bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on Improved Vibration Damping Performance of the Elasto-Plastic Damper on Vibration of Connected Cabinets Storing Electronics Subjected to Seismic Wave
Authors: Shintani Atsuhiko , Michishita Yasunari , Nakagawa Chihiro , Ito Tomohiro
Published: November 2024

Vibration mitigation of adjacent cabinets storing electronics inside subjected to seismic waves is studied here. Cabinets are often seen in many plants, as power plants, chemical plants, and so on. In some cases, the cabinets often cannot be fixed to the floor or wall, and some of the cabinets are placed on the floors of the plant directly. The cabinets store the important electronic devices inside, which control the entire plant. Recently, large earthquakes have been occurring all over the world. When the plants are subjected to the earthquake, sliding or rocking motion of the cabinets occurs, and cabinets may be damaged or destroyed. In case of large acceleration amplitude, the cabinets may turn over, and the electronic device may be destroyed. Consequently, the whole plant may not work. Even if the cabinets do not turn over, the electronic device is subjected to a large earthquake, and the electronic device does not work well. Hence, it is very important to increase the safety of the cabinets and electronic devices simultaneously when subjected to the large earthquake. Even in such a case, the vibration of cabinets and electronics can be mitigated by connecting the adjacent cabinets with nonlinear dampers. In this study, vibration mitigation of the cabinets and electronic devices subjected to seismic waves is investigated. First, an analytical model of the connected cabinets storing electronic devices inside is derived. The cabinets are modeled by the rigid bodies rotating around their corners. The electronic devices are modeled by the mass moving parallel to the bottom of the cabinets. The cabinets are connected by elasto-plastic dampers, which have bilinear characteristics. The energy of the earthquake is absorbed by these dampers. Next, the responses of the cabinets and electronic devices are also investigated by numerical simulation. Since the structural responses depend on parameters of the mass ratio of cabinet and electronic device, the natural frequency of the electronics, support position of the elasto-plastic damper, input amplitude, input frequency, and so on, the effects of these parameters are investigated. Finally, the conditions to improve the damping performance of the cabinets and electronic devices are discussed.
Impact of Texture on Mechanical Properties of Stainless Steel (SS316) Material Using a Polynomial Chaos-Based Surrogate Model With Crystal Plasticity Simulations
Authors: Kumar Dinesh , Wilcox Paul , Knowles David , Mostafavi Mahmoud
Published: November 2024

In this work, we propose a framework to study the impact of texture (preferred grain orientations such as Goss, Brass, Copper, Cube, etc.) on the mechanical properties of materials using machine learning and micro-mechanics models. For micro-mechanics of materials, crystal plasticity finite element (CPFE) models are used. A polynomial chaos-based surrogate model is employed with an in-house crystal plasticity solver, BRISTOL. The framework is tested for the stainless steel SS316 material, where the CPFE modeling is used to correlate the micro-structure characteristics to macro-mechanical behavior. First, for the crystal plasticity simulations, a converged RVE (Representative Volume Element) is constructed using an open-source toolbox Dream3D. Further, texture uncertainties are propagated to the crystal plasticity model to quantify the impact of texture uncertainties. In this analysis, the uncertainty bounds for the textures are extracted from experimental data.
Applicability of ASME Code, Section XI to Fatigue Crack Growth Calculation of Flaws in Pipe-to-Elbow Welds
Authors: Hong Chan-Gi , Yoon Seok-Jun , Lee Gi-Bum , Huh Nam-Su , Shim Do Jun
Published: November 2024

The American Society of Mechanical Engineers Boiler & Pressure Vessel (ASME B&PV) Code Section XI provides procedures for fatigue crack growth calculation which can be used for flaw evaluations. However, the solutions in ASME B&PV Code Section XI are for straight pipes, making it potentially unsuitable for evaluating flaws at pipe-to-elbow welds. To address this limitation, the stress field at the pipe-to-elbow weld cross-section is used in the straight pipe solution to calculate the stress intensity factor for crack growth calculations. This feasibility study aims to verify the accuracy of ASME B&PV Code Section XI procedure in predicting circumferential fatigue crack growth in actual pipe-to-elbow configurations. For this purpose, a natural crack growth simulation program based on finite element analysis using adaptive meshing was used to perform the verification. The reliability of the program was first established by comparing its stress intensity factor calculations with those obtained from ASME B&PV Code Section XI procedure for various flaw geometries in straight pipes. Subsequently, natural fatigue crack growth calculations were performed for circumferential flaws in pipe-to-elbow configurations. These results were compared against ASME B&PV Code Section XI results using the pipe-to-elbow interface stress fields. Comparisons were made for various pipe-to-elbow configurations, loading, and two different initial crack sizes.
Numerical Study of the Pressure-Displacement Synchronization on Fluidelastic Instability
Authors: Farani Sani Hossein , Hassan Marwan , Moran Joaquin
Published: November 2024

