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  1. Thesis ; Online: Investigation of a Contact Resonance Atomic Force Microscopy Scan Speed Phenomenon

    Glover, Christopher Cash

    2018  

    Abstract: There are many unexplained phenomena that have been observed via atomic force microscopy (AFM) experiments. Understanding the cause of these phenomena is important to perform more accurate quantitative imaging using contact-resonance AFM and other ... ...

    Abstract There are many unexplained phenomena that have been observed via atomic force microscopy (AFM) experiments. Understanding the cause of these phenomena is important to perform more accurate quantitative imaging using contact-resonance AFM and other contact-mode AFM techniques at higher scan speeds. This thesis presents evidence to confirm the existence of a scan speed dependent contact-mode AFM phenomenon and applies a squeeze film hydrodynamic lubrication model to explain it. Contact-resonance spectroscopy is used to investigate the phenomenon in which, above a critical scan speed, there is a monotonic decrease in the measured contact-resonance frequency with increasing scan speed. The observed phenomenon was replicated on a mica sample in a randomized set of AFM experiments performed at the National Institute for Standards and Technology (NIST). A literature review revealed that there is a thin water film that exists on mica under certain relative humidity (RH) conditions that has dynamic properties. The squeeze film hydrodynamic lubrication model predicts the general trend observed in the experimental data. However, there exists a higher order model that can be used to investigate the scan speed phenomenon more completely.
    Keywords Mechanical engineering|Nanoscience
    Subject code 621
    Language ENG
    Publishing date 2018-01-01 00:00:01.0
    Publisher University of Nevada, Reno
    Publishing country us
    Document type Thesis ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  2. Article ; Online: Assessing shared respiratory pathogens between domestic (Ovis aries) and bighorn (Ovis canadensis) sheep; methods for multiplex PCR, amplicon sequencing, and bioinformatics to characterize respiratory flora.

    Fox, Karen A / MacGlover, Christopher A W / Blecha, Kevin A / Stenglein, Mark D

    PloS one

    2023  Volume 18, Issue 10, Page(s) e0293062

    Abstract: Respiratory disease is responsible for dramatic population declines in bighorn sheep (Ovis canadensis), and respiratory pathogen diagnostics contribute to the management of bighorn populations. To create a comprehensive and consistent approach to bighorn ...

    Abstract Respiratory disease is responsible for dramatic population declines in bighorn sheep (Ovis canadensis), and respiratory pathogen diagnostics contribute to the management of bighorn populations. To create a comprehensive and consistent approach to bighorn sheep respiratory diagnostics, we created a culture-independent assay to detect and strain type Mannheimia haemolytica, Bibersteinia trehalosi, Pasteurella multocida, and Mycoplasma ovipneumoniae. The assay also detects and characterizes the Pasteurellaceae leukotoxin A gene, and broadly assesses the bacterial composition of each sample based on 16S rRNA sequences. The assay is based on a three-step approach: 1) Multiplex PCR to amplify targets including eight loci for each bacterial species, the Pasteurellaceae lktA gene, and the 16S rRNA gene 2) Library preparation, barcoding, and short-read Illumina sequencing to determine the genetic sequences of each target, and 3) Bioinformatics in the form of automated software to analyze genetic sequences. The assay was designed to assess shared pathogens between domestic and bighorn sheep, but could be useful for many applications in bighorn sheep respiratory disease research and management.
    MeSH term(s) Animals ; Sheep ; Sheep, Bighorn/genetics ; Sheep, Bighorn/microbiology ; Sheep, Domestic ; Multiplex Polymerase Chain Reaction ; RNA, Ribosomal, 16S/genetics ; Sheep Diseases/epidemiology ; Mannheimia haemolytica/genetics ; Respiratory Tract Diseases ; Computational Biology
    Chemical Substances RNA, Ribosomal, 16S
    Language English
    Publishing date 2023-10-19
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2267670-3
    ISSN 1932-6203 ; 1932-6203
    ISSN (online) 1932-6203
    ISSN 1932-6203
    DOI 10.1371/journal.pone.0293062
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Coronary Artery Disease in patients with End-Stage Kidney Disease; Current perspective and gaps of knowledge.

    Levi, Amos / Simard, Trevor / Glover, Christopher

    Seminars in dialysis

    2020  Volume 33, Issue 3, Page(s) 187–197

    Abstract: Coronary artery disease (CAD) is very common in dialysis patients. One third have preexisting CAD and another one third have significant occult disease at the time of starting dialysis. Symptoms are often absent or are atypical, emphasizing the need for ... ...

