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Earthquake Science 2010年第5期23卷 439-447页

作者： Keith D. Koper veronica L. Hawley Department of Geology and Geophysics University of Utah Department of Earth and Atmospheric Sciences Saint Louis University

We present a new approach to polarization analysis of seismic noise recorded by three-component seismometers. It is based on statistical analysis of frequency-dependent particle motion properties determined from a large number of time windows via eigenanalysis of the 3-by-3, Hermitian, spectral covariance matrix. We applied the algorithm to continuous data recorded in 2009 by the seismic station SLM, located in central North America. A rich variety of noise sources was observed. At low frequencies （〈0.05 Hz） we observed a tilt-related signal that showed some elliptical motion in the horizontal plane. In the microseism band of 0.05-0.25 Hz, we observed Rayleigh energy arriving from the northeast, but with three distinct peaks instead of the classic single and double frequency peaks. At intermediate frequencies of 0.5-2.0 Hz, the noise was dominated by non-fundamental-mode Rayleigh energy, most likely P and Lg waves. At the highest frequencies （〉3 Hz）, Rayleigh-type energy was again dominant in the form of Rg waves created by nearby cultural activities. Analysis of the time dependence of noise power shows that a frequency range of at least 0.02-1.0 Hz （much larger than the microseism band） is sensitive to annual, meteorologically induced sources of noise.

关键词： seismic noise polarization analysis central North America

Ni/Al Intermetallics Plasma Transferred Arc Processing

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材料热处理学报 2004年第05B期25卷 948-951页

作者： veronica A. B. Almeida Ana Sofia C. M. D'Oliveira Master student - PIPE Federal University of Parana Curitiba/BrazilMechanical Engineering Department Federal University of Parana Curitiba/Brazil

In-situ alloy development during surface processing allows for a limitless materials selection to protect components exposed to severe service conditions. In fact surface alloying offers the possibility to strengthen surface components with alloys that would not be possible to process otherwise. This work used Plasma transferred arc (PTA) hardfacing for surface alloying. Different amounts of aluminium powder, 5-25%, were added to a Ni based superalloy, from Hastealloy C family, in the atomized form. The mixture was homogeneized in a ball mill and PTA deposited on carbon steel substrate. The influence of different processing parameters on the final surface alloy was evaluated as current intensity and depositing velocity were varied. Coatings were characterized by optical and scanning electronic microscopy, X-ray diffraction and Vickers microhardness profiles, under a 500g load. Results showed that PTA hardfacing is an adequate surface alloying. For the conditions tested increasing hardness was obtained by solid solution for the lower amounts of Al added and due to the new intermetallic phases for the richer Al mixture.

关键词： PTA合金等离子转移电弧 Ni/Al金属互化物表面处理

Aldynoglia cells and modulation of RhoGTPase activity as useful tools for spinal cord injury repair

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Neural Regeneration Research 2016年第7期11卷 1043-1045页

作者： Ernesto Doncel-perez Manuel Nieto-Sampedro Grupo de Quimica Neuro-Regenerativa Hospital Nacional de Paraplejicos Servicio de Salud de Castilla La Mancha (SESCAM) Toledo Spain Grupo de Plasticidad Neural Instituto Cajal CSIC Madrid Spain

A combined approach in spinal cord injury （SCI） therapy is the modulation of the cellular and molecular processes involved in glial scarring. Aldaynoglial cells are neural cell precursors with a high capacity to differentiate into neurons, promote axonal growth, wrapping and myelination of resident neurons. These important characteristics of aldaynoglia can be combined with specific inhibition of the RhoGTPase activity in astroglia and microglia that cause reduction of glial proliferation, retraction of glial cell processes and myelin production by oligodendrocytes. Previously we used experimental central nervous system （CNS） injury models, like spinal cord contusion and striatal lacunar infarction and observed that administration of RhoGTPase glycolipid inhibitor or aldaynoglial cells, respectively, produced a significant gain of functional recovery in treated animals. The combined therapy with neuro-regenerative properties strategy is highly desirable to treat SCI for functional potentiation of neurons and oligodendrocytes, resulting in better locomotor recovery. Here we suggest that treatment of spinal lesions with aldaynoglia from new rospheres plus local administration of a RhoGTPase inhibitor could have an additive effect and promote recovery from SCI.

