseline frequencies, and employs a guardband lookup table to offset this baseline. The new method ensures robust operation and reduces power consumption by up to 20% compared with a method that assumes worst-case process variation in filling a lookup table.
A ZERO-CURRENT SWITCHING PWM FLYBACK CONVERTER WITH LOW CURRENT STRESS
Authors: YEUNG Y. P. BENNY , IU H. H. C.
Published: March 2009

An actively current clamped zero-current switching (ZCS) flyback converter is proposed in this paper. ZCS condition is obtained for all transistors for reducing switching loss and electromagnetic interference. With the current clamping technique, current stress of the converter is low. Output voltage of this converter can be controlled with fixed frequency. Electrical isolation is provided. Operation principles are discussed in the paper. Mathematical descriptions and computer simulation verification are provided.
APPROXIMATION OF FELLER PROCESSES BY MARKOV CHAINS WITH LÉVY INCREMENTS
Authors: BÖTTCHER BJÖRN , SCHILLING RENÉ L.
Published: March 2009

We consider Feller processes whose generators have the test functions as an operator core. In this case, the generator is a pseudo differential operator with negative definite symbol q(x, ξ). If |q(x, ξ)| < c(1 + |ξ|2), the corresponding Feller process can be approximated by Markov chains whose steps are increments of Lévy processes.

This approximation can easily be used for a simulation of the sample path of a Feller process.

Further, we provide conditions in terms of the symbol for the transition operators of the Markov chains to be Feller. This gives rise to a sequence of Feller processes approximating the given Feller process.
RETURN TIME STATISTICS OF INVARIANT MEASURES FOR INTERVAL MAPS WITH POSITIVE LYAPUNOV EXPONENT
Authors: BRUIN HENK , TODD MIKE
Published: March 2009

We prove that multimodal maps with an absolutely continuous invariant measure have exponential return time statistics around almost every point. We also show a "polynomial Gibbs property" for these systems, and that the convergence to the entropy in the Ornstein–Weiss formula has normal fluctuations. These results are also proved for equilibrium states of some Hölder potentials.
EXISTENCE CRITERIA FOR SOLUTIONS OF LINEAR STOCHASTIC DIFFERENTIAL EQUATIONS WITH SKEW-SYMMETRIC DIFFERENTIAL OPERATOR AND ADDITIVE FRACTIONAL BROWNIAN NOISE
Authors: BELINSKIY BORIS P. , CAITHAMER PETER
Published: March 2009

We consider a Hilbert-valued linear stochastic differential equation driven by fractional Gaussian noise. We give criteria for weak and strong solutions to exist in terms of the differential operator, which we assume to be skew-symmetric, and the covariance operator of the noise. We consider a class of PDE as examples. We show that the energy of these systems is finite if and only if a weak solution to the associated ODE exists. We also relate these conditions to conditions obtained by previous authors.
THEORETICAL STUDY ON THE SELF-REACTION MECHANISM OF CH2ClO2 RADICALS
Authors: WEI WEN-MEI , ZHENG REN-HUI , TIAN YAN , GU ZHI-HONG , XIE YONG-YAN
Published: March 2009

The complex potential energy surface for the self-reaction of CH 2 ClO 2 radicals, including 12 intermediates, 33 interconversion transition states, and 21 major dissociation products, was theoretically probed at the CCSD(T)/cc-pVDZ//B3LYP/6-311G(2d,2p) level of theory. The geometries and relative energies for various stationary points were determined. Based on the calculated CCSD(T)/cc-pVDZ potential energy surface, the possible mechanism for the studied system was proposed. It is shown that the most feasible channels are those leading to 22 CH 2 ClO + 3 O 2, 2 CH 2 ClO + 2 HO 2 + CHClO , 2 CH 2 ClO + HCl + 2 CH(O)O 2, 2 CH 2 ClO + 3 O 2 + 2 Cl + CH 2 O , and p,s,o- CH 2 ClOOOCl + CH 2 O with the energy barriers of 5.6, 11.8, 12.4, 12.4, and 13.5 kcal/mol, respectively. Their mechanisms are that CH 2 ClO 2 and CH 2 ClO 2 form a tetroxide intermediate first, then the intermediate dissociates to yield the productions or through multi-steps reactions to produce the final products.
3D-QSAR STUDIES OF SUBSTITUTED 4-ARYL/HETEROARYL-4H-CHROMENES AS APOPTOSIS INDUCERS USINGCoMFAANDCoMSIA
Authors: LIAO SI YAN , QIAN LI , MIAO TI FANG , SHEN YONG , ZHENG KANG CHENG
Published: March 2009

