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Waveform liDAR concepts and applications for potential vegetation phenology monitoring and modeling:a comprehensive review

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Geo-Spatial Information Science 2021年第2期24卷 179-200,I0001页

作者： eric Ariel l Salas Agricultural Research Development Program(ARDP) Central State UniversityWilberforceUSA

Researchers continually demonstrated through published literature how liDAR could create unparalleled measurements of ecosystem structure and forest *** are a number of studies conducted utilizing waveform liDAR products for terrestrial monitoring,but those that deal specifically with the assessment of space-borne waveform liDAR for monitoring and modeling of phenology is very *** review highlights the waveform liDAR system and looks into satellite sensors that could link waveform liDAR and vegetation phenology,such as the proposed NASA’s Global Ecosystem Dynamics Investigation(GEDI)and the Japanese Experimental Module(JEM)-borne liDAR sensor named MOlI(Multi-footprint Observation lIDAR and Imager).Further,this work examines the richness and utility of the waveform returns and proposes a spline-function-derived model that could be exploited for estimating the leaf-shooting *** new approach may be utilized for ecosystem-level phenological studies.

关键词： Ecosystems gedi moli phenology vegetation modeling waveform liDAR

An ensemble method for gene discovery based on DNA microarray data

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Science China(life Sciences) 2004年第5期47卷 396-405页

作者： Kathy l. MOSER eric J. TOPOl Department of Medicine Institute of Human Genetics University of Minnesota Minnesota 55455 USA Center for Cardiovascular Genetics Department of Cardiovascular Medicine the Cleveland Clinic Foundation 9500 Euclid Avenue Cleveland Ohio 44195 USADepartment of Molecular Cardiology the Cleveland Clinic Foundation 9500 Euclid Avenue Cleveland Ohio 44195 USA

The advent of DNA microarray technology has offered the promise of casting new insights onto deciphering secrets of life by monitoring activities of thousands of genes simulta-neously. Current analyses of microarray data focus on precise classification of biological types, for example, tumor versus normal tissues. A further scientific challenging task is to extract dis-ease-relevant genes from the bewildering amounts of raw data, which is one of the most critical themes in the post-genomic era, but it is generally ignored due to lack of an efficient approach. In this paper, we present a novel ensemble method for gene extraction that can be tailored to fulfill multiple biological tasks including (i) precise classification of biological types; (ii) disease gene mining; and (iii) target-driven gene networking. We also give a numerical application for (i) and (ii) using a public microarrary data set and set aside a separate paper to address (iii).

关键词： microarrays,ensemble decision,recursive partition tree,feature gene selection.

A new approach to solar flare prediction

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Frontiers of physics 2020年第3期15卷 123-149,F0004页

作者： Michael l.Goodman Chiman Kwan Bulent Ayhan eric l.Shang Jacobs Space Exploration Group Natural Environments Branch-EV44NASA Marshall Space Flight CenterHuntsvilleAL35812USA Applied Research llC 9605 Medical Center Drive-Suite 127 ERockvilleMD20850USA

All three components of the current density are required to compute the heating rate due to free magnetic energy *** we present a first test of a new model developed to determine if the times of increases in the resistive heating rate in active region(AR)photospheres are correlated with the subsequent occurrence of M and X flares in the corona.A data driven,3D,non-force-free magnetohydrodynamic model restricted to the near-photospheric region is used to compute time series of the complete current density and the resistive heating rate per unit volume[Q(t)]in each pixel in neutral line regions(NlRs)of 14 *** model is driven by time series of the magnetic field B measured by the Helioseismic&Magnetic Imager on the Solar Dynamics Observatory(SDO)*** Doppler periods due to SDO orbital motion are filtered out of the time series for B in every AR *** each AR,the cumulative distribution function(CDF)of the values of the NlR area integral Qi(t)of Q(t)is found to be a scale invariant power law distribution essentially identical to the observed CDF for the total energy released in coronal *** suggests that coronal flares and the photospheric Qi are correlated,and powered by the same *** model predicts spikes in Qi with values orders of magnitude above background *** spikes are driven by spikes in the non-force free component of the current *** times of these spikes are plausibly correlated with times of subsequent M or X flares a few hours to a few days *** spikes occur on granulation scales,and may be signatures of heating in horizontal current *** is also found that the times of relatively large values of the rate of change of the NlR unsigned magnetic flux are also plausibly correlated with the times of subsequent M and X flares,and spikes in Qi.

