bluuebunny/crossref_metadata_2025 huggingface dataset:
Cooldown of LNG Loading Systems – An Integrated Approach. Part 1: Piping Stress Analysis
Authors: Bottomley Ian , Carr Nick , Nicolle Andre , Azarbadegan Alireza
Published: November 2024

A common understanding amongst designers and operators of LNG terminals is that cooling down large-bore stainless steel piping systems using Liquid Natural Gas (LNG) or Liquid Nitrogen (LN2) can lead to steep temperature gradients generating high stresses / strains and the potential for low-cycle fatigue failure.

The normal approach for cooling down LNG piping systems is that they are cooled down over a long period of time during the commissioning or Start-up phase and then kept cold through continuous recirculation of the LNG to minimize or avoid the need to cooldown again during normal operation. The slow cooldown approach is typically achieved by using a sufficient volume of boil-off gas generated from LNG or LN2. Cold gas ensures uniform cooldown of large-bore stainless steel piping systems to avoid excessive thermal stresses. However, using boil-off gas for the slow cooldown of LNG loading systems is not practical in all facilities, particularly in substantial piping systems with significant thermal mass where generating sufficient volumes of cold gas is impractical.

This paper presents the first part of a comprehensive study on a hybrid cooldown approach using liquid and boil-off gas to cool the LNG piping system. A multiphysics approach is adopted which includes CFD analysis to model the heat transfer from the liquid and gas to the pipe. The temperature gradients developed are then mapped to an FEA of the piping system to evaluate the impact of circumferential temperature gradient on local and global thermal stresses and thereby determine the fatigue life of the system.

This paper is Part 1 of a series of papers. This paper focusses on the results of investigations carried out to better understand the theory of how the temperature gradients and stresses will develop in a piping system and their sensitivity to the rate at which the cryogenic liquid enters the pipework. From this a strategy is developed which will ultimately provide the basis for a cooldown procedure.

Subsequent papers will cover the application of the cooldown procedure to the actual piping system. This will include a full CFD and FEA of the piping system combined with validation of the simulation from the commissioning of the live system. It is anticipated that Part 2 will be published in 2025.
Very Low Cycle Fatigue Evaluation of Pipe Elbow Under Dynamic Cyclic Loading and Experimental Validations
Authors: Song Hyun-Seok , Park Joo-Young , Kim Yun-Jae , Kim Jin-Weon
Published: November 2024

This paper reports the strain-based very low cycle fatigue evaluation results of SA403 WP316 stainless steel pipe elbow under dynamic cyclic loading condition. Very low cycle fatigue tests of a pipe elbow under dynamic cyclic loading were performed. A sine wave acceleration was applied to repeat opening and closing of the pipe elbow, and the internal pressure was applied or not applied depending on the test. Failure occurred by very low cycle fatigue crack inside the crown of the pipe elbow. The tests were simulated by finite element dynamic analysis using Rayleigh damping with 0.5% damping ratio and bi-linear kinematic hardening model of which parameters were determined by JSME Code Case rule. The simulation was validated by comparing the acceleration of the mass attached at one end of the pipe elbow specimen and the displacement between each end of the elbow specimen with experimental data. Using the simulation data, the very low cycle fatigue evaluation of pipe elbow under dynamic cyclic loading was performed to calculate the cumulative usage factor. In the evaluation, two strain-based evaluation methods were used: (1) ASME BPVC Sec. VIII Div. 2 Part 5 and (2) the model incorporating the void shrinkage effect. The method incorporating the void shrinkage effect significantly improves the evaluation results and still gives conservative results. Above conclusions are consistent with the findings for quasi-static cyclic loading.
Experimental Study on Mechanical Response of Defective Gas Pipeline Under Heavy Vehicle Load
Authors: Ren Fei , Shuai Yi , Lv Zhiyang , Mei Yuan , Xie Dong , Jiang Lu , Jiang Lumeng , Yu Shengyang
Published: November 2024

Pipeline is one of the infrastructure that ensures people’s livelihood and social production. With the acceleration of urbanization, the impact of vehicle overload on the safety of buried pipelines is becoming increasingly serious. Especially for buried defective gas pipelines with a long service life, when the pipeline ruptures due to vehicle loading, it can cause serious fire and explosion accidents, seriously affecting the safety of urban areas. Experimental study on mechanical response of defective gas pipeline under heavy vehicle load is carried out in the paper. The considered pipeline defect conditions include defect size and defect location. Based on the research results, it can be found that under vehicle overload conditions, the deformation variables of pipeline end defects are significantly lower than those in the middle. As the axial length of the defect increases, the strain at the defect site of the pipeline can decrease to a certain extent. Pipeline strain is more sensitive to defect size than defect location, and defect size may be a high-risk point for pipeline failure under heavy load conditions. There is consistency between the overall deformation of the pipeline and the strain test results. Pipeline deformation is more sensitive to defect size than defect location, but its overall characterization ability is not as good as the strain parameters at the defect location.
EPRG Full Scale Fatigue Crack Growth Test on a Modern Linepipe Material in Gaseous Hydrogen
Authors: Bezensek Bostjan , Huising Otto Jan , Bacchi Luca , Roovers Paul , Bertelli Emanuele
Published: November 2024

EPRG (European Pipeline Research Group) is performing full scale fatigue crack growth testing in high purity hydrogen gas on a 28” OD API5L X70 modern LSAW welded pipe. The test vessel also contains normal (250 HV10) and high hardness (300 HV10) girth welds. The vessel is seeded with EDM notches and weld flaws. The aims of the test are to assess the effect of hardness on fatigue crack growth and fracture, compare the small scale laboratory testing with full scale behaviour under cyclic pressure and compare the modern with vintage materials.

