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导弹与航天运载技术(中英文) 1979年第6期 91-133页

作者： Coleman J bryan john f 徐雪英汪夭汉

本文对十二种材料在液氧、增压液氧及高压气氧中的反应活性进行了评述。这些材料包括;铝合金(6061-T6)、聚四氟乙烯、四种填充聚四氟乙烯、聚酰亚胺、聚三氟氯乙烯、两种氟弹性体、全氟醚基润滑脂及尼龙聚合物。

关键词：气氧靶场白沙试验场机械冲击试验反应次数牛顿试样直径试验次数泰氟隆液化气体液氧肯尼迪宇宙敏感性

Telomeric DNA breaks in human induced pluripotent stem cells trigger ATR-mediated arrest and telomerase-independent telomere damage repair

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Journal of Molecular Cell Biology 2024年第3期16卷 46-60页

作者： Katrina N.Estep john W.Tobias Rafael J.fernandez Brinley M.Beveridge f.Brad johnson Department of Pathology and Laboratory Medicine University of PennsylvaniaPhiladelphiaPA 19104USA Quantiative Biosciences Merck&Co.Inc.West PointPA 19486USA Penn Genomic Analysis Core University of PennsylvaniaPhiladelphiaPA 19104USA

Although mechanisms of telomere protection are well-defined in differentiated cells,how stem cells sense and respond to telomere dysfunction,in particular telomeric double-strand breaks(DSBs),is poorly ***,we report the DNA damage signaling,cell cycle,and transcriptome changes in human induced pluripotent stem cells(iPSCs)in response to telomere-internal *** engineer human iPSCs with an inducible TRf1-fokI fusion protein to acutely induce DSBs at *** this model,we demonstrate that TRf1-fokI DSBs activate an ATR-dependent DNA damage response,which leads to p53-independent cell cycle arrest in *** CRISPR–Cas9 to cripple the catalytic domain of telomerase reverse transcriptase,we show that telomerase is largely dispensable for survival and lengthening of TRf1-fokI-cleaved telomeres,which instead are effectively repaired by robust homologous recombination(HR).In contrast to HR-based telomere maintenance in mouse embryonic stem cells,where HR causes ZSCAN4-dependent extension of telomeres beyond their initial lengths,HR-based repair of telomeric breaks is sufficient to maintain iPSC telomeres at a normal length,which is compatible with sustained survival of the cells over several days of TRf1-fokI *** findings suggest a previously unappreciated role for HR in telomere maintenance in telomerase-positive iPSCs and reveal distinct iPSC-specific responses to targeted telomeric DNA damage.

关键词： telomeres telomerase alternative lengthening of telomeres pluripotent stem cells DNA damage double-strand breaks

Boron neutron capture therapy of cancer:where do we stand now?

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Cancer Communications 2024年第8期44卷 889-892页

作者： Rolf f.Barth Gong Wu Maria da Graca H.Vicente john C Grecula Nilendu Gupta Department of Pathology The Ohio State UniversityColumbusOhioUSA Mass Spectrometry and Proteomics facility The Ohio State UniversityColumbusOhioUSA Department of Chemistry Louisiana State UniversityBaton RougeLouisianaUSA Department of Radiation Oncology The Ohio State UniversityColumbusOhioUSA

1 INTRODUCTION,This is the third Editorial/Commentary that one of us(***)has written relating to boron neutron capture therapy(BNCT)[1,2].for those readers who are unfamiliar with BNCT we would refer them to several recent comprehensive reviews[3–5].The second Editorial ended on a hopeful note that with the introduction of acceleratorbased neutron sources(ABNSs),BNCT would enter into the mainstream of radiation therapy[2].

