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Bioassessment of the rio Grande Upstream and Downstream of Los Alamos National Laboratory,New Mexico, USA

Journal of Environmental Protection 2012年第11期3卷 1596-1605页

作者： Philip r. Fresquez Gerald Z. jacobi Environmental Stewardship Group Los Alamos National Laboratory Los Alamos USA jacobi and Associates Santa Fe USA

Benthic macroinvertebrates (aquatic insects) were collected from the rio Grande upstream and downstream of Los Alamos Canyon (LAC), a major drainage that crosses Los Alamos National Laboratory (LANL) lands in northern New Mexico, USA. LAC contains legacy waste, including radionuclides and polychlorinated biphenyls, and occasionally discharges storm water and snowmelt flows to the rio Grande. The rio Grande is the major waterway that flows southward across the state. In 2009, rock baskets were placed in waters 61- to 76-cm-deep within each reach (five per reach), and, after approximately 6 weeks of colonization, the rock baskets were retrieved. All samples were sorted completely and organisms were identified to the lowest possible taxonomic level. Both reaches in 2009 were dominated by the collector filtering net-spinning caddisfly, Hydropsyche occidentalis. In 2011, benthic macroinvertebrates were collected using D kick nets from shallow riffle locations (15- to 31-cm depth) from each reach (six per reach). These samples were collected after post- (Las Conchas) fire flooding events moved sediment and ash through the two study areas—the downstream reach, however, was affected by higher flows and greater number of flooding events than those affecting the upstream reach. Each kick net sample consisted of ten 1-m (kick) samples. The 10 subsamples were composited and organisms were picked from randomly selected cells in a sorting pan until 500 organisms had been identified to the lowest possible taxonomic level. Both reaches in 2011 were dominated by the collector-gathering mayfly, Baetis tricaudatus. A bioassessment of the downstream reach compared with the upstream (reference) reach was conducted by scoring 10 metrics related to the structure and function of the benthic macroinvertebrate community. While 2009 ranked at the highest level (nonimpaired), 2011 ranked a level lower (slightly impaired). The slightly lower bioassessment score of the downstream reach in 2011 m

关键词： Benthic Macroinvertebrates Water Quality radionuclides Polychlorinated Biphenyls Mercury rio Grande Monitoring

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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)

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适于重油运行的组合活塞

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柴油机 1992年第4期14卷 23-29页

作者： D.rhrle jacobi 张厚

1 前言回顾70年代后期,当时只在高功率装置范围内为燃用重油经济运行的柴油机规定了比较低的极限。80年代初期,由于原油市场形势的变化促使重油也用于较小型的柴油机。为了从较低的燃料费用中得到好处,不得不使这种发动机与更高的燃烧... 详细信息

1 前言回顾70年代后期,当时只在高功率装置范围内为燃用重油经济运行的柴油机规定了比较低的极限。80年代初期,由于原油市场形势的变化促使重油也用于较小型的柴油机。为了从较低的燃料费用中得到好处,不得不使这种发动机与更高的燃烧压力和温度相适应。同时,必须对锻制钢顶锻制轻合金裙的组合式活塞(图1、2)提出更高的要求。这种活塞已经在烧粗柴油和重油的中速柴油机上成功地使用了20多年,今后还将如此。

关键词：活塞组合式重油运行

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ru(0001)表面上O-ru伸缩振动的覆盖度依赖特性

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物理学报 1999年第2期48卷 284-288页

作者：何丕模 jacobi,K 浙江大学物理系

在Ｒｕ（０００１）表面上，通过氧气以及二氧化氮气体的分解吸附，制备了具有不同氧覆盖度的氧覆盖层．高分辨电子能量损失谱的测量表明，ＯＲｕ伸缩振动具有强烈的覆盖度依赖特性。

关键词：氧覆盖层化学吸附吸附 ru(0001) 伸缩振动

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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

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Dietary arachidonate in milk replacer triggers dual benefits of PGE2 signaling in LPS-challenged piglet alveolar macrophages

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Journal of Animal Science and Biotechnology 2019年第2期10卷 435-448页

作者： Kathleen r.Walter Xi Lin Sheila K.jacobi Tobias Kaser Debora Esposito Jack Odle Department of Animal Science Plants for Human Health InstituteNorth Carolina State UniversityKannapolisNorth CarolinaUSA Department of Animal Science North Carolina State UniversityRaleighNorth CarolinaUSA Department of Animal Science Ohio State UniversityColumbusOhioUSA Department of Population Health and Pathobiology College of Veterinary MedicineNorth Carolina State UniversityRaleighNorth CarolinaUSA.