In the ongoing modern pipe test several notches have established fatigue crack growth and some have reached failure point. An accelerated fatigue crack growth was observed consistent with small scale test results and the recent HyBlend fatigue crack growth model. A small non-fatigue driven crack growth is observed under constant pressure following large pressure cycling and this is attributed to both, a transient remnant cyclic plasticity driving force and exceedance of the toughness value Jth (at Δa = 0mm) rather than due to a new subcritical crack growth mechanism (the da/dt effect). Further small scale testing is ongoing to confirm this observation. Design of hydrogen pipelines such that the Jth (at onset of crack growth) is not exceeded should mitigate this concern.
Remaining Useful Creep Life Evaluations of Three Main Steam Piping Systems With Girth Weld Creep Cracks
Authors: Cohn Marvin J.
Published: November 2024

Safety and reliability are the preeminent concerns in the design, operation, and maintenance of power piping systems. Main steam (MS) piping systems in power piping plants are subject to severe operating conditions including creep range temperatures, high pressures, high stresses, cycling, and malfunctioning supports. Over time, these factors lead to material degradation which can significantly reduce the long term integrity and safety of the piping system. The identification and evaluation of critical components is vital to ensuring the efficacy of these piping systems and is useful to make informed maintenance decisions.

Conventional designs of MS piping systems in the United States comply with the American Society of Mechanical Engineers (ASME) B31.1 Power Piping Code. While operating in the creep range, thermal expansion stresses gradually redistribute over time. However, the ASME B31.1 Code does not consider the evaluations of time-dependent thermal stress redistribution, multiaxial stress effects, through-wall stress redistribution, residual welding stresses, and time-dependent creep life consumption due to material creep degradation.

The MS piping system is one of the most critical high energy piping systems. Many of the MS piping system girth weld failures have accelerated creep damage due to a combination of high operating temperatures and unintended high stresses from malfunctioning supports.

Over the past two decades, a creep life consumption methodology has been used to predict material creep damage in MS piping system girth welds considering the most current site information. This methodology has been used to prioritize the most likely girth welds to have accelerated creep damage. Three MS piping systems with service-related girth weld creep cracks are evaluated with a creep life consumption methodology that considers base metal equivalent weld stresses, multiaxial stress factors, time-dependent stress redistribution, cumulative life consumption curves, and illustrations of color-coded piping system (remaining useful life) RUL contour plots. The piping system RUL contour plots provide a visual representation of the girth weld remaining creep lives, which facilitate prioritized inspection decisions.
Technical Basis for Inspection Optimization and Deferral of PWR Pressurizer Component Examinations
Authors: Cofie Nathaniel G. , Dedhia Dilip , Chesworth Scott T. , Shim Do Jun , Grizzi Robert
Published: November 2024

Pressurizer welds in pressurized water reactors (PWRs) are required to be inspected every ten years by ASME Code, Section XI. The results of a comprehensive survey of over forty years of examinations for pressurizer welds performed at 74 domestic and international PWR units showed that no known degradation has occurred in these welds. This demonstrated that pressurizer welds are very flaw tolerant and can accommodate a much longer inspection period. A comprehensive study involving stress analyses and probabilistic and deterministic fracture mechanics analyses supported this observation and determined that the inspection of these welds can be deferred beyond the current ten-year requirement without compromising plant safety. As an alternative to the inspection interval for PWR pressurizer welds provided in Section XI of the ASME Code, EPRI developed the technical basis for deferring these examinations for an extended period in EPRI Report 3002015905.

A Code Case has been introduced in ASME Code, Section XI that would allow the inspection of certain pressurizer weld components to be deferred to 30 years after the date of the last qualified inspection of each component type. Specifically, the Code Case addresses the following ASME Code, Section XI Examination Categories and Item Numbers:

• Class 1, Category B-B, pressure-retaining welds in vessels other than reactor vessels (Item Nos. B2.11, B2.12, B2.21 and B2.22), and

• Class 1, Category B-D, full penetration welded nozzles in vessels (Item No. B3.110).

The technical basis report has been used by at least 20 PWR units (with Salem Units 1 and 2 being the lead plant submittal) to request relief from the U.S. Nuclear Regulatory Commission (NRC) for deferral of these two pressurizer weld examination categories to greater than 10 years.