关键词： boron 1,2 neutron

Transformer for the Design of Automatic Control Systems with Prefilters

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World Journal of Engineering and Technology 2024年第3期12卷 575-586页

作者： Isaac Hughes john f. O’Brien Department of Electrical Engineering and Computer Science University of Wyoming Laramie USA

A machine learning model, using the transformer architecture, is used to design a feedback compensator and prefilter for various simulated plants. The output of the transformer is a sequence of compensator and prefilter parameters. The compensator and prefilter are linear models, preserving the ability to analyze the system with linear control theory. The input to the network is a window of recent reference and output samples. The goal of the transformer is to minimize tracking error at each time step. The plants under consideration range from simple to challenging. The more difficult plants contain closely spaced, lightly damped, complex conjugate pairs of poles and zeros. Results are compared to PID controllers tuned for a similar crossover frequency and optimal phase margin. for simple plants, the transformer converges to solutions which overly rely on the prefilter, neglecting the maximization of negative feedback. for more complex plants, the transformer designs a compensator and prefilter with more desirable qualities. In all cases, the transformer can start with random model parameters and modify them to minimize tracking error on the step reference.

关键词： feedback Machine Learning Compensator Design

Artificial light at night(ALAN) pollution alters bat lunar chronobiology:insights from broad-scale long-term acoustic monitoring

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Ecological Processes 2024年第1期13卷 176-187页

作者： Han Li Pauline Allen Saige Boris Samantha Lagrama Jade Lyons Christina Mills Pauline Moussi Casey Nichols Carter Tacosik Mc Kenzie Tsaousis Nyzaya Livingston Wilson john f.Grider Kevin A.Parker Matina C.Kalcounis-Rueppell Department of Biology University of Nebraska Omaha Department of Biology University of North Carolina Greensboro Colorado Parks and Wild-life Parker Ecology LLC Department of Biological Sciences University of Alberta

Background The timing of behavior and habitat use of nocturnal animals can be influenced by the lunar cycle in nature. The prevalence of artificial light at night(ALAN) has been recognized as a source of environmental pol-lution. The interaction between ALAN and the lunar cycle on bat behavior is important for understanding anthro-pogenic effects on bats. We utilized a decade(2012–2022) of acoustic monitoring data collected in North Carolina, United States, to investigate the relationship between bat activity, lunar cycle, and light pollution. We examined whether the amount of lunar illumination affected species-specific nightly activity and whether hourly bat activity patterns varied between nights with different moon phases. We further investigated if the relationship between bat activity and the lunar cycle might be altered by light *** We found that seven bat species showed activity variation across nights in relation to the amount of moon illumination when ALAN was absent. In general, bats were less active on full moon nights compared to new moon nights. Light pollution interacted with the bat–lunar relationship in five of the seven species, masking the effect of the lunar cycle. We identified delayed bat activity patterns on nights with a full or waxing moon in seven species, and light pollution altered that pattern in four species. Overall, ALAN was associated with decreased bat activity inde-pendent of lunar cycle *** Our study demonstrated that at a broad spatial scale, ALAN negatively affected many North American temperate bat species and altered their lunar chronobiology. As light pollution is spreading to historically dark areas and habitats, ALAN might couple with other threats, such as the white-nose syndrome or climate change, to cause cascading damage in the environment that depends on ecosystem services such as pest control provided by bats. We argue that further research and conservation actions are needed to mitigate

关键词： Artificial light at night ALAN Bats Chiroptera Chronobiology Light pollution Lunar cycle Moonlight

Managerial perspectives of scaling up robotic-assisted surgery in healthcare systems:A systematic literature review

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Laparoscopic, Endoscopic and Robotic Surgery 2024年第3期7卷 113-122页

作者： Ravichandran Anitha Komattu Chacko john Gnanadhas Jabarethina Sri Ramachandra faculty of Management Sciences Sri Ramachandra Institute of Higher Education and Research(Category-I Deemed to be University)ChennaiIndia

Objectives Robotic-assisted surgery(RAS)is a minimally invasive technique practiced in multiple *** training is essential for the acquisition of RAS *** cost of RAS is considered to be high,which makes it a burden for institutes and unaffordable for *** systematic literature review(SLR)focused on the various RAS training methods applied in different surgical specialties,as well as the cost elements of RAS,and was to summarize the opportunities and challenges associated with scaling up *** An SLR was carried out based on the Preferred Reporting Items for Systematic reviews and Meta-Analyses reporting *** PubMed,EBSCO,and Scopus databases were searched for reports from January 2018 through January ***-text reviews and research articles in the English language from Asia-Pacific countries were *** that outlined training and costs associated with RAS were *** The most common training system is the da Vinci *** simulation technique,which includes dry-lab,wet-lab,and virtual reality training,was found to be a common and important *** cost of RAS encompasses the installation and maintenance costs of the robotic system,the operation theatre rent,personnel cost,surgical instrument and material cost,and other miscellaneous *** synthesis of SLR revealed the challenges and opportunities regarding RAS training and *** The results of this SLR will help stakeholders such as decision-makers,influencers,and end users of RAS to understand the significance of training and cost in scaling up RAS from a managerial *** any healthcare innovation to reach a vast population,cost-effectiveness and standard training are crucial.

