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A product version of the Hilton-Milner-frankl theorem

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Science China Mathematics 2024年第2期67卷 455-474页

作者： peter frankl Jian Wang Alfréd Rényi Institute of Mathematics Hungarian Academy of SciencesBudapest H-1053Hungary Department of Mathematics Taiyuan University of TechnologyTaiyuan 030024China

Two families f and G of k-subsets of {1, 2,..., n} are called non-trivial cross t-intersecting if|f ∩ G|≥t for all f ∈ f, G ∈ G and | ∩ {f : f ∈ f}| < t, | ∩ {G : G ∈ G}| < t. In the present paper,we determine... 详细信息

Two families f and G of k-subsets of {1, 2,..., n} are called non-trivial cross t-intersecting if|f ∩ G|≥t for all f ∈ f, G ∈ G and | ∩ {f : f ∈ f}| f the sizes of two non-trivial cross t-intersecting families of k-subsets of{1, 2,..., n} for n≥4(t + 2)2k2, k≥5, which is a product version of the Hilton-Milner-frankl theorem.

关键词： extremal set theory cross t-intersecting family product version non-trivial

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地球演化历史中氧逸度变化对壳幔循环启动、风化和超大陆循环的指示

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Science Bulletin 2024年第1期69卷 97-102页

作者：王瑞邬绍宸 Roberto f.Weinberg William J.Collins peter A.Cawood State Key Laboratory of Geological Processes and Mineral Resources Institute of Earth SciencesChina University of GeosciencesBeijing 100083China frontiers Science Center for Deep-time Digital Earth China University of Geosciences(Beijing)Beijing 100083China School of Earth Atmosphere and EnvironmentMonash UniversityClayton VIC 3800Australia The Institute for Geoscience Research Curtin UniversityPerth WA 6102Australia

We apply a zircon redox index to a global compilation of detrital zircons to track the variation of oxidation state,expressed asΔfMQ,through Earth's *** from I-type rocks,which comprise mantle and crustal igneous protoliths,including tonalite–trondhjemite–granodiorites(TTGs),generally have a high oxidation state(ΔfMQ>0).In contrast,zircons from igneous rocks derived from supracrustal source rocks(S-type)are commonly reduced(ΔfMQfunction derived from the Gaussian-Kernel-Density-Estimation,we use the maximum likelihood estimation(MLE)to distinguish Stype from I-type zircons through Earth's history using zircon *** S-type magma production shows a ca.600 Ma cyclicity that is closely related to the supercontinent *** link a cyclic drop in redox values after 2.6 Ga to periodic S-type magma generation associated with burial and melting of metasedimentary rocks during supercontinent assembly and ***ΔfMQ of the detrital zircons rise at~3.5 Ga followed by a consistent averageΔfMQ>0 over the last 3 *** that the redox state of magmas is independent of crustal thickness and silica variation,and elevated values are likely more closely related to tectonic setting,we suggest that the consistent averageΔfMQ>0 from ca.3.5 Ga onwards relates to recycling of oceanic lithosphere back into the mantle in what eventually became established as subduction *** more reduced magmas associated with sedimentary sources,became established at 2.6 Ga,presumably in response to continental rocks rising above sealevel,and follow peaks of productivity associated with the supercontinent cycle.

关键词： Oxidation state Supercontinent Weathering Subduction Zircon Granite

A Survey on Sensor-and Communication-Based Issues of Autonomous UAVs

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Computer Modeling in Engineering & Sciences 2024年第2期138卷 1019-1050页

作者： Pavlo Mykytyn Marcin Brzozowski Zoya Dyka peter Langendoerfer IHP-Leibniz-Institut für Innovative Mikroelektronik Wireless SystemsFrankfurt(Oder)15236Germany BTU Cottbus-Senftenberg Faculty 1:MINTCottbus03046German

