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Threat recognition and response in an avian brood-parasite host from New Caledonia

Current Zoology 2021年第3期67卷 255-262页

作者： Alfredo Attisaino Kasper Hlebowicz roman Gula Jorn Theuerkauf Museum and Institute of Zoology Polish Academy of SciencesWarsawPoland Conservation Research New Caledonia La FoaNew Caledonia

Nest predation and avian brood parasitism are the main sources of nest failure in many passerine *** predators threaten both brood and parents,whereas brood parasites pose only a danger to eggs or *** fan-tailed gerygone Gerygone flavolateralis from New Caledonia is subjected to high rates of nest predation by the New Caledonian crow Corvus moneduloides(responsible for about 20-40%of predation)and moderate rates of brood parasitism by the shining bronze-cuckoo Chalcites lucidus(parasitizing about 18%of nests),which also depredates nests that are too advanced for parasitism(13%of nests).To test if fan-tailed gerygones are able to discriminate predators from brood parasites,we presented 3 bird models at active gerygone nests:a brood parasite/small nest predator(shining bronze-cuckoo),a large nest predator(crow),and a small non-native bird(common chaffinch Fringilla coelebs),which is unknown to the gerygone,as a *** assessed the response of adult gerygones to the presentation of each model by measuring the minimum approach distance,number of alarm calls,number of attacks,and time to first nest visit after the presentation(latency).Adult gerygones often attacked the cuckoo,approached but never attacked the chaffinch and always avoided the *** was shorter after an attack response and during brooding,but similar among *** did not find any link between the cuckoo model presentation and later ejection of cuckoo *** conclude that adult fan-tailed gerygones discriminate between different models and respond accordingly to the level of threat but do not show awareness of parasitism risk and increase of nestling ejection rates following exposure to the cuckoo model.

关键词： brood parasitism enemy recognition frontline defense mobbing nest defense nest predation

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Study of relationship between motion of mechanisms in gas operated weapon and its shock absorber

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Defence Technology（防务技术） 2024年第3期33卷 42-54页

作者： Jiri Balla roman Vitek Dung Nguyen Van Zbynek Krist Hung Nguyen Van Department of Weapons and Ammunition University of Defence BrnoCzech Republic Department of Weapons Le Quy Don Technical UniversityHanoiViet Nam Department of Design and Special Engineering Alexander Dubcek University of TrencinSlovakia

The article deals with the motion of the breech block carrier and the weapon casing of an automatic weapon mounted on a flexible carriage and the base of the *** works,which did not consider the dynamic properties of the base of the weapon,did not allow to reconcile the calculated and experimental results of the weapon casing displacement when shooting from firing *** the analysis of the motion of individual parts,the methods of mathematical modelling and firing experiments using a high-speed camera were *** show the best accord with experiment when modelling the system with 4 degrees of *** oscillation of the system regarding the movement of the breech block carrier and the weapon casing was investigated under changed conditions of rate of fire,the use of a muzzle brake and different types of shock *** velocities and displacements of the weapon casing and the breech block carrier at different values of the impulse of the gases to the breech block carrier were determined.

关键词： Shock absorber Gas-operated weapon Force-impulse diagram Recoil system Breech block carrier

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Low-frequency laboratory measurements of the elastic properties of solids using a distributed acoustic sensing system

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第9期15卷 2330-2338页

作者： Vassily Mikhaltsevitch Maxim Lebedev roman Pevzner Alexey Yurikov Konstantin Tertyshnikov Curtin University GPO Box U1987PerthWA 6845Australia Centre for Sustainable Energy and Resources Edith Cowan University270 Joondalup DrJoondalupWA 6027Australia

