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An evaluation of visual and measurement-based methods for estimating deposited fine sediment

International Journal of Sediment Research 2016年第4期31卷 368-375页

作者： Elizabeth Conroy Jonathan n.Turner anna Rymszewicz Michael Bruen John J.O'Sullivan Mary Kelly-Quinn School of Biology and Environmental Science University College Dublin School of Geography Planning and Environmental PolicyUniversity College Dublin UCD Dooge Centre for Water Resources Research School of CivilStructural and Environmental EngineeringUCD Earth InstituteUniversity College Dublin

A wide range of methods are commonly used to measure deposited fine sediment and quantify substrate quality in rivers as part of bioassessment or monitoring *** this laboratory-based experiment known amounts of three sediment types(sand,topsoil,peat) were added to mesocosms and four methods of measuring deposited fine sediment;turbidity,estimation of released sediment,Turner-Hillis deposited sediment sampler(DSS) and visual estimation of%surface cover were *** objective of the study was to evaluate which of these methods for estimating deposited sediment best discriminates between levels of deposited fine sediment added and assesses the effects of inter-observer variability between%surface cover *** turbidity measurement and the resuspension method were strongly related to levels of added sediment,it proved difficult using the two methods to resolve differences between adjacent levels of added sediment e.g.50 g and 100 *** cover estimations were also strongly related to added sediment levels and were better able to distinguish between adjacent levels of added ***,we found no significant differences between the%surface cover estimations between *** from this laboratory experiment strongly endorse the use of visual estimation of surface cover in field *** work evaluating the turbidity and resuspension methods under field conditions would also be beneficial.

关键词： Deposited fine sediment Sediment sampling Turbidity Re-suspension Visual estimation

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nonlinear Backstepping Ship Course Controller

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International Journal of Automation and computing 2009年第3期6卷 277-284页

作者： anna Witkowska Roman Smierzchalski Gdansk University of Technology Faculty of Electrical Engineering and Automatic Narutowicza 11/12

A ship, as an object of course control, is characterized by a nonlinear function describing the static maneuvering characteristics. The backstepping method is one of the methods that can be used during the designing process of a nonlinear course controller for ships. The method has been used for the purpose of designing two configurations of nonlinear controllers, which were then used to control the ship course. One of the configurations took dynamic characteristic of a steering gear into account during the designing stage. The parameters of the obtained nonlinear control structures have been tuned to optimise the operation of the control system. The optimisation process has been performed by means of genetic algorithms. The quality of operation of the designed control algorithms has been checked in simulation tests performed on the mathematical model of a tanker. The results of simulation experiments have been compared with the performance of the system containing a conventional proportional-derivative （PD） controller.

关键词： Backstepping method genetic algorithm marine ships control nonlinear control tuning parameters.

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Potential role of lava lizards as pollinators across the Galápagos Islands

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Integrative Zoology 2020年第2期15卷 144-148页

作者： Sandra HERVÍAS-PAREJO Manuel nOGALES Beatriz GUZMÁn María del Mar TRIGO Jens MOLESEn Pablo VARGAS Ruben HELEnO anna TRAVESET Global Change Research Group Mediterranean Institute for Advanced StudiesMallorcaBalearic IslandsSpain Island Ecology and Evolution Research Group Institute of Natural Products and AgrobiologyCanary IslandsSpain Royal Botanical Garden of Madrid MadridSpain Department of Plant Biology Málaga UniversityMálagaSpain Department of Bioscience Aarhus UniversityAarhusDenmark Centre for Functional Ecology Department of Life SciencesUniversity of CoimbraCoimbraPortugal

Lizards have been reported as important pollinators on several oceanic *** we evaluate the potential role of Galápagos lava lizards(Microlophus spp.)as pollinators across their *** 3 years,we sampled pollen transport by 9 lava lizard species on the 10 islands where they are present,including 7 single-island ***,only 25 of 296 individuals sampled(8.4%)transported pollen of 10 plant species,the most common being Prosopis juliflora,Exodeconus miersii,Sesuvium *** Cordia *** least 8 of these plant species were native,and none were confirmed as introduced to the *** the low overall proportion of individuals carrying pollen,this was observed in 7 of the nine lizard species,and on 8 of the ten main islands(Española,Fernandina,Floreana,Isabela,Marchena,Pinta,Santa Cruz and Santiago),suggesting that this is a widespread *** results reported here support the potential role of lava lizards as pollinators across their radiation,although they may represent a relatively modest contribution when compared with birds and ***,we cannot discard that lizards may be ecologically significant for particular plant species and ecosystems given the specific climatic condition and functional diversity of each island.

