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Control Theory and Technology 2021年第1期19卷 127-141页

作者： Jeisson E.Otero-Leal john Cortes-Romero Efredy Delgado Aguilera Felipe Galarza-Jimenez alexander Jimenez-Triana Departamento de Eléctricay Electrónica Facultad de IngeníeraUniversidad Nacional de ColombiaBogotáD.C..Colombia Department of Control Engineering Universidad Distrital Francisco Joséde CaldasBogotáColombia

An adaptation of the active disturbance rejection control(AD RC)approach is applied to a fractional-order system with a flat *** the rather scarce information about the system,the conditions to establish an ultimate bound for a specific configuration of the system are found and compiled in a guideline for the tuning of the observer implemented in the ADRC.

关键词： ADRC Fractional-order system Ultimate bound Final value theorem

Functionalized, carbon nanotube material for the catalytic degradation of organophosphate nerve agents

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Nano Research 2014年第3期7卷 390-398页

作者： Mark M. Bailey john M. Heddleston jeffrey Davis Jessica L. Staymates Angela R. Hight Walker National Institute of Standards and Technology (NIST) Semiconductor and Dimensional Metrology Division Gaithersburg MD USA National Institute of Standards and Technology (NIST) Materials Measurement Science Division Gaithersburg MD USA Present Address: United States Army Medical Research Institute of Infectious Diseases (USAMRIID) Center for Aerobiological Sciences Fort Detrick MD USA

Recent world events have emphasized the need to develop innovative, functional materials that will safely neutralize chemical warfare （CW） agents in situ to protect military personnel and civilians from dermal exposure. Here, we demonstrate the efficacy of a novel, proof-of-concept design for a Cu-containing catalyst, chemically bonded to a single-wall carbon nanotube （SWCNT） structural support, to effectively degrade an organophosphate simulant. SWCNTs have high tensile strength and are flexible and light-weight, which make them a desirable structural component for unique, fabric-like materials. This study aims to develop a self-decontaminating, carbon nanotube-derived material that can ultimately be incorporated into a wearable fabric or protective material to minimize dermal exposure to organophosphate nerve agents and to prevent accidental exposure during decontamination procedures. Carboxylated SWCNTs were functionalized with a polymer, which contained Cu-chelating bipyridine groups, and their catalytic activity against an organophosphate simulant was measured over time. The catalytically active, functionalized nanomaterial was characterized using X-ray fluorescence and Raman spectroscopy. Assuming zeroth-order reaction kinetics, the hydrolysis rate of the organophosphate simulant, as monitored by UV-vis absorption in the presence of the catalytically active nanomaterial, was 63 times faster than the uncatalyzed hydrolysis rate for a sample containing only carboxylated SWCNTs or a control sample containing no added nanotube materials.

关键词： single-wall carbonnanotubefunctionalization catalytically-activenanomaterial chemical warfare agent

China＇s Rise： Challenging the Binary Discourse of American Civil Society

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Fudan Journal of the Humanities and Social Sciences 2011年第3期4卷 108-114页

作者： jeffrey C. alexander Hans Andersson

For the US, China＇s rise presents an extraordinary challenge. Many called the twentieth century the ＂ American Century,＂ just as the nineteenth was the ＂British Century. ＂ Yet the United Nations found in 2007 that no fewer than a dozen countries have in our twenty-first century advanced beyond the United States in overall development per capita. This feat the People＇s Republic of China has not yet accomplished, and whether it ever will remain to be seen.

关键词：中国人美国话语二元社会民间联合国共和国

Radiological determination of the cranial index of present-day Ghanaians

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Forensic Sciences Research 2022年第2期7卷 138-141页

作者： Benard Ohene Botwe jeffrey Nana Afari Boadu Kofi Adesi Kyei john D.Thompson Department of Radiography University of Ghana School of Biomedical&Allied Health SciencesCollege of Health SciencesAccraGhana Directorate of Radiography School of Health SciencesUniversity of SalfordSalfordUK

