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In preparation for a multisite antibiotic stewardship intervention, we assessed knowledge and attitudes toward management of asymptomatic bacteriuria (ASB) plus teamwork and safety climate among providers, nurses, and clinical nurse assistants (CNAs).
Prospective surveys during January–June 2018.
All acute and long-term care units of 4 Veterans’ Affairs facilities.
The survey instrument included 2 previously tested subcomponents: the Kicking CAUTI survey (ASB knowledge and attitudes) and the Safety Attitudes Questionnaire (SAQ).
A total of 534 surveys were completed, with an overall response rate of 65%. Cognitive biases impacting management of ASB were identified. For example, providers presented with a case scenario of an asymptomatic patient with a positive urine culture were more likely to give antibiotics if the organism was resistant to antibiotics. Additionally, more than 80% of both nurses and CNAs indicated that foul smell is an appropriate indication for a urine culture. We found significant interprofessional differences in teamwork and safety climate (defined as attitudes about issues relevant to patient safety), with CNAs having highest scores and resident physicians having the lowest scores on self-reported perceptions of teamwork and safety climates (P < .001). Among providers, higher safety-climate scores were significantly associated with appropriate risk perceptions related to ASB, whereas social norms concerning ASB management were correlated with higher teamwork climate ratings.
Our survey revealed substantial misunderstanding regarding management of ASB among providers, nurses, and CNAs. Educating and empowering these professionals to discourage unnecessary urine culturing and inappropriate antibiotic use will be key components of antibiotic stewardship efforts.
Positron emission tomography (PET) imaging of brain amyloid beta is now clinically available in several countries including the United States and the United Kingdom, but not Canada. It has become an established technique in the field of neuroimaging of aging and dementia, with data incorporated in the new consensus guidelines for the diagnosis of Alzheimer disease and predementia Alzheimer’s disease–related conditions. At this point, there are three US Food and Drug Administration– and European Union–approved tracers. Guided by appropriate use criteria developed in 2013 by the Alzheimer’s Association and the Society of Nuclear Medicine and Molecular Imaging, the utility of amyloid imaging in medical practice is now supported by a growing body of research. In this paper, we aimed to provide an update on the 2012 Canadian consensus guidelines to dementia care practitioners on proper use of amyloid imaging. We also wished to generate momentum for the industry to submit a new drug proposal to Health Canada. A group of local, national, and international dementia experts and imaging specialists met to discuss scenarios in which amyloid PET could be used appropriately. Peer-reviewed and published literature between January 2004 and May 2015 was searched. Technical and regulatory considerations pertaining to Canada were considered. The results of a survey of current practices in Canadian dementia centers were considered. A set of specific clinical and research guidelines was agreed on that defines the types of patients and clinical circumstances in which amyloid PET could be used in Canada. Future research directions were also outlined, notably the importance of studies that would assess the pharmaco-economics of amyloid imaging.
The role of heterotrophic biofilm of water–sediment interface in detoxification processes was tested in abiotic and biotic conditions under laboratory conditions. Three toxicants, a herbicide (Diuron), a fungicide (Dimethomorph) and an insecticide (Chlorpyrifos-ethyl) have been tested in water percolating into columns reproducing hyporheic sediment. The detoxification processes were tested by comparing the water quality after 18 days of percolation with and without heterotrophic biofilm. Tested concentrations were 30 μg.L−1 of Diuron diluted in 0.1% dimethyl sulfoxide (DMSO), 2 μg.L−1 of Dimethomorph and 0.1 μg.L−1 of Chlorpyrifos-ethyl. To characterise the detoxification efficiency of the system, we performed genotoxicity bioassays in amphibian larvae and rotifers and measured the respiration and denitrification of sediments. Although the presence of biofilm increased the production of N-(3,4 dichlorophenyl)-N-(methyl)-urea, a metabolite of diuron, the toxicity did not decrease irrespective of the bioassay. In the presence of biofilm, Dimethomorph concentrations decreased compared with abiotic conditions, from 2 μg.L−1 to 0.4 μg.L−1 after 18 days of percolation. For both Dimethomorph and Chlorpyrifos-ethyl additions, assessment of detoxification level by the biofilm depended on the test used: detoxification effect was found with amphibian larvae bioassay and no detoxification was observed with the rotifer test. Heterotrophic biofilm exerts a major influence in the biochemical transformation of contaminants such as pesticides, suggesting that the interface between running water and sediment plays a role in self-purification of stream reaches.