This paper provides the technical basis for the 30-year deferral of the examination of pressurizer weld components in support of the proposed Code Case using the results of the evaluations in the EPRI technical basis report plus additional evaluations that were performed to specifically address the 30-year deferral period and the lessons learned through the Request for Alternative process by the lead and follow-on plants.
Quantitative Characterization of Hydride Morphology in Support of Improving Cohesive-Zone Fracture Toughness Model for Zr-2.5Nb Pressure Tubes
Authors: Liu Cheng
Published: November 2024

The CSA Standard N285.8 requires evaluation of service conditions for protection against fracture of operating Zr-2.5Nb pressure tubes in CANDU®1 reactors, as well as demonstration of Leak-Before-Break. Zr-2.5Nb pressure tubes are susceptible to hydride formation when the solubility of hydrogen in the pressure tube material is exceeded. Experiments have shown that the presence of hydrides can reduce the fracture toughness of the pressure tubes, depending on hydrogen concentration, hydride distribution and temperature. An improved cohesive-zone based model has been developed to predict the fracture toughness of Zr-2.5Nb pressure tubes in the lower-shelf and transition temperature regimes. To support the model development, quantitative metallography of bulk hydrides has been performed on optical micrographs from metallographic samples taken from hydrided irradiated rising pressure burst test specimens, and from rolled joint regions of ex-service pressure tubes. The results of quantitative metallography have been analyzed statistically to characterize the variations of the hydride morphology and the matrix ligament distribution in the radial-circumferential plane of the pressure tube. Parametric distributions have been developed for bulk hydride length, bulk hydride orientation angle, and radial extent of matrix ligament between bulk hydrides. Engineering relations have been further developed to characterize the variation of the parametric distribution of bulk hydride orientation angle. This paper describes the methodologies used in the quantitative characterization of hydride morphology and discusses the results.
Research on Effects of Surface Finishing and Mean Stress on Fatigue Lives of Notched Specimens - Surface Finishing Effect for Notched Specimens of Low Alloy Steel
Authors: Nomura Yuichiro , Takagoshi Daiki , Asada Seiji , Sugeta Atsushi , Kitamura Yoshihide
Published: November 2024

The DFC and DFC2 subcommittees in the Japan Welding Engineering Society developed a new approach of fatigue analysis method with support from the Japanese utilities. This fatigue analysis method had several modifications made and has been incorporated into the JSME Environmental Fatigue Evaluation Method 2022 Edition (JSME S NF1). Also, research on effects of surface finishing and mean stress on fatigue lives of notched specimens have been conducted by the DFC3 and DFC4. In this paper, the test plan and overview of the outcomes of the DFC3 and DFC4 are introduced.

In this series of research, effects of surface finishing on fatigue strength and relation between a fatigue strength reduction factor and mean stress correction have been investigated using notched specimens, of which materials are carbon steel (CS:JIS STPT370) and low alloy steel (LAS:JIS SQV2A). The applicability of the Ksf (factor for the effect of surface finishing) equation of the JSME S NF1 to notched specimens has been investigated and confirmed based on the experimental results.

The order of consideration of the fatigue strength reduction factor and mean stress correction may not need to be considered if the Smith Watson Topper (SWT) approach can be applied to mean stress correction. Hence, the applicability of the SWT approach with stress concentration and mean stress have been investigated and confirmed based on the experimental results.

In this study, the effect of surface roughness due to emery polishing and machining (Rz = 25μm) was confirmed using circumferentially notched specimens. Ksf(ε) of the circumferentially notched machined condition was almost equal to the surface finish effect coefficient Ksf of the smooth machined material of the same roughness. It was confirmed that the JSME Ksf equation can be applied to the circumferentially notched shape and evaluated on the conservative.
Study of Fatigue Properties of Graphite Materials Under Four-Point Bending
Authors: Zhou Junjie , Wu Tianhao , Sun Libin , Shi Li , Wang Xiaoxin
Published: November 2024

The structural integrity of graphite components, supporting the reactor core of HTGRs (High-Temperature Gas-Cooled Reactor), is essential to the operational safety of the reactor. Therefore, the fatigue performance of graphite structures has been an extremely significant issue in both academia and industry. Currently, the stress amplitudes of the fatigue tests of nuclear graphite are normally less than its tensile strength, which is unsuitable for some components with stress concentrations. In this paper, fatigue tests with four-point bending loading were carried out to investigate the fatigue behavior of the nuclear-grade graphite material IG110 at stress levels higher than tensile strength. The four-point bending fatigue test fixture was designed based on the ASTM test standard. Different samples were tested to study the stress concentration effects. In the test, the bending fatigue life of graphite materials under different stress levels was obtained. The fatigue properties of graphite materials under bending load were also analyzed. This study not only provides important experimental data and theoretical guidance for the engineering application of nuclear-grade graphite materials in HTGRs, but also provides useful experience and inspiration for the fatigue performance studies of other brittle materials.
Full Scale Three-Dimensional Moving Arc Weld Analyses of Control Rod Drive Mechanism J-Groove Welds and Implications on Cracking
Authors: Brust Frederick W. , Punch Ed , Twombly Elizabeth
Published: November 2024

Flaw indications have been found in some nozzle to stainless steel piping dissimilar metal (DM) welds and reactor pressure vessel heads (RPVH) control rod drive mechanism (CRDM) tube welds in pressurized water reactors (PWR) throughout the world. The nozzle and J-groove welds usually involve welding ferritic (often A508) nozzles using Alloy 182/82 weld metal. Many of the nozzles have been repaired by using A152/52 filler metal which is resistant to primary water stress corrosion cracking (PWSCC) but many of the CRDM welds remain A182/82 material. The welds may become susceptible to a form of corrosion cracking referred to as primary water stress corrosion cracking (PWSCC). It can occur if the temperature is high enough (usually > 300C) and the water chemistry in the PWR is typical of operating plants. The weld residual stresses (WRS) induced by the welds are a main driver of PWSCC. Crack growth in the J-groove welds of the vessel heads remains a concern for the integrity of the heads.