关键词： active regions magnetic fields flares forecasting heating photosphere models magnetohydrodynamics

Perioperative management of the patient with rheumatoid arthritis

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World Journal of Orthopedics 2014年第3期5卷 283-291页

作者： Megan l Krause eric l Matteson Division of Rheumatology Department of MedicineMayo ClinicRochesterMN 55905United States

A multidisciplinary approach is required to care for patients with rheumatoid arthritis(RA)in the perioperative *** preparation for surgery,patients must have a cardiovascular risk assessment performed due to the high risk of heart disease in patients with *** of RA is with immunomodulatory medications,which present unique challenges for the perioperative ***,there is no consensus on how to manage disease modifying antirheumatic drug(DMARD)therapy in the perioperative *** of the data to guide therapy is based on retrospective cohort *** regarding DMARDs require an individualized approach with collaboration between surgeons and *** regarding biologic therapy is to hold the therapy in the perioperative period with the length of time dictated by the half-life of the *** attention is required at the time of surgery for potential need for stress dose ***,there must be close communication with anesthesiologists in terms of airway management particularly in light of the risk for cervical spine *** are no consensus guidelines regarding the requirement for cervical spine radiographs prior to ***,history and exam alone cannot be relied upon toidentify cervical spine *** with RA who undergo joint replacement arthroplasty are at higher risk for infection and dislocation compared to patients with osteoarthritis,necessitating particular vigilance in postoperative follow *** review summarizes available evidence regarding perioperative management of patients with RA.

关键词： Rheumatoid arthritis Perioperative management Disease modifying antirheumatic drugs Tumor necrosis factor inhibitors Postsurgical complications

Reduced combustion time model for methane in gas turbine flow fields

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Journal of Natural Gas Chemistry 2009年第2期18卷 145-155页

作者： Mouna lamnaouer Robert C. Ryder Andreja Brankovic eric l. Petersen Graduate Research Assistant Mechanical Materials & Aerospace Engineering University of Central FloridaOrlando Fl 32816 USA President Engineering Flow ParametricsIvoryton CT USA Vice President Flow ParametricsIvoryton CT USA Associate Professor Department of Mechanical Engineering Texas A&M University College StationTX 77843 USA

Computational fluid dynamics （CFD） modeling of the complex processes that occur within the burner of a gas turbine engine has become a critical step in the design process. However, due to computer limitations, it is very difficult to completely couple the fluid mechanics solver with the full combustion chemistry. Therefore, simplified chemistry models are required, and the topic of this research was to provide reduced chemistry models for CH4/O2 gas turbine flow fields to be integrated into CFD codes for the simulation of flow fields of natural gas-fueled burners. The reduction procedure for the CH4/O2 model utilized a response modeling technique wherein the full mechanism was solved over a range of temperatures, pressures, and mixture ratios to establish the response of a particular variable, namely the chemical reaction time. The conditions covered were between 1000 and 2500 K for temperature, 0.1 and 2 for equivalence ratio in air, and 0.1 and 50 atm for pressure. The kinetic time models in the form of ignition time correlations are given in Arrhenius-type formulas as functions of equivalence ratio, temperature, and pressure; or fuel-to-air ratio, temperature, and pressure. A single ignition time model was obtained for the entire range of conditions, and separate models for the low-temperature and high-temperature regions as well as for fuel-lean and rich cases were also derived. Predictions using the reduced model were verified using results from the full mechanism and empirical correlations from experiments. The models are intended for （but not limited to） use in CFD codes for flow field simulations of gas turbine combustors in which initial conditions and degree of mixedness of the fuel and air are key factors in achieving stable and robust combustion processes and acceptable emission levels. The chemical time model was utilized successfully in CFD simulations of a generic gas turbine combustor with four different cases with various levels of fuel-air premixin

