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Particuology 2020年第2期18卷 40-47页

作者： Xiaoliang Wang SKent Hoekman Yang Han Judith CChow John G.Watson Xiaomeng Wu Ye Wu dennis Schuetzle Robert Schuetzle Desert Research Institute 2215 Raggio PkwyRenoNV 89512USA School of Environment Tsinghua UniversityBeijing 100084China Greyrock Energy Inc.2020 L StreetSuite 120SacramentoCA 95811USA

Vehicle exhaust and transported biomass burning emissions are important air pollution sources in many urban areas,and domestic cooking with biomass fuels causes indoor air pollution in many rural *** agricultural waste-generated synthetic fuels can reduce emissions both from vehicles and biomass *** estimate the potential benefits of synthetic diesel in Beijing,the emission factor model for the Beijing vehicle fleet was applied to estimate exhaust emissions for the 2015-2030 *** with 100%petroleum diesel,a 20%synthetic diesel blend reduced diesel fleet emissions by 24%for carbon monoxide,30%for total hydrocarbons,5.5%for nitrogen oxides,and 19%for fine particulate matter with an aerodynamic diameter of≤2.5μm(Pm2.5)while using 100%synthetic diesel decreased emissions by 36%for carbon monoxide,48%for total hydrocarbons,10%for nitrogen oxides,and 34%for *** use of biomass for producing synthetic fuels rather than burning in the field also reduces air *** 60g of Pm2.5 agricultural open-field burning emissions are avoided per liter of synthetic fuel *** solid crop residues with synthetic liquid fuels in household cooking would reduce Pm2.5 emissions by more than 90%.

关键词： Pm2.5 Air pollution Vehicle emission Biomass burning Synthetic fuel Agricultural biomass

The Demise of Knowledge management Executive Leadership： An Empirical Study of Leading Companies That Have Changed Their Knowledge management Strategies？

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management Studies 2016年第5期4卷 227-236页

作者： Harold dennis Harlow Wingate University Wingate USA

Knowledge management is increasingly under attack to show returns on investments and profitable business outcomes. While many companies retain their executive leadership as chief knowledge officers （CKOs） and vice presidents of knowledge management, the trend toward appointing CKOs that developed in the late 1990＇s has been reversed at many companies and a new trend is to assign the strategic functions of knowledge management to the chief information officer （CIO）. This new strategic approach has many ramifications that determine if the firm will be able to meet not only short-term objectives but firm mission strategic outcomes as well. This paper researches over 100 knowledge management executives respondents in a broad cross-section of medium and large US industries and organizations to question why the shift is occurring and what the strategic basis is for this shift？ The results of this study clearly show that there are pros and cons to make this strategic shift and that many firms are doing so with little actual factual knowledge of the strategic effects on performance or intellectual capital formation. This paper and empirical ftrm performance and patent research is designed to give that top manager （CEO） the appropriate information to make rational decisions based on facts when considering eliminating or consolidation of CKO into the CIO function. Decisions on CLO and CKO positions should be based on the fu＇m related performance in both measurable intellectual property and financial results. The results are presented and summarized and the statistical methodology of regression and correlation are used in this paper.

关键词： knowledge management strategy executive knowledge leadership

Histone Acetylation, VERNALIZATION INSENSITIVE 3, FLOWERING LOCUS C, and the Vernalization Response

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molecular Plant 2009年第4期2卷 724-737页

作者： Donna m. Bond Elizabeth S. dennis Barry J. Pogson E. Jean Finnegan CSIRO Plant Industry Canberra Australia ARC Centre of Excellence in Plant Energy Biology School of Biochemistry and Molecular Biology Australian National University Canberra Australia

The quantitative induction of VIN3 by low temperatures is required for PRC2 repression of FLC and promotion of flowering （vernalization） in Arabidopsis. Histone acetylation, a chromatin modification commonly associated with gene transcription, increased on VIN3 chromatin in two spatially and temporally distinct phases in response to low temperatures. During short-term cold exposure, histone H3 acetylation at the transcription start site rapidly increased, implying that it is required for VlN3 induction. Subsequent changes in histone H3 and H4 acetylation occurred following continued VIN3 transcription during prolonged cold exposure. members of the SAGA-like transcriptional adaptor complex, including the histone acetyltransferase GCNS, which induces expression of the cold acclimation pathway genes, do not regulate VlN3 induction during cold exposure, indicating that the cold acclimation pathway and the cold-induction of VlN3 are regulated by different transcriptional mechanisms. mutations in the other 11 histone acetyltransferase genes did not affect VlN3 induction. However, nicotinamide, a histone deacetyiase inhibitor, induced VIN3 and altered histone acetylation at the VIN3 locus. VIN3 induction was proportional to the length of nicotinamide treatment, which was associated with an early-flowering phenotype and repression of FLC. However, unlike vernalization, the repression of FLC was independent of VIN3 activity. Nicotinamide treatment did not cause a change in the expression of any genes in the autonomous pathway or members of the PRC2 complex, the well characterized repressors of FLC. Our data suggest that FLC is repressed via a novel pathway involving the SIR2 class of histone deacetylases.