The cranial index(CI)of Ghanaians is currently *** aim of this study was to measure the CI in a population of Ghanaians in order to classify them against pre-determined CI categories.A systematic random sampling method was used to select 300 normal computed tomography(CT)head scans of adult Ghanaians from the largest hospital in *** patients were deemed to have a normal cranial image configuration based on the radiological *** biparietal diameter(BPD,width)and the occipitofrontal diameter(OFD,length)were measured on transaxial CT images using a workstation with a calibrated measurement calliper *** CI ratio was calculated as the BPD multiplied by 100 and divided by the ***,standard deviation(SD)and range were calculated for BPD,OFD and *** in measurements between demographic groups were compared using an unpaired t-test,with testαset at *** the population of Ghanaians included in this study,165(55%)were male and 135(45%)were *** mean CI was 77.3±3.6 in males and 79.0±3.3 in females,placing both genders in the mesocephalic ***,the difference between males and females was found to be statistically significant(P=0.02).The study indicated that most Ghanaian adults belong to the mesocephalic category of *** also had a higher CI,which could be used to differentiate gender *** information can be useful for forensic medicine,plastic surgeries for clinical and research purpose.

关键词： Forensic sciences cranial index CI sexual dimorphism computed tomography CT

Metabolomic Profiling in Selaginella lepidophylla at Various Hydration States Provides New Insights into the Mechanistic Basis of Desiccation Tolerance

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Molecular Plant 2013年第2期6卷 369-385页

作者： Abou Yobi Bernard W.M. Wone Wenxin Xu Danny C. alexander Lining Guo john A. Ryals Melvin J. Oliver john C. Cushman Department of Biochemistry and Molecular Biology University of Nevada Reno NV 89557-0330 USA Department of Biological Sciences University of Nevada Reno NV 89557-0314 USA Metabolon Inc. 800 Capitola Drive Suite 1 Durham NC 27713 USA US Department of Agriculture-Agricultural Research Service Plant Genetic Research Unit University of Missouri Columbia MI 65211 USA

Selaginella lepidophylla is one of only a few species of spike mosses （Selaginellaceae） that have evolved des-iccation tolerance （DT） or the ability to ＇resurrect＇ from an air-dried state. In order to understand the metabolic basis of DT, S, lepidophylla was subjected to a five-stage, rehydration/dehydration cycle, then analyzed using non-biased, global metabolomics profiling technology based on GC/MS and UHLC/MS/MS2 platforms. A total of 251 metabolites including 167 named （66.5%） and 84 （33.4%） unnamed compounds were characterized. Only 42 （16.7%） and 74 （29.5%） of compounds showed significantly increased or decreased abundance, respectively, indicating that most compounds were produced con-stitutively, including highly abundant trehalose, sucrose, and glucose. Several glycolysis/gluconeogenesis and tricarboxylic acid （TCA） cycle intermediates showed increased abundance at 100% relative water content （RWC） and 50% RWC. Vanillate, a potent antioxidant, was also more abundant in the hydrated state. Many different sugar alcohols and sugar acids were more abundant in the hydrated state. These polyols likely decelerate the rate of water loss during the drying process as well as slow water absorption during rehydration, stabilize proteins, and scavenge reactive oxygen species （ROS）. In contrast, nitrogen-rich and y-glutamyl amino acids, citrulline, and nucleotide catabolism products （e.g. allantoin） were more abundant in the dry states, suggesting that these compounds might play important roles in nitrogen remobilization during rehydration or in ROS scavenging. UV-protective compounds such as 3-（3-hydroxyphenyl）propionate, apigenin, and naringenin, were more abundant in the dry states. Most lipids were produced constitutively, with the exception of choline phosphate, which was more abundant in dry states and likely plays a role in membrane hydration and stabilization. In contrast, several poly- unsaturated fatty acids were more abundant in the hydrated states, suggestin

关键词： abiotic/environmental stress mass spectrometry metabolomics oxidative/photooxidative stress desiccationtolerance Selaginella.

