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Journal of Forestry research 2015年第3期26卷 719-733页

作者： Jennifer G.Klutsch Betsy A.Goodrich william r.jacobi Department of Bioagricultural Sciences and Pest Management Colorado State University Ft. CollinsCO 80523-1177 USA Department of renewable resources University of Alberta 442 Earth Science BuildingEdmonton AB T6G 2E3 Canada School of Forestry Northern Arizona University PO Box 15018 Flagstaff AZ 86011 USA

Whitebark pine （Pinus albicaulis） populations are in decline across the species＇ range due to historic wildfire exclusion, mountain pine beetle （Dendroctonus ponderosae, MPB） outbreaks, and an invasive fungal pathogen causing the disease white pine blister rust （Cronartium ribicola, WPBr）. Despite reliance on stand- replacing fires, information on whitebark pine regeneration occurrence is limited and the trajectory of future forests is largely unknown in some areas of the range. regeneration densities were assessed in burned and adjacent non-burned areas at six high elevation locations in northwest Wyoming where stand-replacing fires occurred 8-32 years before thesurveys. In these locations at the eastern extent of the species range, we assessed what site factors were associ- ated with regeneration success. Whitebark pine regen- eration density was greater and seedlings were older in non-burned compared to burned areas. Within burns, north aspects had more regeneration than south aspects. Potential seed source densities and other species＇ regeneration were positively related to whitebark p^ne regeneration densities in burned areas. South facing slopes or grass covered areas may have either delayed or no regeneration of whitebark pine without the help of artificial planting.

关键词： recruitment Age structure White pineblister rust - Mountain pine beetle restoration

Lax-Oleinik-Type Formulas and Efficient Algorithms for Certain High-Dimensional Optimal Control Problems

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Communications on Applied Mathematics and Computation 2024年第2期6卷 1428-1471页

作者： Paula Chen Jerome Darbon Tingwei Meng Division of Applied Mathematics Brown UniversityProvidenceRIUSA Department of Mathematics UCLALos AngelesCAUSA

Two of the main challenges in optimal control are solving problems with state-dependent running costs and developing efficient numerical solvers that are computationally tractable in high *** this paper,we provide analytical solutions to certain optimal control problems whose running cost depends on the state variable and with constraints on the *** also provide Lax-Oleinik-type representation formulas for the corresponding Hamilton-jacobi partial differential equations with state-dependent ***,we present an efficient,grid-free numerical solver based on our representation formulas,which is shown to scale linearly with the state dimension,and thus,to overcome the curse of *** existing optimization methods and the min-plus technique,we extend our numerical solvers to address more general classes of convex and nonconvex initial *** demonstrate the capabilities of our numerical solvers using implementations on a central processing unit(CPU)and a field-programmable gate array(FPGA).In several cases,our FPGA implementation obtains over a 10 times speedup compared to the CPU,which demonstrates the promising performance boosts FPGAs can *** numerical results show that our solvers have the potential to serve as a building block for solving broader classes of high-dimensional optimal control problems in real-time.

关键词： Optimal control Hamilton-jacobi partial differential equations Grid-free numerical methods High dimensions Field-programmable gate arrays(FPGAs)

Deep resistivity "turnover" effect at oil generation "peak" in the Woodford Shale,Anadarko Basin,USA

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Petroleum Science 2019年第5期16卷 972-980页

作者： Ting Wang jacobi David College of resources and Environment Yangtze UniversityWuhan 430100China School of Geology and Geophysics University of OklahomaNormanOK 73019USA ConocoPhillips Company Houston 77079USA State Key Laboratory of Petroleum resources and Prospecting China University of PetroleumBeijing 102249China Key Laboratory of Exploration Technology for Oil and Gas research(Yangtze University) Ministry of EducationWuhan 430100China

The Devonian Woodford Shale in the Anadarko Basin is a highly organic,hydrocarbon source *** values of vitrinite reflectance(r_o)present in the Woodford Shale penetrated by 52 control wells were measured *** vitrinite reflectance values,when plotted against borehole resistivity for the middle member of the Woodford Shale in the wells,display a rarely reported finding that deep resistivity readings decrease as r_o increases when r_o is greater than 0.90%.This phenomenon may be attributed to that aromatic and resin compounds containing conjugated pi bonds generated within source rocks are more electrically conductive than aliphatic *** aromatic and resin fractions were generated more than aliphatic fraction when source rock maturity further increases beyond oil *** finding of the relationship between deep resistivity and r_o may re-investigate the previously found linear relationship between source rock formation and aid to unconventional play exploration.