关键词： Cold acclimation histone acetyltransferase histone deacetylase SIR2 nicotinamide.

Comparison of Cu−Al−Ni−mn−Zr shape memory alloy prepared by selective laser melting and conventional powder metallurgy

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Transactions of Nonferrous metals Society of China 2020年第12期30卷 3322-3332页

作者： dennis GERA Jonadabe SANTOS Cláudio SKImINAmI Piter GARGARELLA Postgraduate Program in materials Science and Engineering Federal University of São CarlosSão CarlosBrazil materials Engineering Department Federal University of São CarlosR.Washington Luískm 235-SP 310São CarlosBrazil

This work aimed to investigate and critically analyze the differences in microstructural features and thermal stability of Cu−11.3Al−3.2Ni−3.0mn−0.5Zr shape memory alloy processed by selective laser melting(SLm)and conventional powder *** specimens were produced by sintering 106−180μm pre-alloyed powders under an argon atmosphere at 1060°C without secondary *** specimens were consolidated through melting 32−106μm pre-alloyed powders on a Cu−10Sn *** properties were measured through Vickers hardness *** scanning calorimetry was conducted to assess the martensitic transformation temperatures.X-ray diffraction patterns were collected to identify the metallurgical *** and scanning electron microscopy was used to analyze the microstructural features.b′1 martensite was found,irrespective of the processing route,although coarser martensitic variants were present in *** conventional powder metallurgy samples,intergranular eutectoid constituents and stabilized austenite also formed at room ***-specimens showed similar average hardness values to the SLm-specimens,albeit with high standard deviation linked to the *** specimens processed by SLm showed reversible martensitic transformation(T0=171°C).Pm-processed specimens did not show shape memory effects.

关键词： shape memory alloys powder metallurgy additive manufacturing selective laser melting Cu-based alloys

Antithetic Power Transformed Random Variables in Computer Simulations: An Error Correction mechanism

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Journal of Applied mathematics and Physics 2023年第6期11卷 1707-1727页

作者： dennis Ridley Pierre Ngnepieba School of Business & Industry Florida A&M University Tallahassee FL USA Department of Scientific Computing Florida State University Tallahassee FL USA Department of mathematics Florida A&M University Tallahassee FL USA

A traditional method of monte Carlo computer simulation is to obtain uniformly distributed random numbers on the interval from zero to one from a linear congruential generator (LCG) or other methods. Random variates can then be obtained by the inverse transformation technique applied to random numbers. The random variates can then be used as input to a computer simulation. A response variable is obtained from the simulation results. The response variable may be biased for various reasons. One reason may be the presence of small traces of serial correlation in the random numbers. The purpose of this paper is to introduce an alternative method of response variable acquisition by a power transformation applied to the response variable. The power transformation produces a new variable that is negatively correlated with the response variable. The response variable is then regressed on its power transformation to convert the units of the power transformed variable back to those of the original response variable. A weighted combination of these two variables gives the final estimate. The combined estimate is shown to have negligible bias. The correlations of various antithetic variates obtained from the power transformation are derived and illustrated to provide insights for this research and for future research into this method.

