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The objective of this panel was to generate recommendations to promote the engagement of front-line emergency department (ED) clinicians in clinical and implementation research.
Panel members conducted semi-structured interviews with 37 Canadian adult and pediatric emergency medicine researchers to elicit barriers and facilitators to clinician engagement in research activities, and to glean strategies for promoting clinician engagement.
Responses were organized by themes, and, based on these responses, recommendations were developed and refined in an iterative fashion by panel members.
We offer eight recommendations to promote front-line clinician engagement in clinical research activities. Recommendations to promote clinician engagement specifically address the creation of a research-friendly culture in the ED, minimizing the burden of data collection on clinical staff through the careful design of data collection tools and the use of research staff, and communication between researchers and clinical staff to promote adherence to study protocols.
The objective of Panel 2b was to present an overview of and recommendations for the conduct of implementation trials and multicentre studies in emergency medicine.
Panel members engaged methodologists to discuss the design and conduct of implementation and multicentre studies. We also conducted semi-structured interviews with 37 Canadian adult and pediatric emergency medicine researchers to elicit barriers and facilitators to conducting these kinds of studies.
Responses were organized by themes, and, based on these responses, recommendations were developed and refined in an iterative fashion by panel members.
We offer eight recommendations to facilitate multicentre clinical and implementation studies, along with guidance for conducting implementation research in the emergency department. Recommendations for multicentre studies reflect the importance of local study investigators and champions, requirements for research infrastructure and staffing, and the cooperation and communication between the coordinating centre and participating sites.
We investigated a mixed outbreak of Legionnaires' disease (LD) and Pontiac fever (PF) at a military base to identify the outbreak's environmental source as well as known legionellosis risk factors. Base workers with possible legionellosis were interviewed and, if consenting, underwent testing for legionellosis. A retrospective cohort study collected information on occupants of the buildings closest to the outbreak source. We identified 29 confirmed and probable LD and 38 PF cases. All cases were exposed to airborne pathogens from a cooling tower. Occupants of the building closest to the cooling tower were 6·9 [95% confidence interval (CI) 2·2–22·0] and 5·5 (95% CI 2·1–14·5) times more likely to develop LD and PF, respectively, than occupants of the next closest building. Thorough preventive measures and aggressive responses to outbreaks, including searching for PF cases in mixed legionellosis outbreaks, are essential for legionellosis control.
Human–wildlife conflicts occur within the context of a complex social–ecological system influenced by a wide variety of social, economic and political forces. Management responses to human–wildlife conflict are based on certain assumptions and perceptions that form the mental models of this system. Understanding these mental models provides opportunity for various stakeholders to engage management staff based on shared components and direct attention to areas of disagreement, and involve organizations that are normally considered to be outside the domain of human–wildlife conflict. Mind mapping was used in this study to identify mental models that people hold about human–wildlife conflict in Namibia, a country that has seen rapid increases in conflict, and to describe the principal factors and variables leading to such conflict. The results indicate that mind mapping is a useful tool for uncovering mental models of conflict and can reveal significant variables in reduction of conflict such as land-use planning and livelihood enhancement.
Carbonate rocks in the Mojave Desert are presented as potential analogues for the carbonates on Mars. Rocks collected from the Little Red Hill site contain iron oxide-bearing coatings that greatly suppress the spectral features due to carbonate of the underlying material and impart a spectral slope. The Mojave Desert was formerly a lush pedogenic soil environment that, over time, transformed into the current arid climate with abundant rock varnish. One niche for microbes in the current desolate environment is inside and underneath the rocks where the microbes profit from solar protection by the iron oxide rock coatings. Carbonates were long predicted to be present on Mars and have recently been detected by instruments on Phoenix and MER and using hyperspectral orbiters such as the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM), the Planetary Fourier Spectrometer (PFS) and the Thermal Emission Spectrometer (TES). We describe here the results of a study of carbonate rocks from the Little Red Hill site of the Mojave Desert that includes X-ray diffraction (XRD), chemistry and visible-infrared reflectance spectroscopy. Coatings on the carbonate rocks greatly reduced the strength of the carbonate bands and caused changes in the shape of some bands. We compare these data with a carbonate outcrop at Nili Fossae, Mars. If microbes once inhabited Mars, similar carbonate rocks with iron oxide coatings could have provided a UV-protected niche there as well. Thus, analysis of carbonate-bearing regions on Mars by future landers would be useful sites to search for biosignatures.