Combining Bisphophonates (BPs) and Calcium Phosphate Cement (CPC) to form a new medical device for the local treatment of Osteoporosis is a promising challenge. Our formulation was optimized from an apatitic-type CPC and we have shown that the best solution consists in introducing the bisphosphonate (Alendronate) in the calcium deficient apatite (CDA), a solid component of the cement, through a chemical exchange reaction. The cement obtained was characterized by 31P NMR and high frequency impedance for monitoring the CPC setting. The presence of Alendronate in the cement was also demonstrated by 31P NMR which has been also used to characterize the chemical transformation of α-TCP (main component of the apatitic cement) during the setting process. BP absorption/desorption experiments have been realized on cement blocks, under continuous flow condition, to model the release profile of the Alendronate. In vivo experiments showed promising results in terms of resorbability of the Alendronate–loaded cement while promoting new bone formation. The same methodology is considered to introduce gallium, a potential inhibitor of osteoclastic resorption, in a CPC formulation. First experiments have shown that gallium can be incorporated in calcium phosphate ceramics (i.e. β-TCP) where gallium is part of the network.
Recent Scientific Writings about Consequences of disasters on Workers Danielle Maltais, Ph.D. and Simon Gauthier, M.Sc. University of Quebec in Chicoutimi (UQAC) When an application of emergency measures is issued following a natural or technological disaster, or a disaster caused by human negligence, in many countries social workers and nurses play a central role in the support to the victims not only during the period of social disturbance but also at the time of the return to a normal life. These workers sometimes find themselves plunged within various intervention sectors where work conditions are often difficult. Once juxtaposed to the characteristics attached to disasters (nature, suddenness, duration, intensity, etc), the characteristics of the workers (intervention skills, training received, intrinsic efforts made, etc) and to the characteristics of the organizations (expectations towards their employees, organizational support offered to the employees, extrinsic efforts required, etc), these conditions increase their level of vulnerability by exposing them to environments harsh to manage. This vulnerability experienced by the workers in an emergency period can be reflected through symptoms such as anxious disorders and exhaustion. This poster will present the major findings of recent studies in this field (impact of disaster on the psychological health of workers) while under lighting personal, contextual and organizational factors which either contribute to the presence of psychological health issues for the workers or facilitate their resilience.
The formation of intermetallic compounds (IMC) and its effects at the interface between different metals has always been of interest for the electronics industry, contacts manufacturers and users.
The purpose of this work is primarily to develop an in situ technique of thermally aging metallic samples within the vacuum chamber of a scanning electron microscope (SEM).
This setup enables ongoing observation of the formation and growth of intermetallic compounds within the chamber.
Due to the amount of data available in literature, copper-tin specimens were chosen as a basis to validate the technique.
Once the samples were thermally aged, energy dispersive X-ray (EDX) analyses as well as electron backscattered diffraction (EBSD) were done on the surfaces.
Ex situ nano-indentation measurements were also performed on the IMC. Results have shown that the IMC formation can be observed while aging within a SEM chamber.
Recent information on epidemiology and management of herpes zoster (HZ) and post-herpetic neuralgia (PHN), a painful complication of HZ, is scarce. The objective of this study was to document the burden of HZ and PHN in the United Kingdom. This retrospective analysis of the UK General Practice Research Database aimed to estimate HZ incidence and proportion of HZ patients developing PHN and to assess management costs in immunocompetent individuals aged ⩾50 years. A cohort of 27 225 HZ patients was selected, corresponding to an incidence of 5·23/1000 person-years. Respectively 19·5% and 13·7% of patients developed PHN at least 1 and 3 months after HZ diagnosis. Mean direct cost was £103 per HZ patient and £341 and £397 per PHN episode (1- and 3-month definition respectively). Both HZ and PHN costs increased markedly with pain severity. This study confirms that HZ and PHN are frequent and costly diseases in the United Kingdom.
