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Frequency dependent polarization analysis of ambient seismic noise recorded at a broadband seismometer in the central United States

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Earthquake Science 2010年第5期23卷 439-447页

作者： keith d. Koper Veronica L. Hawley department of Geology and Geophysics University of Utah department of Earth and Atmospheric Sciences Saint Louis University

We present a new approach to polarization analysis of seismic noise recorded by three-component seismometers. It is based on statistical analysis of frequency-dependent particle motion properties determined from a large number of time windows via eigenanalysis of the 3-by-3, Hermitian, spectral covariance matrix. We applied the algorithm to continuous data recorded in 2009 by the seismic station SLM, located in central North America. A rich variety of noise sources was observed. At low frequencies （〈0.05 Hz） we observed a tilt-related signal that showed some elliptical motion in the horizontal plane. In the microseism band of 0.05-0.25 Hz, we observed Rayleigh energy arriving from the northeast, but with three distinct peaks instead of the classic single and double frequency peaks. At intermediate frequencies of 0.5-2.0 Hz, the noise was dominated by non-fundamental-mode Rayleigh energy, most likely P and Lg waves. At the highest frequencies （〉3 Hz）, Rayleigh-type energy was again dominant in the form of Rg waves created by nearby cultural activities. Analysis of the time dependence of noise power shows that a frequency range of at least 0.02-1.0 Hz （much larger than the microseism band） is sensitive to annual, meteorologically induced sources of noise.

关键词： seismic noise polarization analysis central North America

NAFLd fibrosis score:A prognostic predictor for mortality and liver complications among NAFLd patients

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World Journal of Gastroenterology 2013年第8期19卷 1219-1229页

作者： Sombat Treeprasertsuk Einar Bjrnsson Felicity Enders Sompongse Suwanwalaikorn keith d Lindor department of Medicine Faculty of MedicineChulalongkorn UniversityBangkok 10330Thailand department of Internal Medicine Section of Gastroenterology and Hepatologythe National University Hospital of IcelandIS121 ReykjavikIceland Biostatistics and Health Sciences Research Mayo ClinicRochesterMN 55902United States Health Solutions Arizona State UniversityTempeAZ 85004United States

AIM:To study whether the severity of liver fibrosis estimated by the nonalcoholic fatty liver disease(NAFLd) fibrosis score can predict all-cause mortality,cardiac complications,and/or liver complications of patients with NAFLd over long-term ***:A cohort of well-characterized patients with NAFLd diagnosed during the period of 1980-2000 was identified through the Rochester Epidemiology *** NAFLd fibrosis score(NFS) was used to separate NAFLd patients with and without advanced liver *** used the NFS score to classify the probability of fibrosis as -1.5 to diate probability,and > 0.67 for high *** endpoints included allcause death and cardiovascular-and/or liver-related *** the 479 patients with NAFLd assessed,302 patients(63%) greater than 18 years old were *** patients were followed,and medical charts were reviewed until August 31,2009 or the date when the first primary endpoint *** using a standardized case record form,we recorded a detailed history and physical examination and the use of statins and metformin during the follow-up ***:A total of 302/479(63%) NAFLd patients(mean age:47 ± 13 year) were included with a followup period of 12.0 ± 3.9 year.A low probability of advanced fibrosis(NFS d in 181 patients(60%),while an intermediate or high probability of advanced fibrosis(NSF >-1.5) was found in 121 patients(40%).At the end of the follow-up period,55 patients(18%) developed primary endpoints.A total of 39 patients(13%) died during the *** leading causes of death were non-hepatic malignancy(n = 13/39;33.3%),coronary heart disease(CHd)(n = 8/39;20.5%),and liver-related mortality(n = 5/39;12.8%).Thirty patients had new-onset CHd,whereas 8 of 30 patients(27%) died from CHd-related causes during the *** a multivariate analysis,a higher NFS at baseline and the presence of new-onset CHd were si

关键词： Nonalcoholic fatty liver disease fibrosis score Prognostic predictor Mortality Liver complications

Molecular mechanisms of viral hepatitis induced hepatocellular carcinoma

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World Journal of Gastroenterology 2020年第38期26卷 5759-5783页

作者： Simmone d'souza keith CK Lau Carla S Coffin Trushar R Patel department of Microbiology Immunologyand Infectious DiseasesCumming School of MedicineUniversity of CalgaryCalgary T2N 1N4ABCanada department of Chemistry and Biochemistry Alberta RNA Research and Training InstituteUniversity of LethbridgeLethbridge T1K3M4ABCanada