This paper presents a Fluidelastic instability (FEI) model in tube array subjected to two-phase flow. The model utilizes the flow cell concept of the Hassan and Weaver fluidelastic model. The methodology involves discretizing the channel two-phase flow into a set of multiple layers, each characterized by distinct void fractions following flow regime dependent probability distribution functions. Layer-specific thickness variations are incorporated to reflect the diverse void fraction profiles. The proposed model aims to address the complexities of fluidelastic instability in the presence of two-phase flows. The proposed model was utilized to simulate a parallel triangle array for various void fractions. The predicted stability threshold for a range of void fractions was compared with the available data in the literature for water-air flow. The model shows great potential to simulate the response of tube arrays due to two-phase flow excitation.
A Study on the Degradation of Pre-Applied Threadlockers Under Extended Exposure to Severe Hygro-Thermal Conditions
Authors: Fini Stefano , Croccolo Dario , de Agostinis Massimiliano , Mele Mattia , Olmi Giorgio , Scapecchi Chiara , Tariq Muhammad Hassaan Bin
Published: November 2024

Pre-applied threadlockers are characterized by several favorable features in terms of handling of the fastener and simplification of the assembly process. Very often, fasteners with pre-applied adhesive undergo storage and shipping in harsh environmental conditions: these may encompass both exposure to elevated temperatures and to high levels of ambient humidity. Previous studies by the authors highlighted how the performance of the adhesive, both in terms of tribological response and of breakaway torque may be impaired, when specific exposure conditions apply. This study aims at better understanding the phenomenon of hygro-thermal degradation of the adhesive, more specifically, when longer exposure periods take place. The study is based on two sets of identical specimens (zinc coated steel screws): one set has been exposed to hygro-thermal degradation for 1 month at T = 90°C and rh = 95% and the other set has been kept at RT and rh = 50%. The screws have then been tightened (underhead and thread c.o.f. values have been recorded on a sample for each population), then cured and finally released. All measurements have been performed by means of a tightening test bench that allows sampling the separate frictional contributions at the underhead and at the thread. The outcomes of the study reveal a different behaviour of the two populations, which is in line with the literature.
A Methodology for Using Mechanical Compression Joint Fittings on ASME Section III Small Bore Pipework
Authors: Wilson James , Greenwood Oliver
Published: November 2024

Mechanical compression joint fittings (MCJF) are supported for use by ASME Section III for small bore pressure-retaining nuclear pipework applications. These joints can be quickly disassembled and re-assembled a number of times, providing easy access for maintenance or inspection benefit. MCJFs can also be more easily assembled within tight space constraints and do not require the expensive and more onerous quality assurance practices associated with welds. They may also be used to facilitate modular build in order to reduce build costs and timescales. One limitation with MCJFs is that it is difficult to demonstrate the same high reliability obtained with the equivalent welded joint and they are perceived to be more susceptible to assembly variation, crevice corrosion and shock.

ASME Section III limits the use of compression fittings to 25mm nominal bore for Class 1 and 50mm nominal bore for Class 2 and Class 3. The rationale relates to the capacity of typical leak protection systems of large-scale plants to mitigate in the unlikely event of a full-bore failure of a compression fitting. However, for a small-scale plant, where the leak protection system, although adequate, may be more limited, more onus is placed on demonstrating the high reliability of compression fittings. These concerns are equally applicable to low-redundancy or high-consequence joint locations on any plant.

This paper presents a methodology for justifying replacement of welded joints with MCJFs for nuclear plant applications, with particular relevance to small scale plants that may have relatively limited leak protection systems. The paper includes a review of requirements for Quality Assurance (QA) practices, a comprehensive testing programme and operational experience to substantiate against reliability, quality and failure criteria.
Evaluation of the Simplified Assessment Peak Equivalent Stress Design Limit Probability of Failure
Authors: Walker Adam P. , Mack Andrea L.
Published: November 2024

The ASME Boiler and Pressure Vessel Code Section III Division 5 Subsection HH Subpart A (HHA) outlines requirements and qualification methods for graphite core components in high temperature reactor environments. One such structural qualification method is the Simplified Assessment outlined in HHA-3220, which represents a comparison of service level specific equivalent stresses to allowable stress values derived from target probability of failures (POFs). The target POF is based on the structural reliability class (SRC) for the components and service condition of interest, and is used to establish design limits for combined membrane and peak equivalent stresses. Combined membrane stress limits are derived from two parameter Weibull distribution fits of the graphite grade specific tensile strength data and the target POF. The combined membrane stress limits are then scaled based on the ratio of flexural strength to tensile strength (referred hereinafter as Rtf) to establish the corresponding peak equivalent stress limits. It is desired that the target POF is at least maintained for both combined membrane and peak equivalent design limits, especially with the use of Rtf. The assessment presented herein examines tensile and flexural data for medium and fine grade graphites relative to the calculated combined membrane and peak equivalent stress limits per HHA-3220 and illustrates the simplified assessment method results in anticipated, or at least conservative, peak equivalent design stress limits.
Study of High Temperature Strain Gages As They Apply to Asset Life Management Programs
Authors: Subramanian Kannan , Crompton Andy , Horvath Roland
Published: November 2024

Life cycle management of coke drums often relies on empirical data from operational experience and strain gage measurements to inform predictive models. Many data-driven models treat these measurements as absolute values, often without validating analytically predicted errors or accounting for test and measurement inaccuracies even with temperature compensations.