Three-dimensional (3D) quantitative structure–activity relationships (QSARs) of 36 apoptosis inducers, substituted 4-aryl/heteroaryl-4H-chromenes with anticancer activity against human breast cancer cell lines T47D, have been studied by using methods of comparative molecular field analysis (CoMFA) and comparative molecular similarity analysis (CoMSIA). The established 3D-QSAR models in training set show not only significant statistical quality, but also predictive ability, with high correlation coefficient (R2) values and cross-validation coefficient (q2) values: CoMFA (R2, q2: 0.944, 0.747), CoMSIA (R2, q2: 0.944, 0.704). Moreover, the predictive abilities of the CoMFA and CoMSIA models were further confirmed by a test set, giving the predictive correlation coefficients ([Formula: see text] values) of 0.845 and 0.851, respectively. Based on the CoMFA and CoMSIA contour map analyses, some key factors responsible for anticancer activity of this series of compounds have been found as follows: the steric interaction plays a decisive role in determining the anticancer activities of these compounds; bulky groups as substituent R1are not tolerated; in addition to a steric moderation, higher degree of electropositivity and hydrophobicity on the terminal alkyl of substituent R2might be favorable to the activity; the substituent R3should be hydrophobic; bulky and strong electron withdrawing groups for the substituent R4are not advantageous to the activity; simultaneously introducing large electronegative atoms as hydrogen-acceptors to the first atoms of the substituents R5and R6may increase the activity, but substituents R5and R6with a linking group – OCH2O – may decrease the activity. Such results can offer some useful theoretical references for understanding the action mechanism, designing more potent derivatives, and predicting their activities prior to synthesis.
CHARACTERISING INDICATORS OF SUSTAINABLE LAND MANAGEMENT IN INDIAN HIMALAYAN SLOPING LANDS
Authors: RAIS M. , SHARMA D. C.
Published: March 2009

Viewing environmental perspectives and growing concerns related to ecological balance in nature together with social, agricultural, industrial and economic developments, sustainable development of ecosystems has become a crucial issue with a particularity to hill and mountain regions around the world. Out of a vast coverage on sustainable development, SLM (Sustainable Land Management) is one important ecosystem module that itself has a wider expansion and is construed of several folds and dimensions which have been standardised well by an international working group consisted of Agriculture Canada, IBSRAM (now merged with IWMI), FAO, TROPSOIL, USDA-SCS, IFDC and others in the form of a standardised guideline, i.e., FESLM (Framework for Evaluating Sustainable Land Management). In view of a comprehensive account on SLM, indicators of sustainability of land management have been characterised on the basis of five pillars viz. productivity, security, protection, economic viability and acceptability in the hill areas covering a long stretch of western, eastern and entire north-eastern Himalayas encompassing the states of J&K, Himachal Pradesh, Uttaranchal, Assam Sikkim, Arunachal Pradesh, Meghalaya, Manipur etc. in the present study. Various parameters have been chosen to carve out indicators satisfying each basic five pillar of the FESLM standard. Also, the efficacy of these indicators has been observed on some of the important agricultural systems being used in practice in different sloping lands in India; thus, it has been concluded that the sustainability needs to be enhanced in north-eastern Himalayan farming systems.
REVIEW AND DEVELOPMENT OF ENVIRONMENTAL IMPACT STATEMENTS IN KUWAIT: A STEP TOWARDS MITIGATION OF ENVIRONMENTAL CRISIS ASSOCIATED WITH MAJOR PROJECTS
Authors: MOHAMED AL-DAMKHI ALI , ABDUL-WAHAB SABAH AHMED
Published: March 2009

