bluuebunny/crossref_metadata_2025 huggingface dataset:
Justification for Onsite Transfer of Type B Packages After Extended Storage
Authors: Houghtaling T. Kurt , Skidmore T. Eric
Published: July 2008

This paper offers a practical means of qualifying previously loaded Type B packages for transportation onsite within the DOE complex after years of protected storage, while supporting the DOE program to maintain radworker dose as low as reasonable achievable (ALARA). Specifically, the paper discusses relevant packaging components and introduces part of a surveillance program carried out at the Savannah River Site supporting long-term storage of 3013-processed plutonium-bearing materials within closed 9975 packages and its application to DOE’s Equivalent Safety. Under normal service, maintenance is carried out annually to re-qualify the 9975 packagings for leak-tight transportation service. While in storage, however, annual maintenance was judged not to provide a significant increase in safety but to increase storage operation costs and to violate ALARA principles. Hence, a surveillance program was developed to investigate and confirm predictions of storage-related behavior for 9975 packaging materials, including the performance of O-ring seals and Celotex® insulation. The combination of analytical evaluations with surveillance data is shown sufficient to ensure that the 9975 packages can accommodate 1) time at storage temperature and 2) cumulative radiation dose without compromising subsequent performance under regulatory Normal Conditions of Transport or site-specific credible accident conditions.
Elastic-Plastic Limit Analysis for Perforated Plates With Triangular Array of Circular Holes
Authors: Duan Xinjian , Weck Arnaud , Wilkinson David S.
Published: July 2008

The plastic limit load design for a perforated structure that contains a large amount of circular holes has attracted much attention from power industry in recent years. Most of the previous analyses have been built on the elastic-perfectly plastic material model with small strain finite element formulation. In the present work, a series of newly developed heterogeneous unit cells based on large strain finite element formulation are applied to consider the effect of work hardening rate and the unit cell size on the computed limit load and failure modes. The results indicate that as the unit cell size increases, the unit cell tends to localize early. Also, we found that for the pre-work hardened materials with a strain-hardening coefficient of less than 0.1, work hardening rate has less effect on the computed limit load, but substantial impact on the calculated local strain magnitude.
Material Degradation in ACR-700 Fuel Channel Components
Authors: Shah V. N. , Natesan K. , Greene C. A.
Published: July 2008

The ACR (Advanced CANDU Reactor)-700 shares many design features with operating CANDU (CANada Deuterium Uranium) reactors, such as horizontal pressure tubes, heavy water moderator, and on-line fueling. However, there are some departures from the operating reactors that could affect the performance of structural materials. These include use of light water coolant, higher coolant pressure and temperature, enriched fuel rather than natural uranium, and higher fuel burnup. More important, the ACR-700 has many design features that set it apart from conventional and evolutionary light water reactors. This paper reviews the available literature related to design and structural materials for ACR-700 fuel channel components (Zr-2.5Nb pressure tubes, calandria tubes, annular spacers, and end fittings). The objectives were to identify the potential degradation mechanisms, evaluate the main degradation mechanism causing field failures, and analyze the available data to assess the performance of various components over the design/service life of the ACR-700. The review concludes that delayed hydride cracking (DHC) has been a primary degradation mechanism causing failure of CANDU pressure tubes. The influence of light water coolant environment on DHC initiation in the ACR 700 needs evaluation. The main concern is the potential for generation of hydrogen due to corrosion of the pressure tubes and its ingress into them, thereby making the tubes susceptible to DHC.
Buckling of Single-Deck Floating Roofs in Aboveground Oil Storage Tanks Due to Circumferential Bending Load
Authors: Yoshida Shoichi , Kitamura Kazuhiro
Published: July 2008

The 2003 Tokachi-Oki earthquake caused severe damage to oil storage tanks due to liquid sloshing. Six single-deck floating roofs had experienced structural problems as evidenced by sinking failure in large diameter tanks at the refinery at Tomakomai, Japan. The pontoon of floating roof might be buckled due to circumferential bending moment during the sloshing. The content in the tank was spilled on the floating roof from small failures which were caused in the rap welding joints of pontoon bottom plate by the buckling. Then the floating roof began to lose buoyancy and submerged into the content slowly. The failure of the roof expanded gradually in the sinking process. It is presumed that the initial small failures were caused by the elastic buckling of the pontoon due to circumferential bending moment. This paper presents the buckling strength of the pontoon using axisymmetric shell finite element analysis. Linear elastic bifurcation buckling analysis is carried out and the buckling characteristics of the pontoon are investigated. The result shows that the thickness of both pontoon roof and bottom plates have significantly affect the buckling strength.
Shakedown During Fatigue of Residual Stresses Introduced by Different Mechanical Surface Treatments
Authors: Gill Christopher M. , Withers Philip J. , Evans Alex , Fox Neil , Akita Koichi
Published: July 2008