    Abstract Coronary artery disease (CAD) is very common in dialysis patients. One third have preexisting CAD and another one third have significant occult disease at the time of starting dialysis. Symptoms are often absent or are atypical, emphasizing the need for vigorous screening, specifically in patients awaiting transplant. The lesions tend to be heavily calcified, diffuse, and involve multiple vessels, consequently, percutaneous coronary interventions are more complicated to perform, and are less successful in achieving and maintaining short- and long-term patency. Dialysis patients have been excluded from the randomized controlled trials on which the current standards for managing CAD have been established. Due to differences in pathobiology and risks and benefits, it is uncertain that the results of these clinical trials extrapolate to patients with advanced chronic kidney disease (CKD). Here we review the data from observational studies and identify special considerations concerning the diagnosis and management of CAD in dialysis patients, including the use of noninvasive functional testing vs anatomical testing, the management of acute coronary syndromes and of stable coronary artery disease, the role for percutaneous revascularization vs coronary artery bypass grafting, and of platelet inhibitor therapy after coronary stenting. We review the preliminary results of the recently published ISCHEMIA-CKD trial, the only trial to date to involve large numbers of dialysis patients. This is the first of, hopefully, many trials in the pipeline that will examine therapies for CAD specifically in patients with advanced CKD, a growing population that is at particularly high risk for poor outcomes.
    MeSH term(s) Coronary Artery Disease/complications ; Coronary Artery Disease/therapy ; Humans ; Renal Dialysis ; Renal Insufficiency/complications ; Renal Insufficiency/therapy
    Language English
    Publishing date 2020-05-25
    Publishing country United States
    Document type Journal Article ; Review
    ZDB-ID 1028193-9
    ISSN 1525-139X ; 0894-0959
    ISSN (online) 1525-139X
    ISSN 0894-0959
    DOI 10.1111/sdi.12886
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Novel avibacterium species associated with sinusitis and conjunctivitis in a merriam's wild turkey (meleagris gallopavo merriami) flock in colorado, usa

    Ellis, Jayne S. / MacGlover, Christopher A. / Sondgeroth, Kerry S. / Brown, Derek / Daniels, Joshua B. / Fox, Karen A.

    The Journal of Wildlife Diseases. 2022 Nov. 30, v. 58, no. 4 p.725-734

    2022  

    Abstract: A Merriam's Wild Turkey (Meleagris gallopavo merriami) with periocular swelling and periocular skin crusting in Pueblo County, Colorado, USA, was diagnosed with severe catarrhal and fibrinous sinusitis and conjunctivitis. A novel clade of Avibacterium ... ...

    Abstract A Merriam's Wild Turkey (Meleagris gallopavo merriami) with periocular swelling and periocular skin crusting in Pueblo County, Colorado, USA, was diagnosed with severe catarrhal and fibrinous sinusitis and conjunctivitis. A novel clade of Avibacterium was detected in the exudate from this bird. Although eight additional turkeys culled from the affected flock did not have clinical signs or gross lesions, histologically all had mild-to-moderate chronic sinusitis, and infraorbital cultures yielded the same novel clade of Avibacterium that was found in the symptomatic turkey. The presence of this Avibacterium species in the absence of significant disease in some birds suggested that other factors might have been involved in the development of severe sinusitis and conjunctivitis in the symptomatic Wild Turkey. Negative culture results from a distant flock of Wild Turkeys, acquired with similar methods to the affected flock, suggested that this novel species of Avibacterium was not widespread throughout Wild Turkeys in Colorado.
    Keywords Avibacterium ; Meleagris gallopavo ; conjunctivitis ; flocks ; sinusitis ; turkeys ; wildlife ; Colorado ; Pasteurellaceae ; Wild Turkey
    Language English
    Dates of publication 2022-1130
    Size p. 725-734.
    Publishing place Wildlife Disease Association
    Document type Article ; Online
    ZDB-ID 410709-3
    ISSN 1943-3700 ; 0090-3558
    ISSN (online) 1943-3700
    ISSN 0090-3558
    DOI 10.7589/JWD-D-22-00005
    Database NAL-Catalogue (AGRICOLA)

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  5. Article ; Online: Use of Spinal Cord Stimulators in Patients With Pacemakers or Implantable Cardiac Defibrillators: A Review of Documented Accounts of Interference.