Background: respiratory infections challenge the swine industry, despite common medicinal practices. The dual signaling nature of PGE2(supporting both inflammation and resolution) makes it a potent regulator of immune cell function. Therefore, the use of dietary long chain n-6 PUFA to enhance PGE2 effects merits ***: Day-old pigs(n = 60) were allotted to one of three dietary groups for 21 d(n = 20/diet), and received either a control diet(CON, arachidonate = 0.5% of total fatty acids), an arachidonate(ArA)-enriched diet(LC n-6,ArA = 2.2%), or an eicosapentaenoic(EPA)-enriched diet(LC n-3, EPA = 3.0%). Alveolar macrophages and lung parenchymal tissue were collected for fatty acid analysis. Isolated alveolar macrophages were stimulated with LPS in situ for 24 h, and m rNA was isolated to assess markers associated with inflammation and eicosanoid *** media were collected to assess PGE2 secretion. Oxidative burst in macrophages was measured by: 1)oxygen consumption and extracellular acidification(via Seahorse), 2) cytoplasmic oxidation and 3) nitric oxide production following 4, 18, and 24 h of LPS ***: Concentration of ArA(% of fatty acids, w/w) in macrophages from pigs fed LC n-6 was 86% higher than CON and 18% lower in pigs fed LC n-3(P rNA(P retion(P re higher in LC n-6 PAM vs. CON. However, ALOX5 abundance was1.6-fold lower than CON. Macrophages from CON and LC n-6 groups were 4-fold higher in ALOX12/15 abundance(P red to LC n-3. Oxygen consumption and extracellular acidification rates increased over 4 h following LPS stimulation(P regardless of treatment. Similarly, increases in cytoplasmic oxidation(P ric oxide production(P re observed after 18 h of LPS stimulation but were unaffected by ***: We infer that enriching diets with arachidonic acid may be an ef

关键词： Arachidonic acid Cyclooxygenase Eicosanoid Eicosapentaenoic acid Inflammation Lipid mediator class switch LPS Lipoxin Porcine alveolar macrophage

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氧在Cs和CO共吸附物预覆盖的ru(0001)表面上吸附的高分辨电子能量损失谱研究

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Chinese Journal of Chemical Physics 1999年第5期12卷 607-614页

作者：何丕模 K.jacobi 浙江大学物理系 FritZ-Haber-Institut der MPG Faradarweg 4-6D-14195 BerlinGermany

对氧在Cs和CO共吸附物顶覆盖的ru（0001）上的吸附进行了高分辨电子能量损失谱（HrEELS）研究。在没有Cs预覆差的情况下，氧在CO预覆盖的ru（0001）上吸附形成CO＋O的混合相，并引起CO吸附表面链弱化；在低覆差度Cs预覆盖的ru（0001）... 详细信息

对氧在Cs和CO共吸附物顶覆盖的ru（0001）上的吸附进行了高分辨电子能量损失谱（HrEELS）研究。在没有Cs预覆差的情况下，氧在CO预覆盖的ru（0001）上吸附形成CO＋O的混合相，并引起CO吸附表面链弱化；在低覆差度Cs预覆盖的ru（0001）上，适量的CO吸附导致形成（2×2）－Cs＋2CO的共吸附畴，接着进行O_2离解吸附；HrEEL谱发生了显著变化，其结果表明随着氧的吸附，Cs和CO共吸附畴消失，Cs原子和CO分子重整其吸附位置，部分CO转变成为裸露表面CO态，部分CO很可能与Cs原子及O原子形成混合相；在低覆盖度Cs以及单层Cs预覆盖的情况下，CO饱和吸附的表面，对O_2离解吸附而言，不再具有活性。

关键词：钌表面共吸附碱金属助催化剂氧覆盖层

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Prevalence and risk factors associated with metabolic dysfunctionassociated steatohepatitis in patients with Helicobacter pylori infection: A population-based study

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World Journal of Hepatology 2024年第10期16卷 1169-1176页

作者： rashid Abdel-razeq Lynn Bitar Elio r Bitar Chidera Onwuzo Mohamad-Noor Abu-Hammour Barish Eren Islam Mohamed Adejoke Johnson Antoine Boustany Somtochukwu Onwuzo Imad Asaad Department of Internal Medicine Cleveland Clinic FoundationClevelandOH 44111United States Faculty of Medicine Saint Joseph University of BeirutBeirut 11042020Lebanon Faculty of Medicine American University of BeirutBeirut 11072020Lebanon Department of Medicine&Surgery General Hospital Lagos IslandLagos Island 101223LagosNigeria Department of Internal Medicine Jacobi Medical Center/North Central Bronx HospitalBronxNY 10461United States Division of Gastroenterology Department of Internal MedicineUniversity of Florida College of MedicineJacksonvilleFL 32209United States Department of Gastroenterology Allegheny General HospitalPittsburghPA 15212United States Department of Gastroenterology Firelands HealthSanduskyOH 44870United States