A layer of compressive residual stress extending from the surface of a component can help to extend fatigue life, but it must remain stable during applied service loading. Metal shot and glass bead peening are traditionally used; introducing a shallow (100–300μm) layer of compressive residual stress and a highly cold worked surface. Laser peening and deep rolling are capable of introducing much deeper compressive residual stresses combined with lower levels of cold work. In this paper we report on the level of shakedown of residual stress brought about by constant strain amplitude fatigue. Glass and metal shot peened, laser peened and deep rolled Ti-6Al-4V samples have been studied. The residual stress profiles as a function of depth have been measured using neutron diffraction, laboratory x-ray diffraction and a hybrid hole-drilling/laboratory x-ray diffraction method. The magnitude and depth of cold work determined for each of the treatment methods. The extent of subsequent residual stress shakedown under different strain amplitudes and load ratios, in deep rolled, glass bead and metal shot peened samples is also assessed.
An Improved Meshfree Method for Fracture Analysis of Cracks
Authors: Chowdhury Rajib , Rao B. N. , Meher Prasad A.
Published: July 2008

This paper presents an efficient meshless method for analyzing linear-elastic cracked structures subject to single- or mixed-mode loading conditions. The method involves an element-free Galerkin formulation in conjunction with an exact implementation of essential boundary conditions and a new weight function. The proposed method eliminates the shortcomings of Lagrange multipliers typically used in element-free Galerkin formulations. Numerical examples show that the proposed method yields accurate estimates of stress-intensity factors and near-tip stress field in two-dimensional cracked structures. Since the method is meshless and no element connectivity data are needed, the burdensome remeshing required by finite element method (FEM) is avoided. By sidestepping remeshing requirement, crack-propagation analysis can be dramatically simplified. An example problem on mixed-mode condition is presented to simulate crack propagation. The agreement between the predicted crack trajectories by the proposed meshless method and FEM is excellent. In recent years, a class of Galerkin-based meshfree or meshless methods have been developed that do not require a structured mesh to discretize the problem, such as the element-free Galerkin method, and the reproducing kernel particle method. These methods employ a moving least-squares approximation method that allows resultant shape functions to be constructed entirely in terms of arbitrarily placed nodes. Meshless discretization presents significant advantages for modeling fracture propagation. Since no element connectivity data are needed, the burdensome remeshing required by the finite element method (FEM) is avoided. A growing crack can be modeled by simply extending the free surfaces, which correspond to the crack. Although meshless methods are attractive for simulating crack propagation, because of the versatility, the computational cost of a meshless method typically exceeds the cost of a regular FEM. Also in some cases, the MLS which is the bases of the meshless method may form an ill-conditioned system of equations so that the solution cannot be correctly obtained. Hence, in this paper, we propose an improved element-free Galerkin method based on an improved moving least-square approximation (IMLS) method. In the IMLS method, the orthogonal function system with a weight function is used as the basis function. The IMLS has higher computational efficiency and precision than the MLS, and will not lead to an ill-conditioned system of equations. Numerical examples are presented to illustrate the computational efficiency and accuracy of the proposed improved element-free Galerkin method.
Development of New S-N Curves Based on Small Crack Methodology
Authors: Chattopadhyay Som , Hu Juan
Published: July 2008

The propagation behavior of short cracks cannot be studied by linear elastic methods because of large plastic region near the crack tip, as well as a breakdown in correlation of the stress intensity factor with the fatigue crack growth rates. The proposed fatigue design approach incorporates a distance parameter in conjunction with linear elastic fracture mechanics and effectively integrates long and short crack growth test data. This distance parameter is a material constant that allows for the effects of (a) large-scale plasticity, (b) crack closure and (c) fatigue crack threshold. Furthermore, this parameter can be used to successfully predict fatigue crack growth behavior of short cracks. The practical application of this method to study fatigue crack initiation in pressure vessels rests on the concept that initiation occurs only when the material ahead of the crack tip is damaged enough by cyclic straining. The initiation and growth of small cracks have been investigated along with consideration for crack closure.
Universal J-Integral to Assess Multiaxial Low Cycle Fatigue
Authors: Itoh Takamoto , Sakane Masao , Tchankov Dimitar , Hamada Naomi
Published: July 2008

This paper proposes the universal J-integral for correlating multiaxial low cycle fatigue lives, utilizing the crack opening displacement approach. The universal J-integral is a function of Young’s modulus, yield stress, strain biaxiality and specimen geometry, so that it is not necessary to conduct multiaxial low cycle fatigue tests to determine the universal J-integral. To derive the universal J-integral, J-integral for a biaxially loaded Mode I crack was equated with the equivalent strain based on crack opening displacement (COD strain). The COD strain is a parameter to express the strain intensity ahead of a Mode I crack subjected to biaxial strains, normal and parallel to the crack. The J-integral was shown to be a suitable parameter for correlating crack propagation rates in the biaxial straining conditions. The J-integral was extended to a parameter, named the universal J-integral, to correlate multiaxial low cycle fatigue lives, taking account of the material dependency. The universal J-integral successfully correlated the multiaxial low cycle fatigue lives of type 304 stainless steel, Cr-Mo-V steel, Inconel 738 LC nickel base superalloy and Sn-37Pb eutectic solder universally within a factor of three scatter band independent on the material.
Adapted SIP Solver to Two Dimensional Unstructured Grids
Authors: Monteiro Eliseu , Rouboa Abel
Published: July 2008