    Martens, Joshua Manuel / Fiala, Kenneth / Glover, Christopher / Zacharias, Nicholas / Abd-Elsayed, Alaa

    Neuromodulation : journal of the International Neuromodulation Society

    2021  

    Abstract: Objectives: To assess the currently available evidence regarding associations between spinal cord stimulator (SCS) lead type, clinical indications for device placement, and interference between SCSs and cardiac pacemakers (CPMs)/implantable cardioverter- ...

    Abstract Objectives: To assess the currently available evidence regarding associations between spinal cord stimulator (SCS) lead type, clinical indications for device placement, and interference between SCSs and cardiac pacemakers (CPMs)/implantable cardioverter-defibrillators (ICDs).
    Study design: Review of case reports and original research studies assessing the interference between SCS and CPM/ICD.
    Materials and methods: PubMed and Cochrane databases were searched for articles commenting on the interference between SCS and CPM/ICD. The search criteria which generated the greatest number of relevant studies was (spinal cord stimulator AND [pacemaker OR implantable cardioverter defibrillator]). Additional, empiric review was conducted using JSTOR, ScienceDirect, and EBSCOhost databases; however, no additional eligible studies were identified. Data were extracted, summarized into tables, and quantitatively analyzed using LibreTexts and MedCalc software.
    Results: There was no statistically significant interference observed between SCS and CPM/ICD devices in patients regardless of indication for SCS placement and SCS lead polarity.
    Limitations: Limited by variability of patient cases and variability in maximum frequency and amplitude of SCS devices tried in individual cases. Also limited by small sample size and the absence of a standard definition for device interference across studies.
    Conclusions: Interference between cardiac devices and SCSs is a rare occurrence. As there are currently no published guidelines, devices should be interrogated on a case-by-case basis in the SCS trial period (if implanted after cardiac device), during permanent implantation, and during scheduled follow-up visits. Peri-operative testing should include increasing the SCS settings to maximally tolerated levels with cardiac device set at its maximum sensitivity.
    Language English
    Publishing date 2021-07-29
    Publishing country United States
    Document type Journal Article ; Review
    ZDB-ID 1500372-3
    ISSN 1525-1403 ; 1094-7159
    ISSN (online) 1525-1403
    ISSN 1094-7159
    DOI 10.1111/ner.13514
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article: Scanning speed phenomenon in contact-resonance atomic force microscopy.

    Glover, Christopher C / Killgore, Jason P / Tung, Ryan C

    Beilstein journal of nanotechnology

    2018  Volume 9, Page(s) 945–952

    Abstract: This work presents data confirming the existence of a scan speed related phenomenon in contact-mode atomic force microscopy (AFM). Specifically, contact-resonance spectroscopy is used to interrogate this phenomenon. Above a critical scan speed, a ... ...

    Abstract This work presents data confirming the existence of a scan speed related phenomenon in contact-mode atomic force microscopy (AFM). Specifically, contact-resonance spectroscopy is used to interrogate this phenomenon. Above a critical scan speed, a monotonic decrease in the recorded contact-resonance frequency is observed with increasing scan speed. Proper characterization and understanding of this phenomenon is necessary to conduct accurate quantitative imaging using contact-resonance AFM, and other contact-mode AFM techniques, at higher scan speeds. A squeeze film hydrodynamic theory is proposed to explain this phenomenon, and model predictions are compared against the experimental data.
    Language English
    Publishing date 2018-03-21
    Publishing country Germany
    Document type Journal Article
    ZDB-ID 2583584-1
    ISSN 2190-4286
    ISSN 2190-4286
    DOI 10.3762/bjnano.9.87
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: NOVEL AVIBACTERIUM SPECIES ASSOCIATED WITH SINUSITIS AND CONJUNCTIVITIS IN A MERRIAM'S WILD TURKEY (MELEAGRIS GALLOPAVO MERRIAMI) FLOCK IN COLORADO, USA.

    Ellis, Jayne S / MacGlover, Christopher A / Sondgeroth, Kerry S / Brown, Derek / Daniels, Joshua B / Fox, Karen A

    Journal of wildlife diseases

    2022  Volume 58, Issue 4, Page(s) 725–734

    Abstract: A Merriam's Wild Turkey (Meleagris gallopavo merriami) with periocular swelling and periocular skin crusting in Pueblo County, Colorado, USA, was diagnosed with severe catarrhal and fibrinous sinusitis and conjunctivitis. A novel clade of Avibacterium ... ...