关键词： Inverse Correlation Variance Reduction Antithetic Random Variates Simulation model Bias Bias Reduction

mycophenolate mofetil for drug-induced vanishing bile duct syndrome

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World Journal of Gastroenterology 2007年第45期13卷 6087-6089页

作者： S Simona Jakab A Brian West dennis m meighan Robert S Brown Jr William B Hale Section of Gastroenterology Norwalk Hospital Norwalk CT 06856United States Department of Pathology New York UniversityNew York NY United States Center for Liver Disease and Transplantation New York-Presbyterian Hospital Columbia University College of Physicians and Surgeons New York NY United States

Amoxicillin/clavulanate is associated with liver injury, mostly of a cholestatic pattern. While outcomes are usually benign, progression to cirrhosis and death has been reported. The role of immunosuppressive therapy for patients with a protracted course is unclear. We report the case of an elderly patient who developed prolonged cholestasis secondary to amoxicillin/clavulanate. Vanishing bile duct syndrome was confirmed by sequential liver biopsies. The patient responded to prednisone treatment, but could not be weaned off corticosteroids, even when azathioprine was added. Complete withdrawal of both prednisone and azathioprine was possible by using mycophenolate mofetil, an inosine monophosphate dehydrogenase inhibitor. Sustained remission has been maintained for more than 3 years with low-dose mycophenolate mofetil.

关键词： Amoxicillin and clavulanate Drug-inducedcholestasis Ductopenia mycophenolate mofetil Vanishingbile duct syndrome

Randomized Constraint Limit Linear Programming in Risk management

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Journal of Applied mathematics and Physics 2020年第11期8卷 2691-2702页

作者： dennis Ridley Abdullah Khan School of Business and Industry Florida A & M University Tallahassee FL USA Department of Scientific Computing Florida State University Tallahassee FL USA School of Business Claflin University Orangeburg SC USA

Traditional linear program (LP) models are deterministic. The way that constraint limit uncertainty is handled is to compute the range of feasibility. After the optimal solution is obtained, typically by the simplex method, one considers the effect of varying each constraint limit, one at a time. This yields the range of feasibility within which the solution remains feasible. This sensitivity analysis is useful for helping the analyst get a feel for the problem. However, it is unrealistic because some constraint limits can vary randomly. These are typically constraint limits based on expected inventory. Inventory may fall short if there are overdue deliveries, unplanned machine failure, spoilage, etc. A realistic LP is created for simultaneously randomizing the constraint limits from any probability distribution. The corresponding distribution of objective function values is created. This distribution is examined directly for central tendencies, spread, skewness and extreme values for the purpose of risk analysis. The spreadsheet design presented is ideal for teaching monte Carlo simulation and risk analysis to graduate students in business analytics with no specialized programming language requirement.

关键词： Pedagogic Effectiveness of Big Data Analytics Linear Programming Stochastic Optimization Constraint Limit Profit Distribution and Risk monte Carlo Simulation

DECAY PROCESSES OF HIGH-FREQUENCY NONEQUILIBRIUm PHONONS IN PRASEODYmIUm-DOPED LASER CRYSTALS

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发光学报 1999年第2期 40-48页

作者： Wang Xiaojun a) dennis W m b) Yen W m b) a) (Department of Physics & Astronomy, Georgia Southern University, Statesboro, GA 30460, USA) b) (Department of Physics and Astronomy, The University of Georgia, Athens, GA 3

１ＩＮＴＲＯＤＵＣＴＩＯＮＩｎａｒｅａｌｃｒｙｓｔａｌｓｙｓｔｅｍ，ｔｈｅｌａｔｉｃｅｖｉｂｒａｔｉｏｎｓｗｉｌｎｏｔｂｅｔｈｅｅｉｇｅｎｓｔａｔｅｓｏｆｔｈｅｓｙｓ－ｔｅｍ，ｉ．ｅ．，ａｎｉｎｉｔｉａｌｙｍｏｎｏｃ... 详细信息

１ＩＮＴＲＯＤＵＣＴＩＯＮＩｎａｒｅａｌｃｒｙｓｔａｌｓｙｓｔｅｍ，ｔｈｅｌａｔｉｃｅｖｉｂｒａｔｉｏｎｓｗｉｌｎｏｔｂｅｔｈｅｅｉｇｅｎｓｔａｔｅｓｏｆｔｈｅｓｙｓ－ｔｅｍ，ｉ．ｅ．，ａｎｉｎｉｔｉａｌｙｍｏｎｏｃｈｒｏｍａｔｉｃｎｏｎｅｑｕｉｌｉ...