A better knowledge of solidification time of materials in foundry manufactures will help to reduce the cost production especially for shapes with complex geometries configuration. These shapes affect the solidification conditions and subsequent cooling. Numerical simulation and/or experiments facilitate selection of appropriate materials, reducing cycle times and minimizing production costs. In the present paper, simulations of heat transfer phenomena between metal and mould are rigorously done by solving the heat transfer balance between shape and mould during the phase change. Mathematical model of cooling is investigated, according to material phases change and the interface condition between mould and shape. Due to the complex geometry of the mould, finite volume method using generalized curvilinear formulation is described. A SIP (Strongly Implicit Procedure) solver is adapted in this scenario. The solver performance is compared with solutions of thermal evolution of a slab with infinite length and circular cross-section. Results shown that the iterative method using SIP solver has faster convergence, higher precision and lower cost in term of CPU time (Computing Process Unit) than the other solver available on literature. When the convergence criterion decrease from 10−5 to 10−3, the corresponding temperature difference is insignificant in this type of physical problem.
Technical Basis for Revision of Inspection Requirements for Regenerative and Residual Heat Exchangers
Authors: Bamford Warren , Bishop Bruce , Haessler Richard , Bowler Mark
Published: July 2008

Section XI imposed volumetric inservice inspection requirements on heat exchangers in nuclear plants after most of this equipment was designed and installed. Consequently the equipment was not designed for ultrasonic examination, and in some cases such volumetric examination is not justified. The man-rem dose received from the ultrasonic inspection of some of these components is very high, and there are no known mechanisms of degradation; thus, the volumetric inspection serves no useful purpose. With the use of the newly approved code case, N706, volumetric and surface inspection of the regenerative and residual heat exchangers in PWR plants may be replaced with a visual inspection. These two heat exchangers have high irradiation fields, and both have a number of complicated weld geometries that are difficult to inspect. The regenerative heat exchanger provides preheat for the normal charging water going into the reactor coolant system (RCS). The residual heat exchanger is designed to cool the RCS during plant shut down operations. The technical basis for changing these inspection requirements was derived from four fundamental arguments: 1. The heat exchangers were carefully constructed to nuclear quality requirements. 2. They were inspected during construction, and then during service, and there is no history of degradation. 3. The flaw tolerance of the components is very high, since their duty cycle is mild, and they are constructed of stainless steel. 4. The risk is not significantly changed by replacement of the examinations with visual examinations. This paper will describe in detail the technical arguments under each of these topics, which together form the basis for the code case.
Technical Basis for Structural Integrity Performance Criterion for Steam Generator Tubing
Authors: Cipolla Russell C. , Begley James A. , Keating Robert F.
Published: July 2008

General Design Criteria (GDC) 1, 2, 4, 14, 30, 31 and 32 of 10 CFR Part 50, Appendix A, define requirements for the reactor coolant pressure boundary (RCPB) with respect to structural and leakage integrity [1]. Steam generator tubing and tube repairs constitute a major fraction of the RCPB surface area. Steam generator tubing and associated repair techniques and components, such as sleeves, must be able to maintain reactor coolant inventory and pressure. The Structural Integrity Performance Criterion (SIPC) from Nuclear Energy Institute (NEI) 97-06 [2] was developed to provide reasonable assurance that a steam generator tube will not burst during normal or postulated accident conditions. This paper presents the SIPC and its technical basis.
Computer Based Process Piping Stress Analysis: ASME B31.3 Appendix S — Example S2
Authors: Edwards Don R.
Published: July 2008

The American Standards Association (ASA) B31.3-1959 Petroleum Refinery Piping Code [1] grew out of an ASA document that addressed all manner of fluid conveying piping systems. ASA B31.3 was created long before widespread engineering use of computer “mainframes” or even before the inception of piping stress analysis software. Also as B31.3 continued to pass thru standards organizations from ASA, ANSI, to ASME, the B31.3 Process Piping Code [2] (hereafter referred to as the “Code”) has remained ambiguous over the past few decades in several areas. The displacement stress range, SE, has always been explicitly defined by both verbiage and equation. Yet, the sustained condition(s) stress, SL, is mentioned not with an explicit equation but with a statement that the sustained stress shall be limited by the allowable stress at the corresponding operating temperature, Sh. Also one might infer from the vague verbiage in the Code that there is only one sustained condition; this would also be an incorrect inference. Also, assumptions would then have to be made as to which supports are allowed to be included in a sustained analysis based on whether the piping “lifts-off” any of the pipe supports during the corresponding operating condition. This paper describes the subtle yet possibly radical concepts that are included in the (recently approved for inclusion into) ASME B31.3-2006 Appendix S Example S2. This paper discusses: • when and in what manner the most severe set of operating temperature and pressure is to be used; • the concept of “sustained condition” and multiple “anticipated” sustained conditions; • determining the support scenario(s) for each anticipated sustained condition; • establishing the most severe sustained condition to evaluate and determine the stress due to sustained loads, SL; • utilizing an equation with sustained stress indices to evaluate SL; • establishing the least severe sustained condition and its effect in determining the largest displacement stress range, SE.
Novel Washer as Force Transducer for Monitoring Clamping Force of Bolted Joints
Authors: Hung Y. Y. , Huang Y. H. , Liu L.
Published: July 2008