In this study, three commercially available resistive temperature-compensated strain gages are investigated using static axial strains and furnace testing up to 450°C (with different temperature transients), benchmarked against a load cell. Initially, the focus was on assessing the overall accuracy of these gages for their intended applications. However, test results reported in this study indicate that the temperature compensation can adversely affect strain readings, resulting in errors exceeding 50%.

This investigation expanded to scrutinize the accuracy of temperature compensation in the gages, explore correction techniques involving apparent strain functions, and examine gage factors — factors that influence the readings used as benchmarks for prediction models.

This paper presents the findings of our testing, which underscore concerns employing resistive gages in predictive analytics, emphasizing the need for careful consideration of these factors in model validation and fatigue life estimation.
Duplex Stainless Steel Bolts for Flange Application
Authors: Panchal Anilkumar , Naqvi Kazim , Daru Kuntak , Gala Punita
Published: November 2024

For heat exchangers made of duplex stainless steel, the bolts exposed to the process fluid need to be made of an equal or higher corrosion resistant material compared to duplex stainless steel. There is no ASME specification for duplex bolts in the ASME Section II-D, Table 3. However, there is rod specification SA-479 from duplex stainless steel UNS S32205 and accordingly allowable stresses are listed in Table 1A. The authors came across a heat exchanger wherein SA-479-S32205 was specified as the girth flange bolting as well as nozzle bolting. Heat exchanger girth flanges were designed using commercial computer program. The design considered SA-479-S32205 as the girth flange bolting without recognizing that SA-479-S32205 is a rod specification and therefore is not acceptable for it to be used as flange bolting under the ASME Code.

Heat exchanger was constructed according to ASME Section VIII, Division 1 and was shipped to user’s site. The owner’s engineer noticed that the SA-479-S32205 is not listed in Table 3 of ASME Section II, Part D and hence it cannot be used as the girth flange bolting specification. It was decided to replace the bolts with a proper ASME bolt material which satisfied allowable stresses in Table 3 of ASME Section II-D. Since the heat exchanger was under sour service it was also necessary that the bolting met hardness requirements of NACE MR0103 [6]. Due to higher allowable stresses of SA-479-S32205 incorrectly used per Table 1A for the flange design, the engineers had limited options to choose appropriate replacement corrosion resistant bolting specification which also equaled or surpassed the original allowable stress value used in design for the flange design to not fail.

This paper discusses the events which occurred and how the duplex stainless steel bolts were replaced with appropriate bolts ensuring compliance to ASME Section VIII, Division 1, and NACE MR 0103 requirements.
Fitness-for-Service of In-Service Thermowells via Experimental Damping Tests
Authors: Bifano Michael F. P. , Calko Thomas
Published: November 2024

Increasing demands on energy infrastructure push throughput of our existing Oil & Gas, PetroChemical, and Midstream facilities. Thermowells (TWs) are used to measure the process temperatures in the pipe flow. These cylindrical protrusions into the flow are designed to ASME PTC 19.3 to prevent vortex shedding-induced vibration fatigue due to lock-in at the TW mechanical natural frequency. When throughput increases, an existing TW may no longer meet the ASME design. In such cases, engineers must decide whether to quantify the risk of leaving the TW in-service using advanced analysis methods or replace it.

A case study is presented on a Fitness-for-Service (FFS) assessment of TWs left in-service following a change to operating conditions subjecting the TWs to inline resonance. The outcome of the FFS depends on the assumed damping factor which can be accurately determined by experimental testing of identical TWs. This paper presents experimentally tested damping factors of 13 TWs having 8 have unique geometries. The TWs were installed in a test apparatus closely simulating the as-installed in-service condition. The results are presented based on the geometry of the TWs, the assembled bolt torque, and with and without the sensing elements. Surprisingly, the presence of a sensing element is the most critical variable governing damping.

Experimental damping testing for use in FFS assessments is not a common industry practice. However, the technology presented and fatigue design requirements used herein are based on sound engineering practices and principles. This work offers insight into how the risks of operation of these TWs can be best managed until more permanent replacements can be made to align with the ASME PTC 19.3 updated requirements for inline resonance.

The results of this study highlight the feasibility of performing damping tests to verify the FFS of in-service TWs that may not comply with PTC 19.3 requirements due to changes in operating conditions that were not accounted for in the original design. Additionally, a modified damping factor is provided for FFS assessments on in-service TWs when the sensing element is left inserted in the bore of the well.

This work benefits the industrial use of TWs since shutting down a plant/unit/or facility is not typically economical just because a TW is identified as not complying with its original design conditions.
Peel Strength of Multilayer Polymer-Based Pipes
Authors: Dua Mahima , Hammami Ahmed , Mertiny Pierre
Published: November 2024

