1,995 research outputs found
Recommended from our members
Assessment of the Angolan (CHERRT) Mobile Laboratory Curriculum for Disaster and Pandemic Response
Introduction: As of April 5, 2020, the World Health Organization reported over one million confirmed cases and more than 62,000 confirmed coronavirus (COVID-19) deaths affecting 204 countries/ regions. The lack of COVID-19 testing capacity threatens the ability of both the United States (US) and low middle income countries (LMIC) to respond to this growing threat, The purpose of this study was to assess the effectiveness through participant self-assessment of a rapid response team (RRT) mobile laboratory curriculumMethods: We conducted a pre and post survey for the purpose of a process improvement assessment in Angola, involving 32 individuals. The survey was performed before and after a 14-day training workshop held in Luanda, Angola, in December 2019. A paired t-test was used to identify any significant change on six 7-point Likert scale questions with α< 0.05 (95% confidence interval).Results: All six of the questions – 1) “I feel confident managing a real laboratory sample test for Ebola or other highly contagious sample;” 2) “I feel safe working in the lab environment during a real scenario;” 3) “I feel as if I can appropriately manage a potentially highly contagious laboratory sample;” 4)“I feel that I can interpret a positive or negative sample during a suspected contagious outbreak;” 5) “I understand basic Biobubble/mobile laboratory concepts and procedures;” and 6) “I understand polymerase chain reaction (PCR) principles” – showed statistical significant change pre and post training. Additionally, the final two questions – “I can more effectively perform my role/position because of the training I received during this course;” and “This training was valuable” – received high scores on the Likert scale.Conclusion: This Angolan RRT mobile laboratory training curriculum provides the nation of Angola with the confidence to rapidly respond and test at the national level a highly infectious contagion in the region and perform on-scene diagnostics. This mobile RRT laboratory provides a mobile and rapid diagnostic resource when epidemic/pandemic resource allocation may need to be prioritized based on confirmed disease prevalence
The stability of the spectator, Dirac, and Salpeter equations for mesons
Mesons are made of quark-antiquark pairs held together by the strong force.
The one channel spectator, Dirac, and Salpeter equations can each be used to
model this pairing. We look at cases where the relativistic kernel of these
equations corresponds to a time-like vector exchange, a scalar exchange, or a
linear combination of the two. Since the model used in this paper describes
mesons which cannot decay physically, the equations must describe stable
states. We find that this requirement is not always satisfied, and give a
complete discussion of the conditions under which the various equations give
unphysical, unstable solutions
Evaluation of the Free Energy of Two-Dimensional Yang-Mills Theory
The free energy in the weak-coupling phase of two-dimensional Yang-Mills
theory on a sphere for SO(N) and Sp(N) is evaluated in the 1/N expansion using
the techniques of Gross and Matytsin. Many features of Yang-Mills theory are
universal among different gauge groups in the large N limit, but significant
differences arise in subleading order in 1/N.Comment: 10 pages; no figures; LaTe
Microcanonical entropy inflection points: Key to systematic understanding of transitions in finite systems
We introduce a systematic classification method for the analogs of phase
transitions in finite systems. This completely general analysis, which is
applicable to any physical system and extends towards the thermodynamic limit,
is based on the microcanonical entropy and its energetic derivative, the
inverse caloric temperature. Inflection points of this quantity signal
cooperative activity and thus serve as distinct indicators of transitions. We
demonstrate the power of this method through application to the long-standing
problem of liquid-solid transitions in elastic, flexible homopolymers.Comment: 4 pages, 3 figure
An Examination of SOFC Anode Functional Layers Based on Ceria in YSZ
The properties of solid oxide fuel cell (SOFC) anode functional layers prepared by impregnation of ceria and catalytic metals into porous yttria-stabilized zirconia (YSZ) have been examined for operation at 973 K. By varying the thickness of the functional layer, the conductivity of the ceria-YSZ composite was determined to be only 0.015–0.02 S/cm. The initial performance of anodes made with ceria loadings of 40 or 60 wt % were similar but the anodes with lower loadings lost conductivity above 1073 K due to sintering of the ceria. The addition of dopant levels of catalytic metals was found to be critical. The addition of 1 wt % Pd or Ni decreased the anode impedances in humidified H2 dramatically, while the improvement with 5 wt % Cu was significant but more modest. Pd doping also decreased the anode impedance in dry CH4 much more than did Cu doping; however, addition of either Pd or Cu led to similar improvements for operation in n-butane. Based on these results, suggestions are made for ways to improve SOFC anode functional layers
The Current Status of the Limnology and Bottom Fauna of Lakes West and East Okoboji
Lakes West and East Okoboji, Dickinson County, Iowa, were the site of a 1970 summer investigation on the density and diversity within the macroscopic bottom organisms, physical and chemical measurements of the water and substratum chemistry study. These data on Lake West Okoboji were compared with a 1918 and 1950 study of the macroscopic bottom fauna, water analyses dating from 1934, and oxygen and temperature data from as far back as 1915. The sparse species composition of the bottom fauna has remained unchanged; however, pollution indicator tubificid worms have increased in density. Water analysis, oxygen, and temperature data are little changed from earlier studies. Few data have been collected in previous years on Lake East Okoboji. Apparent cultural eutrophication has occurred in the last 60 years, causing extreme nuisance blooms of blue-green algae
A Study of Thermal Stability and Methane Tolerance of Cu-Based SOFC Anodes with Electrodeposited Co
Cu-based, solid oxide fuel cell (SOFC) electrodes were modified by electrodeposition of Co. The addition of only 5-vol% Co by electrodeposition significantly improved the thermal stability compared to either Cu-ceria-YSZ, Cu-Co-ceria-YSZ, or Co-ceria-YSZ electrodes prepared only by impregnation with much higher metal loadings, demonstrating that electrodeposited metal layers form metal films with better connectivity. In the absence of Co, SEM showed structural changes in the impregnated Cu after heating to 1173 K in humidified H2 and these changes caused large increases in the ohmic resistance of fuel cells, as measured by impedance spectroscopy. In contrast, the ohmic resistance of a cell with 13-vol% Cu, 9-vol% ceria, and 5-vol% Co increased only slightly after 48 h at 1173 K in humidified H2. While a Co-ceria-YSZ composite was found to form large amounts of carbon upon exposure to dry CH4 at 1073 K for 3 h, the Co-Cu-ceria-YSZ composites did not form measurable amounts of carbon for the same conditions. XPS results for a Cu foil with a 250-nm Co film demonstrated that Cu migrates to the surface of the Co upon heating above 873 K, forming a stable Cu layer that appears to be approximately one monolayer thick. The implication of these results for the development of practical SOFC electrodes for the direct utilization of hydrocarbons is discussed
The Current Status of the Limnology and Bottom Fauna of Lakes West and East Okoboji
Lakes West and East Okoboji, Dickinson County, Iowa, were the site of a 1970 summer investigation on the density and diversity within the macroscopic bottom organisms, physical and chemical measurements of the water and substratum chemistry study. These data on Lake West Okoboji were compared with a 1918 and 1950 study of the macroscopic bottom fauna, water analyses dating from 1934, and oxygen and temperature data from as far back as 1915. The sparse species composition of the bottom fauna has remained unchanged; however, pollution indicator tubificid worms have increased in density. Water analysis, oxygen, and temperature data are little changed from earlier studies. Few data have been collected in previous years on Lake East Okoboji. Apparent cultural eutrophication has occurred in the last 60 years, causing extreme nuisance blooms of blue-green algae
- …