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Evaluation of sampling strategies to estimate crown biomass

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Forest Ecosystems 2015年第1期2卷 20-30页

作者： Krishna P Poudel Hailemariam Temesgen andrew N gray Department of Forest Engineering Resources and Management College of Forestry Oregon State University USDA Forest Service PNW Research Station3200 SW Jefferson WayCorvallis OR 97331 USA

Background：Depending on tree and site characteristics crown biomass accounts for a significant portion of the total aboveground biomass in the *** biomass estimation is useful for different purposes including evaluating the economic feasibility of crown utilization for energy production or forest products,fuel load assessments and fire management strategies,and wildfire ***,crown biomass is difficult to predict because of the variability within and among species and *** the allometric equations used for predicting crown biomass should be based on data collected with precise and unbiased sampling *** this study,we evaluate the performance different sampling strategies to estimate crown biomass and to evaluate the effect of sample size in estimating crown ***：Using data collected from 20 destructively sampled trees,we evaluated 11 different sampling strategies using six evaluation statistics：bias,relative bias,root mean square error（RMSE）,relative RMSE,amount of biomass sampled,and relative biomass *** also evaluated the performance of the selected sampling strategies when different numbers of branches（3,6,9,and 12）are selected from each *** specific log linear model with branch diameter and branch length as covariates was used to obtain individual branch ***：Compared to all other methods stratified sampling with probability proportional to size estimation technique produced better results when three or six branches per tree were ***,the systematic sampling with ratio estimation technique was the best when at least nine branches per tree were *** the stratified sampling strategy,selecting unequal number of branches per stratum produced approximately similar results to simple random sampling,but it further decreased RMSE when information on branch diameter is used in the design and estimation ***：Use of auxiliary information in design or estimation phase reduc

关键词： Aboveground biomass Crown Sampling strategies Pacific Northwest

Estimating upper stem diameters and volume of Douglas-fir and Western hemlock trees in the Pacific northwest

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Forest Ecosystems 2018年第3期5卷 199-210页

作者： Krishna P.Poudel Hailemariam Temesgen andrew N.gray Department of Forest Engineering Resources and Management College of Forestry Oregon State University USDA Forest Service PNW Research Station

Background: Volume and taper equations are essential for obtaining estimates of total and merchantable stem volume. Taper functions provide advantages to merchantable volume equations because they estimate diameter inside or outside bark at specific heights on the stem, enabling the estimation of total and merchantable stem volume, volume of individual logs, and a height at a given ***: Using data collected from 1218 trees(1093 Douglas-fir(Pseudotsuga menziesii(Mirbel) Franco) and 125 western hemlock(Tsuga heterophylla)), we evaluated the performance of one simple polynomial function and four variable-exponent taper functions in predicting upper stem diameter. Sample trees were collected from different parts of the states of Oregon, Washington, and California. We compared inside-bark volume estimates obtained from the selected taper equation with estimates obtained from a simple logarithmic volume equation for the data obtained in this study and the equations used by the Forest Inventory and Analysis program in the Pacific Northwest(FIA-PNW) in the state of California and western half of the states of Oregon and ***: Variable exponent taper equations were generally better than the simple polynomial taper *** FIA-PNW volume equations performed fairly well but volume equations with fewer parameters fitted in this study provided comparable results. The RMSE obtained from taper-based volume estimates were also comparable with the RMSE of the FIA-PNW volume equations for Douglas-fir and western hemlock trees ***: The taper equations fitted in this study provide added benefit to the users over the FIA-PNW volume equations by enabling the users to predict diameter at any height, height to a given diameter, and merchantable volume in addition to cubic volume including top and stump(CVTS) of Douglas-fir and western hemlock trees in the Pacific Northwest. The findings of this study also give more confidence to the use

关键词： Pacific northwest Biomass equations Utilization standards Diameter inside bark

New radio observations of the Moon at L band

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Research in Astronomy and Astrophysics 2012年第9期12卷 1297-1312页

作者： Xi-Zhen Zhang andrew gray Yan Su Jun-Duo Li Tom Landecker Hong-Bo Zhang Chun-Lai Li National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China zxz @ nao. cas. cn Dominion Radio Astrophysical Observatory Penticton BC V2A 6K3 Canada

We present results of new radio observations of the Moon at L band with the synthesis telescope of the Dominion Radio Astrophysical Observatory Synthesis Telescope. The resolution and temperature sensitivity of the observations are 159 × 87 and 1.7K, respectively. The main results are: (1) the lunar brightness temperature averaged over the whole disk is about 233K while the average brightness temperature for the four quadrants are 228.1K (NE), 239.7K (NW), 233.9K (SW) and 228.8K (SE). The observations reveal large temperature and spatial variations on the Moon for the first time. The highest brightness temperature is about 257 K and it is located along the lunar equator, to the west. The total uncertainty is about 5% due to the absolute accuracy of the fluxes of the primary calibrators; (2) the total degree of po- larization is about 6%. Both polarization intensity and degree of polarization increase from the disk’s center to the limb, and the distribution of the degree of polarization along the limb is not uniform; (3) the new data are used to study the properties of regolith, such as dielectric constant and thickness distribution. The results show that the lunar regolith’s thickness increases from the NW (mare area) to the SE (highland area) regions on the lunar surface.