The conventional molecular ion doped polyaniline undergoes dedoping in sea water because the sea water, with pH = 8, induces deprotontation of polyaniline. In this article we report polyaniline complexes that remain conductive in sea water. These complexes are useful for corrosion protection of metals in marine environment and for chromate replacement coatings. The reason for the pH stability of these polyaniline complexes was discussed. The polymeric complexes of polyaniline were used as an additive in an epoxy primer coating on AL7075-T6 without surface pre-treatment of the metal. Corrosion tests show that these polymeric complexes of polyaniline are effective for improving the corrosion inhibition in seawater for aluminum alloys.
Diazoluminomelanin (DALM) is a luminescent polymer belonging to the broader class of conjugated polyphenylene materials, which has shown significant optical activity in response to perturbing fields. In this paper we use semiempirical electronic structure calculations and molecular dynamics simulations to investigate the molecular structure and absorption characteristics of model phenolic oligomers. Molecular dynamics simulations show the polymer backbone can be extremely flexible depending upon the ionization state of the phenolic hydroxyl groups. The interring torsion angle is a critical variable as it relates charge localization effects and electronic excitation energies. Comparison with experimental data demonstrates the need for a multistate basis to describe the absorption properties of this system.
Photoluminescence (PL) and optically-detected magnetic resonance (ODMR) experiments have been performed on undoped GaN epitaxial layers grown on 6H-SiC substrates. The defects observed in these films are compared with those found from previous ODMR studies of undoped GaN layers grown on sapphire substrates. Strong, sharp donor-bound exciton bands at 3.46 -3.47 eV and weak, broad emission bands at 2.2 eV were observed from several 0.7 and 2.6 μm-thick films. In addition, fairly strong shallow donor - shallow acceptor (SD-SA) recombination with a zero-phonon-line at 3.27 eV was found for GaN layers less than 1 μm-thick. The first observation of magnetic resonance on this SD-SA recombination from undoped GaN is reported in this work. Two magnetic resonance features attributed to effective-mass (EM) and deep-donor (DD) states were detected on the 2.2 eV emission bands from all the GaN/6H-SiC films. These resonances were observed previously on similar emission from undoped GaN layers grown on sapphire substrates. The same EM donor resonance, though much weaker, was also found on the SD-SA recombination. However, a resonance associated with shallow acceptor states was not observed on this emission. The weakness of the donor resonance arises from the weak spin-dependence of the recombination mechanism involving spin-thermalized shallow acceptors. The absence of an EM acceptor is due to the broadening of the resonance through the spreading of the acceptor g-values by random strains in these films.
Quantum confinement in nanoscale Si structures is widely believed to be responsible for the visible luminescence observed from anodically etched porous silicon (por-Si), but little is known about the actual size or shape of these structures. Extended x-ray absorption fine structure data from a wide variety of por-Si samples show significantly reduced average Si coordination numbers due to the sizable contribution of surface-coordinated H. (The H/Si ratios, as large as 1.2, were independently confirmed by ir-absorption and α-recoil measurements.) The Si coordinations imply very large surface/volume ratios, enabling the average Si structures to be identified as crystalline particles (not wires) whose dimensions are typically <15 Å. Comparison of the size-dependent peak luminescence energies with those of oxidized Si nanocrystals, whose shapes are known, shows remarkable agreement. Furthermore, near-edge x-ray absorption fine structure measurements of the nanocrystals shows the outer oxide and interfacial suboxide layers to be constant over a wide range of nanocrystal sizes. The combination of these results effectively rules out surface species as being responsible for the observed visible luminescence in por-Si, and strongly supports quantum confinement as the dominant mechanism occurring in Si particles which are substantially smaller than previously reported or proposed.