    Abstract A Merriam's Wild Turkey (Meleagris gallopavo merriami) with periocular swelling and periocular skin crusting in Pueblo County, Colorado, USA, was diagnosed with severe catarrhal and fibrinous sinusitis and conjunctivitis. A novel clade of Avibacterium was detected in the exudate from this bird. Although eight additional turkeys culled from the affected flock did not have clinical signs or gross lesions, histologically all had mild-to-moderate chronic sinusitis, and infraorbital cultures yielded the same novel clade of Avibacterium that was found in the symptomatic turkey. The presence of this Avibacterium species in the absence of significant disease in some birds suggested that other factors might have been involved in the development of severe sinusitis and conjunctivitis in the symptomatic Wild Turkey. Negative culture results from a distant flock of Wild Turkeys, acquired with similar methods to the affected flock, suggested that this novel species of Avibacterium was not widespread throughout Wild Turkeys in Colorado.
    MeSH term(s) Animals ; Colorado/epidemiology
    Language English
    Publishing date 2022-08-11
    Publishing country United States
    Document type Journal Article
    ZDB-ID 410709-3
    ISSN 1943-3700 ; 0090-3558
    ISSN (online) 1943-3700
    ISSN 0090-3558
    DOI 10.7589/JWD-D-22-00005
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Aortic Stenosis in the Low-Risk Patient: Overview of the Management Options and Possible Permutations.

    Rahmouni, Kenza / Buchko, Max / Boodhwani, Munir / Dick, Alexander / Glover, Christopher / Lam, Buu-Khan / Ruel, Marc / Al-Atassi, Talal

    The Canadian journal of cardiology

    2022  Volume 38, Issue 6, Page(s) 836–839

    MeSH term(s) Aortic Valve ; Aortic Valve Stenosis/diagnosis ; Aortic Valve Stenosis/surgery ; Heart Valve Prosthesis Implantation ; Humans ; Severity of Illness Index ; Transcatheter Aortic Valve Replacement
    Language English
    Publishing date 2022-01-21
    Publishing country England
    Document type Journal Article ; Review
    ZDB-ID 632813-1
    ISSN 1916-7075 ; 0828-282X
    ISSN (online) 1916-7075
    ISSN 0828-282X
    DOI 10.1016/j.cjca.2022.01.015
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: Off-Hours Presentation, Door-to-Balloon Time, and Clinical Outcomes in Patients Referred for Primary Percutaneous Coronary Intervention.

    Rashid, Mohammed K / Wells, George / So, Derek Y / Chong, Aun-Yeong / Dick, Alexander / Froeschl, Michael / Glover, Christopher / Hibbert, Benjamin / Labinaz, Marino / Russo, Juan / Bernick, Jordan / Le May, Michel

    The Journal of invasive cardiology

    2023  Volume 35, Issue 4, Page(s) E185–E193

    Abstract: Objectives: Presentation with ST-segment-elevation myocardial infarction (STEMI) during off-hours may impact timely reperfusion and clinical outcomes. We investigated the association between off-hours presentation, door-to-balloon time, and in-hospital ... ...

    Abstract Objectives: Presentation with ST-segment-elevation myocardial infarction (STEMI) during off-hours may impact timely reperfusion and clinical outcomes. We investigated the association between off-hours presentation, door-to-balloon time, and in-hospital mortality in patients with STEMI referred for primary percutaneous coronary intervention (PCI).
    Methods: We included consecutive patients referred for primary PCI at the University of Ottawa Heart Institute between July 2004 and December 2017. The off-hours group included patients presenting on weekends, statutory holidays, or between 18:00 to 07:59 hours on weekdays. The on-hours group included patients presenting between 08:00 and 17:59 hours on weekdays. The primary clinical outcome was the adjusted in-hospital mortality. The primary quality-of-care indicator was door-to-balloon time.
    Results: A total of 5132 patients were included, with 3152 (61.4%) in the off-hours group and 1980 (38.6%) in the on-hours group. The median door-to-balloon time was longer in the off-hours group compared with the on-hours group (102 minutes vs 77 minutes; P<.001), while the median onset-to-door time was similar (P=.40). There was no difference in the rates of in-hospital mortality (3.5% vs 3.0%; P=.32) or in the adjusted mortality (odds ratio, 1.2; 95% confidence interval, 0.8-1.8; P=.44) between off-hours and on-hours groups. However, door-to-balloon time was an independent predictor of in-hospital mortality (P<.01) and off-hours presentation was an independent predictor of longer door-to-balloon time (P<.001), with an excess of 22.1 minutes.
    Conclusion: Patients treated with primary PCI during off-hours had longer door-to-balloon times. Treatment during off-hours was an independent predictor of longer door-to-balloon time and longer door-to-balloon times were associated with higher mortality.
    MeSH term(s) Humans ; Percutaneous Coronary Intervention ; Angioplasty, Balloon, Coronary ; ST Elevation Myocardial Infarction/diagnosis ; ST Elevation Myocardial Infarction/surgery ; Treatment Outcome ; Myocardial Infarction/therapy ; Hospital Mortality
    Language English
    Publishing date 2023-02-24
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 1154372-3
    ISSN 1557-2501 ; 1042-3931
    ISSN (online) 1557-2501
    ISSN 1042-3931
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article: Source and seasonality of epizootic mycoplasmosis in free-ranging pronghorn (antilocapra americana)

