bluuebunny/crossref_metadata_2025 huggingface dataset:
Vertical gradient in bryophyte diversity and species composition in tropical and subtropical forests in Yunnan, SW China
Authors: Shen Ting , Corlett Richard T. , Song Liang , Ma Wen‐Zhang , Guo Xin‐Lei , Song Yu , Wu Yi
Published: October 2018

Questions

We sampled epiphytic bryophytes along the entire vertical gradient, from tree base to upper canopy, in tropical and subtropical forests in order to answer the following questions: (a) how do diversity, composition and life forms differ between forests; (b) how do communities change along the vertical gradient in each forest; (c) what are the likely environmental drivers of this; and (d) what is the conservation significance of the results?

Location

Canopy crane sites in tropical lowland seasonal rain forest (TRF) and subtropical montane moist forest (STF) in Yunnan, southwest China.

Methods

Bryophytes were sampled from 1,600–2,400 cm2 of bark surface in 14 vertical segments in three canopy layers on 142 trees, using canopy cranes. Microclimate was measured at five levels on the crane towers. Diversity was compared within and between forests using ANOVA. NMDS was used to compare species composition and assess potential drivers.

Results

In total, 184 species were recorded in 106 genera and 39 families. STF had a richer bryoflora than TRF. More species occurred in the canopy than the sub‐canopy and understorey in both sites. The fan life form was dominant in the lower two layers of both forests, while mats were more common in the canopy of TRF and tall turfs in STF. The main axis of variation in species composition was associated with the vertical gradient of declining humidity and vapour pressure, and increasing temperature, light and wind speed.

Conclusions

This study demonstrates the value of canopy cranes for complete sampling of the epiphytic bryoflora in complex forests. Both forest types had very high species richness, reflecting the diversity of microhabitats along the vertical gradient. Observed and projected climate change may threaten this bryoflora as a result of rising temperatures and, in some areas, declining rainfall and fog frequency.
Microclimate and demography interact to shape stable population dynamics across the range of an alpine plant
Authors: Oldfather Meagan F. , Ackerly David D.
Published: October 2018

Heterogeneous terrain in montane systems results in a decoupling of climatic gradients. Population dynamics across species’ ranges in these heterogeneous landscapes are shaped by relationships between demographic rates and these interwoven climate gradients. Linking demography and climate variables across species’ ranges refines our understanding of the underlying mechanisms of species’ current and future ranges.

We explored the importance of multiple microclimatic gradients in shaping individual demographic rates and population growth rates in 16 populations across the elevational distribution of an alpine plant (Ivesia lycopodioides var. scandularis). Using integral projection modeling, we ask how each rate varies across three microclimate gradients: accumulated degree‐days, growing‐season soil moisture, and days of snow cover.

Range‐wide variation in demographic rates was best explained by the combined influence of multiple microclimatic variables. Different pairs of demographic rates exhibited both similar and inverse responses to the same microclimatic gradient, and the microclimatic effects often varied with plant size. These responses resulted in range‐wide projected population persistence, with no declining populations at either elevational range edge or at the extremes of the microclimate gradients.

The complex relationships between topography, microclimate and demography suggest that populations across a species’ range may have unique demographic pathways to stable population dynamics.
Maternal helminth infections and the shaping of offspring immunity
Authors: Dewals Benjamin G. , Layland Laura E. , Prazeres da Costa Clarissa , Horsnell William G.
Published: October 2018

Helminth infections leave a long‐lasting immunological footprint on their hosts. Clinical studies have provided first evidence that maternal helminth infections can result in an altered immune profile in their offspring which can potentially shape how they respond to conditions throughout life. This can relate to changes in offspring induction of immune responses against other diseases. However, whether these changes result in actual changes in offspring ability to control disease is unclear. Our understanding of which immune mechanisms are altered and how they are changed is limited. In this review, we highlight what we know from human and mouse studies about this important context of helminth exposure. Moreover, we discuss how mechanisms such as antibody transfer, antigen exposure, maternal cell uptake, chimerism and epigenetics are all likely to be functional contributors to the striking changes that are seen in offspring born or nursed by helminth exposed mothers.
Who’s Afraid of Strategic Behavior? Mechanisms for Group Purchasing
Authors: Hezarkhani Behzad , Sošić Greys
Published: October 2018

We study mechanisms to manage group purchasing among a set of buyers of a given product with a concave purchase cost function. The buyers are cost‐sensitive and willing to buy a range of product quantities at different prices. We investigate two types of mechanisms that can be used by a group purchasing organization (GPO): (a) ordering mechanisms where the buyers, without divulging private information, choose their order quantities and pay for them according to a given cost‐sharing rule or a fixed price; and (b) bidding mechanisms where the buyers announce their valuations for different quantities and the GPO determines their purchase quantities and cost‐shares according to pre‐announced schemes. Under the choice of appropriate cost‐sharing rules, we introduce a sequential joint ordering mechanism and a family of ordering strategies under which some buyers’ strategic deviations never worsen other buyers. We propose a class of bidding mechanisms with some desirable properties and show that a Nash equilibrium bid schedule always exists wherein all buyers’ profits are at least as high as those under truthful bidding. In our proposed mechanisms, some buyers’ strategic deviation from truthful bidding can only make the others better off. Thus, buyers need not worry about strategic behavior of their counterparts. We compare the performances of the system under different mechanisms and show the superiority of our proposed bidding mechanism. We show that the profits generated by our proposed bidding mechanisms under the proportional cost‐sharing rule are never dominated by the maximum profits of the first‐best fixed price.
Identification of sperm motility markers in bovine transition protein genes
Authors: Hirenallur Maheshwarappa Yathish , Kumar Subodh , Chaudhary Rajni , Mishra Chinmoy , Ayyar Sivakumar , Kumar Amit , Chauhan Anuj , Ghosh Subrata Kumar , Panigrahi Manjit , Mitra Abhijit
Published: October 2018