Bolts are widely used in industry for joining members together. The behavior and service life of bolted joints depend on several factors like bolt material, dimensions, surface finish, surface coating and thread tolerances. However, the uppermost factor affecting the reliability and durability is the correctness of the clamping force exerted by the bolt. Thus it is very important to monitor the bolt clamping force during assembly process to ensure a proper preload. Each of the available monitoring techniques including torque control, torque-angle control, strain gaged bolt and ultrasound suffers one or more limitations rendering the methods impractical for application in a production environment. In this paper, we propose an alternative method for determining clamping force. The method utilizes a simple washer whose surface has a speckle pattern; the speckle pattern acts as a strain sensor. By measuring the deformation of the washer using an image processing technique called fast digital image correlation, the clamping force can be determined. This method, which enables real-time monitoring of clamping force during fastening, has a potential of being used for mass measurement of clamping force in a production environment. Experiments conducted on a bolted structure with washers of different sizes have demonstrated the reliability and usefulness of this new approach.
European Pressure Vessel Standards: Further Progress
Authors: Haynes Ed
Published: July 2008

Publication of the main European pressure equipment standards in May 2002 coincided with the end of the transition period for introduction of the Pressure Equipment Directive. This comprehensive series of standards, replacing the many former national standards in Europe, extends to some 300 standards and another 600 supporting standards. Completing the program and further developing these standards continues to involve extensive collaborative effort, selecting the best practices from the enlarged European Union and elsewhere in the world. Account is being taken of technical and commercial considerations, design by analysis techniques, and best practices in permanent joining, non-destructive testing and materials manufacture. In addition, research work has been carried out to justify or confirm radical approaches to the entire process of design, manufacture, installation and operation of pressure equipment. This paper updates the further progress with some of the standards, in particular in relation to the use of aluminium and cast iron materials in pressure vessels, test pressures, further developments in the use of design techniques, and aspects of creep design. Mention is also made of the ways in which practical experience is being fed back into the standards-making processes to ensure that economic aspects continue to be balanced with safety considerations within an overall structured intellectual framework.
Control Mechanisms of Stress Redistribution Locus in Structures
Authors: Kasahara Naoto , Furuhashi Ichiro
Published: July 2008

Dependency of results of structural analysis on constitutive equations obstructs the application of inelastic analysis methods to design. To overcome this difficulty, a realistic inelastic analysis approach assisted by the stress redistribution locus (SRL) has been proposed for the purpose of design application. The basis of this approach is the existence of an unique SRL in each structure. The final goal of this study is to assure the uniqueness of SRL. To clarify control mechanisms of SRLs in structures, elastic-plastic and elastic-creep behaviors of fundamental structures are analyzed. The first model is a stepped bar model subjected to a tension load. The second one is a stepped beam model subjected to a bending load. It is revealed that the elastic cores control SRLs in structures, therefore that SRLs are independent of constitutive equations. Structures with large elastic cores have steep SRLs because elastic cores constrict strain. When elastic cores are reduced, SRLs gradually change from steep to gentle as the constraint becomes weaker. Under bending load, elastic cores shrink to the neutral axis in the same way. Therefore, many structure mainly subjected to bending load have similar SRLs.
Application of Risk-Based Inspection in Safety Assessment of Pressure Equipment of Chinese Petrochemical Plants
Authors: Chen Xuedong , Yang Tiecheng , Wang Bing , Ai Zhibin , Cheng Chuanqing
Published: July 2008

In this paper the effect of quantitative RBI work carried out by the authors in recent years on ten sets of plants of six large-scale petrochemical enterprises in SINOPEC and PetroChina system using BV’s RB.eye® software and database is introduced, several outstanding problems about application of RBI in Chinese petrochemical plants are discussed and suggestions about further development of RBI works in the future are proposed.
Brittle Fracture of Thin Wall Pressure Equipment
Authors: Ogayu Yasushi
Published: July 2008

Even for ferritic materials, it has been assumed that no consideration for the brittle fracture at low temperature is necessary on condition that the wall thickness of pressure equipment is less than roughly half an inch (12.7mm) from industrial experience. Nevertheless, brittle fracture incident occurred at a welded joint of a carbon steel pipeline used for transportation of crude oil at low temperature of −6°C in one of our refineries recently. The pipeline was 12.0 mm in thickness and it was found that significant crack-like flaw existed along inside of the welded joint. In this study, the assessment of the brittle fracture of thin wall welded joint with crack-like flaw was performed in accordance with Section 9 in API RP 579 (2000). Then it was concluded that brittle fracture assessment is necessary regardless of the wall thickness when significant crack-like-flaw is detected in pressure equipment, especially at low temperature condition.
Comment on "Major Australian-Antarctic Plate Reorganization at Hawaiian-Emperor Bend Time"
Authors: Tikku Anahita A. , Direen Nicholas G.
Published: July 2008