Multilayer polymer composite piping typically comprises a primarily load-bearing structural layer and one or two inner and outer protective layers. The latter aims to protect the structural layer from damage caused during installation and operation. Multilayer pipes are an attractive alternative to conventional single-layer composite piping and are sought for elevated temperatures and pressure operation for oil and gas transportation. Concerns associated with multilayer pipes are fluid permeation, lack of barrier performance, and inadequate adhesion between layers. Rapid gas decompression (RGD) testing replicates the rapid decrease in pressure that may occur in operation. It helps identify defects in the pipe design, materials, and/or fabrication, leading to layer separation and even pipe collapse. However, RGD testing is expensive, requires complex equipment, and may pose safety risks. Therefore, an alternative safe, expedient, and cost-effective procedure is sought. In response to this need, peel testing is investigated according to the DIN 53357 standard, also known as German wheel peel testing. A peel test apparatus has been adapted based on the DIN 53357 standard in the present work. Results from testing five-layer polymer-based pipes are reported in the present study. Baseline tests were performed at room temperature at a 10 mm/minute peel rate on a 10 mm wide and 2.5 mm thick peel strip. The influence of peel rate, peel strip width and thickness, and temperatures were investigated in this work. This contribution concludes with a discussion about the effects of these parameters and the suitability of peel testing for multilayer pipes.
Low-Computational-Cost Online Acceleration Compensation Method for High-Frequency Vibration and Experimental Verification on a 6-Degree-of-Freedom Shaking Table
Authors: Hosoda Ryo , Tagawa Yasutaka
Published: November 2024

Vibration experiments using shaking tables have been conducted to evaluate the seismic resistance of buildings and ground. Acceleration amplitude is an important parameter in vibration experiments and must be controlled accurately. Target value compensation and model-based control based on the input/output characteristics obtained from preliminary excitation experiments are generally performed. However, preliminary excitation experiments cannot be performed to observe irreversible responses, such as damage to the specimen due to excitation. Therefore, a control method that does not require trial excitation or that can obtain control parameters during excitation is required. This study poposed a method for measuring the amplitude of each wave in excitation targeting a sine wave and correcting the input online based on the measured amplitude. In the proposed method, the shaking table is a discrete-time plant with one input and one output, with the command displacement amplitude of one sine wave as the input and the measured acceleration amplitude as the output. This method was tested on an actual Stewart platform-type hydraulic shaking table. Compensation calculations were performed for each wave rather than for each calculation cycle of the controller, so the amount of calculation was less than that of methods that implement continuous time-domain controllers. Moreover, it can be implemented using inexpensive calculation equipment. The experiment started with no model, and the correction calculation converged in approximately two waves in the frequency band from 1 to 10 Hz. It was possible to excite with an acceleration amplitude control error of less than 0.3% in single-axis excitation and around 8% in three-axis excitation.
Defect Stability Evaluation in a Nozzle Through the Gfr Criterion Under Thermal Loading
Authors: Hamouche Walid , Marques Vieira Edith , Albrecht David , Chapuliot Stéphane , Ancelet Olivier , Marie Stéphane
Published: November 2024

The Gfr criterion is a global approach devoted to ductile crack growth assessments. This paper presents an industrial numerical application of the Gfr criterion for the ductile tearing crack growth prediction of a circular crack in the beak of a stainless-steel 45° inclined nozzle under both thermal and mechanical loading.

In the first part of the paper, the background of the Gfr criterion devoted to mechanical loading, its extension to through-the-thickness thermal loading and more generally secondary loading, and the protocol to apply it are presented.

After, we detail the application and the abilities of the Gfr criterion to estimate the crack growth in case of complex thermal mechanical loading conditions.
Fluid Characteristics and Droplet Evaporation Simulation Of T-Junction Pipe With Fouling Layers
Authors: Guan Chenfeng , Yan Sunting , Tang Ping , Chen Yonggui , Cheng Mao , Tao Yangji , Cheng Yanbin
Published: November 2024

Recently, a cracking failure with significant fouling layers occured at a T-junction pipe with superheated and saturated vapor inlets which motivated a flow analysis in the T-junction pipe considering various existing fouling laysers.

Analysis indicated that some of the water vapor in cold syngas exists as liquid droplets at the operating temperature and pressure. During the coal-to-gas process, liquid water dissolves and transports solid substances. The mixture is then heated and evaporated after being combined with hot syngas, causing the solid particles to accumulate downstream of the T-junction pipe.

The evaporation of droplets after mixing hot and cold syngas is numerically simulated. Discrete Phase Model (DPM) is used to simulate mass transfer processes and evaporation. The causes of scale formation are analyzed in conjunction with the products of scale formation.

The second goal of this study is to investigate the flow characteristics and the process of fouling removal in T-junction pipes. Fouling dynamics modeling is utilized to examine the impact of the sizes and positions of fouling layers on shear stress through numerical simulation.
Structural Modeling to Support Post-Yield Acceptance Criteria for Spent Nuclear Fuel Cladding
Authors: Klymyshyn Nicholas , Sakalaukus Peter , Kadooka Kevin
Published: November 2024

Spent nuclear fuel (SNF) is evaluated for structural failure during storage and transportation scenarios. The U.S. Department of Energy’s Spent Fuel and Waste Science and Technology (SFWST) program has sponsored significant research in quantifying mechanical loads on SNF during storage and transportation scenarios using experimental and modeling methods. The SFWST program has also performed significant research on measuring the mechanical behavior of irradiated SNF as defueled cladding segments and cladding with fuel pellets to measure composite behavior. This paper considers some of the key material data from the Sibling Pin testing and uses structural modeling and analysis methods that have been informed by testing to consider post-yield acceptance criteria for SNF cladding structural analysis.