Contents

Transition proteins (TNPs) are essential in chromatin condensation during spermiogenesis, and hence, they are the candidate genes for identifying sperm motility markers. Coding and in silico predicted promoter regions of these genes were investigated in crossbred and purebred cattle, and also, their mRNA quantification was done to explore its use as a diagnostic tool of infertility. PCR‐SSCP analysis revealed two band patterns in fragment III of TNP1 and fragment II of TNP2 gene. Sequence analysis revealed a deletion of “G” nucleotide in 3′UTR region of TNP1 and C>T SNP in intronic region of TNP2 gene. Least square analysis of variance did not reveal any significant influence of nucleotide deletion on any sperm motility parameters in both crossbred and purebred cattle. However, C>T SNP had a significant effect on initial progressive motility (p < 0.05) in purebred cattle and post‐thaw motility in overall cattle population. RT‐qPCR analysis did not reveal any significant variation in TNP1 and TNP2 gene expression among poorly motile and good quality spermatozoa of Vrindavani bulls.
Morality of Discontent: The Constitution of Political Establishment in the Swedish Rural Press
Authors: Nilsson Bo , Lundgren Anna Sofia
Published: October 2018

Swedish media regularly indicate that people’s confidence in politicians is low. This distrust in or discontent with politicians is often related to rural politics. This paper focuses on the populist tendencies in the representations of politicians in the Swedish rural press during the parliamentary election year of 2014. A discourse analysis of the press material illustrates three closely related and critical themes; politicians are regarded as being urban centred, as doing anything for power, and as acting in an autocratic manner and misusing their power. The discourse analysis also reveals how the critical press material is linked to a moral geography relating space to a specific moral order. Drawing on theories on rural populism, the article shows how the media’s references to a rural‐based victimhood, and to an alleged inequality between urbanity and rurality, can morally legitimate and bluntly express their contempt for ‘scandalous’ politicians, and they can present their critique as rational and justified.
Esophageal Mycobacterium avium‐intracellulare infection in a bone marrow transplant patient: Case report and literature review
Authors: Hou Rong , Nayak Ravi , Pincus Steven M. , Lai Jinping , Omran Louay M. , Alkaade Samer , Abate Getahun
Published: October 2018

Mycobacterium avium‐intracellulare complex (MAC) is the most common cause of nontuberculous mycobacterial (NTM) disease in humans. We report a case of esophageal MAC disease in a patient who had allogeneic bone marrow transplant for acute lymphoblastic leukemia. Although pulmonary MAC in immunocompromised host is not uncommon, there are only a few cases of NTM‐associated esophageal mass reported. Our report and literature review highlight the importance of considering MAC in the differential diagnosis of dysphagia or odynophagia.
Trajectories of women's physical and psychosocial health following obstetric fistula repair in Uganda: a longitudinal study
Authors: El Ayadi Alison M. , Barageine Justus , Korn Abner , Kakaire Othman , Turan Janet , Obore Susan , Byamugisha Josaphat , Lester Felicia , Nalubwama Hadija , Mwanje Haruna , Tripathi Vandana , Miller Suellen
Published: October 2018

Objectives

To explore trajectories of physical and psychosocial health, and their interrelationship, among women completing fistula repair in Uganda for 1 year post‐surgery.

Methods

We recruited a 60‐woman longitudinal cohort at surgical hospitalisation from Mulago Hospital in Kampala Uganda (Dec 2014–June 2015) and followed them for 1 year. We collected survey data on physical and psychosocial health at surgery and at 3, 6, 9 and 12 months via mobile phone. Fistula characteristics were abstracted from medical records. All participants provided written informed consent. We present univariate analysis and linear regression results.

Results

Across post‐surgical follow‐up, most women reported improvements in physical and psychosocial health, largely within the first 6 months. By 12 months, urinary incontinence had declined from 98% to 33% and general weakness from 33% to 17%, while excellent to good general health rose from 0% to 60%. Reintegration, self‐esteem and quality of life all increased through 6 months and remained stable thereafter. Reported stigma reduced, yet some negative self‐perception remained at 12 months (mean 17.8). Psychosocial health was significantly impacted by the report of physical symptoms; at 12 months, physical symptoms were associated with a 21.9 lower mean reintegration score (95% CI −30.1, −12.4).

