bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of the Applicability of Plutonium Transmuted From Minor Actinides by Fusion Reactor as Fertile Fuel in Boiling Water Reactor
Authors: Shimizu Masaki , Shishido Hiroki , Hashizume Hidetoshi
Published: October 2021

This study proposes to make effective use of plutonium transmuted from minor actinides (MA) by fusion reactors as fertile fuel in a light water reactor (LWR). The plutonium transmuted from MA, particularly Pu-238, has a large neutron capture cross section and becomes fissile Pu-239 by the reaction. If the plutonium transmuted from MA is loaded into LWR appropriately, there is a possibility to maintain a constant effective multiplication factor. This study evaluated the effects of the plutonium transmuted from MA on a full MOX boiled water reactor (BWR) core by Monte Carlo-based neutron transport and burnup calculation. We revealed that some fuel assemblies achieved the effective multiplication factor is greater than 1.0 and its decrease was significantly small (−0.013) during 400 days operation. However, under this condition, the power peaking factor was 1.4, which should be unacceptable from the viewpoint of thermal design. Inventories of heavy nuclides in fuel cycles was evaluated using a simple diagram and its result indicated that the accumulation of MA in the fuel cycle was reduced by introducing the MA transmutation and the Pu recycle system. Furthermore, the amount of MA production and MA transmutation are balanced by introducing two fusion reactors with 3 GW thermal output into the fuel cycle, and the MA inventory was equilibrated.
Chinese Public and Nuclear Experts May Have Different Perceptions Of Severe Nuclear Accidents
Authors: Wu Hsingtzu , Huang Leyao
Published: October 2021

Nuclear power has been a controversial social issue, and societal acceptance is critical to its development and future. In addition, risk informed rules and regulations rely on the public’s understanding. However, there seems a communication gap about nuclear safety between nuclear experts and the public in China, and three questionnaire surveys were conducted to better understand Chinese public’s perceptions of a severe nuclear accident. The sample sizes were 117, 280 and 1071. Most of the respondents were students or white-collar workers born after 1990. In these three surveys, we found that more than 85% of respondents consider a less severe accident as a severe nuclear accident, and most respondents considered an incident to constitute a severe nuclear accident. The results demonstrate that nuclear experts and Chinese public may have different definitions of a severe nuclear accident. Therefore, we suggest that the definition of severe accidents should be better explained to the public to benefit the communication about risk informed rules and regulations. In addition, our three different surveys yielded a similar result, and we anticipate that a questionnaire survey with a larger sample size would do the same.
Conceptual Study of Neutron Physics of Nuclear Fuel Cycle for Ceramic Fast Reactor
Authors: Yan Xuesong , Zhang Yaling , Gao Yucui , Yang Lei
Published: October 2021

To make the nuclear fuel cycle more economical and convenient, as well as prevent nuclear proliferation, the conceptual study of a simple high-temperature dry reprocessing of spent nuclear fuel (SNF) for a ceramic fast reactor is proposed in this paper. This simple high-temperature dry (HT-dry) reprocessing includes the Atomics International Reduction Oxidation (AIROX) process and purification method for rare-earth elements. After removing the part of fission products from SNF by a HT-dry reprocessing without fine separation, the remaining nuclides and some uranium are fabricated into fresh fuel which can be used back to the ceramic fast reactor. Based on the ceramic coolant fast reactor, we studied neutron physics of nuclear fuel cycle which consists operation of ceramic reactor, removing part of fission products from SNF and preparation of fresh fuels for many time. The parameters of the study include effective multiplication factor (Keff), beam density, and nuclide mass for different ways to remove the fission products from SNF. With the increase in burnup time, the trend of increasing 239Pu gradually slows down, and the trend of 235U gradually decreases and become balanced. For multiple removal of part of fission products in the nuclear fuel cycle, the higher the removal, the larger the initial Keff.
Machine Learned Metamodeling of a Computationally Intensive Accident Simulation Code
Authors: Conner Landon , Worrell Clarence L. , Spring James P. , Liao Jun
Published: October 2021

The nuclear power industry is increasingly identifying applications of machine learning to reduce design, engineering, manufacturing, and operational costs. In some cases, applications have been deployed and are realizing value, in particular in the higher volume and data rich manufacturing areas of the nuclear industry. In this paper, we use machine learning to develop metamodel approximations of a computationally intense safety analysis code used to simulate a postulated loss-of-coolant accident (LOCA). The benefit of an accurate metamodel is that it runs at a fraction of the computational cost (milliseconds) compared to the LOCA analysis code. Metamodels can therefore support applications requiring a high volume of runs, for example optimization, uncertainty analysis, and probabilistic decision analysis, which would otherwise not be possible using the computationally intense code. We first generate training data by running the safety analysis code over a design of experiment. We then perform exploratory data analysis and an initial fitting of several model forms, including neighbor-based models, tree-based models, support vector machines, and artificial neural networks. We select neural network as the most promising candidate and perform hyperparameter optimization using a genetic algorithm. We discuss the resulting model, its potential applications, and areas for further research.
Evaluation of Normalization Method With Crack Mouth Opening Displacement for Developing J-R Curves
Authors: Zhu Xian-Kui
Published: October 2021

Fracture toughness is an important material property used to characterize material resistance against crack tearing. In ASTM E1820 standard fracture toughness test method developed for metallic materials, the elastic unloading compliance method is recommended for measuring incremental crack growth and evaluating fracture resistance curve from a single specimen test in the conventional test conditions. For dynamic loading or other harsh conditions, on the other hand, ASTM E1820 suggests the normalization method as an alternative approach for estimating incremental crack length during stable crack tearing and for evaluating the J-integral resistance (J-R) curve from a single specimen test.

