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Exponential Attractor for a Nonlinear Boussinesq Equation

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Acta Mathematicae Applicatae Sinica 2006年第3期22卷 443-450页

作者： Ahmed y. Abdallah Departmcnt of Mathematics University of Jordan Amman 11942 Jordan

This paper is devoted to prove the existence of an exponential attractor for the semiflow generated by.a nonlinear Boussinesq equation. We formulate the Boussinesq equation as an abstract equation in the Hilbert space H0^2（0, 1） × L^2（0, 1）. The main step in this research is to show that there exists an absorbing set for the solution semiflow in the Hilbert space H0^3（0, 1） × H0^1（0, 1）.

关键词： Boussinesq equation absorbing set exponential attractor

Decomposition of trifluoromethane in a dielectric barrier discharge non-thermal plasma reactor

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Journal of Environmental Sciences 2012年第7期24卷 1234-1239页

作者： M. Sanjeeva Gandhi y. S. Mok Department of chemical and Biological Engineering Jeju National University

The decomposition of trifluoromethane （cHF3） was carried out using non-thermal plasma generated in a dielectric barrier discharge （DBD） reactor. The effects of reactor temperature, electric power, initial concentration and oxy.en content were examined. The DBD reactor was able to completely.destroy.cHF3 with alumina beads as a packing material. The decomposition efficiency.increased with increasing electric power and reactor temperature. The destruction of cHF3 gradually.increased with the addition of O2 up to 2%, but further increase in the oxy.en content led to a decrease in the decomposition efficiency. The degradation pathway. were explained with the identified by.products. The main by.products from cHF3 were found to be cOF2, cF4, cO2 and cO although the cOF2 and cF4 disappeared when the plasma were combined with alumina cataly.t.

关键词： trifluoromethane plasma alumina dielectric barrier discharge decomposition

An unsupervised learning approach to study.sy.chroneity.of past events in the South china Sea

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Frontiers of Earth Science 2019年第3期13卷 628-640页

作者： Kevin c. Tse Hon-chim chiu Man-y.n Tsang y.liang Li Edmund y. Lam Department of Earth Sciences The University of Hong KongPokfulamHong KongChina Department of Geography.and centre for Geo-computation Studies Hong Kong Baptist UniversityKowloon TongHong KongChina Department of Earth Sciences University of TorontoCanada Department of Electrical and Electronic Engineering The University of Hong KongPokfulamHong KongChina

Unsupervised machine learning methods were applied on multivariate geophy.ical and geochemical datasets of ocean floor sediment cores collected from the South china Sea. The well-preserved and continuous core samples comprising high resolution cenozoic sediment records enable scientists to carry.out paleoenvironment studies in detail. Bay.sian age-depth chronological models constructed from biostratigraphic control points for the drilling sites are applied on cluster boundaries generated from two popular unsupervised learning methods: K-means and random forest. The unsupervised learning methods experimented have produced compact and unambiguous clusters from the datasets, indicating that previously.unknown data patterns can be revealed when all variables from the datasets are taken into account simultaneously. A study.of sy.chroneity.of past events represented by.the cluster boundaries across geographically.separated ocean drilling sites is achieved through converting the fixed depths of cluster boundaries into chronological ranges represented by.Gaussian density.plots which are then compared with known past events in the region. A Gaussian density.peak at around 7.2 Ma has been identified from results of all three sites and it is suggested to coincide with the initiation of the East Asian monsoon. contrary.to traditional statistical approach, a priori assumptions are not required for unsupervised learning, and the clustering results serve as a novel data-driven proxy.for study.ng the complex and dy.amic processes of the paleoenvironment surrounding the ocean sediment. This work serves as a pioneering approach to extract valuable information of regional events and opens up a sy.tematic and objective way.to study.the vast global ocean sediment datasets.

