5,424 research outputs found
Disarmed : the radical life and legacy of Michael MJ Sharp /
No full text"A powerful story of one man's radical commitment to peacemaking. Michael "MJ" Sharp was a modern Mennonite armed with wit and intellect, but not a gun. The son of a Mennonite pastor, he demonstrated a gift for listening and persuading early in life. His efforts to approach others with acknowledgement rather than judgement gave him the ability to connect on a level very few managed. He also honed a deep commitment to peace, and after college he joined the Mennonite Mission Network and moved to Germany, where he persuaded soldiers to choose peace and free them of their violent systems. At 34 years old, MJ was working for the United Nations Group of Experts in the Democratic Republic of the Congo-urging rebels to lay down their weapons-when he was murdered, likely assassinated alongside his colleague Zaida Catalán by those with government ties. This compelling account of MJ's life, death, and legacy from longtime journalist Marshall V. King explores what compelled Sharp to travel the world working for peace and the ongoing impact of his life and death in the ongoing story of Christian peacemaking in a war-torn world"--Includes bibliographical references."A powerful story of one man's radical commitment to peacemaking. Michael "MJ" Sharp was a modern Mennonite armed with wit and intellect, but not a gun. The son of a Mennonite pastor, he demonstrated a gift for listening and persuading early in life. His efforts to approach others with acknowledgement rather than judgement gave him the ability to connect on a level very few managed. He also honed a deep commitment to peace, and after college he joined the Mennonite Mission Network and moved to Germany, where he persuaded soldiers to choose peace and free them of their violent systems. At 34 years old, MJ was working for the United Nations Group of Experts in the Democratic Republic of the Congo-urging rebels to lay down their weapons-when he was murdered, likely assassinated alongside his colleague Zaida Catalán by those with government ties. This compelling account of MJ's life, death, and legacy from longtime journalist Marshall V. King explores what compelled Sharp to travel the world working for peace and the ongoing impact of his life and death in the ongoing story of Christian peacemaking in a war-torn world"-
Wetting and spreading of a surfactant film on solid particles: influence of sharp edges and surface irregularities
No full textIn addition to particle size and surface chemistry, the shape of particles plays an important role in their wetting and displacement by the surfactant film in the lung. The role of particle shape was the subject of our investigations using a model system consisting of a modified Langmuir-Wilhelmy surface balance. We measured the influence of sharp edges (lines) and other highly curved surfaces, including sharp corners or spikes, of different particles on the spreading of a dipalmitoylphosphatidyl (DPPC) film. The edges of cylindrical sapphire plates (circular curved edges, 1.65 mm radius) were wetted at a surface tension of 10.7 mJ/m2 (standard error (SE) = 0.45, n = 20) compared with that of 13.8 mJ/m2 (SE = 0.20, n = 20) for cubic sapphire plates (straight linear edges, edge length 3 mm) (p 0.05). The surfaces of the plates showed significantly higher resistance to spreading compared to that of the edges, as substantially lower surface tensions were required to initiate wetting (p 0.05), respectively, whereas the surfaces were wetted at 3.8 mJ/m2 (SE = 0.89, n = 20) and 5.8 mJ/m2 (SE = 0.52, n = 20) (p < 0.05), respectively. Further experiments with pollen of malvaceae and maize (spiky and fine knobbly surfaces) were wetted at 10.0 mJ/m2 (SE = 0.52, n = 10) and 22.75 mJ/m2 (SE = 0.81, n = 10), respectively (p < 0.05). These results show that resistance to spreading of a DPPC film on various surfaces is dependent on the extent these surfaces are curved. This is seen with cubic sapphire plates which have at their corners a radius of curvature of about 0.75 microm, spiky malvaceae pollen with an even smaller radius on top of their spikes, or talc with various highly curved surfaces. These highly curved surfaces resisted wetting by the DPPC film to a higher degree than more moderately curved surfaces such as those of cylindrical sapphire plates, maize pollens, or polystyrene spheres, which have a surface free energy similar to that of talc but a smooth surface. The macroscopic plane surfaces of the particles demonstrated the greatest resistance to spreading. This was explained by the extremely fine grooves in the nanometer range, as revealed by electron microscopy. In summary, to understand the effects of airborne particles retained on the surfaces of the respiratory tract, and ultimately their pathological potential, not only the particle size and surface chemistry but also the particle shape should be taken in consideration
Self-compression of 4.9 µm pulses to sub-40 fs with 2 mJ energy in Zinc Sulfide
No full textNonlinear self-compression of few-cycle multi-mJ pulses at 4.9 µm in ZnS is presented. 80 fs input pulses are compressed to 37 fs with 2.1 mJ energy at a 1 kHz repetition rate. © 2024 The Author(s
Intra-annual and intra-seasonal flow dynamics of a High Arctic polythermal valley glacier
Get PDFMeasurements of surface dynamics on polythermal John Evans Glacier, Nunavut, Canada, over two winter periods and every 7-10 days throughout two melt seasons (June-July 2000, 2001) provide new insight into spatio-temporal patterns of High Arctic glacier dynamics. In the lower ablation zone, mean annual surface velocities are 10-21m a-1, but peak velocities up to 50% higher are attained during late June/early July. In the upper ablation zone and lower accumulation zone, mean annual surface velocities are typically 10-18 m a-1, and peak velocities up to 40% higher occur during late July. In the upper accumulation zone, mean annual surface velocities are 2-9 m a-1, and motion in mid- to late July exceeds this by up to 10%. Rapid drainage of ponded supraglacial water in the upper ablation zone to an initially distributed subglacial drainage system in mid-June may force excess surface motion in the warm-based lower glacier. The data indicate that the duration of the velocity response may be related to the rate of channelization of the basal drainage, and the velocity response may be transmitted up-glacier by longitudinal coupling. An increase in surface velocities in the middle glacier in late July occurs in conjunction with the opening of two further moulins in the accumulation zone