The normalization method is a semi-analytical methodology that was developed in the 1990s based on the load separation approach with use of load-line displacement (LLD) for a single edge notched bend (SENB) or compact tension (CT) specimen. This method has been extensively utilized to develop J-R curves using SENB and CT specimens for different steels in various loading and environmental conditions. Recently, the LLD-based normalization method was simply extended to use crack mouth opening displacement (CMOD) in determination of J-R curves for SENB and single edge notched tension (SENT) specimens. Based on the historical work for the LLD-based normalization method, this paper develops a fundamental basis for use of the CMOD-based normalization method. Experimental data measured from a single SENB specimen test are then used to evaluate the normalization method in determination of J-R curves using both LLD and CMOD. Finally, how to use the LLD-based or CMOD-based normalization method is suggested for developing a J-R curve.
Comparison of Vehicle-Mounted High-Pressure Hydrogen Storage Cylinders in United Nations Standards and Chinese Standards
Authors: Ding Ju , Yuan Yiwen , Yu Yixi
Published: October 2021

The hydrogen fuel cell vehicle industry has formed two major international standardization organizations, ISO, and International Electrotechnical Commission. ISO has formed a relatively mature evaluation system for electric vehicle performance indicators and test methods. However, in China, there are still deficiencies in the safety requirements and test evaluation methods in the field of hydrogen fuel vehicle components. The vehicle-mounted high-pressure hydrogen storage cylinder is a special equipment in Chinese current special equipment supervision and regulation system An important energy storage component of hydrogen fuel cells, it has a development history of more than 50 years in the world. However, Chinese national standard committee has not yet established a standard for type IV hydrogen storage cylinders, which had been used in Japan, U.S, and E.U. In this paper, the United Nations’ automotive high-pressure hydrogen storage cylinder standard ISO 19881:2018 and my Chinese standard GB/T 35544-2017, had been compared and analyzed, especially the specific differences in the manufacturing and inspection. China has been preparing to manufacture the type IV hydrogen cylinder standard nowadays. So it is very important to learn from foreign advanced experience, The purpose of this article is provide relevant instructs for manufacture, inspection and test, to formulate China’s vehicle-mounted hydrogen storage cylinders, and improves the conversion and application of standards.
Inspection Method of Finned Tube and Finned Heat Exchanger
Authors: Ding Ju , Zhang Min , Liu Shuhong , Wang Shenghui , Wang Jielu
Published: October 2021

The finned tube heat exchanger is one of the earliest and most successful discoveries in the process of improving tube heat exchange. This method is still the most widely used of all kinds of tube heat transfer surface enhancement heat transfer methods. It is not only suitable for single-fin tube heat exchangers, which are widely used in power, chemical, petrochemical, air-conditioning engineering and refrigeration engineering.

Conventional heat exchanger with smooth tubes can be inspected through the pressure test during the manufacturing process. Finned tubes and finned heat exchangers with inner thread structure have some difficult to pass the water pressure test. The same situation exists in regular inspections. Due to structural reasons, it is difficult to carry out regular surface inspections[1]. For these two situations, two different testing methods are required to ensure quality. This article introduces in detail the methods of inspecting finned tubes and finned heat exchangers. Hierarchical comparison of alternatives in hydrostatic testing project, and the eddy current detection technology of the finned tube under the condition of in-service air cooling. The far-field eddy current method is chosen for inspection. And by comparing the standard sample tube, it is mainly used to adjust the sensitivity of the eddy current detector and ensure the accuracy of the test results[2]. The results show that the eddy current detection technology can be more accurate and reliable. The corrosion of the finned tube under service air cooling is detected, and a reliable basis is provided for judging the use of the finned tube and finned heat exchanger[3].
Comparison of Tensile Test Results in High Pressure Gaseous Hydrogen Using Conventional and Tubular Specimens
Authors: Michler Thorsten , Wackermann Ken , Ebling Fabien , Oesterlin Heiner
Published: October 2021

Hydrogen environment embrittlement (HEE) of X60M pipeline steel was assessed by tensile testing with tubular specimen containing high pressure hydrogen in the axial hole. Residual oxygen content as well as strain rate were varied in order to define appropriate test parameters. Maximum HEE effects were found for oxygen contents below 2 vppm and strain rates below 5*10−4 s−1, which is in the same range compared to tensile testing in an autoclave using conventional specimens. Results at such tests parameters revealed that the tensile reduction of area in hydrogen is about 10% higher compared to a similar steel tested in an autoclave at identical test conditions using conventional specimens. Further investigations are required to verify, if this difference is caused by the specimen geometry.
Study on Ultrasonic Phased Array Detection and Imaging Techniques for Oil Storage Tank Floor Covered With Sludge
Authors: Cheng Jingwei , Chen Xuedong , Fan Zhichao , Chen Wei , Wang Zhe , Cheng Wei , Xu Wanbao
Published: October 2021