Conclusions

Our longitudinal cohort experienced dramatic improvements in physical and psychosocial health after surgery. Continuing fistula‐related symptoms and the substantial differences in psychosocial health by physical symptoms support additional intervention to support women's recovery or more targeted psychosocial support and reintegration services to ensure that those coping with physical or psychosocial challenges are appropriately supported.
The Role of Material Modeling on Strain Range Estimation for Elevated Temperature Cyclic Life Evaluation
Authors: Messner M. C. , Jetter R. I. , Sham T.-L. , Wang Yanli
Published: October 2018

High temperature nuclear reactors operating in the creep regime are designed to withstand numerous cyclic events. Current ASME code rules provide two basic paths for evaluating creep fatigue and ratcheting under these conditions; one based on full inelastic analysis intended to provide a representative stress and strain history and the other based on elastic material models with adjustments of varying complexity to account for inelastic stress and strain redistribution. More recent developments have used elastic-perfectly plastic analysis to bound the effects of cyclic service. However, these methods still rely on the separate evaluation of fatigue and creep damage utilizing a damage interaction diagram. There is a procedure under current development that uses creep-fatigue data from key feature test articles directly without the use of the damage interaction diagram. However, it requires a reasonable representation of the strain range in a structure as an input. This work develops a simplified procedure based on elastic perfectly-plasticity analysis that can be used to represent the strain range in a structure in the steady state under cyclic loading conditions.
Establishing Temperature Upper Limits for the ASME Section III, Division 5 Design by Elastic Analysis Methods
Authors: Messner M. C. , Jetter R. I. , Sham T.-L.
Published: October 2018

Section III, Division 5 of the ASME Boiler and Pressure Vessel Code provides two broad paths for the design of high temperature, safety-critical nuclear components: design by elastic analysis and design by inelastic analysis. The design by elastic analysis approach, as the name suggests, uses a linear elastic stress analysis of the component and applies design rules designed to bound response of the actual structure, which will undergo both creep and plasticity. Currently, the Code allows the use of the elastic approach for all operating temperatures up to the maximum use temperatures in the Code. The bounds used in the elastic approach assume an uncoupled material response combining rate dependent creep with rate independent plasticity. However, at elevated temperatures creep and plasticity are coupled, rate dependent mechanisms and so the elastic analysis rules may become non-conservative. We present several examples of potential non-conservatism in the elastic analysis rules at high operating temperatures. Then we describe a systematic method for determining a temperature cutoff describing the transition from non-unified, rate independent plasticity material response to a rate dependent, unified plastic response. Logically, this transition temperature sets the upper bound for the allowable, conservative use of the design by elastic analysis approach and so we propose these temperatures, determined for all the Section III, Division 5 Class A materials, as Code limits for the applicability of the elastic approach.
Application of T-Scaling Method to Account for the Effects of Notch Acuity on Notch Fracture Toughness in the Ductile-to-Brittle Transition Temperature Region
Authors: Nakano Hiroki , Meshii Toshiyuki
Published: October 2018

Current defect assessment procedures based on fracture mechanics usually assume flaws to be infinitely sharp. While this assumption may be appropriate for fatigue cracks, for non-sharp flaws such as porosity, mechanical damage, or weld undercut, it can be an over-conservative assumption that can lead to pessimistic assessments of structural integrity and a significant underestimation of the true safety margin against fracture. Irwin studied notched and pre-cracked fracture toughness in the lower shelf region and suggested that notched KIc, which is linear-elastic plane-strain fracture toughness is proportional to the square root of notch radius ρ but is not continuous with pre-cracked KIc (i.e., when zero is substituted by ρ in the fitted KIc and ρ relationship, the obtained value differs from that of the pre-cracked specimen KIc). In contrast, Begley et al. conducted a similar study in the upper shelf region and suggested that JIc ∝ ρ In addition, they showed that notched JIc is continuous with pre-cracked JIc. Very few studies have been conducted on this topic in the ductile-to-brittle transition temperature (DBTT) region. In this study, the effects of notch acuity on notch fracture toughness in the lower shelf and DBTT regions were studied for 0.55% C steel JIS S55C with 0.5TSE(B) specimens. The notch sizes ρ were selected as 50, 150, and 375 μm. Fatigue pre-cracked specimens were also studied. The experimental results showed that notched KIc ∝ ρ1/2 but is not continuous with the pre-cracked KIc at a lower shelf temperature of −166 °C. The DBTT notch fracture toughness KJc ∝ ρ1/2 and is continuous with the pre-cracked KJc. By conducting elastic-plastic finite element analysis (EP-FEA), the mid-plane crack-opening stress distribution on the x1-axis, was shown that the scaled stress distribution at fracture load was identical for pre-cracked and notched specimens. Thus, notched and pre-cracked KJc has a reason to be continuous. The reason for notch size effect on Jc was explained as the difference in load for notched specimens to reach the stress level of the pre-cracked specimen.
Formulation of the Stress Corrosion Crack Growth Rates for the Practical Use in the Integrity Assessment of Nuclear Reactor Components
Authors: Koshiishi Masato , Aoike Satoru , Hashimoto Tsuneyuki , Hideki Yuya
Published: October 2018

