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Open journal of Anesthesiology 2013年第3期3卷 168-169页

作者： chistopher.j. burnett Andrew j. White Marius D. Vulcan Division of Anesthesiology Scott & White Memorial Hospital Temple College of Medicine Texas A&M University College Station USA.

We present an interesting case report of a 49-year-old female who presented with symptoms of post-dural puncture headache following implantation of an intrathecal pain pump. Her history was complicated by previous multi-level spinal fusion with hardware. The patient was evaluated and felt to be a candidate for epidural blood patch, which she elected to proceed with. Under fluoroscopic guidance epidural blood patch was successfully performed. Immediately following the procedure the patient noted significant improvement in the headache and six hours following the procedure was headache free and remained so at follow up three weeks later.

关键词： Epidural Blood Patch Intrathecal Pain Pump Spinal Fusion

Stability Analysis and Performance Evaluation of Additive Mixed-Precision Runge-Kutta Methods

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Communications on Applied Mathematics and Computation 2024年第1期6卷 705-738页

作者： Ben burnett Sigal Gottlieb Zachary j.Grant Center for Scientific Computing and Data Science Research UMass DartmouthNorth DartmouthMassachusettsUSA CSME Michigan State UniversityEast LansingMichiganUSA

Additive Runge-Kutta methods designed for preserving highly accurate solutions in mixed-precision computation were previously proposed and *** specially designed methods use reduced precision for the implicit computations and full precision for the explicit *** this work,we analyze the stability properties of these methods and their sensitivity to the low-precision rounding errors,and demonstrate their performance in terms of accuracy and *** develop codes in FORTRAN and julia to solve nonlinear systems of ODEs and PDEs using the mixed-precision additive Runge-Kutta(MP-ARK)*** convergence,accuracy,and runtime of these methods are *** show that for a given level of accuracy,suitably chosen MP-ARK methods may provide significant reductions in runtime.

关键词： Mixed precision Runge-Kutta methods Additive methods Accuracy

NADPH oxidase： recent evidence for its role in erectile dysfunction

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Asian journal of Andrology 2008年第1期10卷 6-13页

作者： Liming jin Arthur L.burnett Department of Urology The James Buchanan Brady Urological Institute Johns Hopkins Medical Institutions Baltimore MD 21287 USA

Important roles for reactive oxygen species （ROS） in physiology and pathophysiology have been increasingly recognized. Under normal conditions, ROS serve as signaling molecules in the regulation of cellular functions. However, enhanced ROS production as a result of the activation of nicotinamide adenine dinucleotide phosphate （NADPH） oxidase contributes significantly to the pathogeneses of vascular diseases. Although it has become evident that increased ROS is associated with erectile dysfunction （ED）, the sources of ROS in the penis remain largely unknown. In recent years, emergent evidence suggests the possible role of NADPH oxidase in inducing ED. In this review, we examine the relationship between ROS and ED in different disease models and discuss the current evidence basis for NADPH oxidase-derive＇d ROS in ED.

关键词： reactive oxygen species erectile function superoxide penis nitric oxide

4D imaging of void nucleation,growth,and coalescence from large and small inclusions in steel under tensile deformation

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journal of Materials Science & Technology 2022年第28期123卷 168-176页

作者： Yi Guo Timothy L.burnett Samuel A.McDonald Michael Daly Andrew H.Sherry Philip j.Withers Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Henry Royce Institute Department of MaterialsUniversity of ManchesterM139PLUK European Synchrotron Radiation Facility(ESRF) 6 rue J Horowitz38000 GrenobleFrance National Nuclear Laboratory Chadwick HouseBirchwood ParkWarringtonWA36AEUK

Samples of SA508 grade 3 nuclear pressure vessel ferritic steel were subjected to tensile straining whilst being simultaneously imaged in 3D in real time using high resolution,high frame rate time-lapse synchrotron computed tomography(CT).This enabled direct observation of void development from nucleation,through growth to coalescence and final failure validating many inferences made post-mortem or by theoretical models,as well as raising new *** sparse,large inclusions were found to nucleate voids at essentially zero plastic strain(consistent with zero interfacial strength);these became increasingly elongated with *** contrast,a high density of small spherical voids were found to nucleate from the sub-micron cementite particles at larger strains(>200%)only in the centre of the necked(high triaxiality)*** interfacial strength approaching 2100 MPa was inferred and soon after their nucleation,these small voids coalesce to form internal microcracks that lead to the final failure of the *** surprisingly,under these conditions of generally low triaxial constraint the large voids are simply cut across and appear to play no significant role in determining the final *** implications of these results are discussed in terms of ductile fracture behaviour and the Gurson model for ductile fracture.