关键词： flower visitation Microlophus spp. mutualistic interactions pollination vertebrate radiation

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Molecular Mechanisms of Ethylene-Auxin Interaction

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Molecular Plant 2013年第6期6卷 1734-1737页

作者： Linda Robles anna Stepanova Jose Alonso Department of Plant and Microbial Biology North Carolina State University Raleigh NC 27695 USA

During the century-long history of plant hormone research, the focus in this area has shifted from the original physi- ological experiments to molecular, genetic, biochemical, and, more recently, genomic approaches. During this jour- ney, we have learned about the many effects these natural compounds have on plant growth and development at the morphological and molecular levels. We have also uncov- ered how these molecules are sensed by the plant cell and how they trigger signaling cascades that relay information to the nucleus, ultimately culminating in a transcriptional cas- cade. With this fundamental knowledge at hand, the main efforts in the field have turned towards a more integrative systems approach, in which the function of a hormone is considered in the context of the complex and dynamic net of interactions with other hormones or, more broadly, with other developmental and environmental signals. Initially, due to the complexity of the problem, most crosstalk studies have focused on pairwise interactions between two or few hormones. Special attention has been given to the interac- tions between ethylene and auxin, perhaps in part because of the experimental tractability of some of the processes in which the interaction between these two hormones is most manifested. An excellent review has been recently written describing the many different processes in which these two hormones are known to interact, either synergistically, such as root growth inhibition, or antagonistically, as is the case for lateral root formation （Muday et al., 2012）. Rather than following this process-centered approach, herein we decided to focus on the molecular mechanisms involved in the inter- action between ethylene and auxin. We take a closer look at the best-known transcriptional and posttranscriptional points of interaction, as well as revisit the most recent experimental findings that suggested additional levels of ethylene-auxin crosstalk.

关键词： Ethylene Auxin Interaction

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Happy together？ Avoidance of conspecifics by gregarious mussels

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Current Zoology 2018年第1期64卷 53-61页

作者： anna DZIERZYnSKA-BIALOnCZYK Aleksandra SKRZYPCZAK Jaroslaw KOBAK Faculty of Biology and Environmental Protection Department of Invertebrate Zoology Nicolaus CopernicusUniversity Lwowska 1 Torun 87-100 Poland

Zebra mussel Dreissena polymorpha is a Ponto-Caspian species invasive in Europe and north America, with great environmental impact. It lives byssally attached to hard substrata in large aggregations, which is often explained by its preferences for conspecifics, though direct evidence for such preferences has been rather limited so far. We studied the reactions of zebra mussels to con- specifics, hypothesizing that they may either be attracted to one another or form aggregations only in the absence of alternative attachment sites, in Experiment 1, we tested mussel tendency to detach from existing druses depending on druse size （2-25 individuals） and substratum type （soft： sand; hard： glass）. Mussels detached significantly more often on the hard substratum and from larger druses compared to soft substratum and smaller druses, respectively. This indicates that mussels tended to avoid conspecifics at high density, particularly when alternative substratum was available. In Experiment 2, we tested the responses of single mussels to distant （3 or 15cm） conspecifics （0, 3, 15 individuals per 2.51 tank） on the sandy substratum. The presence of conspecifics, regardless of their distance and density, resulted in single unattached mussels staying more often in their initial positions. Mussels did not move preferentially towards or away from the conspecifics. Thus, even on unsuitable substratum mussels were not attracted by conspecifics and probably exhibited an avoidance reaction by reducing their movement. This suggests that dense mussel aggregations are formed due to the lack of available alternative attachment sites rather than due to their preferences for conspecifics.

关键词： active detachment Dreissena polymorpha movement mussel aggregations zebra mussel.