The Hashimoto-Koshiishi model was simplified from a mathematical viewpoint taking into consideration explicit crack growth rate (CGR) dependency on the stress intensity factor to enable practicable use of the model in the integrity assessment of boiling water reactor components. Then simplified equations were developed for different strain distribution cases in the model. The developed simplified equations were applied to analyze CGRs of cold worked stainless steels and the simulated weld heat affected zone of the primary loop recirculation piping and core shroud and these equations reproduced CGRs well.
Research on Creep Analysis of Alloy 617 in AUSC Turbine Components
Authors: Hu Yifeng , Sun Lingen , Chen Gang
Published: October 2018

With the increasing demand of environmental protection, the development of highest efficiency fossil power plants to reduce the CO2 emissions has become a top priority. So the live steam parameters of AUSC unit will be increased to 700°C and 350bar. To achieve the desired operating hours at this temperature the application of nickel base materials is necessary for the main components such as rotors, inner casings and valves. Alloy 617 is selected for forged component.

The creep behavior of Alloy 617 is quite different from Cr steel’s, the design experience of USC units can’t be completely adopted in the AUSC unit. The work presented in this paper, aims to predict the creep strain of Alloy 617 in AUSC turbine components. Several material models for creep in Alloy are compared. Base on the notched specimens’ experimental results, the models of the tertiary creep stage and the multiaxial behavior of turbine component are discussed.
An Introduction to the New ASME Standards on Nonmetallic Pressure Piping Systems
Authors: Henley Charles L. , Eisenman Jeffrey D.
Published: October 2018

Design requirements for nonmetallic piping systems are significantly different from those applicable to piping made of steel and other metals, and the development of rules for nonmetallic materials requires a unique set of expertise. While other piping standards have tried to address the use of nonmetallic materials in industrial piping, they do not provide adequate requirements to cover the service limitations, design, materials, fabrication, installation, fusing or joining, and quality control which are unique to nonmetallic piping systems.

To address this gap, ASME assembled the Committee on Nonmetallic Pressure Piping Systems (NPPS) in 2011 to develop standard rules for the construction of nonmetallic pressure piping systems. Over the last 7 years, the NPPS Committee has developed three new standards which are scheduled to be published in 2018: ASME NM.1 Standard on Thermoplastic Piping, ASME NM.2 Standard on Glass Fiber Reinforced Thermosetting Resin Piping, and ASME NM.3 Standard on Nonmetallic Materials. These standards cover the design, manufacture, fabrication, installation, examination, testing, and inspection of thermoplastic and glass fiber reinforced thermosetting resin piping systems suitable for pressure applications. They will also cover specifications for nonmetallic materials for piping components including material design values and limits on the use of nonmetallic materials.
Evaluation of Risk From Carbon Macro-Segregation in Large Pressure Retaining Forged Nuclear Components
Authors: Gamble Ronald , Hardin Timothy
Published: October 2018

Regions of higher-than-normal carbon content due to carbon macro-segregation have been found in large, pressure retaining forged ferritic steel components in some nuclear reactors. Higher carbon content in ferritic steel can decrease the resistance to fracture from the presence of flaws in the material. Acceptable margins against failure of pressurized components in nuclear safety systems must be maintained throughout their service life to ensure core integrity for all operational and postulated transient loading events. Should carbon macro-segregation substantially reduce the material resistance to fracture in safety components, then the margins against through-wall flaw propagation may fall below those specified by regulatory requirements to ensure adequate component and reactor core integrity.

Probabilistic fracture mechanics (PFM) analyses were performed to assess the risk and structural significance of postulated carbon macro-segregation in large, forged pressure retaining components in pressurized water reactors (PWRs). The risk assessment was performed to evaluate several forged components and two classes of loading events. The forged components include the ring and head forgings in the reactor pressure vessel (RPV), steam generator (S/G) and pressurizer. The loading events used in the risk evaluation include pressurized thermal shock (PTS) transient events and a normal RPV cooldown event. The analyses included a range of component dimensions, surface and embedded flaw distributions, various levels of carbon macro-segregation up to and beyond the maximum measured values for the components, and the effects of neutron irradiation, including the effects of potential copper and phosphorus co-segregation. The PFM analyses were performed using the software, Fracture Analysis of Vessels, Oak Ridge (FAVOR).

The results from the risk assessment indicate that: acceptable margins against failure are maintained through an 80-year operating interval even if carbon macro-segregation were to be present in RPV, S/G and pressurizer ring and head forgings in PWRs; and the risk associated with the presence of carbon macro-segregation in PWR ring and head forgings is significantly lower than regulatory risk related acceptance criteria.
Initial Developments for LBB Application to HTHA Sensitive Non-Stress Relieved Carbon Steel Girth Welds in Refinery Plants
Authors: Wilkowski G. , Hioe Y. , Kurth E. , Punch E. , Uddin M. , Brust F. , Bagnoli K. , Pioszak G.
Published: October 2018