Major development projects, within the third review of the Kuwait Master Plan (KMP3), are proposed for the period (2005–2030). These projects include, among other things, the construction of new towns, industrial areas, power plants, highways, hospitals, waterfront projects and sanitary projects. All of these projects are well known to have adverse environmental impacts unless necessary precautions are taken in their planning stages. As per Article 8 of Law 21 of 1995 and its amendments, the proponents of such projects are requested to submit a comprehensive Environmental Impact Statement (EIS) document for review before an environmental permit is given by the Environment Public Authority (EPA) in Kuwait. There is at present inadequate information available to help the proponents in this task, and the aim of this paper, is to provide a set of preliminary guidelines for the review and development of EIS documents for various types of major development projects. Although the examples focus on Kuwait, the principles discussed are generally applicable. The future challenges to enhance the review and development process are also discussed.
EXAMINING QUALITY OF ENVIRONMENTAL OBJECTIVES, TARGETS AND INDICATORS IN ENVIRONMENTAL REPORTS PREPARED FOR STRATEGIC ENVIRONMENTAL ASSESSMENT
Authors: DONNELLY ALISON , PRENDERGAST TERRY , HANUSCH MARIE
Published: March 2009

Due to the pivotal role of environmental objectives, targets and indicators in Strategic Environmental Assessment (SEA) to assess environmental impact and monitor environmental condition resulting from a proposed plan it is crucial to ensure high quality in their development. Here we present a quality assurance checklist for practitioners to ensure compliance with (i) the minimum requirements of the SEA Directive and (ii) guidelines established by the Irish government for SEA of land use development plans. Furthermore, we propose additional recommended tasks based on expertise and experience gained in carrying out SEA to ensure high quality. Some of the questions posed in the checklist include, for example, "Are the environmental indicators capable of demonstrating the likely significant environmental impact(s) of the implementation of the proposed plan or programme?", "Have limits and thresholds been established for each environmental target?" and "Is responsibility for implementing the monitoring programme clearly defined?". We applied the completed checklist to 10 environmental reports from Ireland, Wales, England, Malta and Germany and proposed a grading system for comparative purposes. The results showed varying quality among the ERs from Ireland, UK and Malta. In addition, we found that the checklist did not directly apply to the German ERs because of the different approach taken to SEA whereby environmental targets and indicators were used in a more implicit manner than elsewhere. However, as environmental objectives and the monitoring programmes were similar for all ERs we concluded that different approaches still resulted in a manageable and focused monitoring system.
HL-1 mouse cardiomyocyte injury and death after simulated ischemia and reperfusion: roles of pH, Ca2+-independent phospholipase A2, and Na+/H+ exchange
Authors: Andersen Ann-Dorit , Poulsen Kristian Arild , Lambert Ian H. , Pedersen Stine Falsig
Published: March 2009

The Ca2+-independent phospholipase A2 VI (iPLA2-VI) and the Na+/H+ exchanger isoform 1 (NHE1) are highly pH-sensitive proteins that exert both protective and detrimental effects in cardiac ischemia-reperfusion. Here, we investigated the role of extracellular pH (pHo) in ischemia-reperfusion injury and death and in regulation and function of iPLA2-VI and NHE1 under these conditions. HL-1 cardiomyocytes were exposed to simulated ischemia (SI; 0.5% O2, 8 mM K+, and 20 mM lactate) at pHo 6.0 and 7.4, with or without 4 or 8 h of reperfusion (SI/R). Cytochrome c release and caspase-3 activation were reduced after acidic compared with neutral SI, whereas necrotic death, estimated as glucose-6-phosphate dehydrogenase release, was similar in the two conditions. Inhibition of iPLA2-VI activity by bromoenol lactone (BEL) elicited cardiomyocyte necrosis during normoxia and after acidic, yet not after neutral, SI. The isoform-selective enantiomers R- and S-BEL both mimicked the effect of racemic BEL after acidic SI. In contrast, inhibition of NHE activity by EIPA had no significant effect on necrosis after SI. Both neutral and acidic SI were associated with a reversible loss of F-actin and cortactin integrity. Inhibition of iPLA2-VI disrupted F-actin, cortactin, and mitochondrial integrity, whereas inhibition of NHE slightly reduced stress fiber content. iPLA2-VIA and NHE1 mRNA levels were reduced during SI and upregulated in a pHo-dependent manner during SI/R. This also affected the subcellular localization of iPLA2-VIA. Thus, the mode of cell death and the roles and regulation of iPLA2-VI and NHE1 are at least in part determined by the pHo during SI. In addition to having clinically relevant implications, these findings can in part explain the contradictory results obtained from previous studies of iPLA2-VIA and NHE1 during cardiac I/R.
Dynamic interactions between L-type voltage-sensitive calcium channel Cav1.2 subunits and ahnak in osteoblastic cells
Authors: Shao Ying , Czymmek Kirk J. , Jones Patricia A. , Fomin Victor P. , Akanbi Kamil , Duncan Randall L. , Farach-Carson Mary C.
Published: March 2009