关键词： resistivity log Source rock thermal maturity Vitrinite reflectance Woodford Shale

Characterizing Fracture Spatial Patterns by Using Semivariograms

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Acta Geologica Sinica(English Edition) 2002年第1期76卷 89-99页

作者：许建东 LIN Chiente r.D.jacobi Institute of Geology China Seismological Bureau Beijing 100029 China KAO YUAN Institute of Technology Kaohsiung Taiwan China Department of Geology 876 NSM Complex State University of New York at Buffalo NY 14260 USA

Semivariogram is applied to fracture data obtained from detailed scanlinesurveys of nine field sites in western New York, USA in order to investigate the spatial patterns ofnatural fractures. The length of the scanline is up to 36 m. How both fracture spacing and fracturelength vary with distance is determined through semivariogram calculations. In this study, theauthors developed a FOrTrAN program to resample the fracture data from the scanline survey. Bycalculating experimental semivariogram, the authors found five different types of spatial patternsthat can be described by linear, spherical, reversed spherical, polynomial I (for aO) models, of which the last three arc newly proposed in this study. Thewell-structured semivariograms of fracture spacing and length indicate that both the location of thefractures and the length distribution within their structure domains are not random. The results ofthis study also suggest that semivariograms can provide useful information in terms of spatialcorrelation distance for fracture location and fracture length. These semivariograms can also beutilized to design more efficient sampling schemes for further surveys. as well as to define thelimits of highly probable extrapolation of a structure domain.

关键词： fracture pattern semivariogram fracture spacing fracture length

Estimation of 2-D and 3-D Fracture Densities from 1-D Data-Experimental and Field results

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Acta Geologica Sinica(English Edition) 2003年第4期77卷 491-503页

作者： XUJiandong robertD.jacobi InstituteofGeology ChinaSeismologicalBureauBeijing100029China DepartmentofGeology StateUniversityofNewYorkatBuffaloNY14260USA

2-D and 3-D densities of fractures are commonly used in mining safety design, natural gas and oil production in fractured reservoirs, and the characterization of subsurface flow and transportation systems in fractured rocks. However, many field data sets are collected in 1-D frequency (f) (e.g., scanlines and borehole data). We have developed an ArC/ INFO-based technology to calculate fracture frequency and densities for a given fracture network. A series of numerical simulations are performed in order to determine the optimal orientation of a scanline, along which the maximum fracture frequency of a fracture network can be obtained. We calculated the frequency (f) and densities (both D1 and D2) of 36 natural fracture trace maps, and investigated the statistical relationship between fracture frequency and fracture density D1, i.e. D1=1.340f+ 0.034. We derived analytical solutions for converting dimensional density (D1) to non-dimensional densities (D2 and D3) assuming that fracture length distribution follows an exponential or power law. A comparison between observed and calculated results based on the equations we developed shows that (1) there exists a linear relationship between fracture frequency and fracture density (D1), and this relationship can be used to estimate fracture density (D1) if the fracture frequency is determined from a scanline survey or from borehole data; (2) the analytical solutions we derived can accurately determine the non-dimensional 2-D fracture density (D2) in practice and 3-D fracture density (D3) in theory if the fracture length distribution function is assumed.

关键词： fracture frequency fracture density fracture network

Heart rate Variability from Underwater Spiroergometry:How Meaningful?

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Journal of Science in Sport and Exercise 2023年第2期5卷 116-122页

作者： Andreas Koch Fabian Möller Elena jacobi Thomas Muth Clark Pepper Uwe Hoffmann Jochen D.Schipke German Naval Medical Institute Maritime MedicineKronshagenGermany Department of Exercise Physiology Institute of Exercise Training and Sport InformaticsGerman Sport University CologneCologneGermany Institute of Occupational Social and Environmental MedicineHeinrich-Heine-UniversityDüsseldorfGermany Department of Neurology Johanna Etienne HospitalNeussGermany Forschungsgruppe Experimentelle Chirurgie Universitäts-Klinikum DüsseldorfMoorenstrasse 540225 DüsseldorfGermany

Cardiovascular fitness of divers is overwhelmingly performed using bicycle ergometry.A more sport-specific alternative presents fit2dive,an underwater spiroergometry *** of this exploratory study:using fit2dive to investigate the diagnostic value of measures of heart rate variability(HrV)after markedly increasing physical *** scuba divers employed the fit2dive system and increased fin-swimming speed until *** gas consumption(VE)and heart rate(Hr)were measured.A three-lead ECG was recorded to analyze for time and frequency domain *** increased from 16.5±6.5 to 68.3±26.6 L/*** increased from 96±13 beats/min(mean±SD)at rest to 170±14 beats/min before *** variability(SDNN:132±42 vs.54±17 ms)decreased along with two measures of parasympathetic activity(rMSSD:59±31 vs.24±16 ms;pNN50:22%±12%vs.3%±3%).Measures from the frequency domain decreased[low frequency(LF):3167±2651 vs.778±705 ms_(2)]or remained unaltered[high frequency(HF):885±652 vs.431±463 ms^(2)].Thus,LF/HF decreased from 4.3±2.3 to 2.5±*** sports-specific fit2dive can help assessing diving fitness by employing HrV ***,this study supports the view that these measures much depend on ***,HrV measures regarding altered autonomic control during exercise will lead to serious misinterpretation:as Hr increases,variability decreases.

