bluuebunny/crossref_metadata_2025_split huggingface dataset:
Standardized Through-Wall Distributions of Dissimilar Metal Weld Residual Stress
Authors: Broussard John E. 
Published: November 2015

The residual stresses imparted by the welding process are a principal factor in the process of primary water stress corrosion cracking (PWSCC) of Alloy 82/182 nickel-alloy (i.e., dissimilar metal or DM) piping butt welds in PWRs. While Section XI of the ASME Code requires that residual stresses are considered in crack growth calculations, there is little guidance or requirement on how to calculate them. Analytical models are frequently used to simulate the welding process in order to predict the residual stress distribution in the weld and base material as an input to crack growth calculations. The crack growth calculations, in turn, have demonstrated a high sensitivity to the welding residual stress distribution inputs.
While significant progress has been made in understanding and reducing the variability in calculated residual stress among modelers as well as the variability in measured residual stress among different techniques, there remains some uncertainty regarding any given measured or calculated distribution. A feasible alternative to calculating through-wall stress distributions with analytical models on a case-by-case basis is to develop a set of standardized through-wall stress distributions that are applicable to DM welds. Examples of standardized through-wall distributions for residual stress are found in numerous consensus code and standards. The benefit of established through-wall stress distributions is that evaluations for flaws in welds would start from a uniform basis on one of the key inputs to the crack growth calculation, reducing the time required to perform and review flaw evaluations.
This paper presents and describes the technical basis for a set of through-wall distributions for common DM welds found in the US nuclear industry. The basis of the distributions include the results of analytical models, including uncertainty, as well as measured data for through-wall stress in DM welds.
Large EDF Tests on Aged Cast Duplex Stainless Steel Components: Part I — Reduced Scale Tests
Authors: Le Delliou Patrick , Saillet Sébastien , Bezdikian Georges 
Published: November 2015

Thermal ageing of cast duplex stainless steel primary loops components (elbows, pump casings and branch connections) is a concern for long-term operation of EDF nuclear power plants. The thermal ageing embrittlement results from the micro-structural evolution of the ferrite phase (spinodal decomposition), and can reduce the fracture toughness properties of the steel. In addition, it is necessary to consider manufacturing quality and the possible occurrence of casting defects such as shrinkage cavities. In a context of life extension, it is important to assess the safety margins to crack initiation and crack propagation instability.
This paper presents several tests conducted by EDF on aged cast duplex stainless steel NPP components, respectively on two-third scale elbows and welded mock-ups. The main characteristics of the tests are recalled, the results are presented, and finally, the lessons drawn are summarized.
These tests and their detailed analyses contribute to validate and justify the methodology used by EDF in the integrity assessment of in-service cast duplex stainless steel components.
Assessing the Impact of ASME B31.3 2012 Fatigue Rule Changes on High Strength Piping
Authors: Brown Warren 
Published: November 2015

The 2012 edition of ASME B31.3 Process Piping Code [1] included an update to the fatigue assessment rules which limited the allowable stress value used in the fatigue assessment to 138 MPa (20 ksi). This change was made due to the knowledge that higher strength materials, especially those materials with yield strength to tensile strength ratios above 0.8, do not tend to exhibit significantly longer fatigue life as compared to lower strength materials. This change means that for existing high-strength piping in plants that were designed using pre-2012 B31.3 [2] and are in fatigue service, the end-user must now recalculate the piping remaining life based on new requirements. Depending on the size of the plant under consideration and the level of high-strength piping used, such a recalculation may be an extensive scope of work.
This paper uses a comparison between the rules in ASME B31.3 and the fatigue life prediction methods outlined in API RP 579-1 / ASME FFS-1 [3] in order to establish a categorization methodology which is used to identify which pre-2012 high strength piping systems will require re-assessment, more frequent monitoring and/or may have a shorter than anticipated life than the original design basis. The methodology allows for easy categorization of the piping systems to allow efforts to be focused on the most appropriate piping systems. The need for this work came from concerns regarding the extensive use of Duplex Stainless Steel piping on a large offshore platform that was designed prior to ASME B31.3 2012.
“Live” Repair of Gas Pipeline With Deep Girth Weld Crack
Authors: Tronskar Jens P. , Törnqvist Rikard , Guan Ong Hock , Bruce William A. 
Published: November 2015