Whittaker
et al
. (Reports, 5 October 2007, p. 83) presented reconstructions for Australia and Antarctica showing a change in relative plate motion ∼53 million years ago, coincident with an inferred major global plate reorganization. This comment addresses problematic areas in their assumptions and the geological consequences of their reconstructions.
The Crystal Structure of [Fe]-Hydrogenase Reveals the Geometry of the Active Site
Authors: Shima Seigo , Pilak Oliver , Vogt Sonja , Schick Michael , Stagni Marco S. , Meyer-Klaucke Wolfram , Warkentin Eberhard , Thauer Rudolf K. , Ermler Ulrich
Published: July 2008

Biological formation and consumption of molecular hydrogen (H
2
) are catalyzed by hydrogenases, of which three phylogenetically unrelated types are known: [NiFe]-hydrogenases, [FeFe]-hydrogenases, and [Fe]-hydrogenase. We present a crystal structure of [Fe]-hydrogenase at 1.75 angstrom resolution, showing a mononuclear iron coordinated by the sulfur of cysteine 176, two carbon monoxide (CO) molecules, and the sp
2
-hybridized nitrogen of a 2-pyridinol compound with back-bonding properties similar to those of cyanide. The three-dimensional arrangement of the ligands is similar to that of thiolate, CO, and cyanide ligated to the low-spin iron in binuclear [NiFe]- and [FeFe]-hydrogenases, although the enzymes have evolved independently and the CO and cyanide ligands are not found in any other metalloenzyme. The related iron ligation pattern of hydrogenases exemplifies convergent evolution and presumably plays an essential role in H
2
activation. This finding may stimulate the ongoing synthesis of catalysts that could substitute for platinum in applications such as fuel cells.
Manipulating the Metazoan Mitochondrial Genome with Targeted Restriction Enzymes
Authors: Xu Hong , DeLuca Steven Z. , O'Farrell Patrick H.
Published: July 2008

High copy number and random segregation confound genetic analysis of the mitochondrial genome. We developed an efficient selection for heritable mitochondrial genome (mtDNA) mutations in
Drosophila
, thereby enhancing a metazoan model for study of mitochondrial genetics and mutations causing human mitochondrial disease. Targeting a restriction enzyme to mitochondria in the germline compromised fertility, but escaper progeny carried homoplasmic mtDNA mutations lacking the cleavage site. Among mutations eliminating a site in the cytochrome c oxidase gene,

mt:CoI
A302T

was healthy,

mt:CoI
R301L

was male sterile but otherwise healthy, and

mt:CoI
R301S

exhibited a wide range of defects, including growth retardation, neurodegeneration, muscular atrophy, male sterility, and reduced life span. Thus, germline expression of mitochondrial restriction enzymes creates a powerful selection and has allowed direct isolation of mitochondrial mutants in a metazoan.
Identification and Characterization of Two Strains of Human Parechovirus 4 Isolated from Two Clinical Cases in Fukuoka City, Japan
Authors: Wakatsuki Kiyoko , Kawamoto Daisuke , Hiwaki Hiroshi , Watanabe Kanako , Yoshida Hiromu
Published: July 2008

Reverse transcription-PCR targeting the VP0 gene of human parechoviruses (HPeVs) was used to identify two isolates from two Japanese children's stool specimens. Molecular analysis revealed that these isolates belonged to HPeV type 4, and their nucleotide identity in the P1 region was 85.0%.
Misidentification of
Pandoraea sputorum
Isolated from Sputum of a Patient with Cystic Fibrosis and Review of
Pandoraea
Species Infections in Transplant Patients
Authors: Pimentel Jason D. , MacLeod Colin
Published: July 2008

Pandoraea
species are considered emerging pathogens in cystic fibrosis (CF) patients, but few data exist regarding outcomes of patients colonized with these organisms. We report a case of
Pandoraea sputorum
colonization in a CF patient under consideration for lung transplantation and review five cases of lung transplantation involving
Pandoraea
species.
Subtype-Specific Suppression of Shiga Toxin 2 Released from
Escherichia coli
upon Exposure to Protein Synthesis Inhibitors
Authors: Pedersen Malene Gantzhorn , Hansen Claus , Riise Erik , Persson Søren , Olsen Katharina E. P.
Published: July 2008

Shiga toxins (Stx) are important virulence factors in the pathogenesis of severe disease including hemolytic-uremic syndrome, caused by Stx-producing
Escherichia coli
(STEC). STEC strains increase the release of Stx in vitro following the addition of fluoroquinolones, whereas protein synthesis inhibitors previously have been reported to suppress the release of Stx. The amount of Stx released from wild-type STEC strains incubated with protein synthesis inhibitors was examined by a Vero cell cytotoxicity assay. The amounts released were compared to the Stx type (Stx1 or Stx2) and additionally to the individual subtypes and toxin variants of Stx2. In general, Stx2 release was suppressed significantly upon exposure to protein synthesis inhibitors at MICs, which was not observed in the case of Stx1. Also, the average amount of different Stx2 toxin variants released was suppressed to various levels ranging from 14.0% (Stx2-O157-EDL933) to 94.7% (Stx2d-O8-C466-01B). Clinical studies exploring protein synthesis inhibitors as future candidates for treatment of intestinal infections caused by Stx2-producing STEC should therefore include knowledge of the toxin variant in addition to the subtype.
Pan-Dengue Virus Detection by PCR for Travelers Returning from the Tropics
Authors: Dumoulin Alexis , Marti Hanspeter , Panning Marcus , Hatz Christoph , Hirsch Hans H.
Published: July 2008