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Scalable nanocomposite parylene-based memristors:Multifilamentary resistive switching and neuromorphic applications

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nano Research 2023年第2期16卷 3207-3214页

作者： anna n.Matsukatova Artem Yu.Vdovichenko Timofey D.Patsaev Pavel A.Forsh Pavel K.Kashkarov Vyacheslav A.Demin Andrey V.Emelyanov national Research Centre“Kurchatov Institute” Moscow 123182Russia Physics Department Lomonosov Moscow State UniversityMoscow 119991Russia Moscow Institute of Physics and Technology DolgoprudnyjMoscow oblast 141701Russia Enikolopov Institute of Synthetic Polymeric Materials Russian Academy of SciencesMoscow 117993Russia Physics Department Saint Petersburg State UniversitySt.Petersburg 199034Russia

Memristors are promising candidates for synapse emulation in brain-inspired neuromorphic computing *** main obstacle to their usage in such systems is high variability of memristive characteristics and its severe negative effect on the neural network *** paper addresses the issue from two points of view on the example of the parylene-based memristors:(i)the methods of the memristor internal stochasticity decrease and(ii)the methods of the memristive neural network architecture *** introduction of an optimal Ag nanoparticle concentration(3 vol.%–6 vol.%)to the memristive structure leads to a statistically significant decrease in the switching voltage variation and endurance ***,it is shown that post-fabrication annealing improves memristive characteristics,e.g.,resistive switching window increases by an order of magnitude and exceeds 106,the switching voltage variation decreases by a factor of 2(down to 7%for the set and 17%for the reset voltage),and thermostability is *** transmission electron microscopy and impedance spectroscopy analysis allowed establishing a multifilamentary resistive switching mechanism for nanocomposite parylene-based *** simulation of the formal neural network based on these memristors demonstrates high classification accuracy with low variation for an important biomedical task,heart disease prediction,after careful feature selection and network architecture *** prospects of the controlled incorporation of the nanocomposite parylene-based memristors in neural networks are brightened by their scaling possibility in crossbar geometry.

关键词： memristor resistive switching neuromorphic computing parylene nanocomposite

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Antagonizing amyloid-β/calcium-sensing receptor signaling in human astrocytes and neurons: a key to halt Alzheimer's disease progression?

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neural Regeneration Research 2015年第2期10卷 213-218页

作者： Ilaria Dal Prà anna Chiarini Ubaldo Armato Histology & Embryology Section Department of Life & Reproduction Sciences University of Verona Medical School

Astrocytes＇ roles in late-onset Alzheimer＇s disease （LOAD） promotion are important, since they survive soluble or fibrillar amyloid-β peptides （Aβs） neurotoxic effects, undergo alterations of intracellular and intercellular Ca2＋ signaling and gliotransmitters release via the Aβ/a7-nAChR （αT-nicotinic acetylcholine receptor） signaling, and overproduce/oversecrete newly synthesized Aβ42 oligomers, nO, and VEGF-A via the Aβ/CaSR （calcium-sensing receptor） signaling. Recently, it was suggested that the nMDAR （n-methyl-D-aspartate receptor） inhibitor nitromemantine would block the synapse-destroying effects of Aβ/α7-nAChR signaling. Yet, this and the progressive extracellular accrual and spreading of Aβ42 oligomers would be stopped well upstream by nPS 2143, an allosteric CaSR antagonist （calcilytic）.

关键词： Alzheimer's disease amyloid-β astrocytes Ca2+ calcilytic calcium-sensing receptor nitromemantine nPS 2143 aT-nicotinic acetylcholine receptor

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Risk modeling of femoral neck fracture based on geometric parameters of the proximal epiphysis

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World Journal of Orthopedics 2022年第8期13卷 733-743页

作者： anna D Shitova Olga n Kovaleva anna V Olsufieva Inchekhanum A Gadzhimuradova Dmitry D Zubkov Mikhail O Kniazev Tatyana S Zharikova Yury O Zharikov International School“Medicine of the Future” I.M.Sechenov First Moscow State Medical University(Sechenov University)Moscow 119991MoscowRussia Department of Human Anatomy I.M.Sechenov First Moscow State Medical University(Sechenov University)Moscow 125009MoscowRussia Department of Biomedical Disciplines of the Faculty of Medicine Nonstate Educational Private Institution of Higher Education"Moscow Financial and Industrial University“Synergy”Moscow 125190MoscowRussia Institute of Clinical Medicine I.M.Sechenov First Moscow State Medical University(Sechenov University)Moscow 119991MoscowRussia