Test data published by Oak Ridge National Laboratory (ORNL) and Pacific Northwest National Laboratory (PNNL) are the foundation for informing the material behavior of the models developed in this study. In particular, four-point bend (4PB) tests of fueled cladding segments together with data from axial tube tensile testing of defueled cladding segments provide significant information about the bending failure mode of SNF. ORNL’s 4PB test data is on fueled cladding segments, so the composite behavior of SNF is demonstrated. This paper describes PNNL’s coincident beam model that was developed to approximate the composite behavior of SNF.

This paper also presents PNNL’s structural dynamic finite element models of a cask tip-over scenario, which is predicted to cause the strongest mechanical loads on SNF of all postulated storage and transportation scenarios. SNF bending loads predicted in the cask tip-over scenario and cladding acceptance criteria beyond yield are considered, with justification based on the Sibling Pin test data. ASME Boiler and Pressure Vessel code stress intensity limits are also considered. The ultimate goal of this work is to aid in the justification of structural acceptance criteria for SNF cladding beyond the cladding’s irradiated yield strength for use in structural analysis of all storage and transportation scenarios.
Stress Intensity Factor Solution Comparison for Very Long Circumferential Flaws in Cylinders Using Finite Element Analysis
Authors: Glunt Nathan , Xu Steven X. , Cipolla Russell C.
Published: November 2024

Section XI of the ASME Boiler and Pressure Vessel Code provides analytical evaluation procedures to determine the acceptability of flaws detected during in-service inspection of structural components and piping. Linear elastic fracture mechanics-based evaluation procedures require calculation of the stress intensity factor. Article A-3000 of Appendix A in Section XI provides closed-form relations for the stress intensity factor influence coefficients at both the deepest and surface points of the flaw, which were developed based on tabular data in API 579-1/ASME FFS-1 2007. The API 579-1/ASME FFS-1 2007 data do not cover very long flaws, e.g., flaws close to being fully circumferential flaws. Stress intensity factor solutions are provided by separate equations for fully circumferential flaws in Article A-3000, but there is no guidance on evaluating very long flaws that are beyond the current closed form solutions and still fall short of being fully circumferential. Finite element calculations have been performed to obtain stress intensity factors for very long circumferential flaws in cylinders. The finite element results are used to assess the applicability of the current closed-form relations in Section XI Appendix A to very long circumferential flaws on the inside and outside surfaces of cylinders. The paper presents the finite element results and assessment of the applicability of the current Section XI equations.
Utilizing Probabilistic Analyses to Explore Performance Margins of Natural Gas Infrastructure for the Transport and Delivery of Hydrogen and Hydrogen Blends
Authors: Schroeder Benjamin , San Marchi Chris , Ronevich Joseph , Devin Michael , Duell Joshua , Potts Steve
Published: November 2024

Gaseous hydrogen is known to embrittle most steels, including the steels used in natural gas pipelines. As injection of hydrogen into the existing natural gas infrastructure is considered globally by the pipeline industry, the structural integrity of pipelines transporting gaseous hydrogen must be investigated. Hydrogen Extremely Low Probability of Rupture (HELPR) is a publicly available and open-source probabilistic fatigue and fracture mechanics toolkit recently developed at Sandia National Laboratories. HELPR is intended to incorporate the influence of hydrogen into structural integrity assessments of natural gas transmission and distribution infrastructure. HELPR utilizes engineering models, such as those specified in ASME B31.12 and API 579, with relatively low computational costs to perform large sample ensembles, enabling estimation of performance distributions including low probability tail estimates. Leveraging the probabilistic capabilities built into HELPR, the sensitivity of fatigue and fracture calculations to specific modeling parameters on performance margins can be quantified. Through applying HELPR’s probabilistic capabilities to realistic scenarios, the impact of uncertainty in specific model parameter descriptions on performance margins, such as cycles to unstable crack growth or rupture in gaseous hydrogen, can be characterized; this same approach can then be used to assess the impact of reducing uncertainty sources on the resulting performance metrics, margins, and associated risks. A few industry-motivated scenarios are used to demonstrate this approach.
Application of Torsional Fatigue Testing of Helical Springs to Explore the Effect of Mean Stress on Inconel X-750 Fatigue Resistance
Authors: Metzger Donald , Gagnon Andre
Published: November 2024

In a particular nuclear application, separation between structural components is maintained by a helical spring such that the separating load bears across the diameter of the spring coils. Relative motion between the structural components due to changing load and temperature is accommodated by rolling of the spring. This rolling motion while under radial load results in cyclic loading of the spring material. Fatigue analysis of the cyclic loading must take into consideration the material degradation due to the unique operating environment, so testing of ex-service material is required. Standard fatigue test specimens are not possible due to the small dimensions and helical form of the spring component.