关键词： machine learning ocean sediments unsupervised classification

Seismites of the Late Triassic Lockatong Formation,Pennsy.vania,USA:implications for Newark Basin border fault movement

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Journal of Palaeogeography 2025年第1期14卷 1-14页

作者： Edward L.Simpson Michael c.Wizevich David L.Fillmore Department of Phy.ical Sciences Kutztown University of Pennsylvania Department of Earth and Space Sciences Central Connecticut State University

Numerous soft-sediment deformation structures(SSDS) within thin-bedded, heterolithic lacustrine shoreline deposits of the Upper Triassic Tumble Falls Member, Lockatong Formation of eastern Pennsy.vania, demonstrate liquefaction, fluidization and shearing features processes affecting sediment. This study.employ. thin-section analy.is of SSDS to interpret them as probable seismites from the Triassic-Jurassic Newark Basin. Sedimentary.structures include right-lateral offset of desiccation cracks and ichnofossils, thrust,reverse, and normal faults with mm-scale offsets, horsts and grabens, lateral spreads, and single and complex multiple networks of dikes and sills and associated sedimentary.volcanoes, thin mudflows on a paleosurface linked to sediment dikes, load and flame structures, ball and pillow structures, recumbent folds, and incipient breccias. Dike fill consists of mudstone, angular sedimentary.clasts, sandstone margins with mudstone cores,and plastically.deformed sediment fill. The SSDS indicate that Late Triassic lacustrine shoreline sediments were subjected to forces, probably.compressive with a minimal shear component reflected in the offset of the dikes and ichnofossils, that induced liquefaction followed by.fluidization and vertical movement of *** forces that altered sediment vertical stability. leading to deformation of the sediment included gravitationally.unstable density.gradients, vertical shear stress, and gravitational body.forces. SSDS can be induced by.seismic and aseismic processes. However, this unique combination of forces and resulting sedimentary.structures indicate an origin by.earthquake activity. likely.produced by.the nearby. active Newark Basin border fault sy.tem. The Lockatong Formation SSDS seismites improve our understanding via thin section analy.is of the rheology.and preservation potential of SSDS in lacustrine shoreline deposits, critical for the geologic history.of Newark Basin, as well as the refinement for paleos

关键词： Seismites Triassic Lockatong Formation Lacustrine Soft-sediment deformation structures

Leptotrichia hongkongensis ***.,a novel Leptotrichia species with the oral cavity.as its natural reservoir

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Journal of Zhejiang University.Science B(Biomedicine & Biotechnology. 2010年第6期11卷 391-401页

作者： Patrick c. y. WOO Samson S. y. WONG Jade L. L. TENG Kit-Wah LEUNG Antonio H. y. NGAN Dong-qing ZHAO Herman TSE Susanna K. P. LAU Kwok-y.ng y.EN State Key.Laboratory.of Emerging Infectious Diseases The University of Hong Kong Hong Kong China Research centre of Infection and Immunology The University of Hong Kong Hong Kong China Department of Microbiology The University of Hong Kong Hong Kong China carol y. centre for Infection The University of Hong Kong Hong Kong China

A straight, non-sporulating, Gram-variable bacillus (HKU24T) was recovered from the blood culture of a patient with metastatic breast carcinoma. After repeated subculturing in BAcTEc Plus Anaerobic/F blood culture broth, HKU24T grew on brucella agar as non-hemoly.ic, pinpoint colonies after 96 h of incubation at 37 °c in an anaerobic environment and aerobic environment with 5% cO2. Growth was enhanced with a streak of Staphy.ococcus aureus. HKU24T was non-motile and catalase-negative, but positive for alkaline phosphatase, β-glucosidase, and α-glucosidase. It hy.roly.ed pheny.phosphonate and reduced resazurin. 16S rRNA, groEL, gy.B, recA, and rpoB sequencing showed that HKU24T occupies a distinct phy.ogenetic position among the Leptotrichia species, being most closely.related to Leptotrichia trevisanii. Using HKU24T groEL, gy.B, recA, and rpoB gene-specific primers, fragments of these genes were amplified from one of 20 oral specimens. Based on phenoty.ic and genoty.ic characteristics, we propose a new species, Leptotrichia hongkongensis sp. nov., to describe this bacterium.

关键词： Leptotrichia hongkongensis Bacterium Blood culture Anaerobic bacteria Novel species

Do aphids actively.search for ant partners？

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Insect Science 2015年第2期22卷 283-288页

作者： christophe y. Fischer Mary.e Vanderplanck Georges c. Lognay.claire Detrain Francois J. Verheggen Laboratory.of Analy.ical chemistry University of Liege Gembloux Agro-Bio Tech Gembloux Research Institute of Biosciences Laboratory of Zoology University of Mons Mons Unit of Social Ecology Universit6 Libre de Bruxelles Brussels Department of Functional and Evolutionary.Entomology University of Liege Gembloux Agro-Bio Tech Gembloux Belgium