Voltage-sensitive Ca2+ channels (VSCCs) mediate Ca2+ permeability in osteoblasts. Association between VSCC α1- and β-subunits targets channel complexes to the plasma membrane and modulates function. In mechanosensitive tissues, a 700-kDa ahnak protein anchors VSCCs to the actin cytoskeleton via the β2-subunit of the L-type Cav1.2 (α1C) VSCC complex. Cav1.2 is the major α1-subunit in osteoblasts, but the cytoskeletal complex and subunit composition are unknown. Among the four β-subtypes, the β2-subunit and, to a lesser extent, the β3-subunit coimmunoprecipitated with the Cav1.2 subunit in MC3T3-E1 preosteoblasts. Fluorescence resonance energy transfer revealed a complex between Cav1.2 and β2-subunits and demonstrated their association in the plasma membrane and secretory pathway. Western blot and immunohistochemistry showed ahnak association with the channel complex in the plasma membrane via the β2-subunit. Cytochalasin D exposure disrupted the actin cytoskeleton but did not disassemble or disrupt the function of the complex of L-type VSCC Cav1.2 and β2-subunits and ahnak. Similarly, small interfering RNA knockdown of ahnak did not disrupt the actin cytoskeleton but significantly impaired Ca2+ influx. Collectively, we showed that Cav1.2 and β2-subunits and ahnak form a stable complex in osteoblastic cells that permits Ca2+ signaling independently of association with the actin cytoskeleton.
Inhibitory effects of polyunsaturated fatty acids on Kv4/KChIP potassium channels
Authors: Boland Linda M. , Drzewiecki Michelle M. , Timoney Gabriela , Casey Erin
Published: March 2009

Kv4/K channel interacting protein (KChIP) potassium channels are a major class of rapidly inactivating K+channels in neurons and cardiac muscle. Modulation of Kv4/KChIP channels by polyunsaturated fatty acids (PUFAs) is important in the regulation of cellular excitability and the induction of activity-dependent synaptic plasticity. Using the Xenopus laevis oocyte expression system, we studied the inhibition by PUFAs of the peak outward K+current and the accompanying increase in the rate of current inactivation of rKv4.2/rKChIP1b. Inhibitory effects do not depend on KChIP coexpression since Kv4.2 channels lacking an NH2-terminal KChIP association region were substantially inhibited by PUFAs and showed strong kinetic modulation. PUFAs accelerated both the fast and slow time constants that describe the kinetics of Kv4/KChIP inactivation. The time course of entry into closed inactivated states was facilitated by PUFAs, but steady-state inactivation and recovery from inactivation were unaltered. PUFA inhibition of Kv4/KChIP current was not use dependent. The concentration-response relationship for arachidonic acid (AA) inhibition of Kv4/KChIP channels mimicked that for activation of TRAAK channels. Internal serum albumin largely prevents the inhibitory effects of externally applied AA, and the membrane-impermeant AA-CoA is inactive when applied externally. Overall, our data suggest that PUFAs inhibit Kv4/KChIP channels by facilitating inactivation from open and closed gating states and that access of the fatty acid to the internal leaflet of the membrane is important. These results improve our understanding of the mechanisms for the inhibitory effects of PUFAs on Kv4/KChIP channel function.
HFEC282Y Mutation as a Genetic Modifier Influencing Disease Susceptibility for Chronic Myeloproliferative Disease
Authors: Andrikovics Hajnalka , Meggyesi Nora , Szilvasi Aniko , Tamaska Julia , Halm Gabriella , Lueff Sandor , Nahajevszky Sarolta , Egyed Miklos , Varkonyi Judit , Mikala Gabor , Sipos Andrea , Kalasz Laszlo , Masszi Tamas , Tordai Attila
Published: March 2009