In-line inspection (ILI) of the main 48” × 21 mm wall thickness API 5L grade X70 export gas pipeline of an offshore oil and gas production field was performed. The ILI using a high resolution Magnetic Flux Leak (MFL) pig revealed an anomaly in a girth weld in the onshore portion of the pipeline. A dig campaign was organized to carry out detailed inspection and sizing of the detected anomaly by external Phased Array Ultrasonic Testing (PAUT) and Time of Flight Diffraction (TOFD). The inspection confirmed the presence of a deep external, surface breaking, girth weld crack. The presence of the defect raised concern for the integrity of the pipeline and it was a question if it was necessary to shut the line down for immediate repair or if repair could be performed at a later date.
CTOD fracture toughness testing was performed on a reproduced girth weld. The joint tested was welded using pipe remaining from installation with virtually identical chemistry and mechanical properties as the pipes joined at the cracked girth weld location according to the mill certificates. For the welding, the same welding consumables, original WPS, and the welding system (CRC-Evans system using internal line up clamp and root pass) were used.
Based on the fracture mechanics test results and the analyses performed, it was recommended to repair the pipeline as soon as practical. It was decided to repair the cracked girth weld using a full encirclement snug fitting (Type -B), welded split sleeve according to the PRCI Repair Manual. To assess the risk of welding the split sleeve onto the “live” pipe, which could increase the crack driving force due to the thermal stresses from welding and preheating, a combined 3D non-linear thermal and fracture mechanics FEA modelling of the girth weld crack and thermal distributions were performed in Abaqus. As for all welding onto “live” pipelines, the overall risk associated with burn-through and hydrogen induced heat-affected zone cracking (HAZ) was also assessed.
This paper describes the methodology applied for the assessment and qualification of the repair and the analysis of the thermal, operating and residual stresses on the crack driving force to establish if the repair operation was safe to undertake.
Blood Transcriptional Biomarkers for Active Tuberculosis among Patients in the United States: a Case-Control Study with Systematic Cross-Classifier Evaluation
Authors: Walter Nicholas D. , Miller Mikaela A. , Vasquez Joshua , Weiner Marc , Chapman Adam , Engle Melissa , Higgins Michael , Quinones Amy M. , Rosselli Vanessa , Canono Elizabeth , Yoon Christina , Cattamanchi Adithya , Davis J. Lucian , Phang Tzu , Stearman Robert S. , Datta Gargi , Garcia Benjamin J. , Daley Charles L. , Strong Michael , Kechris Katerina , Fingerlin Tasha E. , Reves Randall , Geraci Mark W. 
Published: November 2015

ABSTRACT
Blood transcriptional signatures are promising for tuberculosis (TB) diagnosis but have not been evaluated among U.S. patients. To be used clinically, transcriptional classifiers need reproducible accuracy in diverse populations that vary in genetic composition, disease spectrum and severity, and comorbidities. In a prospective case-control study, we identified novel transcriptional classifiers for active TB among U.S. patients and systematically compared their accuracy to classifiers from published studies. Blood samples from HIV-uninfected U.S. adults with active TB, pneumonia, or latent TB infection underwent whole-transcriptome microarray. We used support vector machines to classify disease state based on transcriptional patterns. We externally validated our classifiers using data from sub-Saharan African cohorts and evaluated previously published transcriptional classifiers in our population. Our classifier distinguishing active TB from pneumonia had an area under the concentration-time curve (AUC) of 96.5% (95.4% to 97.6%) among U.S. patients, but the AUC was lower (90.6% [89.6% to 91.7%]) in HIV-uninfected Sub-Saharan Africans. Previously published comparable classifiers had AUC values of 90.0% (87.7% to 92.3%) and 82.9% (80.8% to 85.1%) when tested in U.S. patients. Our classifier distinguishing active TB from latent TB had AUC values of 95.9% (95.2% to 96.6%) among U.S. patients and 95.3% (94.7% to 96.0%) among Sub-Saharan Africans. Previously published comparable classifiers had AUC values of 98.0% (97.4% to 98.7%) and 94.8% (92.9% to 96.8%) when tested in U.S. patients. Blood transcriptional classifiers accurately detected active TB among U.S. adults. The accuracy of classifiers for active TB versus that of other diseases decreased when tested in new populations with different disease controls, suggesting additional studies are required to enhance generalizability. Classifiers that distinguish active TB from latent TB are accurate and generalizable across populations and can be explored as screening assays.
Evaluation of the BD Max Enteric Parasite Panel for Clinical Diagnostics
Authors: Mölling Paula , Nilsson Peter , Ennefors Theresa , Ögren Jessica , Florén Kerstin , Thulin Hedberg Sara , Sundqvist Martin 
Published: November 2015