Computational weld analyses were performed for nozzles of different angles including 0-degree (top dead center), 25-degree, and 53-degree nozzles years ago. In the past simplified weld analyses of the J-groove welds using a ‘lump pass’ analysis procedure and simple geometric symmetry assumptions of the j-groove welds were made. Here full moving arc solutions of the full J-groove welds are made without the simplified geometric assumptions made in the past. Here FE models were used in this project to perform analyses of a small angle (9-degree) and a large angle (46-degree) nozzle and compared to limited WRS measurements at several locations in similar size head nozzles.

This paper summarizes WRS fields that are developed in the J-groove welds and ramifications on crack growth in the welds. Discussion of crack growth in these heads and consideration of Code Case N-729 assessment of cracking in these welds and tubes is discussed as well.
An Examination of Margins Needed to Ensure Conservative Application of T0 to RPV Fracture Toughness
Authors: Hall J. Brian , Golchert Brian M. , Simpson Derek
Published: November 2024

Variation in fracture toughness of a heavy-section reactor pressure vessel (RPV) steel plate, forging or weld can be caused primarily by processing and chemical composition variation. Understanding the variation is paramount to enable application of the ASTM E1921 measured ductile-brittle transition temperature, T0, to RPV integrity evaluations. Variation in toughness in thick section forgings and plates can be caused by carbon segregation and through thickness by the quenching process. Variation in toughness can also be caused by variation in chemical composition of the elements that enhance irradiation embrittlement, primarily copper and nickel. The geometric scale of these variations varies. For example, carbon segregation in a large ring forging might be limited to one region while it is well documented that toughness increases near the surface where the cooling rate was high when quenching. For welds, copper and nickel might vary within and between weld beads and at least a significant portion of the variation is captured in a typical set of toughness specimens used to determine T0. This paper will look at many datasets where at least two sets of specimen tests from which T0 can be calculated are available from the same heat of steel. It will be assumed that one T0 measurement is used as the direct fracture toughness measurement and the 2nd (or more) are measurements from the irradiated RPV represented by the irradiated ductile-brittle transition temperature fracture toughness test results. One T0 measurement will be adjusted to the condition of the 2nd (or more) measured dataset with assessment of the margin needed to ensure an evaluation of the RPV would be bounding. This information will enable development of necessary margins in applying unirradiated and irradiated master curve fracture toughness measurements to an RPV component using relatively small samples.
Investigation of Fluidelastic Instability in Normal Square Tube Arrays Subjected to Air Flow
Authors: Elhelaly Amro , Hassan Marwan
Published: November 2024

A comprehensive set of wind tunnel experiments was carried out, focusing on the normal square (in-line) array subjected to air cross-flow. The array’s geometric influence, encompassing factors such as array size, type, pitch ratio, and flexibility level, on the stability threshold were investigated. For the first time, experimental observation of streamwise fluidelastic instability (SFEI) in the normal square array was confirmed. The findings highlight the important role played by the array’s pitch ratio and the number of flexible tubes in influencing the stability threshold, specifically in the transverse directions.
Comparison of Cyclic Performance Between Grade 11 and Grade 22 Plate With Application to Coke Drum Bulging
Authors: Dewees Dave
Published: November 2024

Measured cyclic material properties (cyclic stress-strain, fatigue initiation and fatigue crack growth) are collected from the open literature for 2¼Cr-1Mo (Grade 22) and 1¼Cr-½Mo (Grade 11) plate and compared. Basic fatigue resistance (initiation plus growth) is evaluated, as well as cyclic plastic material models for assessing the role of stress and strain evolution for a theoretical coke drum thermal quench event. Transient 3D solid finite element analysis is leveraged to investigate the role of initial plate strength and well as cyclic hardening and softening and conclusions on material performance for bulging and cracking are offered. Cyclic softening is tuned to the experimental stress vs. cycle data from a standard constant strain amplitude fatigue test. A representative (although bounding) thermal cycle is analyzed where an 800°F–300°F (427°C–149°C) temperature differential is suddenly imposed over a given spot on the coke drum inside surface and held until thermal steady state is reached. Even though both plate materials eventually reach similar stabilized cyclic properties after repeated loading and unloading, the initial strength of the materials plays a crucial role in determining their behavior, particularly in terms of bulging. Despite the fact that higher strength materials tend to soften more before reaching stabilized cyclic behavior, it’s found that Grade 22 material, with its stronger starting strength, is predicted to bulge significantly less than weaker starting materials. This highlights the importance of considering not only the stabilized cyclic properties but also the initial strength when assessing the behavior of these materials.
On Structural Integrity Assessment of Conveyor Tube for Ice Plug Formation in the Fuel Receiving Bay
Authors: Ghafouri-Azar Reza
Published: November 2024

One common approach to stop the flow and isolate the piping system in pressure retaining systems for maintenance activities is to freeze the fluid in the flow path connections, which is called ice plugging. This process entails challenges in the structural integrity of surrounding pressure boundary to the frozen flow due to exposure of the system to the environment with a significantly lower than normal temperatures, and temperature gradients.