Iron metabolism has been implicated in carcinogenesis and several studies assessed the potential role of genetic variants of proteins involved in iron metabolism (HFE C282Y, TFR S142G) in different malignancies. Few reports addressed this issue with relation to chronic myeloproliferative disorders (CMPD). The aims of our study were (a) to examine the potential associations of CMPD development with genetic modifiers of iron metabolism in a large cohort of CMPD patients; (b) to examine associations of genetic variants of proteins involved in iron metabolism; and acquired JAK2 V617F mutation with clinical characteristics of CMPD. HFE C282Y was genotyped in 328 CMPD patients and 996 blood donors as controls, HFE H63D, and TFR S142G were tested in CMPD patients and 171 first time blood donors. JAK2 V617F mutation was tested in CMPD patients and in 122 repeated blood donors. Decreased C282Y allele frequency (allele frequency ± 95% confidence interval) was found in the CMPD group (1.8% ± 1.0%) compared with controls (3.4% ± 0.8%; P = 0.048). TFR S142G allele frequency was reduced among V617F-negative CMPD patients (34.8% ±7.6%) compared with controls (47.8% ± 5.4%; P = 0.02). The frequency of JAK2 V617F was 75.9% (249 of 328) in the CMPD group. At presentation, elevated hemoglobin levels were found in V617F-positive patients compared with V617F-negative counterparts (P < 0.000). Vascular complications (26.6% versus 15.2%; P = 0.039) as well as female gender (57.4% versus 41.8%; P = 0.019) were more common in V617F-positive patients. We found that HFE C282Y might be associated with a protective role against CMPD. Because chronic iron deficiency or latent anemia may trigger disease susceptibility for CMPD, HFE C282Y positivity may be a genetic factor influencing this effect. (Cancer Epidemiol Biomarkers Prev 2009;18(3):929–34)
CD38Gene Polymorphisms Contribute to Genetic Susceptibility to B-Cell Chronic Lymphocytic Leukemia: Evidence from Two Case-Control Studies in Polish Caucasians
Authors: Jamroziak Krzysztof , Szemraj Zofia , Grzybowska-Izydorczyk Olga , Szemraj Janusz , Bieniasz Magdalena , Cebula Barbara , Giannopoulos Krzysztof , Balcerczak Ewa , Jesionek-Kupnicka Dorota , Kowal Malgorzata , Kostyra Aleksandra , Calbecka Malgorzata , Wawrzyniak Ewa , Mirowski Marek , Kordek Radzislaw , Robak Tadeusz
Published: March 2009