Metal-matrix composites are produced from Al powder and 30 vol% of icosahedral Al–Cu–Fe quasi-crystalline particles using a hot isostatic pressing technique. It is demonstrated that the initial icosahedral phase is transformed into the ω-Al70Cu20Fe10 tetragonal phase during the hot isostatic pressing (HIP) process. The mechanical properties of the composite were evaluated over the temperature range 293 to 773 K by performing compression tests at constant strain rate. The temperature dependence of the yield stress gives evidence of two temperature regimes with a transition temperature at approximately 423 K. Strain-rate sensitivity measurements support the change in rate-controlling deformation mechanisms at this temperature. It is proposed that cross-slip and/or climb mechanism control plastic flow. Finally, it is suggested that the phase transformation of the particle contributes positively to the improvement of the mechanical properties.
The bulk lifetime
and diffusion length
Ln of minority carriers vary through the height of a cast
multicrystalline silicon (mc-Si) block. This variation is due to the
segregation of metallic impurities during the directional solidification and
the native impurity concentrations increase from the bottom to the top of
the ingot, which is solidified last, while the ingot bottom, which is
solidified first, is contaminated by the contact with the crucible floor. It
is of interest to verify if a correlation exists between the bulk lifetime
of as cut wafers and the conversion efficiency
cells. In a very large ingot (>310 kg), it was found that
, in raw wafers,
in phosphorus diffused
ones and Ln in diffused wafers are smaller in the top and in the bottom
of the ingot. The same evolution is observed in solar cells, however the
diffusion length values Lcel in the central part of the ingot are
markedly higher than those found in diffused wafers, due to the in-diffusion
of hydrogen from the SiN-H antireflection coating layer. The variations of
and those of
, along the ingot height, are well
correlated, suggesting that the evaluation of
can predict the
properties of the devices. In addition, segregation phenomena around the
grain boundaries are observed at the bottom of the ingots, due to a marked
contamination by the crucible floor, and at its top where impurities are
accumulated. These phenomena are linked to the long duration of the
solidification process and the large amount of imperfect silicon used to
cast the ingot.
Frédéric Gauthier, Division of Surgery, Federation of Paediatrics, Centre Hospitalier Universitaire Bicêtre, France,
Danièle Pariente, Division of Radiology, Federation of Paediatrics, Centre Hospitalier Universitaire Bicêtre, France,
Sophie Branchereau, Division of Surgery, Federation of Paediatrics, Centre Hospitalier Universitaire Bicêtre, France,
Mark D. Stringer, Children's Liver and GI Unit, St James's University Hospital, Leeds, UK
Gastrointestinal bleeding related to portal hypertension (PH) in children may be life threatening. Therapeutic alternatives used to relieve PH and reduce the risk of bleeding include various types of surgical and radiologic vascular procedures. Shunt surgery, which usually results in total diversion of portal blood flow, was introduced several decades ago. The long-term benefits and complications of this therapy have been critically reviewed in the previous edition of this book. New techniques developed during the 1990s. The transjugular intrahepatic porto-systemic stent shunt (TIPS) is now preferred to surgical shunts for treatment of PH in most cirrhotic patients. The splanchnic-to-left-portal vein bypass (Rex shunt), designed for definitive treatment of portal vein obstruction, results in restoration of physiologic intrahepatic portal blood flow. The less invasive techniques of percutaneous endoluminal dilatation or thrombectomy of the portal vein, with or without placement of a stent, have been used mainly as rescue therapies after failed shunts, TIPS or bypasses; a few attempts have been made to use them as a definitive treatment of portal vein obstruction.
Evolution of indications for shunt surgery
Different pathologic conditions cause portal hypertension in children and etiology must be considered when choosing a treatment for PH. In the case of extrahepatic portal obstruction (EHPO), which is either idiopathic or a complication of perinatal thrombosis of the portal vein, liver function is normal or near-normal, and for many years a shunt operation has been considered as the best method of providing lifetime protection against recurrence of bleeding, with an acceptable risk of complications.