In recent decades,low-frequency(LF)experiments based on the forced-oscillation(FO)method have become common practice in many rock physics laboratories for measuring the elastic and anelastic properties of ***,the use of the electronic displacement sensors in traditional acquisition systems of FO devices such as conventional capacitive transducers or strain gauges seriously limits both the efficiency and productivity of LF measurements,and,due to the limited contact area of the displacement sensors with a sample under test,increases the requirements for sample *** this paper,we present the first results obtained in the development of a new laboratory method elaborated to measure the elastic properties of *** method is a further development of the FO method where traditional data acquisition is replaced by acquisition based on fiber-optic distributed acoustic sensing(DAS)*** new method was tested in a laboratory study using two FO setups designed for measurements under uniaxial and confining *** study was carried out on a sample made from polymethyl methacrylate(PMMA)and an aluminium standard,first under uniaxial pressure at FO frequencies of 1,10,30,60 and 100 Hz,and then under confining pressure at an FO frequency of 1 *** uniaxial and confining pressures were equal to 10 MPa,and the strain in the PMMA sample in all measurements did not exceed 4×10^(-8).The performance of DAS acquisition was compared with the measurements conducted at a strain of 1×10^(-6) using the traditional FO method based on the use of semiconductor strain gauges and the ultrasonic *** results of the DAS measurements are in good agreement with the FO measurements carried out using semiconductor strain gauges and with the literature data.

关键词： Elasticity and anelasticity Acoustic properties Fourier analysis Wave propagation

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Experimental Setup for the Investigation of Reproducibility of Novel Tool Changing Systems in Nanofabrication Machines

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Nanomanufacturing and Metrology 2021年第3期4卷 181-189页

作者： Florian Weigert roman Hebenstreit Roland FuBl Rene Theska Institute for Design and Precision Engineering Precision Engineering GroupTechnische Universitat IlmenauGustav-Kirchhoff-Platz.298693 IlmenauGermany Institute for Process Measurement and Sensor Technology Technische Universitat IlmenauGustav-Kirchhoff-Str.198693 IlmenauGermany

Nanomeasuring machines developed at the Technische Universitat Ilmenau enable three-dimensional measurements and manufacturing processes with the lowest *** to the requirements for these processes,a highly reproducible and long-term stable tool changing system is *** this purpose,kinematically determined couplings are widely *** state-of-the-art investigations on those are not sufficient for the highest demands on the reproducibility required for this application.A theoretical determination of the reproducibility based on analytical or numerical methods is possible,however not in the desired nanometer *** to this,a measurement setup for the determination of the reproducibility in five degrees of freedom with nanometer uncertainty was ***,potential measuring devices are systematically examined and measurement principles were developed out of this.A three-dimensional vector-based uncertainty analysis is performed to prove the feasibility of the measurement principle and provides a basis for further *** a result,a transla-tory measurement uncertainty of 10 nm and a rotatory uncertainty of 11 nrad can be ***,the measurement setup is designed,focusing on the metrological frame and the lift-off *** developed setup exceeds the uncertainties of the measurement setups presented in the state-of-the-art by an order of magnitude,allowing new in-depth investigations of the reproducibility of kinematic couplings.

关键词： Tool changing Kinematic coupling Measurement setup Uncertainty analysis Precision design

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Reconstructing the neutrally-buoyant particle flow near a singular corner

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Acta Mechanica Sinica 2022年第8期38卷 41-48页

作者： Francesco romanò Univ.Lille CNRSONERAArts et Métiers Institute of TechnologyCentrale LilleUMR 9014-LMFL-Laboratoire de Mécanique des Fluides de Lille-Kampéde FérietUniv.LilleCNRSONERAF-59000LilleFrance

The correction of buoyancy effects is tackled for particles moving close to a singular corner in creeping flow conditions.A few density-mismatched particle trajectories are used to reconstruct the dynamics of a neutrally-buoyant particle all over the target *** propose to take advantage of the dissipative dynamics of density-mismatched particles in order to probe the target ***,we retrieve the neutrally-buoyant particle flow all over the domain by reconstructing the phase space of the density-mismatched particulate flow and taking the limit of the particle-to-fluid density ratio tending to *** robustness of such an approach is demonstrated by deliberately ill-conditioning the reconstruction *** fact,we show that our algorithm well performs even when we rely on qualitatively-different density-mismatched orbit topologies or on bundles of close trajectories rather than homogeneously distributed *** applications to microfluidics and improvements of the proposed algorithm are finally discussed.