In this paper the structural integrity of spent fuel conveyor system in CANDU nuclear power plants is reviewed when exposed to the cryogenic process using the requirements of ASME Section III, Div. 1 [1] as well as the allowable flaw size for fracture mechanics requirements.

The conveyor tube geometry is not circular and consists of welded square sections. Since the cross-section is non-circular, the thermal contraction may create an uneven stress. An elastic Finite Element (FE) solid model is constructed for half of tube geometry using Abaqus[2]. Due to symmetrical feature of tube, a half-length of the ice-plug jacket is modeled. In the FE model, a refined mesh is created in the end of model area where the ice plug jacket wraps around the conveyor tube.

A combined thermal/structural transient analysis is performed to study thermal stresses build-up in critical locations. The acceptance criteria defined in NB-3000 of ASME Section III, Div. 1 1] is employed to qualify the result of assessment. It is concluded the system satisfies the acceptance criteria.

The other aspect that needs special attention is the brittle failure at cryogenic temperature. The methodology for calculating the allowable flaw size for surfaces expose to significant low temperature to avoid fracture failure is explained which can be used for an inspection of surface before the application of ice-plug.
Role of iron in the treatment of sepsis
Authors: Zhang Chenyang , Fang Zhiyao , Wang Kaixuan , Wang Jia , Wan Xianyao
Published: November 2024

Iron is an important microelement in human and microbial life activities. During the pathophysiological process of sepsis, iron metabolism changes and the body undergoes a series of changes to fight microbial infection. Meanwhile, alterations in iron metabolism during sepsis lead to the development of some diseases, such as transfusion-induced siderosis and anemia. In recent years, several studies have demonstrated the use of iron-chelating agents to fight microbial infections, and new antimicrobial agents have been developed using “Trojan horse” and siderophores immunity. In addition, the use of iron-based nanomaterials as drug delivery systems for gene delivery may be applied to the treatment of sepsis in the future. In this review, we describe the pathophysiological changes in the development and course of sepsis, focusing on the potential of iron in the treatment of sepsis.
HAXPES reference spectra of zirconium and zirconium oxide with Cr Kα excitation
Authors: Zheng Dong , Young Christopher N. , Stickle William F.
Published: November 2024

Hard x-ray photoelectron spectroscopy using monochromatic Cr Kα radiation (5414.8 eV) has been used to acquire XPS and Auger data on sputtered zirconium and zirconium oxide samples. Survey data, high-resolution scans of all observed photoelectron peaks, and high-resolution scans of Auger lines are presented herein.
Promoting Positive Mental Health in Portuguese and Brazilian Youth Sport: The Roles and Responsibilities of Policymakers, Coaches, and Coach Developers
Authors: Santos Fernando , Newman Tarkington J. , Vella Stewart , Camiré Martin , Rathwell Scott , Strachan Leisha , MacDonald Dany J. , Pierce Scott , Ferreira Marta , Milistetd Michel
Published: November 2024

Mental health is positioned as a key outcome of organised youth sport participation and is a public health priority around the world. However, discussions on the priority of and intersection between mental health and youth sport are just beginning in some countries. Portugal and Brazil have made efforts to reflect on the current state of sport and have considered initiatives targeting mental health promotion. Therefore, the purpose of the current paper is to advocate for policymakers, coaches, and coach developers to deploy efforts to promote and protect the mental health of youth athletes and expand on possible ways to achieve this. Portugal and Brazil are used as cases to discuss the processes and strategies needed for promoting mental health. These countries were chosen because they share many sociocultural similarities and have few provisions in place for promoting mental health in youth sport. This manuscript is intended to serve as an instigator for creating awareness among decision makers (e.g., policymakers and coach developers), in both countries and across their sport systems, about the relevance of promoting mental health in youth sport. Potential challenges to promoting and protecting mental health are discussed, and practical implications for coaching and coach education are offered.
Advancing alternative methods to reduce animal testing
Authors: Nelson Chad P. , Brown Paul , Fitzpatrick Suzanne , Ford Kevin A. , Howard Paul C. , MacGill Tracy , Margerrison Edward E. C. , O’Shaughnessy Jacqueline , Patterson Tucker A. , Raghuwanshi Rakesh , Rouse Rodney , Stromgren Selen , Sung Kyung E. , Valerio Luis G. , Ward Jeffrey L. , Bumpus Namandjé N.
Published: November 2024

Emerging approaches show promise for regulatory use
Diverse and larger tree islands promote native tree diversity in oil palm landscapes
Authors: Paterno Gustavo B. , Brambach Fabian , Guerrero-Ramírez Nathaly , Zemp Delphine Clara , Cantillo Aiza F. , Camarretta Nicolò , Moura Carina C. M. , Gailing Oliver , Ballauff Johannes , Polle Andrea , Schlund Michael , Erasmi Stefan , Iddris Najeeb A. , Khokthong Watit , Sundawati Leti , Irawan Bambang , Hölscher Dirk , Kreft Holger
Published: November 2024