Ultrasonic testing is one of the most common non-destructive testing (NDT) methods for periodic inspection of crude oil storage tanks. Ultrasonic phased array system can effectively and efficiently image different types of defects in the structures through direct contact method. However, the sludge remained on the tank floor gives rise to difficulties on detecting the defects in the floor plate using existing techniques. Therefore, this paper focuses on the development of novel phased array testing methods without requiring complete removal of the sludge. The appropriate experimental apparatus and its parameters used for through-sludge testing are selected based on the acoustic characteristics of the oil sludge composition. Furthermore, a novel phased array full matrix capture method is explored based on firings of multi-element aperture. The total focusing method (TFM) is studied by considering the existence of sludge. The experimental results from the sludge thickness study demonstrate that the TFM imaging technique can more accurately measure the change in thickness of the metal sample at the submillimeter scale. Additionally, high resolution imaging of side drilled holes in size of 1 millimetre can be realized on the samples covered with sludge. Last, the effect of aperture size on the detectability is investigated. Consequently, the results obtained from different sludge experiments show good reliability and measurement consistency of our proposed methods. It delivers great potential to accurately locate and quantitatively evaluate the corrosion defects frequently found in the tank floor.
A Convolution Neural Network Based Fault Diagnosis Model for Slug Flow Condition of Oil-Gas Separator
Authors: Liu Jiaquan , Hou Lei , Wang Xin , Xu Lei , Zhang Rui , Yang Kai
Published: October 2021

The process of oil-gas separation is an important part of oilfield surface engineering. The oil-gas separator is the key equipment in this process. The composition of produced fluid from oil well is complex and the flow state of it changes frequently, which leads to the abnormal operating condition of the separator and affects the continuity of oil production. Therefore, the operating condition diagnosis of the oil-gas separator is extremely important for the system of oil production. Compared with the traditional threshold-based alarm method, the data-driven diagnosis method is more accurate and intelligent. According to the multivariate time series properties of the data of supervisory control and data acquisition (SCADA) system, the convolution neural network (CNN) is proposed to extract the multi-dimensional features of the oil-gas separator. Then based on the extracted features, the slug flow conditions of oil-gas separator are diagnosed, whose process is visually analyzed by t-distributed stochastic neighbour embedding (t-SNE). Finally, the data-driven diagnosis method of the oil-gas separator is realized, and the simulation data show that the average fault diagnosis rate of this method reaches 97.78%, which is 26.95% higher than that of the traditional method. The method proposed can diagnose the operating conditions of the separator accurately and quickly.
A Simple Method to Estimate Airborne Release Fractions Associated With the Pressurized Release of Radioactive Materials
Authors: Hensel Steve J. , Sprankle Ray A.
Published: October 2021

Pressurized release of radioactive materials, such as plutonium bearing oxides, could occur during a fire accident event where a robust container holding the radioactive materials ruptures catastrophically due to excessive pressurization. The common source of pressurization is the vaporization of water adsorbed onto the plutonium bearing oxides. A simplified pressure based approach derived from NUREG/CR-6410 is presented which allows calculation of airborne release fractions for pressures up to and above 500 psig. A parametric study is used to determine a bias (conservative or non-conservative) when the approach is applied to DOE-STD-3013 welded stainless steel containers which are used to store plutonium bearing oxides at the US Department of Energy Savannah River Site. The event considered is a 3013 container subjected to a hypothesized facility fire where the container fails catastrophically and ruptures resulting in a vented high pressure release of the plutonium bearing oxide materials. The parametric study shows that the simple correlation for calculating airborne release fractions is biased high by about 40% compared with the detailed NUREG/CR-6410 method. Care should be taken in using the simplified approach where the ratio of vessel net free volume to maximum allowed oxide mass is greater than 0.66 cc/g.
Research on Design Method of Hydrogen Storage Pressure Vessel in the Hydrogen Refueling Station Based on Failure Mode
Authors: Ji Fang , Jia Xiaoliang , Chen Zhiwei , Liu Cenfan , Duan Linlin
Published: October 2021

With the rapid development and industrialization of hydrogen fuel cells and electric vehicles, safe and efficient hydrogen storage technology has become the main bottleneck for the development of hydrogen energy. As an important supporting facility of hydrogen fuel cell vehicles, the hydrogen storage mode adopted by hydrogen refueling station is mainly high-pressure hydrogen storage. Hydrogen storage pressure vessel as the main core equipment of hydrogen refueling station, its storage pressure is high, the hydrogen is flammable and explosive, has the potential leakage and explosion risk, its safety is particularly important. At present, there is still a lack of relevant research on the mechanical properties of materials used in hydrogen storage vessels in high-pressure hydrogen atmosphere in China, and there are still huge safety risks in the design and calculation of hydrogen storage pressure vessels in hydrogen refueling stations. So, this paper summarizes the characteristics and typical failure modes of hydrogen storage vessels in hydrogen refueling stations, give the assessment methods for each failure mode and the test scheme for measuring the materials mechanical properties data in hydrogen atmosphere used in the failure assessment. The design method based on the failure mode for hydrogen storage pressure vessels in hydrogen refueling stations is proposed in the paper.
Effect of Parameters of Elasto-Plastic Damper on Mitigation of Connected Cabinets Storing Electronics Subjected to Seismic Waves
Authors: Shintani Atsuhiko , Yoshida Takuma , Nakagawa Chihiro , Ito Tomohiro
Published: October 2021