关键词： glial scar astrocyte microglia neurospheres aldaynoglia axonal growth myelination glycosideinhibitor

What leads to variations in the results of life-cycle energy assessment?An evidence-based framework for residential buildings

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Energy and Built Environment 2021年第4期2卷 392-405页

作者： Hossein Omrany veronica Soebarto Jian Zuo Ehsan Sharifi Ruidong Chang School of Architecture&Built Environment-University of Adelaide AdelaideAustralia

Residential buildings are one of the major contributors to climate change due to their significant impacts on global energy ***,most countries have introduced regulations to minimize energy use in residential *** date,the focus of these regulations has mainly been on operational energy while excluding embodied *** recent years,extensive studies have highlighted the necessity of minimizing both embodied energy and operational energy by applying the life-cycle energy assessment(LCEA)***,the absence of a standardized framework and calculation methodology for the analysis of embodied energy has reportedly led to variations in the LCEA *** research endeavoured to explore the causes of variations,with a limited focus on calculating embodied *** the undertaken attempts,there is still a need to investigate the key parameters causing variations in LCEA results by examining methodological approaches of the current studies toward quantifications of embodied and operational *** paper aims to address three primary questions:‘what is the current trend of methodological approach for applying LCEA in residential buildings?’;‘what are the key parameters causing variations in LCEA results?’;and‘how can the continued variations in the application of LCEA in residential buildings be overcome?’.To this end,40 LCEA studies representing 157 cases of residential buildings across 16 countries have been critically *** findings reveal four principal categories of parameters that potentially contribute to the varying results of LCEAs:system boundary definition,calculation methods,geographical context,and interpretation of *** paper also proposes a conceptual framework to minimize variations in LCEA studies by standardizing the process of conducting LCEAs.

关键词： Life cycle energy assessment Life cycle assessment Residential buildings Energy efficiency Embodied energy Operational energy

Asiatic Callosciurus squirrels as seed dispersers of exotic plants in the Pampas

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Current Zoology 2016年第3期62卷 215-219页

作者： S. Yasmin BOBADILLA veronica V, BENITEZ M. Laura GUICHON Ecologia de Mamiferos Introducidos Departamento de Ciencias Basicas Instituto de Ecologia y Desarrollo Sustentable (INEDES) Universidad Nacional de Lujan Ruta 5 y 7 Lujan (6700) Buenos Aires Argentina

Seed dispersal by exotic mammals exemplifies mutualistic interactions that can modify the habitat by facilitating the establishment of certain species. We examined the potential for endozoochoric dispersal of exotic plants by Callosciurus erythraeus introduced in the Pampas Region of Argentina. We identified and characterized entire and damaged seeds found in squirrel faeces and evaluated the germination capacity and viability of entire seeds in laboratory assays. We collected 120 samples of squirrel faeces that contained 883 pellets in seasonal surveys conducted between July 2011 and June 2012 at 3 study sites within the main invasion focus of C. erythraeus in Argentina. We found 226 entire seeds in 21% of the samples belonging to 4 species of exotic trees and shrubs. Germination in laboratory assays was recorded for Morus alba and Casuarina sp.; however, germination percentage and rate was higher for seeds obtained from the fruits than for seeds obtained from the faeces. The largest size of entire seeds found in the faeces was 4.2 ~ 4.0 ram, whereas the damaged seeds had at least 1 dimension ≥ 4.7 ram. Our results indi- cated that C. erythraeus can disperse viable seeds of at least 2 species of exotic trees. C. erythraeus predated seeds of other naturalized species in the region. The morphometric description suggested a restriction on the maximum size for the passage of entire seeds through the digestive tract of squirrels, which provides useful information to predict its role as a potential disperser or predator of other species in other invaded communities.