The application field for Unmanned Aerial Vehicle (UAV) technology and its adoption rate have been increasingsteadily in the past years. Decreasing cost of commercial drones has enabled their use at a scale broader thanever before. However, increasing the complexity of UAVs and decreasing the cost, both contribute to a lack ofimplemented securitymeasures and raise new security and safety concerns. for instance, the issue of implausible ortampered UAV sensor measurements is barely addressed in the current research literature and thus, requires moreattention from the research community. The goal of this survey is to extensively review state-of-the-art literatureregarding common sensor- and communication-based vulnerabilities, existing threats, and active or passive cyberattacksagainst UAVs, as well as shed light on the research gaps in the literature. In this work, we describe theUnmanned Aerial System (UAS) architecture to point out the origination sources for security and safety *** the coverage and completeness of each related research work in a comprehensive comparison table as wellas classify the threats, vulnerabilities and cyber-attacks into sensor-based and communication-based ***, for each individual cyber-attack, we describe existing countermeasures or detectionmechanisms andprovide a list of requirements to ensureUAV’s security and *** also address the problem of implausible sensormeasurements and introduce the idea of a plausibility check for sensor data. By doing so, we discover additionalmeasures to improve security and safety and report on a research niche that is not well represented in the currentresearch literature.

关键词： Unmanned aerial vehicle unmanned aerial system cyber security and privacy drone swarm security vulnerabilities cyber-threats cyber-attacks plausibility check

Identific tion of quantitative trait loci and associated candidate genes for pregnancy success in Angus–Brahman crossbred heifers

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Journal of Animal Science and Biotechnology 2024年第1期15卷 162-170页

作者： Quinn A.Hoorn Gabriel A.Zayas Eduardo E.Rodriguez Laura M.Jensen Raluca G.Mateescu peter J.Hansen Department of Animal Sciences Donald Henry Barron Reproductive and Perinatal Biology Research Programand the Genetics InstituteUniversity of FloridaGainesvilleFLUSA School of Applied Systems Biology La Trobe UniversityBundooraVIC 3083Australia

Background In beef cattle, more than 50% of the energy input to produce a unit of beef is consumed by the female that produced the calf. Development of genomic tools to identify females with high genetic merit for reproductive function could increase the profitability and sustainability of beef *** Genome-wide association studies(GWAS) were performed using a single-step genomic best linear unbiased prediction approach on pregnancy outcome traits from a population of Angus–Brahman crossbred heifers. furthermore, a validation GWAS was performed using data from another farm. Heifers were genotyped with the Bovine GGP f250 array that contains 221,077 SNPs. In the discovery population, heifers were bred in winter breeding seasons involving a single round of timed artificial insemination(AI) followed by natural mating for 3 months. Two phenotypes were analyzed: pregnancy outcome to first-service AI(PAI;n = 1,481) and pregnancy status at the end of the breeding season(PEBS;n = 1,725). The heritability was estimated as 0.149 and 0.122 for PAI and PEBS, respectively. In the PAI model, one quantitative trait locus(QTL), located between 52.3 and 52.5 Mb on BTA7, explained about 3% of the genetic variation, in a region containing a cluster of γ-protocadherin genes and SLC25A2. Other QTLs explaining between 0.5% and 1% of the genetic variation were found on BTA12 and 25. In the PEBS model, a large QTL on BTA7 was synonymous with the QTL for PAI, with minor QTLs located on BTA5, 9, 10, 11, 19, and 20. The validation population for pregnancy status at the end of the breeding season were Angus–Brahman crossbred heifers bred by natural mating. In concordance with the discovery population, the large QTL on BTA7 and QTLs on BTA10 and 12 were *** In summary, QTLs and candidate SNPs identified were associated with pregnancy outcomes in beef heifers, including a large QTL associated with a group of protocadherin genes. Confirmation of these associations

关键词： Beef cattle fertility GWAS QTL

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地球演化历史中氧逸度变化对壳幔循环启动、风化和超大陆循环的指示（英文）

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Science Bulletin 2024年第1期 97-102页

作者：王瑞邬绍宸 Roberto f.Weinberg William J.Collins peter A.Cawood State Key Laboratory of Geological Processes and Mineral Resources Institute of Earth Sciences China University of Geosciences frontiers Science Center for Deep-time Digital Earth China University of Geosciences (Beijing) School of Earth Atmosphere and Environment Monash University The Institute for Geoscience Research Curtin University