In this paper, the mitigation of the seismic response of connected cabinets and the electronics inside them when using elasto-plastic dampers installed between cabinets is reported. In many plants, such as power and chemical plants, several rectangular cabinets, which contain electronics, are set directly on the floor in the buildings. The electronics inside the cabinets are extremely important for controlling the behavior of the plant. When an earthquake occurs, the cabinets and inside electronics overturned by a rocking motion and may be damaged or destroyed. Even if the cabinets are not overturned, there is a concern that large accelerations will be applied to the internal electronics owing to the seismic wave. As a result, the full plant cannot be controlled, and a serious accident may occur. Therefore, it is necessary to develop methods that can simultaneously reduce rocking motion and prevent internal electronic damage. In some cases, the cabinets cannot be connected to the wall or floor for a particular reason. Even in this case, connecting the adjacent cabinets with an elasto-plastic damper, which is a nonlinear damper, can mitigate the vibrations of the cabinets and electronics. We consider the behavior of adjacent cabinets with electronics connected using two elasto-plastic dampers. The cabinets are modelled by the rigid bodies rotating around their corners, and the internal electronics are modeled as rigid bodies moving in the translational direction in the cabinets. The elasto-plastic damper has bilinear hysteretic characteristics and can absorb the energy of the earthquake inputs. The rocking behaviors of the cabinets and accelerations of the electronics are investigated when the seismic wave is input to the connecting cabinets storing the electronics. The effects of the elasto-plastic damper on the mitigation of the rocking motions of the cabinets and the accelerations of the electronics were investigated. In particular, the attachment positions of the elasto-plastic dampers are important parameters for reducing the vibrations of the cabinets and electronics. Finally, the effects of the attachment position of the elasto-plastic damper are discussed.
Fracture Analysis of Reactor Pressure Vessel Lower Head Considering Core Meltdown Accident
Authors: Dubyk Yaroslav , Antonchenko Vitalii , Zarazovskii Maksym
Published: October 2021

This paper presents fracture mechanics analysis for highly loaded reactor pressure vessel (RPV) of the WWER-440/213 unit during in-vessel core melt retention (IVMR) scenario. In-Vessel Core Melt Retention strategy via external vessel cooling is widely applied for reactors of relatively low power like WWER-440. During the IVRM a reactor pressure vessel is affected by huge thermal loading from molted core (a source of heat generation), also internal pressure may be present. To resist these loadings RPV is cooled from the outer surface by the flooding of the reactor cavity. This may lead to thermal shock conditions, as we obtain a huge temperature gradient through the RPV wall, with relative cold water on the outer surface.

The calculations were performed using global 2D RPV model and local 3D sub-model with crack embedded into mesh for J-integral evaluations. First 2D RPV model was used to calculate the global stress-strain state of the RPV. During the calculation plasticity and creep material behavior was considered, as well as melt of the fuel elements during calculation, which were ‘killed’ (excluded) when their temperature was above the melting line. Then a 3D sub-model with crack was calculated, with boundary conditions taken from the 2D axisymmetric analysis. Finally, a J-integral was evaluated according several procedures. Different crack positions are considered, as well as different crack axis ratio. Conclusions were drawn about applications of J-integral procedures for such a highly loaded scenario.
Evaluation of Hydrogen Embrittlement Behaviors in Pipeline Steel Welds Using In-Situ SP Test In High-Pressure Hydrogen Environments
Authors: Shin Hyung-Seop , Custodio N. A. , Yeo Juho , Cho Jae-Won , Baek Un-Bong , Nahm Seung-Hoon
Published: October 2021

A simple screening technique of hydrogen embrittlement (HE) of steels for hydrogen energy facilities using an in-situ small-punch (SP) test method under external hydrogen condition has been established. Using this method, we investigated the HE behaviors of API X70 steel welds under test conditions mimicking pipeline operating environments. The HE sensitivity at each region of the base metal, heat-affected zone, and weld metal of the steel weld was examined qualitatively and quantitatively and compared to one another. Under 8 MPa H2 gas, the welds showed pronounced HE: the HE behaviors induced were similar across all tested regions. This shows that the in-situ SP test is effective for screening HE susceptibility of pipeline steel welds in high-pressure hydrogen environments.
Technical Progress Review and Prospect of Safety Guarantee for Long-Term Service Hydrogenation Reactors
Authors: Xuedong Chen , Zhichao Fan , Jie Dong , Mingdong Hu , Shantung Tu , Cengdian Liu
Published: October 2021

