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On the Homology of the Dual de Rham Complex

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Acta Mathematica Sinica,English Series 2022年第10期38卷 1666-1676页

作者： roman mikha.lov Laboratory of Modern Algebra and Applications St.Petersburg State University14th Line29bSaint Petersburg199178Russia St.Petersburg Department of Steklou Mathematical Institute Fontanka 27SaintPetersburg191023Russia

We study the homology of the dual de Rham complex as functors on the category of abelian *** give a description of homology of the dual de Rham complex up to degree 7 for free abelian groups and present a corrected ve... 详细信息

关键词： Dual de Rham complex polynomial functor divided powers derived functors

Genotypic diversity and genotype identity of resident species drive community composition

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Journal of Plant Ecology 2020年第2期13卷 224-232页

作者： Věroslava Hadincová Hana Skálová Zuzana Münzbergová Department of Population Ecology Institute of BotanyAcademy of Sciences of the Czech RepublicCzech Republic Department of Botany Faculty of ScienceCharles UniversityCzech Republic Department of Invasion Ecology Institute of BotanyAcademy of Sciences of the Czech RepublicCzech Republic

Aims Species-rich plant communities are more resistant to *** the past decade it was demonstrated that genetic variation also has many ecological *** our study we aimed to test whether the patterns of response to the genetic diversity of a resident species differ between colonizing species of different growth forms and whether the response is affected by soil *** We established experimental stands of a common grass,Festuca rubra,harbouring three levels of genetic diversity(1,6 or 18 clonal genotypes,referred to as genotypic diversity)under two soil nutrient *** the fourth year after the stands were established,we sowed a mixture of four colonizers into the stands:a stoloniferous legume(Trifolium repens),a broad-leaf tussock grass(Anthoxanthum odoratum),a largerosette forb(Plantago lanceolata)and a small-rosette forb(Campanula rotundifolia).We observed species establishment and growth over 3 *** tested whether colonization success depended on genotypic diversity,specific Festuca genotypes,soil nutrients and colonizer growth *** Findings The colonization success and biomass of the colonizers were significantly affected by the genotypic diversity and the genotype identity of the resident clonal *** response,however,differed between the *** strongest response to the genotypic diversity of the resident species was observed in the tussock grass with a growth form and architecture similar to the resident *** large-rosette species responded in early stages of growth whereas the stoloniferous legume did not respond at *** intraspecific genotypic diversity and genotype identity of the resident species play an important role in the assembly of plant communities.

关键词： clonal grass biodiversity effects colonization

Dynamic Modelling of the DEP Controlled Boiling in a Microchannel

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Journal of Thermal Science 2018年第2期27卷 167-174页

作者： Marcin Lackowski roman Kwidzinski Institute of Fluid Flow Machinery Polish Academy of Sciences

The paper presents theoretical analysis of flow dynamics in a heated microchannel in which flow rate may be controlled by dielectrophoretic(DEP) forces. Proposed model equations were derived in terms of lumped parameters characterising the system comprising of DEP controller and the microchannel. In result, an equation for liquid height of rise in the controller was obtained from momentum balances in the two elements of the considered system. In the model, the boiling process in the heated section of microchannel is taken into account through a pressure drop, which is a function of flow rate and uniform heat flux. Presented calculation results show that the DEP forces influence mainly the flow rate in the microchannel. In this way, by proper modulation of voltage applied to the DEP controller, it is possible to lower the frequency of Ledinegg instabilities.

关键词： dielectrophoresis boiling microchannel two-phase flow pressure drop

Modeling static friction behavior of elastic–plastic spherical adhesive microcontact in full-stick condition

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Friction 2024年第11期12卷 2594-2610页

作者： Guo XIANG roman GOLTSBERG Izhak ETSION Department of Mechanical Engineering TechnionHaifa 32000Israel

The static friction behavior of an elastic–plastic spherical adhesive microcontact between a rigid flat and a deformable sphere under combined normal and tangential loading is studied by the finite element method(FEM).The contact between the sphere and the rigid flat is assumed to be full-stick,and the sliding inception is related to a loss of tangential *** intermolecular force between the rigid flat and the sphere is assessed by the Lennard–Jones(LJ)potential,which is applied to the sphere and the rigid flat by a user *** evolution of the adhesive force with tangential displacement in the full-stick condition is *** results indicate that the increasing effect of adhesive energy on the static friction coefficient gradually diminishes with an increase in the adhesive energy and the external normal ***,based on an extensive parametric study,an empirical dimensionless expression is obtained to predict the static friction coefficient of the spherical adhesive microcontact considering the intermolecular force.