Alkali-silica reaction, sulfate attack, and reinforcing steel corrosion can compromise the long-term durability of concrete structures. The anticipated economic impact of an extensive infrastructure repair scheme has produced a renewed interest in the development of advanced characterization methods to assess the degree of deterioration in the concrete experiencing these deleterious reactions. The products of the alkali silica reaction, sulfate attack, and corrosion as well as the cement hydration products are extremely sensitive to humidity. Consequently, characterization techniques that require high vacuum or drying, as many existing techniques do, are not particularly appropriate for the study of these reactions in concrete as artifacts are introduced. A high resolution instrument which allows the examination of these reactions and their products without drying and at normal pressures will promote understanding of the reactions and provide further insight into means of mitigating the damage they cause. Only soft x-ray transmission microscopy provides the required high spatial resolution to observe the reaction process in situ. The alkali-silica reaction can be observed over time, in a wet condition, and at normal pressures, features unavailable with most other high resolution techniques. Soft x-rays also reveal information on the internal structure of the sample. This paper reviews published and ongoing applications of soft x-ray transmission microscopy for the study of expansive reactions that occur in concrete.
The usefulness of the glycaemic index (GI) of a food for practical advice for individuals with diabetes or the general population depends on its reliability, as estimated by intra-class coefficient (ICC), a measure having values between 0 and 1, with values closer to 1 indicating better reliability. We aimed to estimate the ICC of the postprandial blood glucose response to glucose and white bread, instant mashed potato and chickpeas using the incremental area under the curve (iAUC) and the GI of these foods. The iAUC values were determined in twenty healthy individuals on three and four occasions for white bread and glucose, respectively, and for potato and chickpeas on a single occasion. The ICC of the iAUC for white bread and glucose were 0·50 (95 % CI 0·27, 0·73) and 0·49 (95 % CI 0·22, 0·75), respectively. The mean GI of white bread was 81 (95 % CI 74, 90) with a reliability of 0·27 indicating substantial within-person variability. The GI of mashed potato and chickpeas were 87 (95 % CI 76, 101) and 28 (95 % CI 22, 37) respectively with ICC of 0·02 and 0·40.The ICC of the iAUC were moderate and those of the GI fair or poor, indicating the heterogeneous nature of individuals' responses. The unpredictability of individual responses even if they are the result of day-to-day variation places limitations on the clinical usefulness of GI. If the very different GI of potato and chickpeas are estimates of an individual's every-day response to different foods, then the GI of foods may provide an indication of the GI of a long-term diet.
To assist field workers in program evaluation and to explicitly discuss program strengths and weaknesses, a practical method to estimate the effectiveness of public health interventions within the existing program capacity was developed. The method and materials were tested in seven countries (Afghanistan, Zimbabwe, Tanzania, Uganda, Guatemala, the Philippines, and Ghana). In this method, four core components are assessed using a questionnaire: (1) the efficacy of the intervention; (2) the level of existing human resources (i.e., quality of recruitment, training, and continuing education); (3) the infrastructure (i.e., supplies, salary, transportation, and supervision); and (4) the level of community support (i.e., access and demand). Using the assessment tool provided, program staff can determine if all necessary elements are in place for a successful program that can deliver the specific intervention. Based on the results of the assessment program, weaknesses can be identified, explicitly discussed, and addressed.The usefulness of this tool in humanitarian relief may be twofold: (1) to assess the design and implementation of effective programs; and (2) to highlight the inevitable need for capacity building as the disaster situation evolves.