    Johnson, Marguerite / MacGlover, Christopher / Peckham, Erika / Killion, Halcyon / Allen, Samantha E. / Creekmore, Terry / Edwards, William H. / Blaeser, Madison / Davison, McKenzi / Schwalbe, Erin / Wray, Amy K. / Bragg, Thomas K. / Sondgeroth, Kerry S. / Malmberg, Jennifer L.

    Journal of wildlife diseases. 2022 July 25, v. 58, no. 3

    2022  

    Abstract: Mycoplasma bovis is an economically important bacterial pathogen of cattle (Bos taurus) and bison (Bison bison) that most commonly causes pneumonia, polyarthritis, and mastitis. It is prevalent in cattle and ranched bison; however, infections in other ... ...

    Abstract Mycoplasma bovis is an economically important bacterial pathogen of cattle (Bos taurus) and bison (Bison bison) that most commonly causes pneumonia, polyarthritis, and mastitis. It is prevalent in cattle and ranched bison; however, infections in other species are rare. In early 2019, we identified M. bovis in free-ranging pronghorn (Antilocapra americana) in northeastern Wyoming. Here, we report on additional pronghorn mortalities caused by M. bovis, in the same approximately 120-km² geographic region 1 yr later. Genetic analysis by multilocus sequence typing revealed that the mortalities were caused by the same M. bovis sequence type, which is unique among all sequence types documented thus far in North America. To explore whether pronghorn maintain chronic infections and begin assessing M. bovis status in other sympatric species, we used PCR testing of nasal swabs to opportunistically survey select free-ranging ungulates. We found no evidence of subclinical infections in 13 pronghorn sampled from the outbreak area (upper 95% binomial confidence limit [bCL], ∼24.7%) or among 217 additional pronghorn (upper 95% bCL, ∼1.7%) sampled from eight additional counties in Wyoming and 10 in Montana. All mule deer (Odocoileus hemionus; n=231; upper 95% bCL, ∼1.6%) sampled from 11 counties in Wyoming also were PCR negative. To assess the potential for environmental transmission, we examined persistence of M. bovis in various substrates and conditions. Controlled experiments revealed that M. bovis can remain viable for 6 h in shaded water and 2 h in direct sunlight. Our results indicate that environmental transmission of M. bovis from livestock to pronghorn is possible and that seasonality of infection could be due to shared resources during late winter. Further investigations to better understand transmission dynamics, to assess population level impacts to pronghorn, and to determine disease risks among pronghorn and other ungulate taxa appear warranted.
    Keywords Antilocapra americana ; Bison bison ; Mycoplasma bovis ; Odocoileus hemionus ; arthritis ; bison ; cattle ; epizootic diseases ; genetic analysis ; multilocus sequence typing ; mycoplasmosis ; nose ; pathogens ; pneumonia ; solar radiation ; sympatry ; wildlife ; winter ; Montana ; Wyoming
    Language English
    Dates of publication 2022-0725
    Size p. 524-536.
    Publishing place Wildlife Disease Association
    Document type Article
    ZDB-ID 410709-3
    ISSN 1943-3700 ; 0090-3558
    ISSN (online) 1943-3700
    ISSN 0090-3558
    DOI 10.7589/JWD-D-21-00117
    Database NAL-Catalogue (AGRICOLA)

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