关键词： da Vinci system Healthcare Robotic-assisted surgery Robotic surgery Robotic training Robotic surgery cost

What diameter?What height?Influence of measures of average tree size on area-based allometric volume relationships

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forest Ecosystems 2024年第1期11卷 100-109页

作者： Yilin Wang john A.Kershaw Mark J.Ducey Yuan Sun James B.McCarter Integrated forest Mensuration and Systems Analysis Laboratory Faculty of Forestry and Environmental ManagementUniversity of New BrunswickFrederictonNBCanada Department of Natural Resources and the Environment University of New HampshireDurhamNHUSA College of forestry Nanjing Forestry UniversityNanjing210037China Scientific Programmer RayonierYuleeFLUSA

Volume is an important attribute used in many forest management *** from 83 fixed-area plots located in central New Brunswick,Canada,are used to examine how different measures of stand-level diameter and height influence volume prediction using a stand-level variant of Honer's(1967)volume *** density was included in the models(Volume=f(Diameter,Height,Density))choice of diameter measure was more important than choice of height *** density was not included(Volume=f(Diameter,Height)),the opposite was *** models with density included,moment-based estimators of stand diameter and height performed better than all other *** models without density,largest tree estimators of stand diameter and height performed better than other *** overall best equation used quadratic mean diameter,Lorey's height,and density(root mean square error=5.26 m^3·ha^(-1);1.9%relative error).The best equation without density used mean diameter of the largest trees needed to calculate a stand density index of 400 and the mean height of the tallest 400 trees per ha(root mean square error=32.08 m^(3)·ha^(-1);11.8%relative error).The results of this study have some important implications for height subsampling and LiDAR-derived forest inventory analyses.

关键词： Allometric relationships Stand structure Volume estimation Stand-level attributes

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Effect of cinnamaldehyde on Rhizopus stolonifer and on the conservation of sweet potato

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food Quality and Safety 2024年第1期8卷 212-225页

作者：陈晨薛智超 Penta Pristijono john B.Golding 陈刚李永新杨虎清 College of food and Health Zhejiang A&F UniversityHangzhouChina Zhejiang Provincial Key Laboratory of Resources Protection and Innovation of Traditional Chinese Medicine Zhejiang A&F UniversityHangzhouChina School of Environmental and Life Sciences University of NewcastleOurimbahNSWAustralia NSW Department of Primary Industries OurimbahNSWAustralia

Objectives:Rhizopus stolonifer,which causes soft rot of sweet potato,has resulted in substantial loss of economy *** and Methods:The antifungal effect and mechanism of cinnamaldehyde(CIN)against *** were explored by biochemical analysis and RNA-sequencing in this research,and the edible quality of CIN-treated sweet potato was ***:The results showed that CIN inhibited the growth of *** and reduced the incidence of soft rot in sweet potato at a minimum inhibitory concentration of 1000μL/*** damage of the cell walls of *** by CIN was associated with the upregulation of *** leakage and malondialdehyde content increased following CIN-treatment,which was correlated with increased reactive oxygen species levels and decreased catalase *** of ERG genes and oxidative stress-related genes following CIN treatment was associated with impaired cell membrane *** mitochondrial structure of *** was damaged by CIN treatment resulting in decreased respiration rates and ATP production,which was correlated with lower expression levels of IDH1,COX4,and ***:Our research suggests that the inhibition of CIN on *** was related to the disruption of its normal gene expression network,and CIN maintained the nutritional and edible quality of sweet *** study provides valuable insights into the antifungal mechanism of CIN on *** and the maintenance of root quality,which contributes to the effcient use of CIN for controlling soft rot in sweet potato.