ABSTRACT

We compared the performance of the BD Max enteric parasite panel to routine microscopy and an in-house PCR for the detection of
Giardia intestinalis
,
Entamoeba histolytica
, and
Cryptosporidium
spp. The enteric parasite panel showed good specificity for all targets and good sensitivity for
E. histolytica
and
Cryptosporidium
spp. Sensitivity for
G. intestinalis
with the BD Max enteric parasite panel was equivalent to that with microscopy.
Evaluation of an Image Analysis Device (APAS) for Screening Urine Cultures
Authors: Glasson John , Hill Rhys , Summerford Michael , Giglio Steven 
Published: November 2015

ABSTRACT

While advancements have been made in some areas of pathology with diagnostic materials being screened using image analysis technologies, the reporting of cultures from agar plates remains a manual process. We compared the results for 2,163 urine cultures read by a reference panel of microbiologists, by the routine laboratory process, and by an automated plate reading system, APAS (LBT Innovations Ltd., South Australia). APAS detected colonies with a sensitivity of 99.1% and a specificity of 99.3% on blood agar, while on MacConkey agar, the colony detection sensitivity was 99.4% with a specificity of 99.3%. The device's ability to enumerate growth had an accuracy of 89.2%, and the morphological identification of colonies showed a high level of performance for the colony types typical of
Escherichia coli
and other enteric bacilli. On blood agar, lactose-fermenting colonies were morphologically identified with a sensitivity of 98.9%, while on MacConkey agar they were identified with a sensitivity of 99.2%. In this first clinical evaluation, APAS demonstrated high performance in the detection, enumeration, and colony classification of isolates compared with that for conventional plate-reading methods. The device found all cases reported by the laboratory and detected the most commonly encountered organisms found in urinary tract infections.
Comparative Study of a Novel Biochemical Assay, the Rapidec Carba NP Test, for Detecting Carbapenemase-Producing Enterobacteriaceae
Authors: Lifshitz Ziv , Adler Amos , Carmeli Yehuda 
Published: November 2015

ABSTRACT

The novel biochemical test, the Rapidec Carba NP (RCNP), was evaluated using carbapenemase- and non-carbapenemase-producing
Enterobacteriaceae
isolates. The RCNP test was compared with the Carba NP test (CNP) and the modified Hodge test. Compared to the CNP test, the RCNP test had identical sensitivity (96%) and lower specificity (93% versus 100%). The medium used to culture the isolates significantly affected test sensitivity and specificity. The RCNP test was quicker and easier to perform than the other tests.
A Simple and Safe Protocol for Preparing Brucella Samples for Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometry Analysis
Authors: Mesureur Jennifer , Ranaldi Sébastien , Monnin Valérie , Girard Victoria , Arend Sandrine , Welker Martin , O'Callaghan David , Lavigne Jean-Philippe , Keriel Anne 
Published: November 2015

ABSTRACT

We describe a simple protocol to inactivate the biosafety level 3 (BSL3) pathogens
Brucella
prior to their analysis by matrix-assisted laser desorption ionization–time of flight mass spectrometry. This method is also effective for several other bacterial pathogens and allows storage, and eventually shipping, of inactivated samples; therefore, it might be routinely applied to unidentified bacteria, for the safety of laboratory workers.
Commentary: Unveiling New Aspects of Meningococcal Carriage and Disease Prevention
Authors: Gottfredsson Magnus 
Published: November 2015