BACKGrOUND Helicobacter pylori(***)is associated with the development of gastrointestinal disorders ranging from gastritis to gastric *** evidence of the association between metabolic dysfunction-associated steatohepatitis(MASH)and *** infection in the literature is ***,we aim to evaluate the risk of developing MASH in patients who have had a diagnosis of *** infection independently of any confounding *** To evaluate the risk of developing MASH in patients who have had a diagnosis of *** *** This study used a validated multicenter research database of over 360 hospitals across 26 healthcare systems across the United States from 1999 to *** regression analysis assessed the risk of developing MASH,adjusting for confounders including *** infection,obesity,type 2 diabetes,hypertension,dyslipidemia,and male gender.A two-sided P valuered as statistically significant,and all statistical analyses were performed using r version 4.0.2(r Foundation for Statistical Computing,Vienna,Austria,2008).rESULTS A total of 79476132 individuals were screened in the database and 69232620 were selected in the final analysis after accounting for inclusion and exclusion ***(14.30%),patients with hyperlipidemia(70.35%),hypertension(73.86%),diabetes mellitus type 2(56.46%),and obese patients(58.15%)were more common in patients with MASH compared to *** a multivariate regression analysis,the risk of MASH was increased in diabetics[odds ratio(Or):3.55;95%CI:3.48-3.62],obese(Or:5.93;95%CI:5.81-6.04),males(Or:1.49;95%CI:1.46-1.52),individuals with hyperlipidemia(Or:2.43;95%CI:2.38-2.49)and *** infection(Or:2.51;95%CI:2.31-2.73).CONCLUSION This is the largest population-based study in the United States illustrating an increased prevalence and odds of developing MASH in patients with *** infection after adjusting for risk factors.

关键词： Metabolic dysfunction-associated steatohepatitis Metabolic dysfunction-associated steatotic liver disease Helicobacter Pylori Cirrhosis Liver

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Enteroclysis:Current clinical value

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World Journal of radiology 2013年第7期5卷 253-258页

作者： Adel Maataoui Thomas J Vogl Volkmar.jacobi M Fawad Khan Institute for Diagnostic and Interventional radiology Goethe University 60590 Frankfurt am Main Germany

AIM: To retrospectively analyze changes in clinical indication, referring medical specialty and detected pathology for small bowel double-contrast examinations. METHODS: Two hundred and forty-one (n = 143 females; n = 98 males; 01.01.1990-31.12.1990) and 384 (n = 225 females; n = 159 males; 01.01.2004-31.12.2010) patients underwent enteroclysis, respectively. All exami- nations were performed in standardized double-contrast technique. After placement of a nasojejunal probe distal to the ligament of Treitz, radiopaque contrast media followed by Xray negative distending contrast media were administered. Following this standardized projections in all four abdominal quadrants were acquired. Depending on the detected pathology further documentation was carried out by focused imaging. Examination protocols were reviewed and compared concerning requesting unit, indication and final report. rESULTS: Two hundred and forty-one examinations in 1990 faced an average of 55 examinations per year from 2004-2010. There was an increase of examinations for gastroenterological (33.6% to 64.6%) andpediatric (0.4% to 7.8%) indications while internal (29.0% to 6.0% for inpatients and from 16.6% to 9.1% for outpatients) and surgical (12.4% to 7.3%) referrals significantly decreased. 'Follow-up of Crohn’s disease' (33.1%) and 'bleeding/tumor search' (15.1%) represented the most frequent clinical indications. A total of 34% (1990) and 53.4% (2004-2010) examinations yielded pathologic findings. In the period 01.01.2004 -31.12.2010 the largest proportion of pathological findings was found in patients with diagnosed Crohn’s disease (73.5%), followed by patients with abdominal pain (67.6% with history of surgery and 52.6% without history of surgery), chronic diarrhea (41.7%), suspected Crohn’s disease (39.5%) and search for gastrointestinal bleeding source/tumor (19.1%). The most common pathologies diagnosed by enteroclysis were 'changes in Crohn’s disease' (25.0%) and 'adhesions /strictures' (

关键词： Inflammatory bowel diseases Fluoroscopy Double-Balloon enteroscopy Magnetic resonance imag- ing Helical computed tomography

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Effects of the Catalytic System MoO<sub>2</sub>(acac)<sub>2</sub>-TBHP in Polyisoprene Epoxidation Using Experimental Design

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Journal of Materials Science and Chemical Engineering 2020年第3期8卷 39-51页

作者： José r. Gregório Elisa Barbosa-Coutinho Annelise E. Gerbase Márcia Pires Fortes Ferreira Marly A. M. jacobi Instituto de Química Universidade Federal do Rio Grande do Sul Porto Alegre RS Brazil

The epoxidation of polydienes yields materials with improved properties, which can be tuned by the control of the epoxidation degree. In this work, we retake a known process, the epoxidation of polyisoprene, by a different approach, in which the quantification of parameters influencing the epoxidation, such as temperature, oxidant and catalyst concentration, and reaction time degree is evaluated. We measured the influence of each parameter, allowing anyone who aims a polymer with a certain degree of epoxidation to choose which conditions are best suitable for reaching his goal.

关键词： Epoxidation Molybdenum Polyisoprene Experimental Design

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