The hydrogenation reactor is the core equipment of petrochemical hydroreforming, hydrorefining, hydrocracking and other units, which operates over long term under harsh conditions, e.g., high temperature, high pressure, hydrogen. In China, a considerable number of hydrogenation reactors have been in service for more than 20 years, and the longest service has reached 48 years. How to ensure the safe operation and reasonably extend the service life of long-term service hydrogenation reactor is an urgent engineering and technical problem. In this paper, the theoretical exploration and empirical research progress on safety guarantee of in-service hot-wall hydrogenation reactors in the past 40 years are reviewed, including failure modes, degradation mechanism of material performance, inspection and maintenance methods, safety assessment and remaining life prediction technologies, welding repair technologies, and improvement of operation process, etc. In view of the main problems existing in the safety guarantee technology of hydrogenation reactors which have been in service for more than 30 years, suggestions for further research are put forward, including establishment of a database for long-term service hydrogenation reactors (20∼50 years), development of high-precision non-destructive testing technology, research on the occurrence, development and termination laws of the potential failure mechanism of long-term service hydrogenation reactors, optimization of safety assessment technology, research on the ultimate service life assessment technology, in order to promote the technical progress of safety guarantee of hydrogenation reactors which have been in service for more than 30 years.
Functional Analysis of a HPHT Subsea Tool Under Thermal Loads
Authors: Bansal Gaurav , Sepehri Ali , Edke Mangesh
Published: October 2021

The offshore oil and gas industry continues to develop new tools that are intended to be operated in increasingly harsh environments. Stricter requirements result in more complex assemblies that are composed of multiple closely fitting components. Fluid flows at high temperatures lead to transient and non-uniform temperature distributions in tools. This can affect tool functionality which needs to be assessed with the help of numerical techniques.

The objective of this study is to evaluate the effect of thermal loads on the functionality of a valve assembly. A thermal finite element model of the assembly is developed to obtain temperature distribution everywhere in the model in transient and steady states. Temperature profiles are later mapped into structural models to obtain thermal strains at critical regions of the assembly. Thermal deformations are evaluated against internal acceptance criteria for operational functionality of the assembly.
Study on Effective Estimation of Parameters of the Herschel-Bulkley Fluid Model for Magnetorheological Fluid
Authors: Keshav Manjeet , C. Sujatha
Published: October 2021

Among different rheological models for Magnetorheological (MR) fluids, Herschel-Bulkley (H-B) fluid model is the most suitable model in explaining the characterization results. The current study presents an effective way for estimating parameters of the H-B model by considering the post-yield low shear rate data to high shear rate data where the shear-thinning effect takes place; this is termed as effective H-B model. For the comparison purpose, the linear Bingham Plastic (BP) model is fitted by projecting high shear rate data onto the y-axis and another H-B model is fitted using all characterization data. To determine the damping forces, formulation for the flow of MR fluid inside the MR valve is presented. The estimated damping forces resulting from the H-B model, BP model and effective H-B model are then compared for different magnetic fields. It was found that the H-B model overestimates the damping forces and, on the other hand, the inability of the BP model in explaining the shear-thinning effects at high shear rates lead to overestimation of damping forces and it becomes more pronounced at high piston velocities. This study may provide guidance for estimating parameters of the H-B model for accurate prediction of damping forces in the design-phase.
Comparison of Classification Machine Learning Algorithms for Damage Detection in Simulated Total Knee Replacements
Authors: Miller Brandon A. , Anton Steven R.
Published: October 2021

Total knee arthroplasty (TKA) is currently one of the most common orthopedic surgeries in the United States. While the surgery is generally highly successful, revision due to pain and failure is costly, and can have adverse impacts on patient outcomes. The possibility exists to reduce rates of catastrophic failure by early detection of damage in total knee replacements (TKR). Previous work has been done to establish the ability of a structural health monitoring (SHM) technique known as the electromechanical impedance (EMI) method to detect certain types of damage prevalent in TKRs. In the previous work, 19 simulated TKRs were constructed and artificially damaged, impedance spectrum measurements were taken, and healthy and damaged data was compared to determine if significant differences between these impedance responses exist. The current study expands upon the previous work by exploring classification machine learning (ML) techniques to translate the differences in impedance responses into discrete damage classes. The goal of this work is to determine ideal classification technique(s) for identifying and classifying damage within the aforementioned TKR systems. To this end, several algorithms are trained on the aforementioned impedance data, and the results of a leave-one-out cross-validation scheme are compared for accuracy, among other common ML performance metrics.
The impact of deep space radiation on cognitive performance: From biological sex to biomarkers to countermeasures
Authors: Krukowski Karen , Grue Katherine , Becker McKenna , Elizarraras Edward , Frias Elma S. , Halvorsen Aaron , Koenig-Zanoff McKensie , Frattini Valentina , Nimmagadda Hasitha , Feng Xi , Jones Tamako , Nelson Gregory , Ferguson Adam R. , Rosi Susanna
Published: October 2021

Space radiation affects memory in male and not in female mice, and it is dependent on the innate immune system response.
miR-1 sustains muscle physiology by controlling V-ATPase complex assembly
Authors: Gutiérrez-Pérez Paula , Santillán Emilio M. , Lendl Thomas , Wang Jingkui , Schrempf Anna , Steinacker Thomas L. , Asparuhova Mila , Brandstetter Marlene , Haselbach David , Cochella Luisa
Published: October 2021