关键词： CH4 ignition time correlations reduced kinetic model

Stem cell treatments for oropharyngeal dysphagia:Rationale,benefits,and challenges

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World Journal of Stem Cells 2020年第9期12卷 1001-1012页

作者： eric K Tran Kevin O Juarez Jennifer l long David Geffen School of Medicine University of California-Los AngelesLos AngelesCA 90095United States Department of Otolaryngology Yale School of MedicineNew HavenCT 06511United States Department of Head and Neck Surgery David Geffen School of MedicineUniversity of California-Los AngelesLos AngelesCA 90095United States Greater los Angeles VA Healthcare System Los AngelesCA 90073United States

Dysphagia,defined as difficulty swallowing,is a common symptom negatively impacting millions of adults *** prevalence ranges from 14 to 33 percent in those over age 65 to over 70 percent in a nursing home *** elderly,those with neurodegenerative diseases,head and neck cancer patients,and those with autoimmune conditions such as Sjögren's syndrome are disproportionately *** dysphagia refers specifically to difficulty in initiating a swallow due to dysfunction at or above the upper esophageal sphincter,and represents a large proportion of dysphagia *** treatments are limited and are often *** cell therapy is a new and novel advancement that may fill a much-needed role in our treatment ***,we review the current literature regarding stem cell treatments for oropharyngeal *** discussed include tissue regeneration advancements as a whole and translation of these principles into research surrounding tongue dysfunction,xerostomia,cricopharyngeal dysfunction,and finally an overview of the challenges and future directions for *** this field of study remains in its early stages,initial promising results show potential for the use of stem cell-based therapies to treat oropharyngeal dysphagia and warrant further research.

关键词： Dysphagia Xerostomia Hemiglossectomy Stem cells Myoblasts Mesenchymal stem cells

Would behavioral thermoregulation enable pregnant viviparous tropical lizards to cope with a warmer world?

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Integrative Zoology 2017年第5期12卷 379-395页

作者： Saúl lÓPEZ-AlCAIDE Miguel NAKAMURA eric N.SMITH Enrique MARTÍNEZ-MEYER Departament of Zoology Institute of BiologyNational Autonomous University of MexicoMexico CityMexico Center for Research in Mathematics GuanajuatoMexico Amphibian and Reptile Diversity Research Center and Department of Biology University of Texas at ArlingtonArlingtonTexasUSA

Sceloporus lizards depend on external heat to achieve their preferred temperature(Tsel)for performing physiological *** both in the field and laboratory indicates that pregnant females of this Genus select body temperatures(Tb)lower than 34℃ as higher temperatures may be lethal to ***,thermoregulation is crucial for successful embryo *** the increase in global air temperature,it is expected that the first compensatory response of species that inhabit tropical climates will be behavioral *** tested whether viviparous Sceloporus formosus group lizards in the wild exhibited differences in thermoregulatory behavior to achieve the known Tsel for developing embryos regardless of local thermal *** quantified field active body temperature,thermoregulatory behavior mechanisms(time of sighting,microhabitat used and basking time)and available microhabitat thermal conditions(*** temperature)for 10 lizard species during gestation,distributed along an altitudinal *** applied both conventional and phylogenic analyses to explore whether Tb or behavioral thermoregulation could be regulated in response to different thermal *** species showed no significant differences in field Tb during gestation regardless of local thermal *** contrast,they exhibited significant differences in their behavioral thermoregulation associated with local environmental *** on these observations,the differences in thermoregulatory behavior identified are interpreted as compensatory adjustments to local thermal *** conclude that these species may deal with higher temperatures predicted for the tropics by modulating their thermoregulatory behavior.