关键词： Stokesian dynamics Microfluidics Particle/fluid flow

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Geomechanical analysis of the influence of CO2 injection location on fault stability

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Journal of Rock Mechanics and Geotechnical Engineering 2016年第6期8卷 805-818页

作者： Victor Vilarrasa roman Makhnenko Sohrab Gheibi école Polytechnique Fédérale de Lausanne LausanneSwitzerland Institute of Environmental Assessment and Water Research(IDAEA-CSIC) BarcelonaSpain Associated Unit:Hydrogeology Group(UPC-CSIC) BarcelonaSpain Department of Civil&Environmental Engineering University of Illinois at Urbana-ChampaignUSA Norwegian University of Science and Technology TrondheimNorway

Large amounts of carbon dioxide(CO2) should be injected in deep saline formations to mitigate climate change,implying geomechanical challenges that require further *** build-up induced by CO2injection will decrease the effective stresses and may affect fault *** effects of overpressure induced by CO2injection either in the hanging wall or in the foot wall on fault stability are ***2injection in the presence of a low-permeable fault induces pressurization of the storage formation between the injection well and the *** low permeability of the fault hinders fluid flow across it and leads to smaller overpressure on the other side of the *** variability in the fluid pressure distribution gives rise to differential total stress changes around the fault that reduce its *** a significant pressure build-up induced by the fault,caprock stability around the injection well is not compromised and thus,CO2leakage across the caprock is unlikely to *** decrease in fault stability is similar regardless of the side of the fault where CO2is *** results show that fault core permeability has a significant effect on fault stability,becoming less affected for high-permeable *** appropriate pressure management will allow storing large quantities of CO2without inducing fault reactivation.

关键词： Carbon dioxide(CO_2) injection Geomechanics Fault stability Induced seismicity Fault permeability

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Influence of parameters on the microstructure of a duplex stainless steel joint welded by a GMAW welding process

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Progress in Natural Science:Materials International 2022年第4期32卷 415-423页

作者： Sandra Chacón-Fernández Antonio Portolés García Gerardo romaní Labanda Universidad Politécnica de Madrid Escuela Técnica Superior de Ingenieros Industriales UPM

Duplex stainless steels（DSSs） are widely used in industry for their desirable properties. Any fusion welding technique modifies the microstructure and, consequently, the properties of the material. This paper presents a parametric study of the variables that determine the energy contribution（current, voltage and welding speed） and the structural modifications produced during gas metal arc welding. The analysis comprises metallographic study,phase balance, dimensioning of the weld beads and tensile and hardness tests. The influence of the variables studied on the thermal cycles obtained（temperatures reached and cooling rate） was determined by using a finite element model. The results showed that, in addition to the indicated parameters, the parameter power transfer per volume（W/m3） and the geometry in the bead must be controlled due to their influence on the heat flow distribution and phase balance.

关键词： Welding Heat input GMAW Duplex stainless steels (DSS) Finite element model (FEM)

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What can a heavy U(1)B-L Z'boson do to the muon(g-2)u anomaly and to a new Higgs boson mass?