关键词： Void growth Ductile fracture Synchrotron X-ray tomography 4D imaging Bainitic steel

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重载流多芯电缆周围的磁场I.理论模型

上海交通大学学报 2002年第2期36卷 237-242页

作者：傅正财杜亚平 j.burnett 上海交通大学电力学院上海200030 香港理工大学屋宇设备工程学系

多芯电力电缆在低压配电系统中常被用作配电干线 .这种重载流电缆周围的极低频磁场可能干扰附近敏感电子设备的正常运行 ,甚至影响暴露于该场下的人体的健康 .为分析这种磁场的分布特性 ,建立了多芯电缆周围磁场的载流平行螺旋线模型 ,... 详细信息

多芯电力电缆在低压配电系统中常被用作配电干线 .这种重载流电缆周围的极低频磁场可能干扰附近敏感电子设备的正常运行 ,甚至影响暴露于该场下的人体的健康 .为分析这种磁场的分布特性 ,建立了多芯电缆周围磁场的载流平行螺旋线模型 ,并推导了周围磁场的简化计算公式 .基于所提出的理论模型对电缆周围磁场的特性进行了分析 ,发现在电缆的半径方向上磁场随距离衰减的速度大于指数衰减速度 .在平行于电缆轴线的直线上和在电缆的同轴圆周线上 ,磁场的幅值和相角都随观测点的位置周期变化 .理论计算结果表明 ,常用规格的多芯电力电缆在载额定电流的情况下 ,距电缆 2 m外空间中的磁场已小于有关国际标准的限值 .

关键词：重载流理论模型多芯电力电缆极低频磁场电磁兼容低压配电系统

Factors associated with increased incidence of severe toxicities following yttrium-90 resin microspheres in the treatment of hepatic malignancies

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World journal of Gastroenterology 2016年第10期22卷 3006-3014页

作者： john D Roberson II Andrew M Mc Donald Craig j Baden Chee Paul Lin Rojymon jacob Omer L burnett III School of Medicine University of Alabama at Birmingham Birmingham AL 35294-3412 United States Department of Radiation Oncology University of Alabama at Birmingham Birmingham AL 35233 United States Center for Clinical and Translational Science University of Alabama at Birmingham Birmingham AL 35205 United States

AIM: To further define variables associated with increased incidences of severe toxicities following administration of yttrium-90 (90Y) ***: Fifty-eight patients undergoing 79 treatments were retrospectively assessed for development of clinical and laboratory toxicity incidence following 90Y administration. Severe toxicity events were defined using Common Terminology Criteria for Adverse Events version 4.03 and defined as grade ≥ 3. Univariate logistic regression analyses were used to evaluate the effect of different factors on the incidence of severe toxicity events. Multicollinearity was assessed for all factors with P 90Y microsphere therapy.

关键词： Yttrium-90 microspheres Liver metastases Multivariate analysis Toxicity incidence Colorectal adenocarcinoma

Distal small bowel motility and lipid absorption in patients following abdominal aortic aneurysm repair surgery

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World journal of Gastroenterology 2006年第4期12卷 582-587页

作者： Robert j Fraser Marc Ritz Addolorata C Di Matteo Rosalie Vozzo Monika Kwiatek Robert Foreman Brendan Stanley jack Walsh jim burnett Paul jury john Dent Department of Medicine University of AdelaideSouth Australia Department of Gastroenterology Royal Adelaide HospitalAdelaide South Australia Vascular Unit Royal Adelaide Hospital AdelaideSouth Australia Gastrointestinal Investigation Unit Repatriation General Hospital Daw Park South Australia Vascular Unit Repatriation General Hospital Daw Park SouthAustralia

AIM： To investigate distal small bowel motility and lipid absorption in patients following elective abdominal aortic aneurysm （AAA） repair surgery, METHODS： Nine patients （aged 35-78 years; body mass index （BMI） range： 23-36 kg/m2） post-surgery for AAA repair, and seven healthy control subjects （20-50 years; BMI range： 21-29 kg/m^2） were studied, Continuous distal small bowel manometry was performed for up to 72 h, during periods of fasting and enteral feeding （Nutrison）. Recordings were analyzed for the frequency, odgin, length of migration, and direction of small intestinal burst activity. Lipid absorption was assessed on the first day and the third day post surgery in a subset of patients using the ^13C-triolein-breath test, and compared with healthy controls. Subjects received a 20-min intraduodenal infusion of 50 mL liquid feed mixed with 200μL ^13C-triolein. End-expiratory breath samples were collected for 6 h and analyzed for ^13CO2 concentration. RESULTS： The frequency of burst activity in the proximal and distal small intestine was higher in patients than in healthy subjects, under both fasting and fed conditions （P〈 0.005）. In patients there was a higher proportion of abnormally propagated bursts （71% abnormal）, which began to normalize by d 3 （25% abnormal） *** absorption data was available for seven patients on d 1 and four patients on d 3 post surgery. In patients, absorption on d 1 post-surgery was half that of healthy control subjects （AUC ^13CO2 1323±244 vs 2646±365; P〈0.05, respectively）, and was reduced to the one-fitch that of healthy controls by d 3 （AUC ^13CO2 470±832 vs 2646±365; P〈 0.05, respectively）. CONCLUSION： Both proximal and distal small intestinal motor activity are transiently disrupted in critically ill patients immediately after major surgery, with abnormal motility patterns extending as far as the ileum. These motor disturbances may contribute to impaired absorption of enteral nutrition, especially when intralumi