Chronic infection with viral hepatitis affects half a billion individuals worldwide and can lead to cirrhosis,cancer,and liver *** cancer is the third leading cause of cancer-associated mortality,of which hepatocellular carcinoma(HCC)represents 90%of all primary liver *** tumors like HCC are complex and have heterogeneous tumor genomic profiles contributing to complexity in diagnosis and *** infection with hepatitis B virus(HBV),hepatitis delta virus(HdV),and hepatitis C virus(HCV)are the greatest etiological risk factors for *** to the significant role of chronic viral infection in HCC development,it is important to investigate direct(viral associated)and indirect(immune-associated)mechanisms involved in the pathogenesis of *** mechanisms used by HBV,HCV,and HdV that drive hepatocarcinogenesis include persistent liver inflammation with an impaired antiviral immune response,immune and viral protein-mediated oxidative stress,and deregulation of cellular signaling pathways by viral *** integration to promote genome instability is a feature of HBV infection,and metabolic reprogramming leading to steatosis is driven by HCV *** current review aims to provide a brief overview of HBV,HCV and HdV molecular biology,and highlight specific viral-associated oncogenic mechanisms and common molecular pathways deregulated in HCC,and current as well as emerging treatments for HCC.

关键词： Chronic viral infection Hallmarks of cancer Hepatocellular carcinoma Hepatitis B virus Hepatitis C virus Hepatitis delta virus co-infection Molecular mechanisms Viral hepatitis

PHOTOVOLTAIC HYdROGEN PROdUCTION PROTOTYPE:SUSTAINABLE ENERGY FOR RESIdENCES

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Journal of Green Building 2008年第3期3卷 133-141页

作者： d.keith Roper Edward Trujillo Rachel Bradshaw department of Chemical Engineering University of UtahSalt Lake CityUT 84112 不详

Residential use of hydrogen(H_(2)),for utility or personal transportation,is currently limited by economic effectiveness,lack of residential sources,and need for engineering improvements.A modular photovoltaic hydrogen production prototype(PHPP)was constructed to produce three liters of hydrogen per day at standard temperature and pressure with maximum energy and Faraday efficiencies of 75%and 89%,*** 3 liters of H_(2)with the PHPP required 2.4 milliliters of distilled H_(2)O and 26 kJ of solar energy and eliminated 1.5 liters of byproduct CO_(2)relative to steam reforming of methane to generate H_(2).A capital investment of$5,651 to produce 30 liters per day using additional PHPP modules gave a return on investment of 4.2%and a payback period of 7.5 *** teams of university and high school students constructed the PHPP and were familiarized with key aspects of sustainable use of hydrogen as an energy *** and geographical barriers to effective communication and teamwork among the students were met by organizing teams to meet student needs,providing instruction and hands-on training in teamwork and facilitating web-based and in-class *** ethnographic observation of student interactions showed involving students in lectures and extracurricular presentations and enhancing communication and teamwork with constructive responses to student feedback increased student satisfaction with the experience.

关键词： photovoltaic hydrogen electrolysis Photovoltaic Hydrogen Production Prototype(PHPP)

Strategic Analysis of a Regulatory Conflict Using dempster-Shafer Theory and AHP for Preference Elicitation

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Journal of Systems Science and Systems Engineering 2019年第4期28卷 415-433页

作者： Maisa M. Silva keith W. Hipel d. Marc Kilgour Ana Paula C. S. Costa department of Management Engineerin& Universidade Federal de Pernambuco Recife Brazil department of Systems design Engineering University of Waterloo Waterloo Canada department of Mathematics Wilfrid Laurier UniversityWaterloo Canada

dempster-Shafer Theory (dST) and the Analytic Hierarchy Process (AHP) are integrated in order to elicit preference information from experts regarding decision makers (dMs) involved in a regulatory conflict. More precisely, dST is used for combining expert knowledge regarding preferences of a specific dM (the regulatory body), and AHP is employed for ranking feasible states in the conflict for this same dM. In order to illustrate how this preference elicitation proposal can be conveniently implemented in practice within the Graph Model for Conflict Resolution (GMCR), it is applied to a real construction dispute located in the city of Ipojuca, Brazil. The conflict is modeled with three dMs: support, opposition, and the regulatory body. Results show that the new preference methodology possesses many inherent advantages including high flexibility the ability to capture uncertainty or even ignorance about preferences, the possibility of combining expert knowledge with respect to missing preferences, and a substantial reduction in the number of pairwise comparisons of states required to express preference information.

关键词： Regulatory conflict graph model for conflict resolution absence of preference information dST-AHP

Separations of Metal Ions Using Ionic Liquids: The Challenges of Multiple Mechanisms

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Tsinghua Science and Technology 2006年第2期11卷 188-193页

作者： Violina A. Cocalia John d. Holbrey keith E. Gutowski Nicholas J. Bridges Robin d. Rogers department of Chemistry and Center for Green Manufacturing The University of Alabama Tuscaloosa AL 35487 USA

Ionic liquids are a distinct sub-set of liquids, comprising only of cations and anions, often with negligible vapor pressure. As a result of the low or non-volatility of these fluids, ionic liquids are often considered in liquid/liquid separation schemes where the goal is to replace volatile organic solvents. Unfortunately, it is often not yet recognized that the ionic nature of these solvents can result in a variety of extraction mechanisms, including solvent ion-pair extraction, ion exchange, and simultaneous combinations of these. This paper discusses current ionic liquid-based separations research where the effects of the nature of the solvent ions, ligands, and metal ion species were studied in order to be able to understand the nature of the challenges in utilizing ionic liquids for practical applications.