Leak-Before-Break (LBB) has been applied in various industries for decades, and this paper explores using it for a new application. In the refining industry, various process units contain hydrogen at elevated temperatures where high temperature hydrogen attack (HTHA) can occur. This mechanism involves the reaction between hydrogen and carbides to form methane, but also the diffusion of hydrogen occurs in the steel. Under certain temperature and hydrogen partial pressures, the methane formation can cause grain boundary cavitation which leads to fissuring and eventually macroscopic cracking. Generally one designs to avoid such cracking from occurring following the so-called “Nelson Curves” contained in API RP 941; however, in recent years it has been found that non-stress relieved carbon steels are susceptible to HTHA below the original API 941 curve. As a result, the refining industry has experienced a number of leaks in piping and vessels. This paper presents some developmental efforts to apply LBB to non-stress relieved seamless carbon steel piping girth welds susceptible to (HTHA) cracking in refinery applications. Much of this approach builds on analyses, results, and experience from the commercial nuclear industry LBB efforts over the last 30 years. This paper will discuss the results of both mechanical testing as well as detailed modelling efforts to evaluate LBB technology to this new application for circumferential cracks, which to date implies that LBB may be applicable to seamless pipe girth welds. Cracks in tees or other components were not addressed in this work. Axial cracks in seam welds are not addressed in this work.
Comparison of Wall-Temperatures of Two Types of Large Capacity Cylinders for Tube Trailers During CNG Loading Processes
Authors: Deng Guide , Chen Yanhui , Jia Guodong , Gao Zhaojiang , Bo Ke
Published: October 2018

Tube trailers with large capacity gas cylinders have been widely used to deliver compressed natural gas (CNG) in China in recent years. Most of the large capacity cylinders are full steel cylinders (Type CNG-1), and the tube trailers with large capacity glass fiber hoop-wrapped composite cylinders with steel liners (Type CNG-2) have entered into Chinese market since 2011. The tube trailers with CNG-2 cylinders can carry more gases than those with CNG-1 cylinders, but need more loading and cooling time to control their wall-temperatures according to the experiences of on-site operators in gas stations. In this paper, the wall-temperatures of those two types of large capacity cylinders on two tube trailers have been tested using a thermal infrared imaging camera during CNG loading processes in two natural gas stations in China. And numerical simulation on the CNG loading processes has been carried out to investigate the temperature changes of the gases and the shells of the cylinders. The results show that CNG-2 cylinders can have less maximum temperatures of the gases and the shells and less wall-temperature increments at the cost of lower loading rate and longer loading time.
Comparisons of Testing Methods for High-Pressure Hydrogen Storage Container Under the Law and Regulation System of UN and EU
Authors: Yang Bo , Yao Jian-ping , Yuan Yi-wen , Wang Jie-lu , Qian Yao-zhou , Tang Xiao-ying
Published: October 2018

Hydrogen energy as the cleanest fuel to replace gasoline has been accepted by society, hydrogen fuel could be promoted based on the safety of hydrogen-fuel storage containers. For risk-controlling of hydrogen storage containers, there are many laws and regulations in UN and EU set the strict technical requirements on high pressure hydrogen storage systems and require a lot of rigorous experimental verification should be performed before mass production. Frame of GTR No.13, ECER No.134 and EU No406/2010 and the content relevant with high-pressure hydrogen storage container would be discussed emphatically in this paper. Rigorous testing methods in regulations and standards are compared and comments on hydrogen storage container performance testing are provided, besides, some important testing items are discussed.
Limit Load Solution of Non-Aligned Multiple Flaws
Authors: Iwamatsu Fuminori , Miyazaki Katsumasa , Saito Koichi
Published: October 2018

Limit load solutions have been applied to estimate the collapse load of a component made of ductile material. Worldwide maintenance codes for power plants, such as ASME Boiler and Pressure Vessels Code, Section XI, and JSME fitness-for-service code, describe limit load solutions under the assumption of a single flaw. Detected flaws are, however, not always a single flaw, and adjacent flaws due to stress corrosion cracking have been detected in power plants. Thus, development of a limit load solution to estimate the collapse load in the case of multiple flaws remains an issue of structural integrity evaluation. Under the aim of developing a method for evaluating the effect of multiple flaws on collapse load as a part of a limit load solution, fracture tests of flat plates and pipes with multiple flaws were conducted. Although experimental approaches have been attempted to establish the evaluation method, further efforts are required to incorporate the evaluation procedure into a code rule.

Effective parameters for considering reduction of collapse load on the basis of test results for specimens with multiple flaws were identified. Test results clearly show a correlation between collapse load and ratios of net-section areas. This correlation leads to the conclusion that distance parameters and flaw length of a smaller flaw determine the existence of an effect on the collapse load by multiple flaws. To investigate the physical sense of the correlation, finite element analysis (FEA) was performed. The FEA results show that strain distributions at the flaw tip under several conditions correspond at the time of maximum load of the fracture tests regardless of the effect of multiple flaws. Also according to the FEA results, the extent of the strain field is linearly proportional to flaw length. These FEA results are consistent with the correlation obtained by the test results.
A Residual Stress Profile Estimation Method for Narrow Groove Girth Welds
Authors: Song Shaopin , Dong Pingsha
Published: October 2018