A fatigue test system has been developed in which cyclic stress is achieved by applying torsional load with respect to the axis of the helical spring. This load results in a pure bending state of stress in the cross-section of the coils. The relationship between applied load and stress is achieved analytically through curved beam analysis. The fatigue test has previously only been applied with fully reversed load cycles with zero mean stress. In this work, test with non-irradiated specimens are done with mean stress controlled to be nonzero such that the effect mean stress on the S-N curve can be quantified. The outcome of the tests demonstrates that the test method is effective in producing valid fatigue data over a range of mean stress and alternating stress. Also, the test results add to the fatigue data available for Inconel alloy X-750.
A glutamine metabolic switch supports erythropoiesis
Authors: Lyu Junhua , Gu Zhimin , Zhang Yuannyu , Vu Hieu S. , Lechauve Christophe , Cai Feng , Cao Hui , Keith Julia , Brancaleoni Valentina , Granata Francesca , Motta Irene , Cappellini Maria Domenica , Huang Lily Jun-Shen , DeBerardinis Ralph J. , Weiss Mitchell J. , Ni Min , Xu Jian
Published: November 2024

Metabolic requirements vary during development, and our understanding of how metabolic activity influences cell specialization is incomplete. Here, we describe a switch from glutamine catabolism to synthesis required for erythroid cell maturation. Glutamine synthetase (GS), one of the oldest functioning genes in evolution, is activated during erythroid maturation to detoxify ammonium generated from heme biosynthesis, which is up-regulated to support hemoglobin production. Loss of GS in mouse erythroid precursors caused ammonium accumulation and oxidative stress, impairing erythroid maturation and recovery from anemia. In β-thalassemia, GS activity is inhibited by protein oxidation, leading to glutamate and ammonium accumulation, whereas enhancing GS activity alleviates the metabolic and pathological defects. Our findings identify an evolutionarily conserved metabolic adaptation that could potentially be leveraged to treat common red blood cell disorders.
Pathogenic proteotoxicity of cryptic splicing is alleviated by ubiquitination and ER-phagy
Authors: Prieto-Garcia Cristian , Matkovic Vigor , Mosler Thorsten , Li Congxin , Liang Jie , Oo James A. , Haidle Felix , Mačinković Igor , Cabrera-Orefice Alfredo , Berkane Rayene , Giuliani Giulio , Xu Fenfen , Jacomin Anne-Claire , Tomaskovic Ines , Basoglu Marion , Hoffmann Marina E. , Rathore Rajeshwari , Cetin Ronay , Boutguetait Doha , Bozkurt Süleyman , Hernández Cañás María Clara , Keller Mario , Busam Jonas , Shah Varun Jayeshkumar , Wittig Ilka , Kaulich Manuel , Beli Petra , Galej Wojciech P. , Ebersberger Ingo , Wang Likun , Münch Christian , Stolz Alexandra , Brandes Ralf P. , Tse William Ka Fai , Eimer Stefan , Stainier Didier Y. R. , Legewie Stefan , Zarnack Kathi , Müller-McNicoll Michaela , Dikic Ivan
Published: November 2024

RNA splicing enables the functional adaptation of cells to changing contexts. Impaired splicing has been associated with diseases, including retinitis pigmentosa, but the underlying molecular mechanisms and cellular responses remain poorly understood. In this work, we report that deficiency of ubiquitin-specific protease 39 (USP39) in human cell lines, zebrafish larvae, and mice led to impaired spliceosome assembly and a cytotoxic splicing profile characterized by the use of cryptic 5′ splice sites. Disruptive cryptic variants evaded messenger RNA (mRNA) surveillance pathways and were translated into misfolded proteins, which caused proteotoxic aggregates, endoplasmic reticulum (ER) stress, and, ultimately, cell death. The detrimental consequence of splicing-induced proteotoxicity could be mitigated by up-regulating the ubiquitin-proteasome system and selective autophagy. Our findings provide insight into the molecular pathogenesis of spliceosome-associated diseases.
Glaciation of liquid clouds, snowfall, and reduced cloud cover at industrial aerosol hot spots
Authors: Toll Velle , Rahu Jorma , Keernik Hannes , Trofimov Heido , Voormansik Tanel , Manshausen Peter , Hung Emma , Michelson Daniel , Christensen Matthew W. , Post Piia , Junninen Heikki , Murray Benjamin J. , Lohmann Ulrike , Watson-Parris Duncan , Stier Philip , Donaldson Norman , Storelvmo Trude , Kulmala Markku , Bellouin Nicolas
Published: November 2024

The ability of anthropogenic aerosols to freeze supercooled cloud droplets remains debated. In this work, we present observational evidence for the glaciation of supercooled liquid-water clouds at industrial aerosol hot spots at temperatures between −10° and −24°C. Compared with the nearby liquid-water clouds, shortwave reflectance was reduced by 14% and longwave radiance was increased by 4% in the glaciation-affected regions. There was an 8% reduction in cloud cover and an 18% reduction in cloud optical thickness. Additionally, daily glaciation-induced snowfall accumulations reached 15 millimeters. Glaciation events downwind of industrial aerosol hot spots indicate that anthropogenic aerosols likely serve as ice-nucleating particles. However, rare glaciation events downwind of nuclear power plants indicate that factors other than aerosol emissions may also play a role in the observed glaciation events.
The disciplinary matrix of holobiont biology
Authors: Bordenstein Seth R. , The Holobiont Biology Network  , Gilbert M. Thomas P. , Ginnan Nichole , Malacrinò Antonino , Martino Maria Elena , Bahrndorff Simon , Mundra Sunil , Martin Michael D. , Theis Kevin R. , Hird Sarah M. , Caro-Quintero Alejandro , Sharpton Thomas J. , Kohl Kevin D. , Barnes Christopher J. , Eisenhofer Raphael , Aizpurua Ostaizka , Andersen Sandra B. , Brealey Jaelle C. , Noer Christina L. , Medina Mónica , Limborg Morten T. , Alberdi Antton
Published: November 2024