关键词： metal ion liquid-liquid separation ionic liquid solvent extraction

Clinical features and management of primary sclerosing cholangitis

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World Journal of Gastroenterology 2008年第21期14卷 3338-3349页

作者： Marina G Silveira keith d Lindor division of Gastro-enterology and Hepatology Miles and Shirley Fiterman Center for Digestive DiseasesMayo Clinic and FoundationRochesterMinnesotaUnited States

Primary sclerosing cholangitis is a chronic cholestatic liver disease characterized by inflammation and fibrosis of the bile ducts,resulting in cirrhosis and need for liver transplantation and reduced life *** majority of cases occur in young and middle-aged men,often in association with inflammatory bowel *** etiology of primary sclerosing cholangitis includes immune-mediated components and elements of undefined *** effective medical therapy has been *** multiple complications of primary sclerosing cholangitis include metabolic bone disease,dominant strictures,bacterial cholangitis,and malignancy,particularly cholangiocarcinoma,which is the most lethal complication of primary sclerosing *** transplantation is currently the only life-extending therapeutic alternative for patients with end-stage disease,although recurrence in the allografted liver has been described.A PSC-like variant attracting attention is cholangitis marked by raised levels of the immunoglobulin G4 subclass,prominence of plasma cells within the lesions,and steroid responsiveness.

关键词： Sclerosing cholangitis diagnosis Therapy Cholestasis Cholangiocarcinoma Liver transplantation

MR-GUIdEd PULSE OXIMETRY IMAGING OF BREAST IN VIVO

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Journal of Innovative Optical Health Sciences 2011年第2期4卷 199-208页

作者： ZHIQIU LI SHUdONG JIANG VENKATARAMANAN KRISHNASWAMY SCOTT CdAVIS SUBHAdRA SRINIVASAN keith d.PAULSEN BRIAN W.POGUE Thayer School of Engineering Dartmouth College Hanover NH 03755USA

A near-infrared(NIR)tomography system with spectrally-encoded sources in two wavelength bands was built to quantify the temporal oxyhemoglobin and deoxyhemoglobin contrast in breast tissue at a 20 Hz *** system was integrated into a 3T magnetic resonance(MR)imaging system through a customized breast coil interface for simultaneous optical and MRI *** this configuration,the MR images provide breast tissue structural information for NIR spectroscopy of adipose andfibro-glandular tissue in *** characterization performance of the NIR system was verified through dynamic phantom *** human subjects were imaged withfinger pulse oximeter(PO)plethysmogram synchronized to the NIR system to provide a frequency-locked *** the raw data from the NIR system and the recovered absorption coefficients of the breast at two wavelengths showed the same frequency of about 1.3 Hz as the PO *** frequency lock-in approach provided a practical platform for MR-localized recovery of small pulsatile variations of oxyhemoglobin and deoxyhemoglobin in the breast,which are related to the heartbeat and vascular resistance of the tissue.

关键词： High frame-rate fast imaging MR-guided near-infrared tomography breast hemodynamics

Ipsilateral femur and tibia fractures in pediatric patients:A systematic review

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World Journal of Orthopedics 2017年第8期8卷 638-643页

作者： Jason B Anari Alexander L Neuwirth B david Horn keith d Baldwin department of Orthopaedic Surgery University of Pennsylvania Children’s Hospital of Philadelphia

AIM To better understand how pediatric floating knee injuries are managed after the wide spread use of new orthopaedic *** We searched EMBASE, COCHRANE and MEdLINE computerized literature databases from the earliest date available in the databases to February 2017 using the following search term including variants and pleural counterparts: Pediatric floating knee. All studies were thoroughly reviewed by multiple authors. Reference lists from all articles were scrutinized to identify any additional studies of interest. A final database of individual patients was assembled from the literature. Univariate and multivariate statistical tests were applied to the assembled database to assess differences in *** The English language literature contains series with a total of 97 pediatric patients who sustained floating knee injuries. Patients averaged 9.3 years of age and were mostly male(73). Approximately 25% of the fractures were open injuries, more tibia(27) than femur(10). Over 75% of the fractures of both the tibia and the femur involved the diaphysis. More than half(52) of the patients were treated non-operatively for both fractures. As a sequela of the injury 32(33%) patients were left with a limb length discrepancy, 24(25%) patients had lengthening of the injured limb at follow up, while 8(8%) had shortening of the affected limb. Infection developed in 9 patients and 3 had premature physeal closure. Younger patients were more likely to be treated non-operatively(P d patients treated with operative intervention had statistically significant shorter hospital length of stays(P = 0.001).CONCLUSION Given the predominance of non-operative managementin published studies, the available literature is not clinically relevant since the popularization of internal fixation for pediatric long-bone

关键词： Pediatrics Femur Tibia Fracture Floating knee