关键词： techniques: high angular resolution-imaging processing — radio contin- uum: Moon

OnabotulinumtoxinA Nerve Blocks in the Treatment of Occipital Neuralgia

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Pain Studies and Treatment 2016年第3期4卷 29-34页

作者： andrew Ea Terence gray University of New England College of Osteopathic Medicine Biddeford ME USA Mercy Hospital Interventional Pain Center Portland ME USA

Occipital neuralgia is characterized by severe pain, accompanied by tenderness and trigger points, in the distribution of the greater, lesser, and/or third occipital nerves. Occipital neuralgia is typically idiopathic, but also is characterized as a common form of posttraumatic headache. Typical treatments include nerve blocks with local anesthetic, nerve stimulation, pulsed radiofrequency, and cryoablation. OnabotulinumtoxinA (ONA) has recently been utilized in nerve blocks to treat occipital neuralgia, with the potential for a longer duration of pain relief than local anesthetic. Our study retrospectively examined 63 patients treated for occipital neuralgia, including 19 with ONA. 80 - 155 units of ONA were administered bilaterally in the surrounding musculature. A total of 61 patients, including 17 of those subsequently treated with ONA, were treated with local anesthetic, using a 1:1 mixture of 0.25% bupivacaine and 1% lidocaine, plus triamcinolone. Patients reported VAS pain scores before and after their procedures, and again during 4-week follow-up visits. Information on opioid use, overall pain relief, and duration of full relief was also recorded upon follow-up. Patients treated with ONA exhibited significant decreases in average VAS pain scores from 4.1 ± 2.6 pre-procedure to 2.1 ± 2.4 post-procedure (p = 2 × 10 -5), and 3.0 ± 2.5 4 weeks later (p = 0.0234). Mean overall relief was 75.8% ± 25.0%. Treatment with local anesthetic suggested equally efficacious reduction of VAS scores;however, treatment with ONA showed a significantly higher percentage of overall pain relief leading to follow-up. Opioid use did not exhibit significant change, regardless of treatment type. Our results support the hypothesis that use of Onabotulinum-toxinA in occipital nerve blocks leads to significant decreases in pain, while possibly exhibiting a longer duration of action than that of local anesthetic.

关键词： Occipital Neuralgia OnabotulinumtoxinA Botox Bupivacaine Lidocaine

Disability management and rehabilitation for persons with multiple sclerosis

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Neural Regeneration Research 2010年第4期5卷 301-309页

作者： Fary Khan Orla gray Department of Medicine University of MelbourneParkville Department of Rehabilitation Medicine Royal Melbourne HospitalParkville

Multiple sclerosis is the commonest cause of chronic neurological disability in young adults. Patients typically have a normal life span, though with accrued time multiple disabilities with a significant impact on quality of life. This article presents the current literature on symptomatic treatment and rehabilitation for persons with multiple sclerosis. A comprehensive multidisciplinary approach addresses the acute, intermediate and long-term medical, psychological and social issues faced by these individuals. Prevention of medical complications, maintenance and restoration of functional independence, addressing psychosocial factors and issues relating to quality of life are integral to the rehabilitation processes.

关键词： multiple sclerosis disability management rehabilitation multidisciplinary effectiveness literature review neurodegenerative disease neural regeneration

The effect of gas phase polydimethylsiloxane surface treatment of metallic aluminum particles： Surface characterization and flow behavior

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Particuology 2017年第1期15卷 92-101页

作者： Bellamarie Ludwia Jennifer L. gray Applied Research Laboratory The Pennsylvania State University North Atherton Street State College PA 16801 USA Materials Research Institute The Pennsylvania State University USA

Aluminum particles were exposed to gaseous polydimethylsiloxane （PDMS） to produce a hydropho- bic surface coating for enhanced flow and fluidity. Surface retention of the intact PDMS was confirmed through infrared and X-ray photoelectron spectroscopy. Transmission electron microscopy was used to image cross-sections of the treated particles and energy dispersive spectroscopy element maps demon- strated the presence of a surface layer consisting of silicon and oxygen. Density measurements provided evidence for improvements in the Hausner ratio and Carr index of the PDMS-treated aluminum, indicating a reduction in inter-particulate cohesion through increased bulk density. Stability, compressibility, shear, aeration, and permeability of the particles were assessed by powder rheometer. The compressibility was reduced by approximately 32% following surface treatment, revealing a reduction in void space, while Mohr＇s circle analysis and shear testing determined that the extrapolated cohesion value was reduced by approximately 53% and the flow factor at 6 kPa was doubled. Aeration testing showed that the air velocity required to obtain a fluidized bed was on the order of 0.35 mm/s for the treated powder, whereas the raw powder could not be uniformly fluidized. PDMS may be a viable option for the large-scale treatment of aluminum powder for flow applications.