A recent comprehensive investigation into residual stress distributions in narrow gap welds in pressure vessels and pipe components are presented in this paper, covering component wall thickness from 1” (25.4mm) to 10” (254mm), component radius to wall thickness ratio from 2 to 100, and linear welding heating input from low (300 J/mm) to high (18000 J/mm). By means of a residual stress decomposition technique, two key parameters that govern through-thickness residual stress distributions in terms of their membrane and bending content have been identified. One is component radius to wall thickness ratio (r/t) and the other is a characteristic heat input density (Q̂) having a unit of J/mm3. With these two parameters, a unified functional form for representing through-thickness residual stress profile in narrow gap welds is proposed for supporting fitness for service assessment, e.g., using f API 579-RP. Its validity is further confirmed by full-blown thermomechanical finite element residual stress analyses for a number of selected narrow gap weld cases.
ASME B16.20 Jacketed Gaskets Performance Testing
Authors: Baulch Joel , Girão Carlos D. , Veiga José , Hamilton Scott
Published: October 2018

Jacketed gaskets have widespread use in the industry. The current revision of ASME B16.20-2017 provides several details of jacketed gasket construction and dimensions for use on ASME B16.5 or ASME B16.47 flanges. However, it does not currently provide a testing protocol to evaluate the sealing performance of this gasket style. This paper reports sealability and compression results with distinct sizes of jacketed gaskets tested based on the protocol proposed in ASME B16.20 - Spiral Wound Gaskets Performance Testing.
Mechanical Design of Electrical Isolation Joint
Authors: Ricco Giovanni
Published: October 2018

The Electrical Isolation Joint is considered a pressure vessel and is usually designed according to ASME VIII Div.1, but the code does not provide specific rules for the component. This paper provides the mechanical design of an Electrical Insulation Joint according to ASME VIII div.1, Appendix 2, “Rules for Bolted Flange.” The scope of this work is to suggest design guidelines to be included in the ASME VIII Div.1 code for Electrical Isolation Joints.

The first part of the paper will introduce the geometry of typical electrical isolation joint and will show the distribution of stresses due to internal pressure.

The second part of this work will introduce the design of the isolation Joint size of 24” nominal diameter as per ASME VIII div.1 Appendix 2 for items subjected to internal pressure.

The third part will compare design results above described with Finite Element Analysis as per ASME VIII div.2 part 5 for design validation.
Retracted: “Comparison of Different Bolt Elongation Load Control Methods” [ASME 2018 Pressure Vessels and Piping Conference, Volume 3A: Design and Analysis, Prague, Czech Republic, July 15–20, 2018, Conference Sponsors: Pressure Vessels and Piping Division, ISBN: 978-0-7918-5162-3, Copyright © 2018 by ASME. Paper No. PVP2018-85004, pp. V03AT03A017; 16 pages; doi:10.1115/PVP2018-85004]
Authors: ASME
Published: October 2018

This paper has been retracted by the American Society of Mechanical Engineers due the commercial nature of the content. December 21, 2018.

Copyright © 2018 by ASME
Bolted Flange Joint Assembly Service Provider Assessments
Authors: Thibodeaux Brett , Hamilton Scott
Published: October 2018

There have been two major updates to ASME PCC-1 “Guidelines for Pressure Boundary Bolted Flange Joint Assembly” within the past 7 years. In 2010, substantial technical information was added, and in 2013 Appendix A “Training and Qualification of Bolted Joint Assembly Personnel” was added to the document. This paper provides an overview of a program to review and evaluate bolting contractors that serve the refining and chemical process industries, based on their level of alignment with the requirements of ASME PCC-1 Appendix A, and describes a method of applying the results using a risk-based approach.
Cortical markers of auditory stream segregation revealed for streaming based on tonotopy but not pitch
Authors: Ruggles Dorea R. , Tausend Alexis N. , Shamma Shihab A. , Oxenham Andrew J.
Published: October 2018

The brain decomposes mixtures of sounds, such as competing talkers, into perceptual streams that can be attended to individually. Attention can enhance the cortical representation of streams, but it is unknown what acoustic features the enhancement reflects, or where in the auditory pathways attentional enhancement is first observed. Here, behavioral measures of streaming were combined with simultaneous low- and high-frequency envelope-following responses (EFR) that are thought to originate primarily from cortical and subcortical regions, respectively. Repeating triplets of harmonic complex tones were presented with alternating fundamental frequencies. The tones were filtered to contain either low-numbered spectrally resolved harmonics, or only high-numbered unresolved harmonics. The behavioral results confirmed that segregation can be based on either tonotopic or pitch cues. The EFR results revealed no effects of streaming or attention on subcortical responses. Cortical responses revealed attentional enhancement under conditions of streaming, but only when tonotopic cues were available, not when streaming was based only on pitch cues. The results suggest that the attentional modulation of phase-locked responses is dominated by tonotopically tuned cortical neurons that are insensitive to pitch or periodicity cues.
Electrochemically induced phase separation and in situ formation of mesoporous structures in ionic liquid mixtures
Authors: Lahiri Abhishek , Behrens Niklas , Pulletikurthi Giridhar , Yochelis Arik , Kroke Edwin , Cui Tong , Endres Frank
Published: October 2018