Exact sharp-fronted solutions for nonlinear diffusion on evolving domains
No full textAbstract
Models of diffusive processes that occur on evolving domains are frequently employed to describe biological and physical phenomena, such as diffusion within expanding tissues or substrates. Previous investigations into these models either report numerical solutions or require an assumption of linear diffusion to determine exact solutions. Unfortunately, numerical solutions do not reveal the relationship between the model parameters and the solution features. Additionally, experimental observations typically report the presence of sharp fronts, which are not captured by linear diffusion. Here we address both limitations by presenting exact sharp-fronted solutions to a model of degenerate nonlinear diffusion on a growing domain. We obtain the solution by identifying a series of transformations that converts the model of a nonlinear diffusive process on an evolving domain to a nonlinear diffusion equation on a fixed domain, which admits known exact solutions for certain choices of diffusivity functions. We determine expressions for critical time scales and domain growth rates such that the diffusive population never reaches the domain boundaries and hence the solution remains valid
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The development of smart-bandage technologies
No full textHealthcare associated infections of wound sites are a complex problem with substantial effects on patient morbidity and financial ramifications to healthcare bodies. The increasing interest in novel diagnostic strategies and preventing infections have led to an incursion of research into the topic. Whilst most emphasis has been placed on preventing wound infections, the bacterial flora is an ever present risk to the compromised host. In contrast with the majority of research developing antibacterial smart-dressings, the research detailed within describes the development of in-situ electrochemical sensor assemblies suitable for incorporation within traditional or ‘smart’ wound dressings. Sensor developments have led to prototype construction of a multitude of sensing substrates capable of quantitative analyses for the identification of infection. The key developments contained within highlight both generic and organism-specific sensors which can reliably monitor key chemical components of a wound exudate to allow sampling-free infection diagnostics
Correction to: Chamoun et al., Bacterial pathogenesis and interleukin-17: interconnecting mechanisms of immune regulation, host genetics, and microbial virulence that influence severity of infection
No full textChamoun MN, Blumenthal A, Sullivan MJ, Schembri MA, Ulett GC. 2018. Bacterial pathogenesis and interleukin-17: interconnecting mechanisms of immune regulation, host genetics, and microbial virulence that influence severity of infection. Critical Reviews in Microbiology. https://doi.org/10.1080/1040841X.2018.1426556.
When the above article was first published online, the below three corrections were missed.
The author ‘Antje Blumenthal’ was wrongly affiliated to the affiliation “cSchool of Chemistry and Molecular Biosciences, and Australian Infectious Disease Research Centre, The University of Queensland, Brisbane, Australia”. Now this affiliation has been removed for this author.
The affiliation ‘bTranslational Research Institute, The University of Queensland Diamantina Institute, Woolloongabba, Australia’ of the author ‘Antje Blumenthal’ should read ‘bThe University of Queensland Diamantina Institute, Translational Research Institute, Brisbane, Australia’.
In Table 3, the sentence ‘Benefit of manipulating IL-17 levels to improve immunization strategies M. tuberculosis’ should read “Benefit of manipulating IL-17 levels to improve immunization strategies against M. tuberculosis”.No Full Tex
Generation of 22-mJ, 2.0-ps Pulses from a 1-kHz Ho:YLF Regenerative Chirped Pulse Amplifier
No full textWe report a CW-pumped Ho:YLF regenerative amplifier (RA) delivering pulses with 22.5-mJ energy and 2.0-ps duration at 1 kHz. The RA emitting at 2051 nm is broadband-seeded and implemented in a chirped pulse amplification system. © 2024 The Author(s
Colorimetric and Resistive Polymer Electrolyte Thin Films for Real-time Humidity Sensors
No full textWe have developed fast responsive, colorimetric and resistive-type polymeric humidity sensors from a series of self-assembled poly(styrenesulfonate-methylbutylene) (PSS-b-PMB) block copolymers with tailored hygroscopic properties. In dry state, the PSS-b-PMB films exhibit hexagonal cylindrical morphology where hydrophobic PMB cylinders are dispersed within a PSS matrix. Under levels of humidity, the PSS-b-PMB thin films self-displayed discernible reflective color changes, covering almost entire visible light regions from violet (RH = 20%) to red (RH = 95%). The sensors also revealed a few orders of magnitude changes in impedance with exposure to humid air by taking advantages of strong polymer electrolytes characteristics. Remarkably, the time to complete the changes in the signals was only a few seconds, as rationalized by good connectivity of the PSS domains and short water diffusion pathways in nanometer scales. Repeated hydration/dehydration tests demonstrated reliable sensor properties, which is in sharp contrast to the poor stability of PSS homopolymer sensors lacking organization.X114235sciescopu
Cyclotron amplification of whistler-mode waves: a parametric study relevant to discrete VLF emissions in the earth's magnetosphere
No full textWe study the non linear amplification of VLF waves in the earth's magnetosphere. Particular attention is paid to zero order distribution functions of electrons in which there is a sharp step with respect to parallel velocity. It is shown that such steps strongly favour both the linear and non linear amplification processes. The results obtained are discussed in the light of recent observations of VLF emissions, particularly those of Bell and co workers at Stanford University
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