关键词： nonequilibrium phonons high frequency phonons lattice dynamics YAG YLF

Diffuse coronary artery vasospasm in a patient with subarachnoid hemorrhage: A case report

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World Journal of Cardiology 2020年第9期12卷 468-474页

作者： dennis Grewal Adeba mohammad Pooja Swamy Islam Abudayyeh mamas A mamas Purvi Parwani Division of Cardiology Department of CardiologyLoma Linda University Medical CenterLoma LindaCA 92354United States Keele Cardiovascular Research Group Centre for Prognosis ResearchInstitutes of Applied Clinical Science and Primary Care and Health SciencesKeele UniversityStoke on TrentManchester M139PTUnited Kingdom

BACKGROUND Coronary artery vasospasm(CAV)is a reversible,transient form of vasoconstriction with clinical manifestations ranging from stable angina to acute coronary syndromes(ACS).Vasospasm of epicardial coronary arteries or associated micro-vasculature can lead to total or subtotal occlusion and has been demonstrated in nearly 50%of patients undergoing angiography for suspected *** mechanism for CAV has been described in literature,but in a subgroup of patients presenting with intracranial hemorrhage,it appears to be *** patients tend to have electrocardiographic changes,elevation of cardiac biomarkers of injury and neurogenic stress *** SUmmARY A 44-year-old woman presented with severe headaches and tonic-clonic *** was found to have diffuse subarachnoid hemorrhage(SAH)requiring ventricular drain placement,coil embolization and induced *** subsequently developed chest pain with ST elevations in anterior precordial leads,elevated cardiac enzymes and apical ballooning with left ventricular ejection fraction of 35%on transthoracic *** angiogram revealed severe diffuse triple vessel stenoses secondary to CAV seen *** cardiac mRI notable for apical non-viability and scar *** This case highlights a unique etiology of acute myocardial infarction in a patient with SAH leading to ST elevations,diffuse triple vessel CAV and apical scar.

关键词： ST-elevation myocardial infarction Acute coronary syndrome Stress induced cardiomyopathy Coronary artery vasospasm Cerebral vasospasm Subarachnoid hemorrhage Case report

Development of the DayCent-Photo model and integration of variable photosynthetic capacity

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Frontiers of Earth Science 2018年第4期12卷 765-778页

作者： Jonathan R.STRAUBE maosi CHEN William J.PARTON Shinichi ASSO Yan-An LIU dennis S.OJImA Wei GAO USDA UV-B monitoring and Research Program Natural Resource Ecology LaboratoryColorado State UniversityFort CollinsCO 80521USA Natural Resource Ecology Laboratory.Colorado State University Fort CollinsCO 80523USA Key Laboratory of Geographic Information Science (ministry of Education) East China Normal UniversityShanghai 200241China School of Geographic Sciences East China Normal UniversityShanghai 200241China ECNU-CSU Joint Research Institute for New Energy and the Environment Shanghai 200062China Department of Ecosystem Science and Sustainability Colorado State UniversityFort CollinsCO 80523USA

We integrated a photosynthetic sub-model into the daily Century model (DayCent) to improve the estimations of seasonal changes in carbon fluxes at the Niwot Ridge LTER site and the Harvard forest LTER site (DayCent-Photo). The photosynthetic sub-model, adapted from the SIPNET/PnET family of models, includes solar radiation and vapor pressure deficit controls on production, as well as temperature and water stress terms. A key feature we added to the base photosynthetic equations is the addition of a variable maximum net photosynthetic rate (Amax). We optimized the parameters controlling photosynthesis using a variation of the metropolis-Hastings algorithm along with data-assimilation techniques. The model was optimized and validated against observed net ecosystem exchange (NEE) and estimated gross primary production (GPP) and ecosystem respiration (RESP) values for AmeriFlux sites at Niwot Ridge and Harvard forest. The inclusion of a variable Amax rate greatly improved model performance (NEE RmSE = 0.63 gC center dot m(-2), AIC = 2099) versus a version with a single Amax parameter (NEE RmSE = 0.74 gC center dot m(-2), AIC = 3724). DayCent-Photo was able to capture the inter-annual and seasonal flux patterns for NEE, GPP, ecosystem respiration (RESP), and daily actual evapotranspiration (AET), but tended to overestimate yearly NEE uptake. The DayCent-Photo model has been successfully set up to simulate daily NEE, GPP, RESP, and AET for deciduous forest, conifer forests, and grassland systems in the US using AmeriFlux data sets and has recently been improved to include the impact of UV radiation surface litter decay (DayCent-UV). The simulated influence of a variable Amax rate suggests a need for further studies on the process controls affecting the seasonal photosynthetic rates. The results for all of the forest and grassland sites show that maximum Amax values occurs early during the growing period and taper off toward the end of the growing season.

关键词： DayCent-Photo model seasonal maximum net photosynthetic rate net ecosystem exchange gross primary production UV radiation