关键词： Ipomoea batatas soft rot cinnamaldehyde antifungal mechanism transcriptome

Assessment of the performance of the TOPGNSS and ANN-MB antennas for ionospheric measurements using low-cost u-blox GNSS receivers

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Geodesy and Geodynamics 2024年第3期15卷 291-301页

作者： Daniel Okoh Aderonke Obafaye Oluwakemi Dare-Idowu Babatunde Rabiu Anton Kashcheyev Claudio Cesaroni john Bosco Habarulema Bruno Nava United Nations African Regional Centre for Space Science and Technology Education-English(UN-ARCSSTE-E) Obafemi Awolowo University CampusIle IfeNigeria National Institute for Geophysics and Volcanology(INGV) 00143 RomeItaly Institute for Space Science and Engineering African University of Science and TechnologyAbujaNigeria University of New Brunswick FrederictonCanada South African National Space Agency(SANSA) P.O Box 32Hermanus 7200South Africa Department of Physics and Electronics Rhodes University6140 MakhandaSouth Africa The Abdus Salam International Centre for Theoretical Physics Strada Costiera11I-34151 TriesteItaly

Low-cost GNSS receivers have recently been gaining reliability as good candidates for ionospheric studies. In line with these gains are genuine concerns about improving the performance of these receivers. In this work, we present a comprehensive investigation of the performances of two antennas(the u-blox ANN-MB and the TOPGNSS TOP-106) used on a low-cost GNSS receiver known as the u-blox ZED-f9P. The two antennas were installed on two identical and co-located u-blox receivers. Data used from both receivers cover the period from January to June 2022. Results from the study indicate that the signal strengths are dominantly greater for the receiver with the TOPGNSS antenna than for the receiver with the ANN-MB antenna, implying that the TOPGNSS antenna is better than the ANN-MB antenna in terms of providing greater signal strengths. Summarily, the TOPGNSS antenna also performed better in minimizing the occurrence of cycle slips on phase TEC measurements. There are no conspicuous differences between the variances(computed as 5-min standard deviations) of phase TEC measurements for the two antennas, except for a period around May-June when the TOPGNSS gave a better performance in terms of minimizing the variances in phase TEC. Remarkably, the ANN-MB antenna gave a better performance than the TOPGNSS antenna in terms of minimizing the variances in pseudorange TEC for some satellite observations. for precise horizontal(North and East) positioning, the receiver with the TOPGNSS antenna gave better results, while the receiver with the ANN-MB antenna gave better vertical(Up) positioning. The errors for the receivers of both antennas are typically within about 5 m(the monthly mean was usually smaller than 1 m) in the horizontal direction and within about 10 m(the monthly mean was usually smaller than 4 m) in the vertical direction.

关键词： GNSS Ionosphere Low-cost Antenna TOPGNSS U-blox

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Proof of Concept for a Twin Prime Number Universe Using Set Theory

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American Journal of Computational Mathematics 2024年第3期14卷 305-317页

作者： john R. Crary Independent Researcher Lake Zurich IL USA

The fine Structure Constant (efSC) Model attempts to give a classical definition to a magical number that underlies much of quantum physics. The fine Structure Constant (α) value equal to 137.03599206 represents a dimensionless constant that characterizes the strength of the electromagnetic (EM) interaction between subatomic charged particles. Python-generated property counts for the twin prime force f{139/137} show that the adjusted ratio gives a value of α = 137.036. This implies a mathematical framework underlying this constant is based on twin prime numbers and set theory. This study attempts to demonstrate a proof of concept that a hierarchy of fractional twin prime (αII) forces replicates the quantum nature of the universe and is aligned with the Standard Model of Particle Physics. An expanded efSC Model demonstrates that twin prime forces and their property sets are mathematically viable substitutes for nuclear reactions, as demonstrated for the Beta-minus decay of neutrons into protons. Most significantly, the positive and negative prime numbers define these nuclear reactants and products as positive or negatively charged ions. furthermore, the efSC Model provides new insights regarding the hierarchy of EM forces underlying the quantum nature of the universe.

关键词： fine Structure Constant (α) Prime Numbers Set Theory Conceptual Model Quantum Physics Light and Matter Beta-Minus Decay