The aphid-ant mutnalistic relationships are not necessarily.obligate for neither partners but evidence is that such interactions provide them strong advantages in terms of global fitness. While it is largely.assumed that ants actively.search for their mutualistic partners namely.using volatile cues; whether winged aphids （i.e., aphids＇ most mobile form） are able to select ant-frequented areas had not been investigated so far. Ant-frequented sites would indeed offer several advantages for these aphids including a lower predation pressure through ant presence and enhanced chances of establishing mutuaslistic interactions with neighbor ant colonies. In the field, aphid colonies are often observed in higher densities around ant nests, which is probably.linked to a better survival ensured by.ants＇ services. Nevertheless, this could also result from a preferential establishment of winged aphids in ant-frequented areas. We tested this last hy.othesis through different ethological assay. and show that the facultative my.mecophilous black bean aphid, Aphisfabae L., does not orientate its search for a host plant preferentially.toward ant-frequented plants. However, our results suggest that ants reduce the number of winged aphids leaving the newly.colonized plant. Thus, ants involved in facultative my.mecophilous interactions with aphids appear to contribute to structure aphid populations in the field by.ensuring a better establishment and survival of newly.established colonies rather than by.inducing a deliberate plant selection by.aphid partners based on the proximity.of ant colonies.

关键词： ant aphid Aphisfabae Lasius niger mutualism partner research

Supplemental Materials: Realization of Quantum Maxwell's Demon with Solid-State Spins

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chinese Phy.ics Letters 2018年第4期35卷 1-6页

作者： W.-B. Wang X.-y. chang F. Wang P.-y. Hou y.-y. Huang W.-G. Zhang X.-L. Ouy.ng X.-Z. Huang Z.-y. Zhang H.-y. Wang L. He L.-M. Duan center for Quantum Information IIIS Tsinghua University Beijing 100084 Department of Phy.ics University of Michigan Ann Arbor Michigan 48109 USA

We report experimental realization of a quantum version of Maxwell＇s demon using solid state spins where the information acquiring and feedback operations by.the demon are achieved through conditional quantum gates.A unique feature of this implementation is that the demon can start in a quantum superposition state or in an entangled state with an ancilla observer. Through quantum state tomography. we measure the entropy.in the sy.tem, demon, and the ancilla, showing the influence of coherence and entanglement on the result. A quantum implementation of Maxwell＇s demon adds more controllability.to this paradoxical thermal machine and may.find applications in quantum thermody.amics involving microscopic sy.tems.

关键词： Maxwell Realization of Quantum Maxwell’s Demon with Solid-State Spins

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遗传性基因组不稳定性——种系结构变异增加儿童患颅外实体瘤的风险

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科技导报 2025年第03期 12-13页

作者： Jay.e y.Hehir-Kwa Geoff Macinty.e 荷兰乌得勒支Máxima公主儿科肿瘤学中心西班牙国家癌症研究中心(cNIO)

颅外实体瘤（包括神经母细胞瘤、尤文肉瘤和骨肉瘤）是导致儿童发病和死亡的主要恶性肿瘤类型。相比于成人癌症主要由外源性诱变剂或随年龄增长积累的DNA损伤驱动，儿童癌症的发生缺乏长期的突变积累过程。因此，内源性诱变过程可能是...

颅外实体瘤（包括神经母细胞瘤、尤文肉瘤和骨肉瘤）是导致儿童发病和死亡的主要恶性肿瘤类型。相比于成人癌症主要由外源性诱变剂或随年龄增长积累的DNA损伤驱动，儿童癌症的发生缺乏长期的突变积累过程。因此，内源性诱变过程可能是诱发儿童致癌突变的主要原因。然而，目前这些肿瘤的发生机制仍不清楚。Gillani等在《Science》上报道称，罕

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cOMPUTATIONAL SIMULATION OF RIVER SEDIMENTATION AND MORPHOLOGy.—A REVIEW OF THE STATE OF THE ART

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International Journal of Sediment Research 2005年第1期20卷 7-29页

作者： Sam S. y. WANG F.A.P. Barnard Distinguished Prof. National center for computational Hy.roscience and Engineering MS 38677 The University.of Mississippi USA

In this paper, the state-of-the-art computational simulation technologies for river sedimentation and morphology.are comprehensively.reviewed. Emphasis is on computational modelling, which includes mathematical modelling equations and closures, numerical solution methods, verification and validation, model integration, and applications. Several important areas of future research are recommended.

关键词： River sedimentation Morphological processes computational simulation