ABSTRACT

Recently, two protein-based vaccines have been approved for the prevention of invasive meningococcal disease caused by
Neisseria meningitidis
serogroup B (MenB). It is therefore important to study carefully if and how these pathogens respond to widespread vaccination. Traditionally, meningococci have been classified on the basis of capsular phenotypes, but variable levels of capsule expression can influence the results, mainly among MenB strains. In this issue, Jones and colleagues (J Clin Microbiol 54:25–34, 2016,
http://dx.doi.org/10.1128/JCM.01447-15
) compare whole-genome sequencing to traditional phenotypic methods of classifying meningococci. They demonstrate that for MenB in particular, sequencing-based methods are far superior to traditional methods, especially when it comes to characterizing carriage isolates. This has important implications for future surveillance.
Engineering Enhanced Vaccine Cell Lines To Eradicate Vaccine-Preventable Diseases: the Polio End Game
Authors: van der Sanden Sabine M. G. , Wu Weilin , Dybdahl-Sissoko Naomi , Weldon William C. , Brooks Paula , O'Donnell Jason , Jones Les P. , Brown Cedric , Tompkins S. Mark , Oberste M. Steven , Karpilow Jon , Tripp Ralph A. 
Published: November 2015

ABSTRACT
Vaccine manufacturing costs prevent a significant portion of the world's population from accessing protection from vaccine-preventable diseases. To enhance vaccine production at reduced costs, a genome-wide RNA interference (RNAi) screen was performed to identify gene knockdown events that enhanced poliovirus replication. Primary screen hits were validated in a Vero vaccine manufacturing cell line using attenuated and wild-type poliovirus strains. Multiple single and dual gene silencing events increased poliovirus titers >20-fold and >50-fold, respectively. Host gene knockdown events did not affect virus antigenicity, and clustered regularly interspaced short palindromic repeat (CRISPR)-Cas9-mediated knockout of the top candidates dramatically improved viral vaccine strain production. Interestingly, silencing of several genes that enhanced poliovirus replication also enhanced replication of enterovirus 71, a clinically relevant virus to which vaccines are being targeted. The discovery that host gene modulation can markedly increase virus vaccine production dramatically alters mammalian cell-based vaccine manufacturing possibilities and should facilitate polio eradication using the inactivated poliovirus vaccine.

IMPORTANCE
Using a genome-wide RNAi screen, a collection of host virus resistance genes was identified that, upon silencing, increased poliovirus and enterovirus 71 production by from 10-fold to >50-fold in a Vero vaccine manufacturing cell line. This report provides novel insights into enterovirus-host interactions and describes an approach to developing the next generation of vaccine manufacturing through engineered vaccine cell lines. The results show that specific gene silencing and knockout events can enhance viral titers of both attenuated (Sabin strain) and wild-type polioviruses, a finding that should greatly facilitate global implementation of inactivated polio vaccine as well as further reduce costs for live-attenuated oral polio vaccines. This work describes a platform-enabling technology applicable to most vaccine-preventable diseases.
Three-Dimensional Structural Characterization of HIV-1 Tethered to Human Cells
Authors: Strauss Joshua D. , Hammonds Jason E. , Yi Hong , Ding Lingmei , Spearman Paul , Wright Elizabeth R. 
Published: November 2015