The risk for a pathogen to cross the species barrier depends on the rate of efficient contacts between the species. However, contact rates between species have rarely been estimated from observations. Here we estimate contact rates and exposure of chamois Rupicapra rupicapra and Alpine ibex Capra ibex exposed to domestic pasteurellosis and brucellosis carried by sheep or cattle herds summering in mountain pastures. We use field observation data on animal positions treated in a geographic information system (GIS). Comparing 10 pastures, we show that the management of domestic herds influences the risk of inter-species transmission. Exposure to direct transmission of pasteurellosis is high when herds are not guarded nor enclosed, whereas exposure to indirect transmission of brucellosis is increased on epidemiological dangerous points such as salt deposits. Our preliminary results need further investigation, but they underline the importance of both herd management and pathogen transmission mode when the aim is to reduce the risk of contamination of wild populations by a pathogen associated with domestic pathogens.
The artistlike pictures of vortex flows presented here have been produced by the flow itself. The method of this “natural” flow visualization can be described briefly as follows: The working fluid is water mixed with some paste in order to increase the viscosity. Vortex flows are produced by pulling a stick or similar devices through the fluid or by injecting fluid through a nozzle into the working tank.
The flow visualization is performed in the following way: the surface of the fluid at rest is sparkled with oil paint of different colors diluted with some evaporating chemical. After the vortex structures have formed due to wakes or jets, a sheet of white paper is placed on the surface of the working fluid, where the oil color is attached to the paper immediately. The final results are artistlike paintings of vortex flows which exhibit a rich variety of flow structures.
Mixing in regular and chaotic flows
These photographs show the time evolution of two passive tracers in a low Reynolds number two-dimensional timeperiodic flow. The initial condition corresponds to two blobs of dye, green and orange, located below the free surface of a cavity filled with glycerine. The flow is induced by moving the top and bottom walls of the cavity while the other two walls are fixed. In this experiment the top wall moves from left to right and the bottom wall moves from right to left; both velocities are of the form Usin2(2πt/T), with the same U and the same period T, but with a phase shift of 90°.
The simplified perturbation method of Vandenboomgaerde et
al. (2002) is applied to both the
Richtmyer–Meshkov and the Rayleigh–Taylor instabilities.
This theory is devoted to the calculus of the growth rate of the
perturbation of the interface in the weakly nonlinear stage. In the
standard approach, expansions appear to be series in time. We build
accurate approximations by retaining only the terms with the highest
power in time. This simplifies and accelerates the solution. High order
expressions are then easily reachable. For the Richtmyer–Meshkov
instability, multimode configurations become tractable and the
selection mode process can be studied. Inferences for the intermediate
nonlinear regime are also proposed. In particular, a class of
homothetic configurations is inferred; its validity is verified with
numerical simulations even as vortex structures appear at the
interface. This kind of method can also be used for the
Rayleigh–Taylor instability. Some examples are presented.
The construction of short pulse (<200 fs) tunable X-ray
laser sources based on the X-ray free electron laser (XFEL)
concept will be a watershed for plasma-based and warm dense
matter research. These new fourth generation light sources will
have extremely high fields and short wavelengths (∼0.1 nm)
with peak spectral brightnesses 1010 greater than
third generation sources. Further, the high intensity upgrade
of the GSI accelerator facilities will lead to specific energy
depositions up to 200 kJ/g and temperatures between 1 and
10 eV at almost solid-state densities, enabling interesting
experiments in the regime of nonideal plasmas, such as the
evolution of intense ion beams in the interior of a Jovian planet.
Below we discuss several applications: the creation of warm dense
matter (WDM) research, probing of near solid density plasmas, and
laser–plasma spectroscopy of ions in plasmas. The study of
dense plasmas has been severely hampered by the fact that laser-based
methods have been unavailable and these new fourth generation sources
will remove these restrictions.