关键词： adhesive spherical microcontact Lennard–Jones(LJ)potential elastic–plastic static friction

An in vitro demonstration of a passive,acoustic metamaterial as a temperature sensor with mK resolution for implantable applications

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Microsystems & Nanoengineering 2024年第1期10卷 41-54页

作者： Lucrezia Maini Vicente Genovés roman Furrer Nikola Cesarovic Christofer Hierold Cosmin roman Micro-and Nanosystems Department of Mechanical and Process EngineeringETH ZurichTannenstrasse 38092 ZurichSwitzerland. Translational Cardiovascular Technology Department of Health Science and TechnologyETH ZurichLeopold-Ruzicka-Weg 48093 ZurichSwitzerland. Transport at Nanoscale Interfaces Swiss Federal Laboratories for Materials Science and TechnologyEMPAÜberlandstrasse 1298600 DübendorfSwitzerland Department of Cardiothoracic and Vascular Surgery Deutsches Herzzentrum der Charite(DHZC)13353 BerlinGermany

Wireless medical sensors typically utilize electromagnetic coupling or ultrasound for energy transfer and sensor *** transfer and management is a complex aspect that often limits the applicability of implantable sensor *** this work,we report a new passive temperature sensing scheme based on an acoustic metamaterial made of silicon embedded in a polydimethylsiloxane *** to other approaches,this concept is implemented without additional electrical components in situ or the need for a customized receiving unit.A standard ultrasonic transducer is used for this demonstration to directly excite and collect the reflected *** metamaterial resonates at a frequency close to a typical medical value(5 MHz)and exhibits a high-quality *** the design features of the metamaterial with the high-temperature sensitivity of the polydimethylsiloxane matrix,we achieve a temperature resolution of 30 *** value is below the current standard resolution required in infrared thermometry for monitoring postoperative complications(0.1 K).We fabricated,simulated,in vitro tested,and compared three acoustic sensor designs in the 29-43℃(~302-316 K)temperature *** this concept,we demonstrate how our passive metamaterial sensor can open the way toward new zero-power smart medical implant concepts based on acoustic interrogation.

关键词： passive resolution utilize

Repellent effects of pongam oil on settlement and oviposition of the common greenhouse whitefly Trialeurodes vaporariorum on chrysanthemum

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Insect Science 2007年第3期14卷 219-224页

作者： roman PAVELA GERHARD HERDA Research Institute of Crop Production Prague Czech University of Agriculture Prague Czech Republic

The repellent activities, including host deterrence and anti-oviposion, of pongam oil against the adults of the common greenhouse whitefly Trialeurodes vaporariorum Westwood in greenhouses were tested. Chrysanthemum plants treated with different concentrations （0.5%-2.0%） of water-suspended pongam oil showed relatively long-lasting host deterrent and anti-oviposition effects on the adults of greenhouse whitefly. Although the repellent effect declined in time and concentration, strong effects on the reduction of oviposition were found, which lasts, dependent on concentration at least 12 days after application.