ABSTRACT
Tetherin (BST2, CD317, or HM1.24) is a host cellular restriction factor that prevents the release of enveloped viruses by mechanically linking virions to the plasma membrane. The precise arrangement of tetherin molecules at the plasma membrane site of HIV-1 assembly, budding, and restriction is not well understood. To gain insight into the biophysical mechanism underlying tetherin-mediated restriction of HIV-1, we utilized cryo-electron tomography (cryo-ET) to directly visualize HIV-1 virus-like particles (VLPs) and virions tethered to human cells in three dimensions (3D). Rod-like densities that we refer to as tethers were seen connecting HIV-1 virions to each other and to the plasma membrane. Native immunogold labeling showed tetherin molecules located on HIV-1 VLPs and virions in positions similar to those of the densities observed by cryo-ET. The location of the tethers with respect to the ordered immature Gag lattice or mature conical core was random. However, tethers were not uniformly distributed on the viral membrane but rather formed clusters at sites of contact with the cell or other virions. Chains of tethered HIV-1 virions often were arranged in a linear fashion, primarily as single chains and, to a lesser degree, as branched chains. Distance measurements support the extended tetherin model, in which the coiled-coil ectodomains are oriented perpendicular with respect to the viral and plasma membranes.

IMPORTANCE
Tetherin is a cellular factor that restricts HIV-1 release by directly cross-linking the virus to the host cell plasma membrane. We used cryo-electron tomography to visualize HIV-1 tethered to human cells in 3D. We determined that tetherin-restricted HIV-1 virions were physically connected to each other or to the plasma membrane by filamentous tethers that resembled rods ∼15 nm in length, which is consistent with the extended tetherin model. In addition, we found the position of the tethers to be arbitrary relative to the ordered immature Gag lattice or the mature conical cores. However, when present as multiple copies, the tethers clustered at the interface between virions. Tethered HIV-1 virions were arranged in a linear fashion, with the majority as single chains. This study advances our understanding of tetherin-mediated HIV-1 restriction by defining the spatial arrangement and orientation of tetherin molecules at sites of HIV-1 restriction.
Origin of Rebound Plasma HIV Includes Cells with Identical Proviruses That Are Transcriptionally Active before Stopping of Antiretroviral Therapy
Authors: Kearney Mary F. , Wiegand Ann , Shao Wei , Coffin John M. , Mellors John W. , Lederman Michael , Gandhi Rajesh T. , Keele Brandon F. , Li Jonathan Z. 
Published: November 2015

ABSTRACT
Understanding the origin of HIV variants during viral rebound may provide insight into the composition of the HIV reservoir and has implications for the design of curative interventions. HIV single-genome sequences were obtained from 10 AIDS Clinical Trials Group participants who underwent analytic antiretroviral therapy (ART) interruption (ATI). Rebounding variants were compared with those in pre-ART plasma in all 10 participants and with on-ART peripheral blood mononuclear cell (PBMC)-associated DNA and RNA (CA-RNA) in 7/10 participants. The highest viral diversities were found in the DNA and CA-RNA populations. In 3 of 7 participants, we detected multiple, identical DNA and CA-RNA sequences during suppression on ART that exactly matched plasma HIV sequences. Hypermutated DNA and CA-RNA were detected in four participants, contributing to diversities in these compartments that were higher than in the pre-ART and post-ATI plasma. Shifts in the viral rebound populations could be detected in some participants over the 2- to 3-month observation period. These findings suggest that a source of initial rebound viremia could be populations of infected cells that clonally expanded prior to and/or during ART, some of which were already expressing HIV RNA before treatment was interrupted. These clonally expanding populations of HIV-infected cells may represent an important target for strategies aimed at achieving reservoir reduction and sustained virologic remission.

IMPORTANCE
Antiretroviral therapy alone cannot eradicate the HIV reservoir, and viral rebound is generally rapid after treatment interruption. It has been suggested that clonal expansion of HIV-infected cells is an important mechanism of HIV reservoir persistence, but the contribution of these clonally proliferating cells to the rebounding virus is unknown. We report a study of AIDS Clinical Trials Group participants who underwent treatment interruption and compared rebounding plasma virus with that found within cells prior to treatment interruption. We found several incidences in which plasma HIV variants exactly matched that of multiple proviral DNA copies from infected blood cells sampled before treatment interruption. In addition, we found that these cells were not dormant but were generating unspliced RNA transcripts before treatment was interrupted. Identification of the HIV reservoir and determining its mechanisms for persistence may aid in the development of strategies toward a cure for HIV. (This study was presented in part at the Conference on Retroviruses and Opportunistic Infections, Seattle, WA, February 23 to 26 2015.)