We performed dengue virus (DENV) serology and quantitative real-time pan-DENV reverse transcription-PCR (RT-PCR) on 186 sera of 171 patients returning from the tropics. DENV loads significantly decreased with increasing times of disease and were higher in immunoglobulin M-negative samples. In the first week of disease, pan-DENV RT-PCR is the test of choice.
Functional Characterization of the Human Immunodeficiency Virus Type 1 Nef Acidic Domain
Authors: Baugh Laura L. , Garcia J. Victor , Foster John L.
Published: July 2008

The human immunodeficiency virus type 1 (HIV-1) accessory protein Nef downregulates major histocompatibility complex class I (MHC-I) from the cell surface. It has been proposed that the direct interaction of the acidic cluster (AC) of Nef,
62
EEEE
65
, with the furin binding region (fbr) of PACS-1 is crucial for this Nef function. Contrary to this proposal, evidence is presented here that the four glutamates in Nef do not functionally engage the PACS-1 fbr. (i) The binding of Nef to the PACS-1 fbr in vitro is much weaker than the binding of the canonical furin AC to the PACS-1 fbr. (ii) The mutation of two of the four glutamates in Nef's AC to alanines does not alter Nef's ability to downregulate MHC-I, and triply mutated Nefs exhibit 50% activity. (iii) The introduction of lysine into the AC has little effect on Nef function. (iv) The mutation of all four glutamates to alanine does debilitate Nef MHC-I downregulation, but this quadruple mutation also impairs the ability of Nef to regulate p21-activated protein kinase and enhance viral particle infectivity. (v) The replacement of the Nef AC with the bona fide AC from furin results in the loss of the expected regulatory properties of the furin AC. (vi) The insertion of the conformation-disrupting amino acid proline into the Nef AC does not disrupt MHC-I downregulation. Our results are consistent with an alternative model in which
62
EEEE
65
plays a stabilizing role in the formation of a ternary complex between Nef, the MHC-I cytoplasmic domain, and AP-1.
Transcriptional Control of Spliced and Unspliced Human T-Cell Leukemia Virus Type 1 bZIP Factor (
HBZ
) Gene
Authors: Yoshida Mika , Satou Yorifumi , Yasunaga Jun-ichirou , Fujisawa Jun-ichi , Matsuoka Masao
Published: July 2008

The human T-cell leukemia virus type 1 (HTLV-1) basic leucine zipper factor (
HBZ
) gene is encoded by the minus strand of the HTLV-1 provirus and transcribed from the 3′ long terminal repeat (LTR).
HBZ
gene expression not only inhibits the Tax-mediated activation of viral gene transcription through the 5′ LTR but also promotes the proliferation of infected cells. However, the
HBZ
promoter region and the transcriptional regulation of the gene have not been studied. In this study, we characterize the promoters of the spliced version of the
HBZ
gene (s
HBZ
) and the unspliced version of the
HBZ
gene (us
HBZ
) by luciferase assay. Both promoters were TATA-less and contained initiators and downstream promoter elements. Detailed studies of the promoter for the s
HBZ
gene showed that Sp1 sites were critical for its activity. The activities of the s
HBZ
and us
HBZ
gene promoters were upregulated by Tax through Tax-responsible elements in the 3′ LTR. We compared the functions of the proteins derived from the s
HBZ
and us
HBZ
transcripts. sHBZ showed a stronger suppression of Tax-mediated transcriptional activation through the 5′ LTR than did usHBZ; the level of suppression correlated with the level of protein produced. The expression of s
HBZ
had a growth-promoting function in a T-cell line, while us
HBZ
expression did not. This study demonstrates that Sp1 is critical for s
HBZ
transcription, which accounts for the constitutive expression of the s
HBZ
gene. Functional differences between s
HBZ
and us
HBZ
suggest that the s
HBZ
gene plays a significant role in the proliferation of infected cells.
Polymerase Read-Through at the First Transcription Termination Site Contributes to Regulation of Borna Disease Virus Gene Expression
Authors: Poenisch Marion , Wille Sandra , Staeheli Peter , Schneider Urs
Published: July 2008