关键词： botanical insect control agent oviposition pongam oil repellence Trialeurodes vaporariorum

s cascade reinforcement likely when sympatric tnd allopatric populations exchange migrants？

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Current Zoology 2016年第2期62卷 155-167页

作者： roman YUKILEVICH Fumio AOKI Department of Biology Union College Schenectady NY 12308 Department of Ecology and Evolution Stony Brook University Stony Brook NY 11794

When partially reproductively isolated species come back into secondary contact, these taxa may diverge in mating preferences and sexual cues to avoid maladaptive hybridization, a process known as reinforcement. This phenomenon often leads to reproductive character displacement （RCD） between sympatric and allopatric populations of reinforcing species that differ in their exposure to hybridization. Recent discussions have reinvigorated the idea that RCD may give rise to additional speciation between conspecific sympatric and allopatric populations, dubbing the concept ＂cascade reinforcement.＂ Despite some empirical studies supporting cascade reinforcement, we still know very little about the conditions for its evolution. In the present article, we address this question by developing an individual-based population genetic model that explicitly simulates cascade reinforcement when one of the hybridizing species is split into sympatric and allopatric populations. Our results show that when sympatric and allopatric populations reside in the same environment and only differ in their exposure to maladaptive hybridization, migration between them generally inhibits the evolution of cascade by spreading the reinforcement alleles from sympatry into allopatry and erasing RCD. Under these conditions, cascade reinforcement only evolved when migration rate between sympatric and allopatric populations was very low. This indicates that stabilizing sexual selection in allopatry is generally ineffective in preventing the spread of reinforcement alleles. Only when sympatric and allopatric populations experienced divergent ecological selection did cascade reinforcement evolve in the presence of substantial migration. These predictions clarify the conditions for cascade reinforcement and facilitate our understanding of existing cases in nature.

关键词： Dobzhansky-Muller incompatibilities hybrid zones reproductive character displacement reproductive isolation secondary contact sexual isolation speciation

Evaluation of Hypervisor Stability towards Insider Attacks

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Journal of Electronic Science and Technology 2016年第1期14卷 37-42页

作者： roman Kulikov Svetlana Kolesnikova the Department of Computer Systems Design and Security National Research University of Information Technology

Virtualization technology plays a key role in cloud ***,the security issues of virtualization tools（hypervisors,emulators,etc.） should be under precise ***,threats of insider attacks are *** virtualization tools and hypervisors have been poorly protected from this type of ***,hypervisor is one of the most critical elements in cloud computing ***,hypervisor vulnerabilities analysis is ***,a formal model of insider attack on hypervisor is ***,on the basis of the formal attack model,we propose a new methodology of hypervisor stability *** this paper,certain security countermeasures are considered that should be integrated in hypervisor software architecture.

关键词： Cloud computing hypervisor insider attack hypervisor stability virtualization virtual machine

Symptomatic bradycardia in tuberculosis-related giant bullae(vanishing lung syndrome):A case report

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Asian Pacific Journal of Tropical Medicine 2024年第9期17卷 425-428页

作者： Reynard Laysandro Jessie Julian Mila Meha Resley Ongga Mulia mikha Nazamta Yusfiatuzzahra School of Medicine and Health Science Atma Jaya Catholic University of Indonesia JakartaIndonesia Faculty of Medicine and Veterinary Medicine University of Nusa Cendana East Nusa TenggaraIndonesia Faculty of Medicine Trisakti University JakartaIndonesia

Rationale:Vanishing lung syndrome is rare and can be associated with a history of smoking and marijuana *** occurrence of giant bullae can also be linked to infections,particularly tuberculosis in tropical *** concerns:A 26-year-old male complained of weakness,severe vomiting,and reduced breathlessness when lying on the left *** had a history of pulmonary tuberculosis two years ***:Symptomatic bradycardia in tuberculosis-related giant ***:The patient was recommended to undergo an elective bullectomy,but he decided not to proceed with the *** sulfate was administered to alleviate symptoms of bradycardia,while a standardized anti-tuberculosis regimen were started for the next six ***:Following 7 days of intensive care treatment involving antituberculosis medications and atropine sulfate,the patient achieved hemodynamic stability,opting against bullectomy despite residual symptoms of *** six months of antituberculosis therapy notably alleviated symptoms without requiring ***:Increasing intrathoracic pressure can also be caused mechanically by giant *** symptoms in vanishing lung syndrome are reversible and can be alleviated once the underlying cause is *** this case,symptomatic bradycardia was reduced only with tuberculosis treatment without bullectomy intervention。

关键词： Bradycardia Infected giant bullae Tuberculosis Vanishing lung syndrome