BACKGROUnD Fractures of the proximal femur epiphysis are problematic for state health care because they are associated with severe medical and social problems and high morbidity and mortality *** To model the potential risk of hip fracture via femur geometric *** Seventy educational cadaveric femurs from people aged 14 to 80 years,10 X-ray images from the records of the Human Anatomy Department and 10 X-ray images from the Department of Traumatology,Orthopedics and Disaster Surgery of Sechenov University,were *** parameters of the fractured bone were measured using images captured with a Canon d60 *** projection values of the proximal epiphysis of the cadaveric femurs and geometric parameters of the bones shown in the X-ray images were measured with Autodesk software(AutoCAD 2018).Analysis of the video frames showing bone rotation reveal that the greater trochanter can be inscribed in a parallelepiped,where one of the faces is parallel to the plane of view in the frontal standard projection and is *** angle of bone rotation obtained by turning the cube corresponded to the angle measured with the second *** reliable method of calculating the rotation of the bone relative to the anterior projection was employed in subsequent *** geometric parameters of the femur were measured using X-ray images according to the proposed *** The geometric parameters of 70 femurs were analyzed,and correlation coefficients were *** measurement results were compared with those reported by other *** potential influence of femur geometry on force distribution in the proximal epiphysis of the femur was described,and a 2-dimensional model of the femur epiphysis associated with minimal neck fracture risk was *** assessment of the geometric parameters of the femoral epiphysis indicated the greatest risk of a varus fracture of the neck if the angle of the minimal resistance zone(AMRZ)

关键词： Fracture Proximal epiphysis of femur Risk Traumatology Hip neck Risk assessment scale

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Do Larger and Older Individuals Occupy Better Areas in the Colony of Qinghai Toad-headed Agamas?

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亚洲两栖爬行动物研究:英文版 2023年第3期14卷 183-190页

作者： Eduard GALOYAn natalia SOPILKO anna KOVALYEVA Yin QI A.n.Severtsov Institute of Ecology and Evolution Moscow 119071Russia Lomonosov Moscow State University Leninskie Gori 1Moscow 119991Russia Chengdu Institute of Biology Chinese Academy of SciencesChengdu 610041SichuanChina

Group living reduces the chances of *** is also true for burrowing animals,which use burrows as refuges to escape *** in the center of a colony is the safest because it offers access to the greatest number of burrows;however,it is stressful due to frequent aggressive interactions *** predicted that larger and older animals should occupy areas of a colony with a higher density of burrows than smaller and younger *** test this prediction,we observed individually marked Qinghai toad-headed agamas(Phynocephalus vlangalii)from a single colony late in the breeding season when females were *** of burrows was the highest and distance between them the shortest in the center of the *** encounters were more frequent in the central part of the colony than on its *** found a negative correlation between body size and distance to the center of the colony for females,but not for *** was no such correlation between age of individuals and distance to the center of the *** in this species likely compete with other females and males for central burrows in the colony even after mating season *** suggest that gravid females likely compete for the dense burrows within the central part of the colony mainly due to their relatively lower sprint speed and higher probability of being caught by a predator if they are not refuged in a burrow.

关键词： burrow distribution competition group living lizards Phrynocephalus space use

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In-vehicle VOCs composition of unconditioned,newly produced cars

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Journal of Environmental Sciences 2014年第5期26卷 1052-1061页

作者： Krzysztof Brodzik Joanna Faber Damian Lomankiewicz anna Golda-Kopek BOSMAL Automotive Research and Development Institute Ltd

The in-vehicle volatile organic compounds （VOCs） concentrations gains the attention of both car producers and users. In the present study, an attempt was made to determine if analysis of air samples collected from an unconditioned car cabin can be used as a quality control measure. The VOCs composition of in-vehicle air was analyzed by means of active sampling on Carbograph 1TD and Tenax TA sorbents, followed by thermal desorption and simultaneous analysis on flame ionization and mass detector （TD-GC/FID-MS）. nine newly produced cars of the same brand and model were chosen for this study. Within these, four of the vehicles were equipped with identical interior materials and five others differed in terms of upholstery and the presence of a sunroof; one car was convertible. The sampling event took place outside of the car assembly plant and the cars tested left the assembly line no later than 24 hr before the sampling took place. More than 250 compounds were present in the samples collected; the identification of more than 160 was confirmed by comparative mass spectra analysis and 80 were confirmed by both comparison with single/multiple compounds standards and mass spectra analysis. In general, aliphatic hydrocarbons represented more than 60% of the total VOCs （TVOC） determined. Depending on the vehicle, the concentration of aromatic hydrocarbons varied from 12% to 27% of total VOCs. The very short period between car production and sampling of the in-vehicle air permits the assumption that the entire TVOC originates from off-gassing of interior materials. The results of this study expand the knowledge of in-vehicle pollution by presenting information about car cabin air quality immediately after car production.

关键词： volatile organic compounds (VOCs) car interior materials emission

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