Uniting life’s seen and unseen realms guides a conceptual advance in research
Sequence modeling and design from molecular to genome scale with Evo
Authors: Nguyen Eric , Poli Michael , Durrant Matthew G. , Kang Brian , Katrekar Dhruva , Li David B. , Bartie Liam J. , Thomas Armin W. , King Samuel H. , Brixi Garyk , Sullivan Jeremy , Ng Madelena Y. , Lewis Ashley , Lou Aaron , Ermon Stefano , Baccus Stephen A. , Hernandez-Boussard Tina , Ré Christopher , Hsu Patrick D. , Hie Brian L.
Published: November 2024

The genome is a sequence that encodes the DNA, RNA, and proteins that orchestrate an organism’s function. We present Evo, a long-context genomic foundation model with a frontier architecture trained on millions of prokaryotic and phage genomes, and report scaling laws on DNA to complement observations in language and vision. Evo generalizes across DNA, RNA, and proteins, enabling zero-shot function prediction competitive with domain-specific language models and the generation of functional CRISPR-Cas and transposon systems, representing the first examples of protein-RNA and protein-DNA codesign with a language model. Evo also learns how small mutations affect whole-organism fitness and generates megabase-scale sequences with plausible genomic architecture. These prediction and generation capabilities span molecular to genomic scales of complexity, advancing our understanding and control of biology.
Ribozyme-activated mRNA trans-ligation enables large gene delivery to treat muscular dystrophies
Authors: Lindley Sean R. , Subbaiah Kadiam C. Venkata , Priyanka Fnu , Poosala Pornthida , Ma Yijie , Jalinous Leila , West Jason A. , Richardson William A. , Thomas Tamlyn N. , Anderson Douglas M.
Published: November 2024

Ribozymes are small catalytic RNA sequences capable of nucleotide-specific self-cleavage found widespread in nature. Ribozyme cleavage generates distinct 2′,3′-phosphate and 5′-hydroxyl termini that resemble substrates for recently characterized RNA repair pathways in cells. We report that ribozyme cleavage of two separate mRNAs activated their scarless trans-ligation and translation into full-length protein in eukaryotic cells, a process that we named StitchR (for Stitch RNA). Optimization of StitchR activity in mammalian cells resulted in a ~900-fold increase in protein expression that approached levels observed for genes expressed from single vectors. We demonstrate that StitchR can be harnessed for effective dual adeno-associated virus gene therapies to correct muscular dystrophies by restoring large functional muscle proteins to endogenous levels in vivo.
Learning the language of DNA
Authors: Theodoris Christina V.
Published: November 2024

A genomic foundation model broadly enables sequence modeling, prediction, and design
The metaphors of artificial intelligence
Authors: Mitchell Melanie
Published: November 2024

A few months after ChatGPT was released, the neural network pioneer Terrence Sejnowski
wrote
about coming to grips with the shock of what large language models (LLMs) could do:

“Something is beginning to happen that was not expected even a few years ago. A threshold was reached, as if a space alien suddenly appeared that could communicate with us in an eerily human way.…Some aspects of their behavior appear to be intelligent, but if it’s not human intelligence, what is the nature of their intelligence?”
Gatekeepers of the brain: Identifying hidden mechanisms of type A GABA receptor signaling and assembly
Authors: Sente Andrija
Published: November 2024

Identifying hidden mechanisms of type A GABA receptor signaling and assembly
To target, to escape, perchance to cure: Borrowing a page from cancer’s playbook, scientists learn to evade their own therapies
Authors: Casirati Gabriele
Published: November 2024

Borrowing a page from cancer’s playbook, scientists learn to evade their own therapies
Science is neither red nor blue
Authors: McNutt Marcia
Published: November 2024

Long before the 5 November US presidential election, I had become ever more concerned that science has fallen victim to the same political divisiveness tearing at the seams of American society. This is a tragedy because science is the best—arguably the only—approach humankind has developed to peer into the future, to project the outcomes of various possible decisions using the known laws of the natural world. Since the founding of the National Academy of Sciences (NAS) during the Civil War, the most divisive period in US history, science and the NAS (of which I am the current president) have consistently served the nation, regardless of the political party in power. As the scientific community continues to do so now, it must take a critical look at what responsibility it bears in science becoming politically contentious, and how scientists can rebuild public trust.
In Science Journals
Authors: Lopez Bianca , Smith Keith T. , Grocholski Brent , Maroso Mattia , Yeston Jake S. , Smith Jesse , Hurtley Stella M. , Malo Courtney , Funk Michael A. , Jiang Di , Ray L. Bryan , Walia Ankit , Szuromi Phil , Osborne Ian S. , Isles Hannah M. , Ferrarelli Leslie K.
Published: November 2024