An unusually long noncoding sequence is located between the N gene of Borna disease virus (BDV) and the genes for regulatory factor X and polymerase cofactor P. Most of these nucleotides are transcribed and seem to control translation of the bicistronic X/P mRNA. We report here that Vero cells persistently infected with mutant viruses containing minor alterations in this control region showed almost normal levels of N, X, and P proteins but exhibited greatly reduced levels of mRNAs coding for these viral gene products. Surprisingly, cells infected with these BDV mutants accumulated a viral transcript 1.9 kb in length that represents a capped and polyadenylated mRNA containing the coding regions of the N, X, and P genes. Cells infected with wild-type BDV also contained substantial amounts of this read-through mRNA, which yielded both N and P protein when translated in vitro. Viruses carrying mutations that promoted read-through transcription at the first gene junction failed to replicate in the brain of adult rats. In the brains of newborn rats, these mutant viruses were able to replicate after acquiring second-site mutations in or near the termination signal located downstream of the N gene. Thus, sequence elements adjacent to the core termination signal seem to regulate the frequency by which the polymerase terminates transcription after the N gene. We conclude from these observations that BDV uses read-through transcription for fine-tuning the expression of the N, X, and P genes which, in turn, influence viral polymerase activity.
The F-Like Protein Ac23 Enhances the Infectivity of the Budded Virus of
gp64
-Null
Autographa californica
Multinucleocapsid Nucleopolyhedrovirus Pseudotyped with Baculovirus Envelope Fusion Protein F
Authors: Wang Manli , Tan Ying , Yin Feifei , Deng Fei , Vlak Just M. , Hu Zhihong , Wang Hualin
Published: July 2008

The GP64 and F proteins were previously identified as the sole functional envelope fusion proteins in
Baculoviridae
. F-like proteins, present only in group I nucleopolyhedroviruses (NPVs), are remnant, nonfunctional F proteins. In this report, we describe the effect of the presence or absence of the F-like protein Ac23 in a
gp64
-null
Autographa californica
multinucleocapsid NPV pseudotyped with the F protein from
Spodoptera exigua
multicapsid NPV (SeF). We found that the presence of Ac23 elevates the infectivity of the pseudotyped virus. This is in contrast to the results of Lung et al. (J. Virol. 76:5729-5736, 2002), who found no such effect. The possible reasons for the differing results are discussed.
Cytopathogenicity of Classical Swine Fever Virus Correlates with Attenuation in the Natural Host
Authors: Gallei Andreas , Blome Sandra , Gilgenbach Stefanie , Tautz Norbert , Moennig Volker , Becher Paul
Published: July 2008

For the important livestock pathogens classical swine fever virus (CSFV) and bovine viral diarrhea virus (BVDV), cytopathogenic (cp) and non-cp viruses are distinguished according to the induction of apoptosis in infected tissue culture cells. However, it is currently unknown whether cp CSFV differs from non-cp CSFV with regard to virulence in the acutely infected host. In this study, we generated helper virus-independent CSFV Alfort-Jiv, which encompasses sequences encoding domain Jiv-90 of cellular J-domain protein interacting with viral protein (Jiv). Expanding the knowledge of BVDV, our results suggest that Jiv acts as a regulating cofactor for the nonstructural (NS) protein NS2 autoprotease of CSFV and initiates NS2-3 cleavage in
trans
. For Alfort-Jiv, the resulting expression of large amounts of NS3 correlated with increased viral RNA synthesis and viral cytopathogenicity. Moreover, both cp Alfort-Jiv and the parental non-cp CSFV strain Alfort-p447 efficiently replicate in cell culture. Animal experiments demonstrated that in contrast to parental non-cp Alfort-p447, infection with cp Alfort-Jiv did not cause disease in pigs but induced high levels of neutralizing antibodies, thus elucidating that cp CSFV is highly attenuated in its natural host. In contrast to virulent Alfort-p447, the attenuated CSFV strain Alfort-Jiv induces the expression of cellular Mx protein in porcine PK-15 cells. Accordingly, the remarkable difference between cp and non-cp CSFV with regard to the ability to cause classical swine fever in pigs correlates with different effects of cp and non-cp CSFV on cellular antiviral defense mechanisms.
Adenovirus E4orf4 Protein DownregulatesMYCExpression through Interaction with the PP2A-B55 Subunit
Authors: Ben-Israel Haggit , Sharf Rakefet , Rechavi Gideon , Kleinberger Tamar
Published: July 2008

The adenovirus E4 open reading frame 4 (E4orf4) protein is a multifunctional viral regulator that is involved in the temporal regulation of viral gene expression by modulating cellular and viral genes at the transcription and translation levels and by controlling alternative splicing of adenoviral late mRNAs. When expressed individually, E4orf4 induces apoptosis in transformed cells. Using oligonucleotide microarray analysis, validated by quantitative real time PCR, we found thatMYC(also known as c-Myc) is downregulated early after the induction of E4orf4 expression. As a result, Myc protein levels are reduced in E4orf4-expressing cells.MYCdownregulation is observed both when E4orf4 is expressed individually and within the context of viral infection. E4orf4 reducesMYCtranscription but does not affect transcriptional elongation or RNA stability. An interaction with the PP2A-B55 subunit is required for the downregulation ofMYCby E4orf4. Since Myc overexpression was previously shown to inhibit adenovirus replication, the downregulation of Myc by E4orf4 would contribute to efficient virus infection.
Quantitative Whole-Cell Proteome Analysis of Pseudorabies Virus-Infected Cells
Authors: Skiba Martin , Mettenleiter Thomas C. , Karger Axel
Published: July 2008