Given the recent findings on the importance of CD38 signaling in the pathogenesis of B-cell chronic lymphocytic leukemia (B-CLL), we hypothesized that single nucleotide polymorphisms (SNP) in the CD38 gene may be related to B-CLL risk. We evaluated two potentially functional CD38 SNPs, intronic rs6449182 (184C>G) and missense rs1800561 (418C>T, Arg140Trp) in two hospital-based case-control studies (study A and validation study B). Genotyping was done using PCR-based assays in a total of 460 Polish Caucasian patients with B-CLL and 503 age-matched and gender-matched controls. We found that frequencies of both variant alleles (rs6449182 G and rs1800561 T) were significantly higher in B-CLL. In study A, logistic regression analysis revealed an association between B-CLL and genotypes: rs6449182 CG [odds ratio (OR), 3.57; 95% confidence interval (95% CI), 2.4-5.3], rs6449182 GG (OR, 5.2; 95% CI, 2.36-11.5), and rs1800561 CT (OR, 6.72; 95% CI, 1.5-30.1), although no homozygous rs1800561 TT genotype was detected in either study. These results were confirmed in study B, which showed an association between B-CLL and genotypes rs6449182 CG (OR, 4.00; 95% CI, 2.7-6.0), rs6449182 GG (OR, 12.84; 95% CI, 4.3-38.7), and rs1800561 CT (OR, 10.12; 95% CI, 1.3-81.6), and in the combined analysis of both studies. We also observed that rs6449182 G carriers had more advanced clinical stage (P = 0.002) and tended to be younger at diagnosis (P = 0.056). Furthermore, we found higher CD38 transcript levels and higher proportions of CD38-positive cells in carriers of rs6449182 G and rs1800561 T alleles (P < 0.05 for all comparisons). In conclusion, our data show that CD38 SNPs may affect CD38 expression and contribute to the increased risk of B-CLL carcinogenesis. (Cancer Epidemiol Biomarkers Prev 2009;18(3):945–53)
Socioeconomic Inequalities in Cancer Survival in New Zealand: The Role of Extent of Disease at Diagnosis
Authors: Jeffreys Mona , Sarfati Diana , Stevanovic Vladimir , Tobias Martin , Lewis Chris , Pearce Neil , Blakely Tony
Published: March 2009

We examined socioeconomic inequalities in cancer survival in New Zealand among 132,006 people ages 15 to 99 years who had a cancer registered (1994-2003) and were followed up to 2004. Relative survival rates (RSR) were calculated using deprivation-specific life tables. A census-based measure of socioeconomic position (New Zealand deprivation based on the 1996 census) based on residence at the time of cancer registration was used. All RSRs were age-standardized, and further standardization was used to investigate the effect of extent of disease at diagnosis on survival. Weighted linear regression was used to estimate the deprivation gap (slope index of inequality) between the most and least deprived cases. Socioeconomic inequalities in cancer survival were evident for all of the major cancer sites, with the deprivation gap being particularly high for prostate (−0.15), kidney and uterus (both −0.14), bladder (−0.12), colorectum (−0.10), and brain (+0.10). Accounting for extent of disease explained some of the inequalities in survival from breast and colorectal cancer and melanoma and all of the deprivation gaps in survival of cervical cancer; however, it did not affect RSRs for cancers of the kidney, uterus, and brain. No substantial differences between the total compared with the non-Māori population were found, indicating that the findings were not due to confounding by ethnicity. In summary, socioeconomic disparities in survival were consistent for nearly all cancer sites, persisted in ethnic-specific analyses, and were only partially explained by differential extent of disease at diagnosis. Further investigation of reasons for persisting inequalities is required. (Cancer Epidemiol Biomarkers Prev 2009;18(3):915–21)
Progressive Commercial Cigarette Yield Reduction: Biochemical Exposure and Behavioral Assessment
Authors: Benowitz Neal L. , Dains Katherine M. , Hall Sharon M. , Stewart Susan , Wilson Margaret , Dempsey Delia , Jacob Peyton
Published: March 2009

Background: Mandated reduction of exposure to nicotine and other cigarette toxins has been proposed as a possible national regulatory strategy. However, tapering using lower yield commercial cigarettes may not be effective in reducing nicotine or tar exposure due to compensatory smoking behavior. We examined the effects of gradual reduction of nicotine yield in commercial cigarettes on smoking behavior, with an assessment of nicotine intake and exposure to tobacco smoke toxins.

Methods: This 10-week longitudinal study of 20 smokers involved smoking the usual brand followed by different brands with progressively lower machine-determined yields, ranging from 0.9 to 0.1 mg nicotine, each smoked for 1 week. Subjects were followed for 4 weeks after returning to smoking the usual brand (or quitting). Smoking behaviors, biomarkers of tobacco smoke exposure, and cardiovascular effects were measured.