A deeply conserved miR-1–dependent regulon of mitochondria and lysosome function is essential for muscle physiology.
Molecular ruler mechanism and interfacial catalysis of the integral membrane acyltransferase PatA
Authors: Anso Itxaso , Basso Luis G. M. , Wang Lei , Marina Alberto , Páez-Pérez Edgar D. , Jäger Christian , Gavotto Floriane , Tersa Montse , Perrone Sebastián , Contreras F.-Xabier , Prandi Jacques , Gilleron Martine , Linster Carole L. , Corzana Francisco , Lowary Todd L. , Trastoy Beatriz , Guerin Marcelo E.
Published: October 2021

The integral membrane acyltransferase PatA uses a molecular ruler mechanism for acyl chain length recognition and transfer.
Paleomagnetic evidence for a disk substructure in the early solar system
Authors: Borlina Cauê S. , Weiss Benjamin P. , Bryson James F. J. , Bai Xue-Ning , Lima Eduardo A. , Chatterjee Nilanjan , Mansbach Elias N.
Published: October 2021

Paleomagnetic measurements of chondrules indicate the presence of a substructure in the solar nebula.
Mars lander spies the planet's deep boundaries
Authors: Voosen Paul
Published: October 2021

Despite lack of large quakes, InSight team fixes size of crust, mantle, and core.
LGBTQ researchers say they want to be counted
Authors: Langin Katie
Published: October 2021

Scientists call for National Science Foundation's workforce surveys to tally sexual and gender minorities.
Runners-up
Authors: Service Robert F. , Kaiser Jocelyn , Voosen Paul , Clery Daniel , Price Michael , Langin Katie , Cohen Jon , Service Robert F. , Pennisi Elizabeth
Published: October 2021

Science
 has named nine scientific advances as runners-up for the 2020 Breakthrough of the Year.
2020 AAAS Kavli Science Journalism Award winners
Authors: Lane Earl , Hughes Emily
Published: October 2021

Entries feature reporting on topics ranging from Ebola to the global COVID-19 pandemic
The G protein signaling regulator RGS3 enhances the GTPase activity of KRAS
Authors: Li Chuanchuan , Vides Alberto , Kim Dongsung , Xue Jenny Y. , Zhao Yulei , Lito Piro
Published: October 2021

Paving the way for KRAS inhibitors

KRAS is a key oncogene in multiple cancer types, but existing inhibitors target only a mutant form of KRAS containing the G12C mutation, and their function presents a mechanistic conundrum. It is known that KRAS
G12C
inhibitors bind to the oncoprotein in its inactive form; however, KRAS mutations such as G12C interfere with the action of proteins that normally help it hydrolyze GTP to achieve the inactive state. Li
et al
. have now identified a protein that enhances GTP hydrolysis by mutant KRAS, helping to explain the clinical activity of current drugs targeting this oncoprotein (see the Perspective by Cox and Der). —YN
Adding cognitive connections to the cerebellum
Authors: Hatten Mary E.
Published: October 2021

During evolution, duplication of subnuclei generates broader cerebellar projections
A gatekeeper for learning
Authors: Donato Flavio
Published: October 2021

During associative learning, the perirhinal cortex controls burst firing of sensory neurons
Chelated electrolytes for divalent metal ions
Authors: Zuo Pengjian , Yin Geping
Published: October 2021

Chelating electrolytes reorganize ion solvation and enable reversible magnesium batteries
Pathways to tough yet soft materials
Authors: Bosnjak Nikola , Silberstein Meredith N.
Published: October 2021

Chemical and physical strategies allow polymer chains in hydrogels to extend or slip
The infectious diseases that shaped us
Plagues Upon the Earth
Kyle Harper
Princeton University Press, 2021. 704 pp.
Authors: Morgan Gregory J.
Published: October 2021

An ambitious history traces humanity’s entanglements with communicable illness
Revisiting brain stimulation in Parkinson’s disease
Authors: Haas Carola A.
Published: October 2021

Electrical burst stimulation rescues movement effectively in parkinsonian mice
A Decade for restoring Earth
Authors: Strassburg Bernardo B. N.
Published: October 2021

Next week, the United Nations Biodiversity Conference (COP 15) convenes in Kunming, China, to discuss a new global plan to conserve nature and improve the sharing of its benefits across humankind. If such a plan is successfully implemented, it will mark a turning point in the millennia-long decline of the natural world due to human activity. This prospect has been boosted by the United Nations General Assembly decision to declare 2021–2030 as the Decade of Ecosystem Restoration (the “Decade”), which aims to prevent, halt, and reverse the degradation of ecosystems across the planet.
The fault in our stars
Authors: Sokol Joshua
Published: October 2021

Satellite swarms are threatening the night sky. Is low-Earth orbit the next great crucible of environmental conflict?
In Science Journals
Authors: Xie Shang-Ping , Suleymanov Yury , Zahn Laura M. , Grocholski Brent , Osborne Ian S. , Isles Hannah M. , Lavine Marc S. , Scanlon Seth Thomas , Kelly Priscilla N. , Funk Michael A. , VanHook Annalisa M. , Czajka Caitlin , Ray L. Bryan , Stern Peter , Nusinovich Yevgeniya , Sugden Andrew M.
Published: October 2021

Highlights from the
Science
family of journals
Pandemic enters transition phase—but to what?
Authors: Kupferschmidt Kai
Published: October 2021