关键词： Argentina Callosciurus erythraeus endozoochory invasive species mutualism.

Data-driven modeling of power generation for a coal power plant under cycling

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Energy and AI 2023年第1期11卷 90-105页

作者： Himanshu Sharma Laurentiu Marinovici veronica Adetola Herbert T.Schaef Pacific Northwest National Laboratory RichlandWA 99354USA

Increased penetration of renewables for power generation has negatively impacted the dynamics of conventional fossil fuel-based power *** power plants operating on the base load are forced to cycle,to adjust to the fluctuating power *** results in an inefficient operation of the coal power plants,which leads up to higher operating *** overcome such operational challenge associated with cycling and to develop an optimal process control,this work analyzes a set of models for predicting power ***,the power generation is intrinsically affected by the state of the power plant components,and therefore our model development also incorporates additional power plant process variables while forecasting the power *** present and compare multiple state-of-the-art forecasting data-driven methods for power generation to determine the most adequate and accurate *** also develop an interpretable attention-based transformer model to explain the importance of process variables during training and *** trained deep neural network(DNN)LSTM model has good accuracy in predicting gross power generation under various prediction horizons with/without cycling events and outperforms the other models for long-term *** DNN memory-based models show significant superiority over other state-of-the-art machine learning models for short,medium and long range *** transformer-based model with attention enhances the selection of historical data for multi-horizon forecasting,and also allows to interpret the significance of internal power plant components on the power *** newly gained insights can be used by operation engineers to anticipate and monitor the health of power plant equipment during high cycling periods.

关键词： Deep learning Interpretable temporal fusion transformer Long short-term memory Coal power plant cycling

Occurrence data may provide unreliable thermal preferences and breadth of species

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Current Zoology 2015年第6期61卷 972-982页

作者： Sara VILLEN-perez Luis M. CARRASCAL Department of Biogeography and Global Change National Museum of Natural Sciences MNCN-CSIC. C/José Gutiérrez Abascal 2 28006 Madrid Spain.

Accurate information on the thermal preference and specialization of species is needed to understand and predict spe- cies geographical range size and vulnerability to climate change. Here we estimate the position and breadth of species within thermal gradients based on the shape of the response curve of species abundance to temperature. The objective of the study is to compare the measurements of this approach based on abundance data with those of the classical approach using species＇ occur- rence data. The relationship between species＇ relative abundance and minimum winter temperature of 106 bird species wintering in the Iberian Peninsula is modeled at 100 Km2 resolution with quadratic logistic regressions. From these models we calculated the preferred temperature of species as the temperature at which the abundance is maximized, and the thermal breadth of species as the relative area under the temperature-abundance curve. We also estimated the thermal preferences and breadth of species as the average temperature and temperature range of the UTM cells in which the species are present. The abundance-temperature response curves reveal that birds prefer higher temperatures to overwinter, and are more thermally selective, than is measured by the classical approach. Moreover, response curves detect a higher inter-specific variability in both thermal preferences and ther- mal breadth of species. As occurrence data gives the same weight to cells with one or many individuals, the average temperature of the cells in which the species is present roughly reflects the average temperature in the region of study and not the environ- mental preferences of species .

关键词： Abundance-temperature response curve Birds Species occurrence Thermal breadth Thermal preferences Winter

Misfolded amyloid-βstrains and their potential roles in the clinical and pathological variability of Alzheimer’s disease

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Neural Regeneration Research 2023年第1期18卷 119-120页

作者： Sara Kelley Nelson perez-Urrutia Rodrigo Morales Department of Neurology University of Texas Health Science Center at HoustonHoustonTXUSA Centro Integrativo de Biologia y Quimica Aplicada(CIBQA) Universidad Bernardo O’HigginsSantiagoChile

Potential causes for the clinical and pathological variability observed in Alzheimer’s disease(AD):AD is an age-related neurodegenerative disorder characterized by the impairment of cognitive functions such as memory,learning,and *** commonly described clinical symptoms are due to particular pathological changes in the brain,including inflammation,synaptic loss,and neuronal *** changes are a consequence of the accumulation of abnormally folded amyloid-β(Aβ)and tau proteins in specific areas of the central nervous *** the progressive aging of the world’s population,the number of people affected by AD is expected to substantially and consistently increase in the coming *** positions AD as one of the main public health challenges in the near future.