A prospective cohort study was conducted in five purposively-sampled agro-ecological zone
(AEZ)-grazing system strata in Murang’a District, Kenya, between March 1995 and June 1996.
The study strata were selected based on a preliminary characterization study to represent the
widest range of risks to East Coast fever (ECF) in the District and included zero-grazing and
open-grazing farms. In total, 225 calves from 188 smallholder farms were examined from birth
to 6 months of age and visited within the first 2 weeks of life and thereafter at bi-weekly
intervals for up to 14 visits.
The purpose of the study was to characterize the differences in epidemiology (risks of
infection, morbidity and mortality) and potential control of ECF between the selected strata.
Evidence of Theileria parva infection was assessed by increased antibody levels as measured in
an indirect ELISA assay by the percent positivity (PP) of serum samples relative to a strong
positive reference serum.
Sero-conversion risks of T. parva were highest in the open-grazing strata. Antibody
prevalence in adult cattle and ECF morbidity and mortality risks were also highest in open-grazing strata. While different, all five AEZ-grazing strata were considered to be endemically
unstable for ECF. East Coast fever challenge was low in all zero-grazing strata and this
challenge is likely to remain low due to continuing intensification of smallholder farming in the
central highlands. In the open-grazing strata, there was higher challenge and a greater impact
The fast ignitor concept for inertial confinement fusion relies on the generation of hot electrons, produced by a short-pulse ultrahigh intensity laser, which propagate through high-density plasma to deposit their energy in the compressed fuel core and heat it to ignition. In preliminary experiments designed to investigate deep heating of high-density matter, we used a 20 joule, 0.5–30 ps laser to heat solid targets, and used emission spectroscopy to measure plasma temperatures and densities achieved at large depths (2–20 microns) away from the initial target surface. The targets consisted of an Al tracer layer buried within a massive CH slab; H-like and He-like line emission was then used to diagnose plasma conditions. We observe spectra from tracer layers buried up to 20 microns deep, measure emission durations of up to 200 ps, measure plasma temperatures up to Te=650 eV, and measure electron densities above 1023 cm−3. Analysis is in progress, but the data are in reasonable agreement with heating simulations when space-charge induced inhibition is included in hot-electron transport, and this supports the conclusion that the deep heating is initiated by hot electrons.
Robert Perry, Department of Neuropathology, Newcastle General Hospital,Ian McKeith, University of Newcastle upon Tyne,Elaine Perry, MRC Neurochemical Pathology Unit, Newcastle General Hospital
Two alternative hypotheses – that there is either a unitary or a multiple neuropathological basis for dementia in diseases associated with Lewy bodies – are considered in relation to Parkinson's disease (PD) and Lewy body dementia (LBD including senile dementia of Lewy body type, SDLT). Densities of limbic (cingulate) cortical Lewy bodies, neocortical Lewy bodies, neocortical plaques, neocortical tangles, Braak staging, and Apo E frequency have been quantified in PD (demented and nondemented), SDLT, and Alzheimer's disease (AD with presenile and senile onset). Of these parameters the mean density of cingulate Lewy bodies is significantly greater in SDLT compared with all PD cases. There is no obvious correlation between Lewy body density and cognitive impairment assessed using a simple test of mental ability, and other measures of mental function in LBD may need to be considered. Since there is no absolute density of limbic Lewy bodies that clearly differentiates SDLT or demented PD cases from all nondemented PD cases, neuropathological criteria may need to incorporate severity of Alzheimer-type pathology as an additional optional factor. Mean neocortical plaque density is significantly lower in SDLT compared with AD cases but it is also significantly higher than in demented and nondemented PD cases, and higher than densities in normals. Even so, neocortical plaque density does not itself differentiate all SDLT cases from the normal. It is likely that the biological basis for dementia or psychoses in LBD, a cardinal feature of which is fluctuating symptomatology, is in part a functional or neurochemical abnormality.