In monoculture-dominated landscapes, recovering biodiversity is a priority, but effective restoration strategies have yet to be identified. In this study, we experimentally tested passive and active restoration strategies to recover taxonomic, phylogenetic, and functional diversity of woody plants within 52 tree islands established in an oil palm landscape. Large tree islands and higher initial planted diversity catalyzed diversity recovery, particularly functional diversity at the landscape level. At the local scale, results demonstrated that greater initial planting diversity begets greater diversity of native recruits, overcoming limitations of natural recruitment in highly modified landscapes. Establishing large and diverse tree islands is crucial for safeguarding rare, endemic, and forest-associated species in oil palm landscapes.
Tomorrow’s trees
Treekeepers: The Race for a Forested Future
Lauren E. Oakes
Basic Books, 2024. 336 pp.
Authors: Boon Sarah
Published: November 2024

An ecologist probes the future of forests
Heat up to catch carbon
Authors: Li He , Zhao Dan
Published: November 2024

A metal-organic framework is activated to capture carbon dioxide at high temperatures
How to build a human: Piecing together the body’s cellular puzzle
Authors: Shilts Jarrod
Published: November 2024

Piecing together the body’s cellular puzzle
Famed flipping ship gets second shot at research
Authors: Cummings Sean
Published: November 2024

Saved from the scrapyard, unique ocean platform to be revamped before redeployment
Inside the Atacama Desert: uncovering the living microbiome of an extreme environment
Authors: Bartholomäus Alexander , Genderjahn Steffi , Mangelsdorf Kai , Schneider Beate , Zamorano Pedro , Kounaves Samuel P. , Schulze-Makuch Dirk , Wagner Dirk
Published: November 2024

The Atacama Desert in Chile is one of the driest and most inhospitable places on Earth. To analyze the diversity and distribution of microbial communities in such an environment, one of the most important and challenging steps is DNA extraction. Using commercial environmental DNA extraction protocols, a mixture of living, dormant, and dead cells of microorganisms is extracted, but separation of the different DNA pools is almost impossible. To overcome this problem, we applied a novel method on soils across a west–east moisture transect in the Atacama Desert to distinguish between extracellular DNA (eDNA) and intracellular DNA (iDNA) at the cell extraction level. Here, we show that a large number of living and potentially active microorganisms, such as
Acidimicrobiia
,
Geodermatophilaceae
,
Frankiales
, and
Burkholderiaceae,
occur in the hyperarid areas. We observed viable microorganisms involved as pioneers in initial soil formation processes, such as carbon and nitrogen fixation, as well as mineral-weathering processes. In response to various environmental stressors, microbes coexist as generalists or specialists in the desert soil environment. Our results show that specialists compete in a limited range of niches, while generalists tolerate a wider range of environmental conditions. Use of the DNA separation approach can provide new insights into different roles within viable microbial communities, especially in low-biomass environments where RNA-based analyses often fail.

IMPORTANCE

The novel e- and iDNA separation technique offers insights into the living community at the cell extraction level in the hyperarid Atacama Desert. This approach provides a new framework for analyzing the composition and structure of the potentially active part of the microbial communities as well as their specialization, ecological network and community assembly process. Our findings underscore the significance of utilizing alternative genomic techniques in low-biomass environments where traditional DNA- and RNA-based analyses may not be feasible. The results demonstrate the viability of the proposed study framework and show that specialized microorganisms are important in initial soil formation processes, including microbial-driven mineral weathering, as well as the fixation of carbon and nitrogen.
Inhibition of protein kinase D and its substrate phosphatidylinositol-4 kinase III beta blocks common human coronavirus replication
Authors: Han Huijuan , Liu Huan , Steiner Rebbeca , Zhao Zhijun , Jin Zheng-Gen
Published: November 2024

Coronavirus disease 2019 (COVID-19) is caused by the infection of a coronavirus, named as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Coronaviruses can be replicated in the infected host cells. Coronavirus replication involves various steps, including membrane fusion, peri-nuclear particle formation, and matrix vesicle transport to the cell membrane
via
the endoplasmic reticulum–Golgi-lysosome route. Recent studies have suggested that protein kinase D (PKD) plays a crucial role in regulation of vesicle formation and trafficking in the trans-Golgi network (TGN). Thus, we hypothesize that inhibiting PKD and its associated pathway could be an effective strategy to limit viral replication. Here, we report that molecular and pharmacological inhibition of PKD and its substrate phosphatidylinositol-4 kinase III beta (PI4KIIIβ) significantly diminishes the replication of common human coronaviruses. Specifically, we found that the PKD-silencing siRNA and the PKD inhibitor CRT0066101 have broad-spectrum antiviral activity against HCoV-OC43, HCoV-NL63, and HCoV-229E in cultured cells. Mechanistic studies revealed that the deactivation of PKD reduced the activation of PI4KIIIβ, thereby blocking the transport of viral particles in the host cells. Furthermore, the PI4KIIIβ inhibitor, BQR695, also exhibited antiviral activity against those coronaviruses. In conclusion, PKD and its substrate, PI4KIIIβ, may serve as novel antiviral targets for human coronaviruses and warrant further investigation.