An Algorithm for Practical Power Curve Estimation of Wind Turbines

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CSEE Journal of Power and Energy Systems 2018年第1期4卷 93-102页

作者： Milad Javadi alexander M.Malyscheff Di Wu Chongqing Kang john N.Jiang School of Electrical and Computer Engineering University of OklahomaNormanOklahoma 73019USA e Electrical Engineering Department Tsinghua UniversityBeijing 100084China

Practical power curve estimation is necessary for evaluating the actual power output of a wind farm;since a power curve provided by the wind turbine manufacture will be different with the actual power curve following several years of *** can be estimated using the collected power output data including wind power generation and wind *** data is commonly ill-distributed due to a noticeable number of outliers,which impose a serious bias to the estimation models obtained from this *** introduces an interesting challenge in estimation of a power *** this paper,an intelligent algorithm is proposed for estimating a power curve using the measured data while modeling and bias errors,imposed to the estimation model by the outliners,are *** specifically,this algorithm is designed based on the Statistical Analysis Software(SAS)programming software package in order to facilitate analyzing and managing big datasets of wind speed and wind power *** effectiveness and practical application of the proposed algorithm is demonstrated using a real-world dataset.

关键词： Data processing predictive models wind energy wind energy integration wind farms wind power curve

Improved Hepascore in hepatitis C predicts reversal in risk of adverse outcome

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World Journal of Hepatology 2017年第19期9卷 850-856页

作者： Angus W jeffrey Yi Huang W Bastiaan de Boer Leon A Adams Gerry MacQuillan David Speers john Joseph Gary P jeffrey School of Medicine University of Notre Dame School of Medicine and Pharmacology University of Western Australia Department of Hepatology Sir Charles Gairdner Hospital Department of Anatomical Pathology Path West QEII Medical Centre Department of Microbiology Path West QEII Medical Centre Department of Biochemistry Path West QEII Medical Centre

AIM To establish if serial Hepascore tests(referred to as delta Hepascore) in those with chronic hepatitis C(CHC) correlate with the increase and/or decrease in risk of liver related *** Three hundred and forty-six CHC patients who had two Hepascore tests performed were studied. During 1944 patient years follow-up 28(8.1%) reached an endpoint. The Hepascore is a serum test that provides clinically useful data regarding the stage of liver fibrosis andsubsequent clinical outcomes in chronic liver *** Patients with a baseline Hepascore > 0.75 had a significantly increased rate of reaching a composite endpoint consisting of hepatocellular carcinoma, liver death, and/or decompensation(P 0.75, a subsequent improved Hepascore showed a significantly decreased risk for the composite endpoint(P = 0.004). There were no negative outcomes in those with a stable or improved delta Hepascore. The minimum time between tests that was found to give a statically significant result was in those greater than one year(P = 0.03).CONCLUSION In conclusion, Hepascore is an accurate predictor of liver related mortality and liver related morbidity in CHC patients. Of note, we have found that there is a decreased risk of mortality and morbidity in CHC patients when the patient has an improving delta Hepascore. Repeat Hepascore tests, when performed at a minimum one-year interval, may be of value in routine clinical practice to predict liver related clinical outcomes and to guide patient management.

关键词： Chronic Prognosis Direct acting antivirals Serum Hepatitis C

Ultra-high speed holographic shape and displacement measurements in the hearing sciences

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Light(Advanced Manufacturing) 2022年第2期3卷 1-14页

作者： Haimi Tang Pavel Psota john J.Rosowski Cosme Furlong jeffrey Tao Cheng Center for Holographic Studies and Laser micro-mechaTronics Worcester Polytechnic InstituteWorcesterMA USA01609 Mechanical Engineering Department Worcester Polytechnic InstituteWorcesterMA USA01609 Faculty of Mechatronics Informatics and Interdisciplinary StudiesTechnical University of LiberecLiberecCzech Republic46117 Eaton-Peabody Laboratory Massachusetts Eye and EarBostonMA USA02114 Department of Otolaryngology-Head and Neck Surgery Harvard Medical SchoolBostonMAUSA02115

The auditory system of mammals enables the perception of sound from our surrounding *** some of the smallest bones in the body,the ear transduces complex acoustic signals with high-temporal sensitivity to complex mechanical vibrations with magnitudes as small as tens of *** of the shape and acoustically induced motions of different components of the ear are essential if we are to expand our understanding of hearing mechanisms,and also provide quantitative information for the development of numerical ear models that can be used to improve hearing protection,clinical diagnosis,and repair of damaged or diseased *** are developing digital holographic methods and instrumentation using an ultra-high speed camera to measure shape and acoustically-induced motions in the middle *** we study the eardrum,the first structure of the middle ear which initializes the acoustic-mechanical transduction of sound for *** measurement system is capable of performing holographic measurement at rates up to 2.1 M frames per *** shape measurement modalities had previously been implemented into our holographic systems:(1)a multi-wavelength method with a wavelength tunable laser;and(2)a multi-angle illumination method with a single wavelength *** this paper,we present a third method using a miniaturized fringe projection system with a microelectromechanical system(MEMS)***,we optimize the processing of large data sets of holographic displacement measurements using a vectorized Pearson's correlation *** validate and compare the shape and displacement measurements of our methodologies using a National Institute of Standards and Technology(NIST)traceable gauge and sound-activated latex membranes and human eardrums.