Tailoring mesoporous structures via electrochemically induced phase separation at solid/ionic-liquid interface is shown.
Genomic Characterization of Cyanophage vB_AphaS-CL131 Infecting Filamentous Diazotrophic Cyanobacterium
Aphanizomenon flos-aquae
Reveals Novel Insights into Virus-Bacterium Interactions
Authors: Šulčius Sigitas , Šimoliūnas Eugenijus , Alzbutas Gediminas , Gasiūnas Giedrius , Jauniškis Vykintas , Kuznecova Jolita , Miettinen Sini , Nilsson Emelie , Meškys Rolandas , Roine Elina , Paškauskas Ričardas , Holmfeldt Karin
Published: October 2018

The genomic characterization of novel cyanophage vB_AphaS-CL131 and the analysis of its genomic features in the context of other viruses, metagenomic data, and host CRISPR-Cas systems contribute toward a better understanding of aquatic viral diversity and distribution in general and of brackish-water cyanophages infecting filamentous diazotrophic cyanobacteria in the Baltic Sea in particular. The results of this study revealed previously undescribed features of cyanophage genomes (e.g., self-excising intein-containing putative dCTP deaminase and putative cyanophage-encoded CRISPR-Cas and toxin-antitoxin systems) and can therefore be used to predict potential interactions between bloom-forming cyanobacteria and their cyanophages.
A Secreted Bacterial Peptidylarginine Deiminase Can Neutralize Human Innate Immune Defenses
Authors: Stobernack Tim , du Teil Espina Marines , Mulder Lianne M. , Palma Medina Laura M. , Piebenga Dillon R. , Gabarrini Giorgio , Zhao Xin , Janssen Koen M. J. , Hulzebos Jarnick , Brouwer Elisabeth , Sura Thomas , Becher Dörte , van Winkelhoff Arie Jan , Götz Friedrich , Otto Andreas , Westra Johanna , van Dijl Jan Maarten
Published: October 2018

Bacterial pathogens do not only succeed in breaking the barriers that protect humans from infection, but they also manage to evade insults from the human immune system. The importance of the present study resides in the fact that protein citrullination is shown to represent a new bacterial mechanism for immune evasion. In particular, the oral pathogen
P. gingivalis
employs this mechanism to defuse innate immune responses by secreting a protein-citrullinating enzyme. Of note, this finding impacts not only the global health problem of periodontitis, but it also extends to the prevalent autoimmune disease rheumatoid arthritis, which has been strongly associated with periodontitis, PPAD activity, and loss of tolerance against citrullinated proteins, such as the histone H3.
Structural and Nonstructural Genes Contribute to the Genetic Diversity of RNA Viruses
Authors: Collins Natalie D. , Beck Andrew S. , Widen Steven G. , Wood Thomas G. , Higgs Stephen , Barrett Alan D. T.
Published: October 2018

With the advent of advanced sequencing technology, studies of RNA viruses have shown that genetic diversity can contribute to both attenuation and virulence and the paradigm is that this is controlled by the error-prone RNA-dependent RNA polymerase (RdRp). Since wild-type yellow fever virus (YFV) strain Asibi has genetic diversity typical of a wild-type RNA virus, while 17D virus vaccine has limited diversity, it provides a unique opportunity to investigate RNA population theory in the context of a well-characterized live attenuated vaccine. Utilizing infectious clone-derived viruses, we show that genetic diversity of RNA viruses is complex and that multiple genes, including structural genes and NS2B and NS4B genes also contribute to genetic diversity. We suggest that the replication complex as a whole, rather than only RdRp, drives genetic diversity, at least for YFV.
Functional Assessment of 2,177 U.S. and International Drugs Identifies the Quinoline Nitroxoline as a Potent Amoebicidal Agent against the Pathogen
Balamuthia mandrillaris
Authors: Laurie Matthew T. , White Corin V. , Retallack Hanna , Wu Wesley , Moser Matthew S. , Sakanari Judy A. , Ang Kenny , Wilson Christopher , Arkin Michelle R. , DeRisi Joseph L.
Published: October 2018

Balamuthia mandrillaris
is responsible for hundreds of reported cases of amoebic encephalitis, the majority of which have been fatal. Despite being an exceptionally deadly pathogen,
B. mandrillaris
is understudied, leaving many open questions regarding epidemiology, diagnosis, and treatment. Due to the lack of effective drugs to fight
B. mandrillaris
infections, mortality rates remain high even for patients receiving intensive care. This report addresses the need for new treatment options through a drug repurposing screen to identify novel
B. mandrillaris
inhibitors. The most promising candidate identified was the quinoline antibiotic nitroxoline, which has a long history of safe use in humans. We show that nitroxoline kills
B. mandrillaris
at pharmacologically relevant concentrations and exhibits greater potency and selectivity than drugs commonly used in the current standard of care. The findings that we present demonstrate the potential of nitroxoline to be an important new tool in the treatment of life-threatening
B. mandrillaris
infections.
Infection of a tophaceous nodule of the wirst and hand
Authors: Bouaziz Wajdi , Rekik Mohamed Ali , Guidara Ahmed Racem , Keskes Hassib
Published: October 2018