IMPORTANCE

Human coronaviruses can lead to a range of clinical symptoms, from asymptomatic infection to severe illness and death, with a limited array of antiviral drugs available. Protein kinase D (PKD) is involved in various cellular processes, such as cell proliferation, apoptosis, and membrane fission of the Golgi apparatus. However, the specific role of PKD in the human coronavirus life cycle remains unclear. In this study, we found that PKD inhibitors effectively attenuated human coronavirus replication at the trans-Golgi network (TGN) stage in the viral life cycle. Furthermore, inhibiting PKD reduced PI4KIIIβ activation, thereby blocking viral replication in the host cells. Importantly, PI4KIIIβ inhibitors also blocked human coronavirus replication. Thus, PKD may represent a promising therapeutic target against both current circulating and future emerging coronaviruses.
Multi-stage tectonic record of the Central Sakarya Terrane Basement (NW Turkey): Implications for the Paleozoic evolution of Rheic Ocean and northern Gondwanan margin
Authors: Yasar I. Dogancan , Sayit Kaan , Miller Brent V. , Hames Willis E. , Koralay O. Ersin , Jeong Youn-Joong , Göncüoğlu M. Cemal
Published: November 2024

In northwestern Turkey, within the Central Sakarya Terrane, the Söğüt Metamorphics is one of the Variscan tectonic units preserved as a pre-Jurassic basement assemblage of the Sakarya Composite Terrane (SCT). It consists of para- and orthogneisses that host bands, lenses, boudins, and tectonic slices of amphibolites, and are altogether intruded by the Sarıcakaya Granitoid. The characterization and timing of the precursor magmatic events for the protoliths of this assemblage and the timing and conditions of metamorphism have been the topics of a long-lasting debate. Here we present new geochemical and geochronological data from the Söğüt orthogneisses, amphibolites, and the crosscutting Sarıcakaya Granitoid to provide further understanding of the geodynamic evolution of the SCT Basement and the larger-scale tectonic events that controlled its formation. Available geological and geochronological data indicate that the generation of the orthogneiss protoliths began in the Late Cambrian (ca. 485 Ma) and continued until the middle Silurian (ca. 430 Ma), accompanied by the subduction of the Iapetus Ocean and its progressive roll-back beneath northern Gondwana. The slab roll-back caused mantle-upwelling and Ordovician (ca. 465 Ma) continental rift-related mafic magmatism, eventually leading to the opening of the Rheic Ocean. Prior to the Variscan orogeny, a short-lived episode of middle Carboniferous (ca. 336–328 Ma) intra-oceanic arc magmatism occurred within the Rheic Ocean north of the SCT. Accretion of all this material and continuous subduction beneath the SCT led to a two-stage metamorphism during the late Carboniferous (ca. 326–324 Ma and ca. 318 Ma) and synchronous generation of granitic (ca. 327–324) and dioritic (ca. 319–317 Ma) rocks of the Sarıcakaya Granitoid during the Variscan orogeny, terminating the life cycle of the Rheic Ocean.
Outlier ophthalmologists in the treatment of neovascular age-related macular degeneration with intravitreal therapy
Authors: Hashimoto Yohei , Hunt Adrian Robert , Wells Jane M , Banerjee Gayatri , Ferrier Ross , Barry Richard , Field Andrew , Game Justin , Hooper Claire Yvonne , Barthelmes Daniel , Gillies Mark C
Published: November 2024

Background

To compare individual ophthalmologists grouped as outliers or non-outliers based on the mean 12-month visual acuity (VA) outcomes for their patients with neovascular age-related macular degeneration (nAMD).

Methods

This prospectively designed database study included treatment-naïve eyes with nAMD starting vascular endothelial growth factor inhibitors between July 2018 and April 2023 in Australia. Ophthalmologists were classified into high outliers, non-outliers and low outliers with a funnel plot of the adjusted mean 12-month VA change. The number of injections, last injection interval and proportion of visits where choroidal neovascularisation was active were compared between the groups.

Results

38 ophthalmologists who treated a total of 1266 eyes (male, 35%; mean age, 81 years old) were classified into 1 high outlier, 34 non-outliers and 3 low outliers (mean VA change, 7.5, 5.1 and 2.5 letters, respectively). The high outlier gave significantly more injections than the non-outliers (mean, 8.6 vs 7.7; p<0.001), while the low outliers administered significantly fewer injections than the non-outliers (mean, 7.1 vs 7.7; p=0.009). The last injection interval was shortest in the high outlier’s eyes (9.4 weeks), followed by non-outliers’ (10.8 weeks; p=0.04 (vs high outlier’s)) and low outliers’ (11.8 weeks; p=0.22 (vs non-outliers’)). The low outliers’ patients had more visits with intraretinal fluid (59%) than non-outliers’ (29%; p<0.001) and high outlier’s patients (31%; p<0.001).

Conclusion

The low outliers’ eyes had fewer injections, a longer treatment interval and more visits with intraretinal fluid. Building a system through which low outliers are anonymously notified of their performance would help improve general quality of care.
Late-onset myopathy responsive to immunomodulatory treatment: sporadic late-onset nemaline myopathy without nemaline rods?
Authors: Sadeh Menachem , Fellig Yakov , Dabby Ron
Published: November 2024

Background

Late-onset sporadic nemaline myopathy (SLONM) is a rare, treatable or potentially life-threatening muscle disorder that typically manifests late in life and is characterised by the presence of nemaline rods within muscle fibres, serving as the hallmark of the disease and the key to diagnosis.