关键词： Critical illness Small intestine Motility Lipid absorption

Oxide-supported metal catalysts for anaerobic NAD+regeneration with concurrent hydrogen production

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Chinese Chemical Letters 2024年第2期35卷 263-267页

作者： jianwei Li joseph W.H.burnett Claudia Martinez Macias Russell F.Howe Xiaodong Wang Chemical Engineering School of EngineeringLancaster UniversityLancaster LA1 4YWUnited Kingdom Chemistry Department University of AberdeenAberdeen AB24 3UEUnited Kingdom

We report SiO_(2)-supported monometallic Pt,Pd,Au,Ni,Cu and Co catalysts for proton-driven NAD+regeneration,co-producing H_(2).All metals are fully selective to NAD+where the order of turnover frequencies(Pt>Pd>Cu>Au,Ni and Co)coincides with those otherwise observed in electrochemical hydrogen evolution *** has revealed that NADH is capable of converting the metal sites into a“cathode”without an external potential and the NADH to NAD+reaction involves transferring electron and hydrogen atom ***-deficient Ptδ+(on CeO_(2))enhances TOF and the heterogeneous Pt/CeO_(2) catalyst is recyclable without losing any activity/selectivity.

关键词： NAD+regeneration Heterogeneous catalyst Hydrogenase mimic Hydrogen binding energy Hydrogen production

A Lysozyme Concentration, pH, and Time-Dependent Isothermal Transformation Diagram Reveals Fibrous Amyloid and Non-Fibrous, Amorphous Aggregate Species

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Open journal of Biophysics 2014年第2期4卷 39-50页

作者： Lisa C. burnett Benjamin j. burnett Bin Li Samuel T. Durrance Shaohua Xu Department of Biological Sciences Florida Institute of Technology Melbourne Florida USA Department of Chemical Engineering Florida Institute of Technology Melbourne Florida USA Space Life Sciences Laboratory Kennedy Space Center Titusville Florida USA Department of Biological Sciences Florida Institute of Technology Melbourne Florida USA Space Life Sciences Laboratory Kennedy Space Center Titusville Florida USA Department of Physics and Space Sciences Florida Institute of Technology Melbourne Florida USA Space Life Sciences Laboratory Kennedy Space Center Titusville Florida USA Department of Physics and Space Sciences Florida Institute of Technology Melbourne Florida USA

Deposition of aggregated protein is associated with many human diseases. The mechanism by which protein aggregate species cause cellular death remains unclear. A profile revealing protein aggregation products under a diverse set of conditions allows the search of novel aggregate products and potential pathogens. To achieve this end, an isothermal transformation diagram (ITD) of lysozyme aggregation was constructed. AFM, TEM, and Thioflavin T binding assays were used to analyze the aggregate species synthesized under a broad range of pH values, protein concentrations, and incubation times. Four states were found: 1) soluble protein species;2) insoluble amyloid fibers;3) insoluble amorphous aggregates;and 4) protein hydrogels. The hydrogel-a rises from aggregated amyloid fibers. This work is part of an effort to construct an array of ITDs reporting aggregation properties of many disease relevant proteins, including amyloid beta, tau, α-synuclein, and others involved in protein aggregation diseases. In addition, we propose hydrogel cyto toxicity as a potential novel mechanism in the pathogenesis of amyloid diseases.

关键词： Phase Diagram Alzheimer’s Disease Prion Dementia Protein Aggregation Self-Assembly Hydrogel Gel Amorphous Aggregate

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大型办公楼配电系统的谐波评估与抑制

上海交通大学学报 1999年第12期33卷 1570-1574页

作者：傅正财杜亚平 j.burnett 上海交通大学电力学院上海200030 香港理工大学屋宇设备工程学系

为评估大型办公楼配电系统的谐波水平，寻求抑制谐波的方法，对该系统的特点进行了分析．应用公用电网谐波国家标准，确定了两层公共连接点（ＰＣＣ）上的谐波限值．在香港的１４座办公楼中对各ＰＣＣ的谐波水平进行了评估．发现有些... 详细信息

为评估大型办公楼配电系统的谐波水平，寻求抑制谐波的方法，对该系统的特点进行了分析．应用公用电网谐波国家标准，确定了两层公共连接点（ＰＣＣ）上的谐波限值．在香港的１４座办公楼中对各ＰＣＣ的谐波水平进行了评估．发现有些情况下电压和电流的谐波畸变水平都超出了限定值，租户供电电路的谐波畸变尤其严重，有些直立干线上的电压总谐波畸变率甚至超过１５％．对照明、小功率用电和空调电路等分支电路中的谐波情况也进行了调查，总结了其谐波特点．基于对谐波评估结果的分析，提出了控制谐波源，减小直立干线阻抗，均衡布置非线性负荷，利用谐波的集合效应等谐波抑制措施．

关键词：电力系统高层建筑物谐波测量配电系统办公楼