Findings: Cotinine and other biomarkers of smoke exposure remained unchanged comparing the usual brand with the 0.4 mg nicotine brands. A 30% to 40% decrease in nicotine, carbon monoxide, and carcinogen exposure comparing 0.1 mg nicotine cigarettes with baseline was observed. Self-efficacy was significantly increased and dependence decreased after tapering.

Implications: We confirm prior cross-sectional population and experimental studies showing complete compensation for cigarettes down to the 0.4 mg nicotine range. Nicotine and tobacco toxin exposure were substantially reduced while smoking 0.1 mg nicotine cigarettes. Our data suggest that the degree of nicotine dependence of smokers may be lowered with progressive yield tapering. Gradual tapering of smokers from regular to ultralow nicotine yield commercial cigarettes might facilitate smoking cessation and warrants future research. (Cancer Epidemiol Biomarkers Prev 2009;18(3):876–83)
Yield of Claims Data and Surveys for Determining Colon Cancer Screening among Health Plan Members
Authors: Pignone Michael , Scott Tracy L. , Schild Laura A. , Lewis Carmen , Vázquez Raquel , Glanz Karen
Published: March 2009

Screening can reduce incidence and mortality from colorectal cancer but has been underutilized. Efforts to increase screening depend on accurate data about screening status. We sought to evaluate the independent and combined yield of claims and direct survey for identifying colorectal cancer screening among average-risk health plan beneficiaries. Participants were Aetna members ages between 52 and 80 years from 32 primary care practices in Florida and Georgia participating in the Communicating Health Options through Information and Cancer Education study. Main outcomes were the proportion of average-risk patients who were up-to-date with colorectal cancer screening based on claims data and the estimated additional yield of survey data for patients with no evidence of screening in their claims history. Of 4,020 average-risk members identified, claims data indicated that 1,066 (27%) had recent colorectal cancer screening. Among the 1,269 average-risk members with no evidence of screening by claims data who returned surveys, 498 (39%) reported being up-to-date with screening. Combining claims data and survey data and accounting for survey nonresponse, we estimate that 47% to 59% of member patients were actually up-to-date with screening, an additional yield of 20 to 32 percentage points. We conclude that, among health plan members, the combination of claims data and survey information had substantially higher yield than claims data alone for identifying colorectal cancer screening. (Cancer Epidemiol Biomarkers Prev 2009;18(3):726–31)
Effect of Population Trends in Body Mass Index on Prostate Cancer Incidence and Mortality in the United States
Authors: Fesinmeyer Megan Dann , Gulati Roman , Zeliadt Steve , Weiss Noel , Kristal Alan R. , Etzioni Ruth
Published: March 2009

Concurrent with increasing prostate cancer incidence and declining prostate cancer mortality in the United States, the prevalence of obesity has been increasing steadily. Several studies have reported that obesity is associated with increased risk of high-grade prostate cancer and prostate cancer mortality, and it is thus likely that the increase in obesity has increased the burden of prostate cancer. In this study, we assess the potential effect of increasing obesity on prostate cancer incidence and mortality. We first estimate obesity-associated relative risks of low- and high-grade prostate cancer using data from the Prostate Cancer Prevention Trial. Then, using obesity prevalence data from the National Health and Nutrition Examination Survey and prostate cancer incidence data from the Surveillance, Epidemiology, and End Results program, we convert annual grade-specific prostate cancer incidence rates into incidence rates conditional on weight category. Next, we combine the conditional incidence rates with the 1980 prevalence rates for each weight category to project annual grade-specific incidence under 1980 obesity levels. We use a simulation model based on observed survival and mortality data to translate the effects of obesity trends on prostate cancer incidence into effects on disease-specific mortality. The predicted increase in obesity prevalence since 1980 increased high-grade prostate cancer incidence by 15.5% and prostate cancer mortality by between 7.0% (under identical survival for obese and nonobese cases) and 23.0% (under different survival for obese and nonobese cases) in 2002. We conclude that increasing obesity prevalence since 1980 has partially obscured declines in prostate cancer mortality. (Cancer Epidemiol Biomarkers Prev 2009;18(3):808–15)