关键词： Ultra-high speed digital holography Microelectromechanical systems(MEMS) Miniaturized Fringe Projection Middle-ear mechanics Shape and displacement measurements.

A microfluidic platform for cultivating ovarian cancer spheroids and testing their responses to chemotherapies

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Microsystems & Nanoengineering 2020年第1期6卷 315-326页

作者： Neda Dadgar Alan M.Gonzalez-Suarez Pouria Fattahi Xiaonan Hou john S.Weroha Alexandre Gaspar-Maia Gulnaz Stybayeva alexander Revzin Department of Physiology and Biomedical Engineering Mayo ClinicRochesterMN 55905USA Department of Medical Oncology Mayo ClinicRochesterMN 55905USA Department of Laboratory Medicine and Pathology Mayo ClinicRochesterMN 55905USA

There is increasing interest in utilizing in vitro cultures as patient avatars to develop personalized treatment for *** cultures utilize Matrigel-coated plates and media to promote the proliferation of cancer cells as spheroids or tumor ***,standard culture conditions operate in large volumes and require a high concentration of cancer cells to initiate this *** limitations include variability in the ability to successfully establish a stable line and inconsistency in the dimensions of these microcancers for in vivo drug response *** paper explored the utility of microfluidics in the cultivation of cancer cell *** patient-derived xenograft(PDX)tumors of high-grade serous ovarian cancer were used as the source material to demonstrate that viability and epithelial marker expression in the microfluidic cultures was superior to that of Matrigel or large volume 3D *** further demonstrate the potential for miniaturization and multiplexing,we fabricated multichamber microfluidic devices with integrated microvalves to enable serial seeding of several chambers followed by parallel testing of several drug *** valve-enabled microfluidic devices permitted the formation of spheroids and testing of seven drug concentrations with as few as 100,000 cancer cells per ***,we demonstrate the feasibility of maintaining difficul-to-culture primary cancer cells and testing drugs in a microfluidic *** microfluidic platform may be ideal for drug testing and personalized therapy when tumor material is limited,such as following the acquisition of biopsy specimens obtained by fine-needle aspiration.

关键词： testing fluid cancer

Gastric per-oral endoscopic myotomy: Current status and future directions

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World Journal of Gastroenterology 2019年第21期25卷 2581-2590页

作者： alexander Podboy Joo Ha Hwang Linda A Nguyen Patricia Garcia Thomas A Zikos Afrin Kamal George Triadafilopoulos john O Clarke Division of Gastroenterology and Hepatology Stanford University School of Medicine

Gastroparesis, or symptomatic delayed gastric emptying in the absence of mechanical obstruction, is a challenging and increasingly identified syndrome. Medical options are limited and the only medication approved by the Food and Drug Administration for treatment of gastroparesis is metoclopramide, although other agents are frequently used off label. With this caveat, first-line treatments for gastroparesis include dietary modifications, antiemetics and promotility agents, although these therapies are limited by suboptimal efficacy and significant medication side effects. Treatment of patients that fail first-line treatments represents a significant therapeutic challenge. Recent advances in endoscopic techniques have led to the development of a promising novel endoscopic therapy for gastroparesis via endoscopic pyloromyotomy, also referred to as gastric per-oral endoscopic myotomy or per-oral endoscopic pyloromyotomy. The aim of this article is to review the technical aspects of the per-oral endoscopic myotomy procedure for the treatment of gastroparesis, provide an overview of the currently published literature, and outline potential next directions for the field.

关键词： Gastroparesis Gastric per-oral endoscopic myotomy Per-oral endoscopic pyloromyotomy Myotomy Endoscopic myotomy Peroral endoscopic myotomy Gastric emptying