关键词： Scuba diving Physical fitness Heart rate Heart rate variability Autonomic nervous system

Transplacental induction of fatty acid oxidation in term fetal pigs by the peroxisome proliferator-activated receptor alpha agonist clofibrate

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Journal of Animal Science and Biotechnology 2016年第3期7卷 341-352页

作者： Xi Lin Sheila jacobi Jack Odle Laboratory of Developmental Nutrition Department of Animal SciencesNorth Carolina State University

Background： To induce peroxisomal proliferator-activated receptor α（PPArα） expression and increase milk fat utilization in pigs at birth, the effect of maternal feeding of the PPArα agonist, clofibrate（2-（4-chlorophenoxy）-2-methyl-propanoic acid, ethyl ester）, on fatty acid oxidation was examined at ful-term delivery（0 h） and 24 h after delivery in this *** group of pigs（n = 10） was delivered from pregnant sows fed a commercial diet with or without 0.8% clofibrate for the last 7 d of gestation. Blood samples were col ected from the utero-ovarian artery of the sows and the umbilical cords of the pigs as they were removed from the sows by C-section on day 113 of ***： HPLC analysis identified that clofibric acid was present in the plasma of the clofibrate-fed sow（~4.2 μg/m L）and its offspring（~1.5 μg/m L）. Furthermore, the maternal-fed clofibrate had no impact on the liver weight of the pigs at 0 h and 24 h, but hepatic fatty acid oxidation examined in fresh homogenates showed that clofibrate increased（P 〈 0.01）^14C-accumulation in CO2 and acid soluble products 2.9-fold from [1-^14C]-oleic acid and 1.6-fold from[1-^14C]-lignoceric acid respectively. Correspondingly, clofibrate increased fetal hepatic carnitine palmitoyltransferase（CPT）and acyl-Co A oxidase（ACO） activities by 36% and 42% over controls（P 〈 0.036）. The m rNA abundance of CPT I was 20-fold higher in pigs exposed to clofibrate（P 〈 0.0001） but no differences were detected for ACO and PPArα m rNA between the two ***： These data demonstrate that dietary clofibrate is absorbed by the sow, crosses the placental membrane, and enters fetal circulation to induce hepatic fatty acid oxidation by increasing the CPT and ACO activities of the newborn.

关键词： Clofibrate Fatty acid oxidation Pigs Placenta transfer

regulation of axonal remodeling following spinal cord injury

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Neural regeneration research 2015年第10期10卷 1555-1557页

作者： Anne jacobi Florence M.Bareyre Institute of Clinical Neuroimmunology Ludwig-Maximilians Universit?t München Munich Cluster of Systems Neurology (Sy Nergy)

Central nervous system injuries,such as spinal cord injury（SCI）,are a leading cause of disability in young *** generally have severe clinical consequences and often lead to loss of motor or sensory input below the s... 详细信息

关键词： regulation of axonal remodeling following spinal cord injury STAT FGFr Figure CST

Fractal and Multifractal Propertiesof the Spatial Distribution of Natural Fractures——Analyses and Applications

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Acta Geologica Sinica(English Edition) 1999年第4期73卷 477-487页

作者： XU Jiandong QU Guosheng robert D. jacobi Institute of Geology China Seismological Bureau Beijing 100029 PRC Department of Geology State University of New York at Buffalo USA

The Cantor's dust theory is applied to investigate the scaling properites of the spatial distribution of natural fractures obtained from detailed scanline surveys of 27 field sites in the Appalachian Plateau of western New York, USA. The results obtained in this study indicate: 1) fracture spacing is characterized by fractal and multifractal properties. On small scales analyses yield an average fractal dimension of 0.15, which suggests a very high degree of clustering. In contrast, on large scales, fractures tend to be more regular and evenly distributed with an average fracture dimension of 0.52; 2) fractal dimension varies with different sets in different orientations, which can be attributed to interactions between pre-existing fractures and younger ones, as well as variations of the intensity of the stresses under which the fractures were formed; 3) a time sequence of fracture set formation can be proposed based on fractal and multifractal analyses, which consists of (from old to young): N-S, NW, ENE, and NE-striking sets. This time sequence is confirmed by the study of the abutting relationships of different fracture sets observed in the field.

关键词： fractal multifractal fracture

Vibrational Analysis of Oxygen Adsorption on Cs and CO Coadsorbate Precovered ru(0001)Surface

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Chinese Physics Letters 1999年第6期16卷 428-430页

作者：何丕模 Karl jacobi Department of Physics Zhejiang UniversityHangzhou 310027 Fritz-Haber-Institut der Max-Planck-Gesellschaft Faradayweg 4-6D-14195 BerlinGermany

Vibrational analysis of oxygen adsorption on the Cs and CO coadsorbate precovered ru(0001)surface was carried out by means of high-resolution electron energy loss *** submonolayer Cs coverages on ru(0001)j an appropriate amount of CO adsorption leads to formation of(2x2)-Cs+2CO *** oxygen adsorption on this Cs and CO coadsorbate precovered surface results in a remarkable change of high-resolution electron energy loss *** loss peak of C-O stretch mode for 2x2 island species decreases in intensity,which is accompanied by appearance of new bands at about 87 and 240 *** results show that Cs adatoms and CO molecules are rearranged upon oxygen adsorption,and are correlated with coexistence of bare surface CO and a mixed phase of Cs,CO,and O.

关键词： spectroscopy. adsorption Adsorption