High vaccination rates in some countries may soon make COVID-19 an “endemic” disease
Asteroid tour could reveal Solar System’s chaotic origin
Authors: Voosen Paul
Published: October 2021

NASA’s Lucy mission will survey Jupiter’s Trojans, thought to have been swept up by migrating gas giants
Stepping down, NIH director says it’s time for ‘new vision’
Authors: Kaiser Jocelyn
Published: October 2021

Navigating rough political waters and a pandemic, Francis Collins greatly expanded biomedical research agency
Spatial bias in cAMP generation determines biological responses to PTH type 1 receptor activation
Authors: White Alex D. , Peña Karina A. , Clark Lisa J. , Maria Christian Santa , Liu Shi , Jean-Alphonse Frédéric G. , Lee Ji Young , Lei Saifei , Cheng Zhiqiang , Tu Chia-Ling , Fang Fei , Szeto Nicholas , Gardella Thomas J. , Xiao Kunhong , Gellman Samuel H. , Bahar Ivet , Sutkeviciute Ieva , Chang Wenhan , Vilardaga Jean-Pierre
Published: October 2021

Physiological responses to parathyroid hormone depend on the subcellular location of receptor activity.
Improving IL-2 for T cell therapy
Authors: Baek Amy E.
Published: October 2021

An IL-2 partial agonist that avoids the terminal differentiation of T cells enhances their antitumor activity.
A Single Nucleotide Change in the
polC
DNA Polymerase III in Clostridium thermocellum Is Sufficient To Create a Hypermutator Phenotype
Authors: Lanahan Anthony , Zakowicz Kamila , Tian Liang , Olson Daniel G. , Lynd Lee R.
Published: October 2021

Cellulosic biofuels are a promising approach to decarbonize the heavy-duty-transportation sector. A longstanding barrier to cost-effective cellulosic biofuel production is the recalcitrance of the material to solubilization.
The Rare, the Best: Spread of Antimalarial-Resistant Plasmodium falciparum Parasites by
Anopheles
Mosquito Vectors
Authors: Berry Antoine , Menard Sandie , Nsango Sandrine E. , Abate Luc , Concordet Didier , Tchioffo Tsapi Majoline , Iriart Xavier , Awono-Ambéné Parfait H. , Roche Benjamin , Morlais Isabelle
Published: October 2021

Drug selection pressure in malaria patients is the cause of the emergence of resistant parasites. Resistance imposes a fitness cost for parasites in untreated infections, so withdrawal of the drug leads to the return of susceptible parasites.
Intraepithelial growth pattern for eyelid sebaceous carcinoma: a cohort of 214 patients from a single institution
Authors: Zhou Chuandi , Chai Peiwei , Xia Wenwen , Li Jiang , Jia Renbing , Fan Xianqun
Published: October 2021

Aims

To determine the distribution of three different intraepithelial growth patterns (pagetoid, bowenoid and papillary) in eyelid sebaceous carcinoma (SC) and correlate them with the clinical characteristics and prognosis.

Methods

A retrospective cohort study. The medical charts and pathological sections were retrospectively reviewed. All eligible patients were followed up for recurrence, metastasis and tumour-related mortality. The clinical significance of each intraepithelial growth pattern was determined by Cox regression.

Results

Of the 214 patients, 67 (31%) presented with intraepithelial invasion, among them, 34 (16%) were pagetoid, 27 (13%) were bowenoid and 6 (2.8%) were papillary. Patients of pagetoid intraepithelial spread showed significantly longer diagnostic delay (p=0.001) and more initial misdiagnoses of blepharitis (p=0.035). After a median follow-up period of 34.0 months, 67 (46%) patients in the non-intraepithelial group, 17 (50%) in the pagetoid group, 8 (30%) in the bowenoid group and 2 (33%) in the papillary group recurred. And 30 (20%) patients in the non-intraepithelial group, 9 (27%) in the pagetoid group and 4 (15%) in the bowenoid group developed metastasis. Moreover, 15 (10%) patients in the non-intraepithelial group, 6 (18%) in the pagetoid group and 1 (3.7%) in the bowenoid group died of SC. Cox regression indicated that pagetoid intraepithelial growth pattern was remarkably associated with increased chances of tumour-related mortality (HR=2.95, 95% CI 1.14 to 7.64, p=0.026).

Conclusions

Intraepithelial tumour invasion was presented in nearly one third of patients with eyelid SC. Pagetoid intraepithelial neoplasia, the predominant growth pattern, significantly increased the risk of tumour-related mortality. Meticulous histopathological intraepithelial examination is recommended for every patient of eyelid SC. Special attention should be paid to those with pagetoid invasion, who may require more intensive managements.
Heat illness experience at BMH Shaibah, Basra, during Operation TELIC: May–July 2003
Authors: Coleman Jamie , Fair S , Doughty H , Stacey M J
Published: October 2021