We apply a zircon redox index to a global compilation of detrital zircons to track the variation of oxidation state, expressed as ΔfMQ, through Earth’s history. Those from I-type rocks, which comprise mantle and crustal igneous protoliths, including tonalite–trondhjemite–granodiorites(TTGs), generally have a high oxidation state(ΔfMQ > 0). In contrast, zircons from igneous rocks derived from supracrustal source rocks(S-type) are commonly reduced(ΔfMQ function derived from the Gaussian-Kernel-Density-Estimation, we use the maximum likelihood estimation(MLE) to distinguish Stype from I-type zircons through Earth’s history using zircon redox. Voluminous S-type magma production shows a ca. 600 Ma cyclicity that is closely related to the supercontinent cycle. We link a cyclic drop in redox values after 2.6 Ga to periodic S-type magma generation associated with burial and melting of metasedimentary rocks during supercontinent assembly and amalgamation. The ΔfMQ of the detrital zircons rise at ～3.5 Ga followed by a consistent average ΔfMQ > 0 over the last 3 Ga. Given that the redox state of magmas is independent of crustal thickness and silica variation, and elevated values are likely more closely related to tectonic setting, we suggest that the consistent average ΔfMQ > 0 from ca.3.5 Ga onwards relates to recycling of oceanic lithosphere back into the mantle in what eventually became established as subduction zones. The more reduced magmas associated with sedimentary sources, became established at 2.6 Ga, presumably in response to continental rocks rising above sealevel, and follow peaks of productivity associated with the supercontinent cycle.

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Volcanic Risk Perception and Coping Strategies from Mounts Cameroon and Nyiragongo Eruptions, Central Africa: A Comparative Analysis

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Journal of Geoscience and Environment Protection 2024年第6期12卷 161-189页

作者： Mabel N. Wantim Innocent Bradriyo Asong f. Zisuh Louis M. Balgawa Mero Yannah Katcho Karume Nde-fon peter Bih Amban Nchini L. Wayih Emmanuel V. Yenshu Samuel N. Ayonghe Unit of Disaster Risk Management Department of Environmental Science University of Buea Buea Cameroon Observatoire Volcanologique de Goma (OVG) Goma Democratic Republic of the Congo Institute of Geological and Mining Research (IRGM) Yaounde Cameroon faculty of Health Sciences University of Buea Buea Cameroon faculty of Social and Management Sciences University of Buea Buea Cameroon

Approximately 2,000,000 people are exposed to volcanic risks in communities situated at the flanks of Mounts Cameroon (MC) and Nyiragongo (MN) volcanoes in Central Africa. This study therefore sought to investigate risk perception from four previous eruptions of MC, namely the 1959, 1982, 1999, and 2000 eruptions;and two previous eruptions of MN: 1977 and 2002. The study was initiated with co-design workshops held with major stakeholders in the cities of Buea and Goma at the flanks of MC and MN, respectively, in 2017, to develop the research objectives for the study. A non-random questionnaire survey was later conducted within 14 and 15 communities in Buea and Goma respectively, on the effects, perceived risks, and coping strategies for the chosen eruptions. Three age groups (18 - 30, 31 - 45 and >45 years) and gender (male and female) were considered. The population at the flanks of both volcanoes cited scientific and indigenous factors to be responsible for eruptions from these volcanoes. At MC and MN, ≥45% of the sampled participants (with a higher female population) perceived that the sampled eruptions posed a very high risk to the population. In terms of the effects, the age group of 18 - 30 was the least knowledgeable. In terms of direct effect on persons, over 90% of participants at MC and MN attested that they were overcome by fear/panic. On measures to cope with any likely eruption, the following order was established at the flanks of both volcanoes: sensitization of population, use of religious (prayers) and of traditional/indigenous strategies. In terms of future coping strategies, while the males at MC maintained sensitization as the favourite option, 62% of the males at MN opted for traditional/indigenous strategies. The female population at both MC and MN showed a higher preference for religious strategies like prayers.