关键词： clinical Alzheimer amyloid

Woodland Mediterranean birds can resist a dry extreme cold wave

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Current Zoology 2014年第4期60卷 429-437页

作者： Sara VILLEN-perez Luis M. CARRASCAL Department of Biogeography and Global Change Museo Nacional de Ciencias Naturales (CSIC) C/Jos6 Guti6rrez Abascal 228006 Madrid Spain

The ecological consequences of climate extreme events are still poorly understood, especially those related to cold episodes. Winter cold spells might imperil the energy balance of small passerines, thus compromising their survivorship. Here we analyze how the abundance and habitat use of three tree-gleaning passerine species wintering in a montane oakwood of central Spain at ca. 1,300 m a.s.1, was influenced by the cold wave that hit Europe in February 2012. We monitored temperature, wind and the relative abundance of great tit Parus major, blue tit Cyanistes caeruleus and long-tailed tit Aegithalos caudatus in 15 plots throughout three periods： before, during and after the cold wave. Our results clearly rule out widespread mortality and temporal migration of the studied passerine populations, as the abundance of these species did not diminish during the cold wave. Moreover, the species usually foraging higher in the tree canopy -and thus more exposed to windmoved to the less windy woodland plots （long-tailed tit） and reduced their foraging height above ground during the cold wave （long-tailed tit and blue tit）, probably to mitigate the deleterious effects of wind chill. Therefore, these forest birds were able to cope with a dry cold wave that was statistically extreme in terms of temperature and wind chill, according to the historic climate records of the region. It seems that, at least when foraging substrates are not heavily covered by snow or ice, Mediterranean birds can resist an extreme cold wave [Current Zoology 60 （4）： 429-437, 2014].

关键词： Cold wave Harsh weather Mediterranean oakwoods Temperature Tree-gleaning birds Wind chill

Overcoming thermo-optical dynamics in broadband nanophotonic sensing

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Microsystems & Nanoengineering 2021年第4期7卷 47-57页

作者： Mingkang Wang Diego J.perez-Morelo Vladimir Aksyuk Microsystems and Nanotechnology Division National Institute of Standards and TechnologyGaithersburgMD 20899USA Institute for Research in Electronics and Applied Physics University of MarylandCollege ParkMD 20742USA

Advances in integrated photonics open up exciting opportunities for batch-fabricated optical sensors using high-quality-factor nanophotonic cavities to achieve ultrahigh sensitivities and *** sensitivity improves with increasing optical power;however,localized absorption and heating within a micrometer-scale mode volume prominently distorts the cavity resonances and strongly couples the sensor response to thermal dynamics,limiting the sensitivity and hindering the measurement of broadband time-dependent ***,we derive a frequency-dependent photonic sensor transfer function that accounts for thermo-optical dynamics and quantitatively describes the measured broadband optomechanical signal from an integrated photonic atomic force microscopy nanomechanical *** this transfer function,the probe can be operated in the high optical power,strongly thermo-optically nonlinear regime,accurately measuring low-and intermediate-frequency components of a dynamic signal while reaching a sensitivity of 0.7fm/Hz^(1/2) at high frequencies,an improvement of=10x relative to the best performance in the linear ***,we discover that a higher transduction gain and sensitivity are achieved with lower quality-factor optical modes for low signal *** limited to optomechanical transducers,the derived transfer function is generally valid for describing the small-signal dynamic responses of a broad range of technologically important photonic sensors subject to the thermo-optical effect.

关键词： dynamics regime hinder