This is an observational study of heat-related illness in UK Service Personnel deployed into summer conditions in Northern Kuwait and Southern Iraq. Among 622 hospitalisations reported during a 9-week period at the historical British Military Hospital, Shaibah, 303 consecutive admissions are reviewed in detail. Several clinical syndromes attributable to thermal stress were observed. These ranged from self-limiting debility to life-threatening failures of homeostasis, with 5.0% developing a critical care requirement. Hyponatraemia was a commonly occurring electrolyte disturbance by which, relative to the local reference range, a majority of heat-attributed admissions were affected. Reductions in measured serum sodium could be profound (<125 mmol/L in 20.1% of all heat-related casualties). Hypokalaemia was observed in half of cases, though only a minority were affected by severely low potassium (<2.5 mmol/L in 4.0%). Despite preventive measures prescribed on hospital discharge, illness and significant biochemical derangements could recur upon return to duties in the heat. We reiterate the need for primary prevention of heat illness wherever possible and importance of early, effective interventions to treat and protect Service Personnel from secondary injury. We also highlight the requirement for comprehensive assessment to inform prognostication and occupational decision-making in relation to extreme climatic heat, including aeromedical evacuation. We draw additional attention to the contribution of psychological factors in select cases and identify research questions to improve understanding of environment-induced incapacitation in general.
Energy-Efficient Computation Offloading for UAV-Assisted MEC: A Two-Stage Optimization Scheme
Authors: Lin Weiwei , Huang Tiansheng , Li Xin , Shi Fang , Wang Xiumin , Hsu Ching-Hsien
Published: October 2021

In addition to the stationary
mobile edge computing (MEC)
servers, a few MEC surrogates that possess a certain mobility and computation capacity, e.g., flying
unmanned aerial vehicles (UAVs)
and private vehicles, have risen as powerful counterparts for service provision. In this article, we design a two-stage online scheduling scheme, targeting computation offloading in a UAV-assisted MEC system. On our stage-one formulation, an online scheduling framework is proposed for dynamic adjustment of mobile users' CPU frequency and their transmission power, aiming at producing a socially beneficial solution to users. But the major impediment during our investigation lies in that users might not unconditionally follow the scheduling decision released by servers as a result of their individual rationality. In this regard, we formulate each step of online scheduling on stage one into a non-cooperative game with potential competition over the limited radio resource. As a solution, a centralized online scheduling algorithm, called ONCCO, is proposed, which significantly promotes social benefit on the basis of the users' individual rationality. On our stage-two formulation, we are working towards the optimization of UAV computation resource provision, aiming at minimizing the energy consumption of UAVs during such a process, and correspondingly, another algorithm, called WS-UAV, is given as a solution. Finally, extensive experiments via numerical simulation are conducted for an evaluation purpose, by which we show that our proposed algorithms achieve satisfying performance enhancement in terms of energy conservation and sustainable service provision.
A Deep Learning Approach for Voice Disorder Detection for Smart Connected Living Environments
Authors: Verde Laura , Brancati Nadia , De Pietro Giuseppe , Frucci Maria , Sannino Giovanna
Published: October 2021

Edge Analytics and Artificial Intelligence are important features of the current smart connected living community. In a society where people, homes, cities, and workplaces are simultaneously connected through various devices, primarily through mobile devices, a considerable amount of data is exchanged, and the processing and storage of these data are laborious and difficult tasks. Edge Analytics allows the collection and analysis of such data on mobile devices, such as smartphones and tablets, without involving any cloud-centred architecture that cannot guarantee real-time responsiveness. Meanwhile, Artificial Intelligence techniques can constitute a valid instrument to process data, limiting the computation time, and optimising decisional processes and predictions in several sectors, such as healthcare. Within this field, in this article, an approach able to evaluate the voice quality condition is proposed. A fully automatic algorithm, based on Deep Learning, classifies a voice as healthy or pathological by analysing spectrogram images extracted by means of the recording of vowel /a/, in compliance with the traditional medical protocol. A light Convolutional Neural Network is embedded in a mobile health application in order to provide an instrument capable of assessing voice disorders in a fast, easy, and portable way. Thus, a straightforward mobile device becomes a screening tool useful for the early diagnosis, monitoring, and treatment of voice disorders. The proposed approach has been tested on a broad set of voice samples, not limited to the most common voice diseases but including all the pathologies present in three different databases achieving F1-scores, over the testing set, equal to 80%, 90%, and 73%. Although the proposed network consists of a reduced number of layers, the results are very competitive compared to those of other “cutting edge” approaches constructed using more complex neural networks, and compared to the classic deep neural networks, for example, VGG-16 and ResNet-50.
Automated Discovery of Network Cameras in Heterogeneous Web Pages
Authors: Dailey Ryan , Chawla Aniesh , Liu Andrew , Mishra Sripath , Zhang Ling , Majors Josh , Lu Yung-Hsiang , Thiruvathukal George K.
Published: October 2021

Reduction in the cost of Network Cameras along with a rise in connectivity enables entities all around the world to deploy vast arrays of camera networks. Network cameras offer real-time visual data that can be used for studying traffic patterns, emergency response, security, and other applications. Although many sources of Network Camera data are available, collecting the data remains difficult due to variations in programming interface and website structures. Previous solutions rely on manually parsing the target website, taking many hours to complete. We create a general and automated solution for aggregating Network Camera data spread across thousands of uniquely structured web pages. We analyze heterogeneous web page structures and identify common characteristics among 73 sample Network Camera websites (each website has multiple web pages). These characteristics are then used to build an automated camera discovery module that crawls and aggregates Network Camera data. Our system successfully extracts 57,364 Network Cameras from 237,257 unique web pages.