Tophaceous gout occurs years after recurrent attacks of acute inflammatory arthritis. The urate deposits are incriminated in the inflammatory process; however, their infection is exceptional. We report the observation of an infected gouty tophus of the pinky and the wrist of a 40-year-old man, presented as an excruciating inflammatory pain with buff-yellow swelling of the fifth right finger and wrist in a febrile context. As a matter of fact, the evolution was favourable after surgical excision and antibiotic therapy. The infection of a tophus is an exceptional complication of the gout. In daily practice, this diagnosis is really a difficult challenge for the clinician. The systematic bacteriological examination of the tophi with cutaneous fistulation is necessary to introduce prematurely an adapted treatment.
Molecular diagnosis of inherited peripheral neuropathies by targeted next-generation sequencing: molecular spectrum delineation
Authors: Bacquet Juliette , Stojkovic Tanya , Boyer Amandine , Martini Nathalie , Audic Frédérique , Chabrol Brigitte , Salort-Campana Emmanuelle , Delmont Emilien , Desvignes Jean-Pierre , Verschueren Annie , Attarian Shahram , Chaussenot Annabelle , Delague Valérie , Levy Nicolas , Bonello-Palot Nathalie
Published: October 2018

Purpose

Inherited peripheral neuropathies (IPN) represent a large heterogenous group of hereditary diseases with more than 100 causative genes reported to date. In this context, targeted next-generation sequencing (NGS) offers the opportunity to screen all these genes with high efficiency in order to unravel the genetic basis of the disease. Here, we compare the diagnostic yield of targeted NGS with our previous gene by gene Sanger sequencing strategy. We also describe several novel likely pathogenic variants.

Design and participants

We have completed the targeted NGS of 81 IPN genes in a cohort of 123 unrelated patients affected with diverse forms of IPNs, mostly Charcot-Marie-Tooth disease (CMT): 23% CMT1, 52% CMT2, 9% distal hereditary motor neuropathy, 7% hereditary sensory and autonomic neuropathy and 6.5% intermediate CMT.

Results

We have solved the molecular diagnosis in 49 of 123 patients (~40%). Among the identified variants, 26 variants were already reported in the literature. In our cohort, the most frequently mutated genes are respectively:MFN2,SH3TC2,GDAP1,NEFL,GAN,KIF5AandAARS. Panel-based NGS was more efficient in familial cases than in sporadic cases (diagnostic yield 49%vs19%, respectively). NGS-based search for copy number variations, allowed the identification of three duplications in three patients and raised the diagnostic yield to 41%. This yield is two times higher than the one obtained previously by gene Sanger sequencing screening. The impact of panel-based NGS screening is particularly important for demyelinating CMT (CMT1) subtypes, for which the success rate reached 87% (36% only for axonal CMT2).

Conclusion

NGS allowed to identify causal mutations in a shorter and cost-effective time. Actually, targeted NGS is a well-suited strategy for efficient molecular diagnosis of IPNs. However, NGS leads to the identification of numerous variants of unknown significance, which interpretation requires interdisciplinary collaborations between molecular geneticists, clinicians and (neuro)pathologists.
Evolution of transcatheter aortic valve implantation over 7 years: results of a prospective single-centre registry of 2000 patients in a large municipal hospital (TAVIK Registry)
Authors: Schymik Gerhard , Herzberger Valentin , Bergmann Jens , Bramlage Peter , Conzelmann Lars O , Würth Alexander , Luik Armin , Schröfel Holger , Tzamalis Panagiotis
Published: October 2018

Objectives

Use of transcatheter aortic valve implantation (TAVI) to treat severe aortic stenosis (AS) has gained popularity, accompanied by an evolution of patient and clinical factors. We aimed to characterise changes and evaluate their impact on outcomes.

Setting

In this single-centre, German TAVIK registry patients undergoing TAVI between 2008 and 2015 were documented prospectively.

Participants/interventions

2000 consecutive patients with AS undergoing TAVI were divided in four cohorts. 500 patients underwent TAVI in each of the following time bins: April 2008 to July 2010 (cohort I), July 2010 to April 2013 (cohort II), April 2012 to October 2013 (cohort III) and October 2013 to March 2015 (cohort IV).

Results

The mean age was 81.8 years, without significant variation across cohorts. Compared with cohort I, prior MI (5.4%vs11.0%; p<0.001) and New York Heart Association class IV (10.0%vs3.6%; p<0.001) were less common in cohort IV. Across cohorts, there was a fall in EuroSCORE (24.3%–18.7%), frailty (48.4%–17.0%) and use of transapical access (43.6%–29.0%), while transfemoral access increased (56.4%–71.0%; p<0.001 for each). Periprocedurally, there was a fall in moderate/severe aortic regurgitation (3.2%–0.0%) and rate of unplanned cardiopulmonary bypass (4.0%–1.0%; both p<0.001). A similar trend applied to 30-day rate of major vascular complications (5.2%–1.8%; p=0.006), life-threatening bleeding (7.0%–3.0%; p<0.001) and cardiovascular mortality (4.4%–1.8%; p=0.020). One-year post-TAVI, mortality and stroke rates did not differ.

Conclusions

Evolution of TAVI between 2008 and 2015 saw a trend towards its usage in lower risk patients and rapid progression towards improved safety. Evaluation and refinement should now continue to further lessen stroke and pacemaker rates.