Methods

We report a case of an elderly patient with subacute onset of severe weakness affecting the upper and lower limbs, neck extensors and abdominal muscles. A comprehensive laboratory workup was performed.

Results

Muscle biopsies showed nonspecific myopathic changes without inflammation, and electron microscopy did not reveal rods or aggregates. The laboratory workup was unremarkable except for the detection of monoclonal gammopathy of undetermined significance. Steroid treatment was ineffective; however, there was a notable positive response to intravenous immunoglobulins. The neurological findings, subacute course, normal creatine kinase levels, presence of monoclonal gammopathy of unknown significance and responsiveness to immunoglobulin treatment but not to steroids align with the characteristics of SLONM.

Conclusion

We propose that the diagnosis of SLONM should be considered even in the absence of nemaline rods in muscle biopsy, and this should not impede the consideration of immunomodulatory treatment. Future progress in understanding the pathogenetic basis of SLONM may reduce reliance on pathological findings in muscle biopsies for establishing the diagnosis.
Remote SOC and SOH Estimation of High Energy Lithium Batteries Based on Dual-Mode Extended Kalman Filter Algorithm
Authors: Xu Renbo
Published: November 2024

Lithium battery, as its main power source, needs to ensure the safety of drivers and passengers not only under some complex external conditions, but also under harsh use conditions, even when damaged. At some point throughout this process, it is required to evaluate the status of the battery itself in order to assure safe usage of the battery and to develop a more effective battery management plan. SOC, SOH, and condition of power are all variables that are commonly used to describe the state of a lithium battery (SOP). The ability of the battery to constantly provide or receive power, the remaining service the life cycle of the battery, and the ability of the battery to output or receive power promptly are all described by these three characteristics. In order to effectively evaluate the health status of batteries, this paper proposes a dual-mode extended Kalman filter (EKF) algorithm for the remote estimation of SOC and SOH of high-energy lithium batteries. In the estimating procedure, the open circuit voltage (OCV) is also included as a state variable in the iterative process, which allows for more accurate results. In this paper, the state space equation is established based on the first-order RC equivalent circuit model, and the battery state estimation and parameter identification are completed by using the double EKF (the dual extended Kalman filtering, DEKF) algorithm, resulting in the realization of the estimation of SOC and SOH.
A note on the Q-integrability of complete bipartite graphs with self-loops
Authors: Pervin Jesmina , Selvaganesh Lavanya
Published: November 2024

A graph [Formula: see text] is [Formula: see text]-integral if its signless Laplacian has only integral eigenvalues. Suppose [Formula: see text] be the graph after adding a self-loop to every vertex of a subset [Formula: see text] of [Formula: see text]. In this paper, we prove that for a nonempty proper subset [Formula: see text] of [Formula: see text], [Formula: see text] is [Formula: see text]-integral if and only if [Formula: see text] and self-loops are added in exactly two vertices of each partite set, or [Formula: see text] and self-loops are added to all the vertices of one partite set. Besides, we prove that if [Formula: see text] is a nonempty proper subset of [Formula: see text], then [Formula: see text] is [Formula: see text]-integral if and only if [Formula: see text] and self-loops are added to all the pendant vertices. Using these results, we also answer when the matrix [Formula: see text] have only integral spectrum, where [Formula: see text] is any [Formula: see text]-diagonal matrix and [Formula: see text] is permutation similar to either [Formula: see text] or [Formula: see text].
Research on Financial Market Prediction Model Based on Big Data and Quantum Computing
Authors: Wang Hongwu , Hong Cheng , Zhu Shaotao
Published: November 2024

A financial market is a trading system for financial assets such as derivatives, stocks, currencies, and bonds. Financial markets, which can be virtual or physical, are essential to the world economy. Financial forecasting has become an enormous difficulty due to the markets’ quick internationalization and the volume of data gathered from various sources growing at an accelerating rate. The study explores the creation of a model for stock market forecasting that leverages the power of big data analytics and quantum computing (QC). By handling multifaceted datasets and achieving high-accuracy forecasting, big data and QC improve market trends and insights. This is achieved by leveraging QC speed-driven problem-solving capabilities. In this study, we proposed a novel Hippopotamus Optimized Quantum Refined Support Vector Machine (HO-QRSVM) to predict the financial market. The financial dataset came from several places, such as economic databases and stock exchanges. The preprocessed data from the acquired data were cleaned and normalized. To remove dimensionality and extract features from preprocessed data, principle component analysis (PCA) is used. The capacity of QC to handle entanglement and superposition enables the simultaneous investigation of several potential market situations, leading to faster convergence and more precise forecasts. The result demonstrated the proposed method has significant improvements in prediction accuracy compared to other traditional algorithms. The performance evaluation techniques include the F1-score (96.3%), recall (98.2%), accuracy (98.5%), and precision (98.3%). The research, big data analytics, and QC combined can greatly improve financial market forecasts, giving decision-makers and strategic investors an advantage over their competition.