关键词： Risk Perception Mount Cameroon Mount Nyiragongo Indigenous Buea Goma

Optimizing laser coupling,matter heating,and particle acceleration from solids using multiplexed ultraintense lasers

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Matter and Radiation at Extremes 2024年第4期9卷 16-28页

作者： Weipeng Yao Motoaki Nakatsutsumi Sébastien Buffechoux Patrizio Antici Marco Borghesi Andrea Ciardi Sophia N.Chen Emmanuel d’Humières Laurent Gremillet Robert Heathcote Vojtech Horny Paul McKenna Mark N.Quinn Lorenzo Romagnani Ryan Royle Gianluca Sarri Yasuhiko Sentoku Hans-peter Schlenvoigt Toma Toncian Olivier Tresca Laura Vassura Oswald Willi Julien fuchs LULI-CNRS CEASorbonne UniversitéEcole PolytechniqueInstitut Polytechnique de ParisF-91128 Palaiseau CedexFrance Sorbonne Université Observatoire de ParisUniversité PSLCNRSLERMAF-75005 ParisFrance INRS-EMT 1650 BoulLionel-BouletVarennesQuebec J3X 1S2Canada Center for Plasma Physics School of Mathematics and PhysicsQueen’s University BelfastBelfast BT71NNUnited Kingdom “Horia Hulubei”National Institute for Physics and Nuclear Engineering 30 Reactorului StreetRO-077125 Bucharest-MagureleRomania University of Bordeaux Centre Lasers Intenses et ApplicationsCNRSCEAUMR 5107F-33405 TalenceFrance CEA DAMDIFF-91297 ArpajonFrance Université Paris-Saclay CEALMCE91680 Bruyères-le-ChatelFrance Central Laser facility STFC Rutherford Appleton LaboratoryDidcotUnited Kingdom SUPA Department of PhysicsUniversity of StrathclydeGlasgow G40NGUnited Kingdom Department of Physics University of NevadaRenoNevada 89557USA Institute of Laser Engineering Osaka University2-6 YamadaokaSuitaOsaka 565-0871Japan Institut fur Laser und Plasmaphysik Heinrich Heine Universitat DusseldorfDusseldorfGermany

Realizing the full potential of ultrahigh-intensity lasers for particle and radiation generation will require multi-beam arrangements due to technology ***,we investigate how to optimize their coupling with solid ***,we show that overlapping two intense lasers in a mirror-like configuration onto a solid with a large preplasma can greatly improve the generation of hot electrons at the target front and ion acceleration at the target *** underlying mechanisms are analyzed through multidimensional particle-in-cell simulations,revealing that the self-induced magnetic fields driven by the two laser beams at the target front are susceptible to reconnection,which is one possible mechanism to boost electron *** addition,the resistive magnetic field generated during the transport of the hot electrons in the target bulk tends to improve their *** simulations also indicate that such effects can be further enhanced by overlapping more than two laser beams.

关键词： laser acceleration particle

Phase field modeling with large driving forces

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npj Computational Materials 2023年第1期9卷 623-631页

作者： Jin Zhang Alexander f.Chadwick David L.Chopp peter W.Voorhees Department of Materials Science and Engineering Northwestern UniversityEvanstonIL 60208USA Department of Engineering Sciences and Applied Mathematics Northwestern UniversityEvanstonIL 60208USA

There is growing interest in applying phase field methods as quantitative tools in materials discovery and ***,large driving forces,common in many materials systems,lead to unstable phase field profiles,thus requiring fine spatial and temporal *** demands more computational resources,limits the ability to simulate systems with a suitable size,and deteriorates the capability of quantitative ***,we develop a strategy to map the driving force to a constant perpendicular to the *** with the third-order interpolation function,we find a stable phase field profile that is independent of the magnitude of the driving *** power of this approach is illustrated using three *** demonstrate that by using the driving force extension method,it is possible to employ a grid size orders of magnitude larger than traditional *** approach is general and should apply to many other phase field models.

关键词： forces interpolation apply

DIESL fuels a DGAT-independent triglyceride synthesis pathway

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Life Metabolism 2023年第6期2卷 3-5页

作者： Lauren f.Uchiyama peter Tontonoz Department of Pathology and Laboratory Medicine Molecular Biology InstituteDavid Geffen School of MedicineUniversity of CaliforniaLos AngelesCA 90095United States

Alternative triglyceride(TG)synthesis pathways have yet to be identified in mammalian *** a recent article published in Nature,Brummelkamp and colleagues reported that the acyltransferase transmembrane protein 68(TMEM... 详细信息

关键词： synthesis canonical synthesize