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Chinese Physics C 2021年第1期45卷 32-46页

作者： Antonio P.Morais roman Pasechnik J.Pedro Rodrigues Departamenlo de Fisica da Universidade de Aveiro and CIDMA Campus de Santiago 3810-183 AveiroPortugal Department of Astronomy and Theoretical Physics Lund UniversitySE 223-62 LundSweden Nuclear Physics Institute ASCR 25068 RezCzech Republic Departamento de Fisica CFMUniversidade Federal de Santa CatarinaC.P.476CEP 88.040-900FlorianopolisSCBrazil

The minimal U(1)B_L extension of the Standard Model(B-L-SM)offers an explanation for neutrino mass generatio n via a seesaw mechanism;it also offers two new physics states,namely an extra Higgs bos on and a new Z'gauge *** emerge nee of a second Higgs particle as well as a new Z'gauge boson,both lin ked to the breaking of a local U(1)B_L symmetry,makes the B-L-SM rather constrained by direct searches in Large Hadron Collider(LHC)*** investigate the phenomenological status of the B-L-SM by confr on ting the new physics predictions with the LHC and electroweak precision *** into account the current bounds from direct LHC searches,we demonstrate that the prediction for the muon(g-2)u anomaly in the B-L-SM yields at most a contribution of approximately 8.9×10^-12,which represents a tension of 3.28 standard deviations,with the current 1σuncertainty,by means of a Z'boson if its mass is in the range of 6.3 to 6.5 TeV,within the reach of future LHC *** means that the B-L-SM,with heavy yet allowed Z‘bos on mass range,in practice,does not resolve the tension between the observed anomaly in the muon(g-2)u and the theoretical prediction in the Standard *** a heavy Z'boson also implies that the minimal value for the new Higgs mass is of the order of 400 GeV.

关键词： beyond Standard Model Higgs physics gauge extensions of the Standard Model Z'boson

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Clinical infections in neurosurgical oncology:An overview

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World Journal of Clinical Cases 2023年第15期11卷 3418-3433页

作者： Tomaz Velnar Nina Kocivnik roman Bosnjak Department of Neurosurgery University Medical Centre LjubljanaLjubljana 1000Slovenia Alma Mater Europaea-ECM Maribor Maribor 2000Slovenia Faculty of Pharmacy University of LjubljanaLjubljana 1000Slovenia

Central nervous system(CNS)infections are urgent conditions with high morbidity and ***,viruses,parasites or fungi can cause *** infections after craniotomies are an important complication of treatment,especially in oncological patients that are already immunologically compromised due to the disease and *** consequence of CNS infections in oncological patients includes longer treatment with antibiotics,additional surgical procedures,higher treatment costs and poorer treatment ***,the management of primary pathology may be prolonged or postponed as a result of the active *** introducing new and improved protocols,tightening controls on their implementation,constantly educating the entire team involved in patient treatment and educating both patients and relatives,the incidence of infections can be reduced effectively.

关键词： Infection Central nervous system Neurosurgery Oncology

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Endoscopic third ventriculostomy in obstructive hydrocephalus: A case report and analysis of operative technique

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World Journal of Clinical Cases 2020年第14期8卷 3039-3049页

作者： Matic Munda Peter Spazzapan roman Bosnjak Tomaz Velnar Department of Neurosurgery University Medical Centre LjubljanaLjubljana 1000Slovenia AMEU-ECM Maribor Ljubljana 1000Slovenia

BACKGROUND The endoscopic third ventriculostomy(ETV)is a neuroendoscopical procedure that represents a more suitable alternative to the extracranial *** consists of fenestrating the floor of the third ventricle and thus establishing a free flow of the cerebrospinal fluid from the ventricles to the site of resorption in the subarachnoid *** offers a more physiological solution and a chance at a shunt-free life for children with *** main indication for the procedure is obstructive hydrocephalus,however,it can also be useful in patients with other forms of *** SUMMARY We present a treatment flow of a 9-year-old patient,diagnosed with an obstructive hydrocephalus due to tectal glioma that was successfully treated with an *** review the important factors influencing the success rate such as age,aetiology,shunt history,preoperative planning and visualisation of the basilar *** Even though the ETV effectively controls obstructive hydrocephalus in more than 75%of all cases,the overall success rate of the procedure varies and could be approved by the correct preoperative patient selection.

关键词： Endoscopic third ventriculostomy Neuroendoscopy Hydrocephalus Case report

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