关键词： Aluminum powder Polydimethylsiloxane X-ray photoelectron spectroscopy Diffuse reflectance infrared Fourier transform spectroscopy Flowability FT4 powder rheometer

OnabotulinumtoxinA in the Treatment of Occipital Neuralgia Following Gunshot Injury

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Pain Studies and Treatment 2016年第4期4卷 43-47页

作者： andrew Ea Terence gray University of New England College of Osteopathic Medicine Biddeford USA Mercy Hospital Interventional Pain Center Portland USA

Occipital neuralgia, while typically idiopathic in presentation, is a common form of posttraumatic headache. It is associated with severe pain in the greater, lesser, and/or third occipital nerves, and often accompanied by tenderness or trigger points in the surrounding musculature. OnabotulinumtoxinA (ONA) has been recently utilized in nerve blocks to treat occipital neuralgia, but current literature supporting such use is scarce. We describe a case of occipital neuralgia in a patient following C1 fracture and vertebral artery dissection due to gunshot injury. Successful treatment with bilateral ONA nerve blocks led to an 80% - 90% improvement in pain, with decreased Visual Analog Scale (VAS) pain scores immediately following treatment and upon follow-up 1 month later.

关键词： Occipital Neuralgia OnabotulinumtoxinA Botox Bupivacaine Lidocaine Gunshot

Aphids and their transmitted potato viruses: A continuous challenges in potato crops

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Journal of Integrative Agriculture 2020年第2期19卷 367-375页

作者： XU Yi Stewart M.gray Department of Plant Pathology Nanjing Agricultural UniversityNanjing 210095P.R.China Section of Plant Pathology and Plant-Microbe Biology School of Integrated Plant ScienceCornell UniversityIthacaNY 14850USA Emerging Pest and Pathogens Research Unit United States Department of Agriculture–Agricultural Research ServiceIthacaNY 14850USA

Aphid is one of the most destructive insect pests on cultivated plants in temperate *** piercing-sucking mouthparts and phloem feeding behavior directly damage crops and deplete plant ***(Solanum tuberosum L.)is one of the most important food sources on the planet,and several aphid species,e.g.,Myzus persicae(Sulzer)(green peach aphid)and Macrosiphum euphorbiae(Thomas)(potato aphid)(Hemiptera:Aphididae)colonize potato and transmit several economically important ***-transmitted potato viruses have been emerging all over the world as a very serious problem in potato production,inducing a wide variety of foliar and tuber symptoms,leading to severe yield reduction and loss of tuber *** this review,recent advances in understanding the interactions of potato viruses with their hosts,aphid vectors and the environment are described.

关键词： aphids virus potato vector transmission

Evolution of Microalloyed Linepipe Steels With Particular Emphasis on the “Near Stoichiometry” Low Carbon,0.10 Percent Niobium “HTP” Concept

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Journal of Iron and Steel Research International 2011年第S1期18卷 652-657页

作者： gray J.Malcolm Microalloyed Steel Institute Inc. 5100 Westheimer Ste 540HoustonTX 77056 USA

Microalloyed linepipe steels were first introduced in 1959 at strength levels around 52-60 ksi [1] [2].The steels were generally strengthened by niobium or vanadium used *** strengths levels increased to X-70 in the early 1970’s niobium and vanadium were used in combination and controlled rolling was introduced on a broad *** strengths decrease tolerance for impurities and non-metallic inclusions which required improved steelmaking ***,carbon,and nitrogen were reduced and continuous casting was increasingly applied which required improved ladle refining and deoxidation ***-molybdenum steels were introduced by IPSCO in 1972 [3] and by Italsider in 1974 [4].Steels with higher niobium contents were also introduced in the early 1970’s but available steelmaking technologies limited the use of optimum niobium to carbon ratios,*** approaching *** the steels benefited from the effect of niobium in retarding austenite recrystallization at relatively high rolling temperatures and they developed attractive combinations of strength and toughness in old manufacturing facilities using simple (relaxed) rolling *** in the price of molybdenum and vanadium in the past decade and expanded application of API Grade X-80 linepipe,have led to more widespread use of niobium contents up to 0.11 percent,in combination with 0.02-0.03 percent carbon (near stoichiometry) thus maximizing the effects of solute niobium during rolling,in lowering transformation temperature,and thereby reducing reliance on other alloying,often expensive,*** history of these developments will be presented and applications of the concept will be summarized.

关键词： HTP Low Carbon,0.10 Percent Niobium Near Stoichiometry Evolution of Microalloyed Linepipe Steels With Particular Emphasis on the Concept