Highlights from the
Science
family of journals
In Other Journals
Authors: Stern Peter , Seale Madeleine , McCartney Melissa , Nusinovich Yevgeniya , Kelly Priscilla N. , Osborne Ian S. , Grocholski Brent
Published: November 2024

Editors’ selections from the current scientific literature
The counterattack
Authors: Couzin-Frankel Jennifer
Published: November 2024

An immune cell treatment that fights cancer is now taking aim at autoimmune disease
Research advocates see ‘no good news for science’
Authors: Mervis Jeffrey
Published: November 2024

Trump agenda and a Republican Congress point to funding cuts and policy shifts
Trump won. Is NIH in for a major shake-up?
Authors: Kaiser Jocelyn
Published: November 2024

Congress might serve as a bulwark, but some changes may be coming
Russia postpones three scientific ‘megaprojects’
Authors: Gerden Eugene
Published: November 2024

Economic sanctions, budget woes hamper progress on x-ray sources and neutron beams
Joint Modeling of Longitudinal and Survival Data
Authors: Wang Jane-Ling , Zhong Qixian
Published: November 2024

In medical studies, time-to-event outcomes such as time to death or relapse of a disease are routinely recorded along with longitudinal data that are observed intermittently during the follow-up period. For various reasons, marginal approaches to model the event time, corresponding to separate approaches for survival data/longitudinal data, tend to induce bias and lose efficiency. Instead, a joint modeling approach that brings the two types of data together can reduce or eliminate the bias and yield a more efficient estimation procedure. A well-established avenue for joint modeling is the joint likelihood approach that often produces semiparametric efficient estimators for the finite-dimensional parameter vectors in both models. Through a transformation survival model with an unspecified baseline hazard function, this review introduces joint modeling that accommodates both baseline covariates and time-varying covariates. The focus is on the major challenges faced by joint modeling and how they can be overcome. A review of available software implementations and a brief discussion of future directions of the field are also included.
Pharmacist Perceptions and Future Scope of Telepharmacy in New Zealand: A Qualitative Exploration
Authors: Saeed Hina , Scahill Shane , Kim Julie , Moyaen Raevienne , Natarajan Dharini , Soga Ayaka , Wong Manvis , Martini Nataly
Published: November 2024

Background: Telepharmacy is the delivery of pharmacy services through telecommunications technology when patients and pharmacists are separated by physical distance. Falling under the broader term of telehealth, telepharmacy has been adopted globally and proved invaluable during the COVID‐19 pandemic.

Objective: The study is aimed at investigating New Zealand pharmacists’ perceptions of telepharmacy adoption and assessing its potential impact on their future scope of practice.

Methods: New Zealand registered pharmacists were recruited through convenience sampling to participate in semistructured interviews conducted between July and August 2022. Interviews were transcribed and coded with NVivo and analyzed using inductive thematic analysis to develop themes. Themes and subthemes were mapped to the Clinical Adoption Framework (CAF) to interpret the findings.

Results: From 23 participants, 70% were community pharmacists. The COVID‐19 pandemic accelerated telepharmacy adoption in New Zealand and most pharmacists perceived it as convenient and beneficial to increase access to pharmacy services. Barriers such as the lack of resources, technology issues, inadequate remuneration, and existing legislation were highlighted, as was the need for better staff training, patient education, better access to technology, regulatory reforms, and integration with existing services.

Conclusion: There is a need for reforms and initiatives for sustainable and equitable telehealth use in New Zealand. While preparing for digital infrastructure and capabilities presents challenges, this investment can transform pharmacy practice in the long term, benefiting both patients and pharmacy professionals.
Unveiling the Link Between Breast Cancer Treatment and Osteoporosis: Implications for Anticancer Therapy and Bone Health
Authors: Goel Bhawna , Virmani Tarun , Jain Vikas , Kumar Girish , Sharma Ashwani , Al Noman Abdullah
Published: November 2024

Background: The interplay between breast cancer treatment and osteoporosis has important consequences for anticancer therapy and patient bone health. Many breast cancer therapies involve hormonal treatments that lower estrogen levels, which can lead to an increased risk of osteoporosis due to reduced bone mineral density. Aromatase inhibitors, chemotherapy, and surgeries such as oophorectomy can further aggravate bone loss, highlighting the necessity of prioritizing bone health during cancer treatment.

Objective: This review is aimed at investigating the complex relationship between breast cancer therapies and bone health by examining the molecular and cellular mechanisms through which anticancer treatments lead to bone loss. It also seeks to assess the effects of various treatment options, such as selective estrogen receptor modulators (SERMs) and bisphosphonates, on reducing bone loss and maintaining bone health during cancer therapy.

Method: The review explores the mechanisms underlying bone loss in breast cancer patients undergoing treatment, focusing on factors such as estrogen depletion, inflammatory cytokines, and changes in bone remodelling processes. Additionally, it evaluates the efficacy of different therapeutic interventions, including pharmacological treatments like bisphosphonates and third‐generation SERMs, in mitigating bone‐related side effects.

Results: The findings indicate a critical need to balance the effectiveness of breast cancer treatments with the preservation of bone health. Pharmacological treatments like bisphosphonates and denosumab have been identified as essential for managing bone health in breast cancer patients. Furthermore, third‐generation SERMs show potential in reducing bone loss associated with cancer therapy.