关键词： altitudinal gradient behavior global warming Sceloporus formosus thermal stress

Momentum considerations inside near-zero index materials

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light(Science & Applications) 2022年第8期11卷 1782-1789页

作者： Michaël lobet Iñigo liberal larissa Vertchenko Andrei Vlavrinenko Nader Engheta eric Mazur John A.Paulson School of Engineering and Applied Sciences Harvard University9 Oxford StreetCambridgeMA02138USA Department of Physics and Namur Institute of Structured Materials University of NamurRue de Bruxelles 515000NamurBelgium Electrical and Electronic Engineering Department Universidad Pública de NavarraCampus ArrosadíaPamplona31006Spain Department of Photonics Engineering Technical University of DenmarkØrsteds Plads 345ADK-2800 KgsLyngbyDenmark Department of Electrical and Systems Engineering University of PennsylvaniaPhiladelphiaPA19104USA

Near-zero index (NZI) materials, i.e., materials having a phase refractive index close to zero, are known to enhance or inhibit light-matter interactions. Most theoretical derivations of fundamental radiative processes rely on energetic considerations and detailed balance equations, but not on momentum considerations. Because momentum exchange should also be incorporated into theoretical models, we investigate momentum inside the three categories of NZI materials, i.e., inside epsilon-and-mu-near-zero (EMNZ), epsilon-near-zero (ENZ) and mu-near-zero (MNZ) materials. In the context of Abraham–Minkowski debate in dispersive materials, we show that Minkowski-canonical momentum of light is zero inside all categories of NZI materials while Abraham-kinetic momentum of light is zero in ENZ and MNZ materials but nonzero inside EMNZ materials. We theoretically demonstrate that momentum recoil, transfer momentum from the field to the atom and Doppler shift are inhibited in NZI materials. Fundamental radiative processes inhibition is also explained due to those momentum considerations inside three-dimensional NZI materials. Absence of diffraction pattern in slits experiments is seen as a consequence of zero Minkowski momentum. lastly, consequence on Heisenberg inequality, microscopy applications and on the canonical momentum as generator of translations are discussed. Those findings are appealing for a better understanding of fundamental light-matter interactions at the nanoscale as well as for lasing applications.

关键词： materials. momentum Minkowski

Quantifying foliar trait variation and covariation in sun and shade leaves using leaf spectroscopy in eastern North America

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Forest Ecosystems 2024年第5期11卷 728-742页

作者： Zhihui Wang Philip A.Townsend eric l.Kruger Anna K.Schweiger Guangdong Provincial Key laboratory of Remote Sensing and Geographical Information System Guangdong Open Laboratory of Geospatial Information Technology and ApplicationGuangzhou Institute of GeographyGuangdong Academy of SciencesGuangzhou510070China Department of Forest and Wildlife Ecology University of Wisconsin-Madison1630 Linden DriveMadisonWI53706USA Department of land Resources and Environmental Sciences Montana State University334 Leon Johnson HallBozemanMT59717USA

Characterizing foliar trait variation in sun and shade leaves can provide insights into inter-and intra-species resource use strategies and plant response to environmental ***,datasets with records of multiple foliar traits from the same individual and including shade leaves are sparse,which limits our ability to investigate trait-trait,trait-environment relationships and trait coordination in both sun and shade *** presented a comprehensive dataset of 15 foliar traits from sun and shade leaves sampled with leaf spectroscopy,including 424 individuals of 110 plant species from 19 sites across eastern North *** investigated trait variation,covariation,scaling relationships with leaf mass,and the effects of environment,canopy position,and taxonomy on trait ***,sun leaves had higher leaf mass per area,nonstructural carbohydrates and total phenolics,lower mass-based chlorophyll a+b,carotenoids,phosphorus,and potassium,but exhibited species-specific *** between sun and shade leaf traits,and trait-environment relationships were overall consistent across *** main dimensions of foliar trait variation in seed plants were revealed including leaf economics traits,photosynthetic pigments,defense,and structural *** and canopy position collectively explained most of the foliar trait *** study highlights the importance of including intra-individual and intra-specific trait variation to improve our understanding of ecosystem *** findings have implications for efficient field sampling,and trait mapping with remote sensing.

关键词： Foliar traits leaf trait variation Trait-environment covariation Shade leaves NEON leaf spectroscopy