A quantitative proteome study using the stable isotope labeling with amino acids in cell culture technique was performed on bovine kidney cells after infection with the alphaherpesvirus pseudorabies virus (PrV), the etiological agent of Aujeszky's disease. To enhance yields of proteins to be identified, raw extracts were fractionated by affinity solid-phase extraction with a combination of a cibacron blue F3G-A and a heparin matrix and with a phosphoprotein-specific matrix. After two-dimensional gel electrophoresis in different pH ranges between pH 3 and pH 10, 2,600 proteins representing 565 genes were identified by mass spectrometry and screened for virus-induced changes in relative protein levels. Four hours after infection, significant quantitative variations were found for constituents of the nuclear lamina, representatives of the heterogeneous nuclear ribonucleoproteins, proteins involved in membrane trafficking and intracellular transport, a ribosomal protein, and heat shock protein 27. Several proteins were present in multiple charge variants that were differentially affected by infection with PrV. As a common pattern for all these proteins, a mass shift in favor of the more acidic isoforms was observed, suggesting the involvement of viral or cellular kinases.
Philanthropy, politics and promotion: Philip Morris’ “charitable contributions” in Thailand
Authors: MacKenzie Ross , Collin Jeff
Published: July 2008

The efforts of members of the tobacco industry to portray themselves as responsible corporations via ostensible commitment to improved labour practices and public philanthropy have attracted growing criticism. This is particularly true of corporate social responsibility (CSR) schemes undertaken in emerging nations that are designed to rehabilitate the tobacco industry’s image among public, government and market opinions in North America and western Europe. In the case of Thailand, sponsorship of arts events and community groups has been one avenue of promoting the industry in a regulatory environment that severely curtails promotion and advertising. The Association of Southeast Asian Nations (ASEAN) Art Award, sponsored by Philip Morris (PM) has provided one such outlet for 10 years. Analysis of PM funding announcements since the end of the ASEAN art programme in Thailand reveals that recent donations to tobacco-related community organisations reinforces the extent to which seemingly generous acts are driven by corporate self-interest rather than social responsibility.
Public attitudes towards smoking and tobacco control policy in Russia
Authors: Danishevski K , Gilmore A , McKee M
Published: July 2008

Background:

Since the political transition in 1991, Russia has been targeted intensively by the transnational tobacco industry. Already high smoking rates among men have increased further; traditionally low rates among women have more than doubled. The tobacco companies have so far faced little opposition as they shape the discourse on smoking in Russia. This paper asks what ordinary Russians really think about possible actions to reduce smoking.

Methods:

A representative sample of the Russian population (1600 respondents) was interviewed face to face in November 2007.

Results:

Only 14% of respondents considered tobacco control in Russia adequate, while 37% thought that nothing was being done at all. There was support for prices keeping pace with or even exceeding inflation. Over 70% of all respondents favoured a ban on sales from street kiosks, while 56% believed that existing health warnings (currently 4% of front and back of packs) were inadequate. The current policy of designating a few tables in bars and restaurants as non-smoking was supported by less than 10% of respondents, while almost a third supported a total ban, with 44% supporting provision of equal space for smokers and non-smokers. Older age, non-smoking status and living in a smaller town all emerged as significantly associated with the propensity to support antismoking measures. The tobacco companies were generally viewed as behaving like most other companies in Russia, with three-quarters of respondents believing that these companies definitely or maybe bribe politicians. Knowledge of impact of smoking on health was limited with significant underestimation of dangers and addictive qualities of tobacco. A third believed that light cigarettes are safer than normal cigarettes.

Conclusion:

The majority of the Russian population would support considerable strengthening of tobacco control policies but there is also a need for effective public education campaigns.
Systematics of Capparaceae and Cleomaceae: an evaluation of the generic delimitations of Capparis and Cleome using plastid DNA sequence dataThis paper is one of a selection of papers published in the Special Issue on Systematics Research.
Authors: Hall Jocelyn C.
Published: July 2008

The phylogenetic relationships in Capparaceae and Cleomaceae were examined using two plastid genes, ndhF and matK, to address outstanding systematic questions in the two families. Specifically, the monophyly of the two type genera, Capparis and Cleome , has recently been questioned. Capparaceae and Cleomaceae were broadly sampled to assess the generic circumscriptions of both genera, which house the majority of species for each family. Phylogenetic reconstructions using maximum parsimony and maximum likelihood methods strongly contradict monophyly for both type genera. Within Capparaceae, Capparis is diphyletic: the sampled species belong to two of the five major lineages recovered in the family, which corresponds with their geographic distribution. One lineage contains all sampled New World Capparis and four other genera ( Atamisquea , Belencita , Morisonia , and Steriphoma ) that are distributed exclusively in the New World. The other lineage contains Capparis species from the Old World and Australasia, as well as the Australian genus, Apophyllum . Species of Cleome are scattered across each of four major lineages identified within Cleomaceae: (i) Cleome in part, Dactylaena , Dipterygium , Gynandropsis , Podandrogyne , and Polanisia ; (ii) Cleome droserifolia (Forssk.) Del.; (iii)  Cleome arabica L., and Cleome ornithopodioides L.; and (iv) Cleome in part, Cleomella , Isomeris , Oxystylis , and Wislizenia . Resolution within and among these major clades of Cleomaceae is limited, and there is no clear correspondence of clades with geographic distribution. Within each family, morphological support and taxonomic implications of the molecular-based clades are discussed.