Electromagnetic emission at the plasma frequency
ωp and its harmonics
nωp has been
studied. Although such emission is well known from very
low density plasmas (electron density of the order of
ne ≈ 108
cm−3) now, for the first time it has
also been observed from a high density plasma (electron
density of the order of ne ≈
1023 cm−3) produced by a
high-intensity femtosecond laser pulse. This radiation is
strongly connected to jets of high energy electrons produced
in such steep gradient plasmas by collective mechanisms, and
probably to nonlinear Langmuir waves in the overdense plasma
region. Theoretical investigations using particle-in-cell
simulations have been made to pinpoint the physical origin
and properties of the emission. Preliminary results show a
very weak scaling of the ωp and
2ωp emission with intensity, which
should provide clues for future theoretical analyses. Although
not the main subject of the present work, also harmonics up
to the 20th of the laser fundamental may have been
observed close to the ωp and
2ωp line emission in the present
experiment (PACS numbers: 52.40.Nk, 42.65.ky, 52.65.-y,
High intensity fs-laser pulses can deliver focused intensities
in the region of 1016–1019
W/cm2. If the laser pulse is focused onto a
solid or gaseous material, a plasma is created. The electrons,
as well as the ions are accelerated in the strong laser
field up to energies in the range of keV to several MeV.
The interaction of the high energy particles with cold
material, that is, the solid target yield of intense X-ray
emission, K-shell—as well as bremsstrahlung-radiation.
The K-shell emission from layered targets is a
useful indicator of the production efficiency, energy distribution,
and transport of hot electrons produced in fs-laser plasmas.
For the diagnosis of laser plasma interaction and its application
as an intense X-ray source, the spatial, temporal and spectral
distribution of K-shell X rays is of fundamental
importance. Focusing crystal spectrographs can be used
to obtain a single shot X-ray spectra of laser plasmas
produced by table top fs-lasers. With a spatial- and spectral-focusing
spectrograph based on a toroidally bent crystal, the emission
region of the hot plasma and Kα-radiation
can be determined. Recording the spectra online by a frontside
illuminated charge-coupled device (CCD) allows alignment
of the crystal spectrograph, as well as the laser beam
focusing leading to different X-ray source sizes. Using
a controlled fs-prepulse, an increase in Kα
radiation could be observed with the diagnostic.
Measurements of calibrated high resolution spectra are compared
with particle-in-cell (PIC) calculations of the laser absorption
and hot electron production postprocessed by a Monte–Carlo
(MC) transport model of electron stopping and Kα X-ray
A prerequisite to studying the specific interactions involved in the persistent transmission of luteoviruses such as the potato leafroll virus (PLRV) is the characterization of both the virus and its vectors. A range of techniques was used to assess genetic differentiation among 27 clones belonging to the Myzus persicae complex (M. persicae (Sulzer), M. antirrhinii (Macchiati) and M. nicotianaeBlackman) and showing different efficiencies in transmitting PLRV isolates. All M. persicae/M. nicotianae clones belonged to one of two karyotypes, both 2n = 12, either normal or carrying an autosomal translocation (A1,3), and all M. antirrhinii clones had 13 or 14 chromosomes. Amplified esterase 4 genes were detected by PCR–REN assay in M. persicae/M. nicotianae taxa, with gene expression being modified by methylation. Similarly, amplified E4 genes were revealed in M. antirrhinii but they all showed unmethylated. Two allozyme and 11 microsatellite loci discriminated 10 different genotypic classes among the 27 clones. Analysis of genetic relatedness between these genotypic classes revealed that M. nicotianae clones were very closely related to M. persicaeclones, whereas the genetic differentiation between M. antirrhinii and M. persicae was greater. The implications of these results for the taxonomic status of these genotypes within the complex, and the transmission of PLRV, are discussed.
Alzheimer's disease raises numerous ethical issues which vary and evolve over the course of the illness. In recognition of the need for ongoing discussion of these issues, the Alzheimer Society of Canada established a Task Force on Ethics in 1995. Through a process of “discourse ethics” and consultation on a national scale, the Task Force produced a series of guidelines dealing with the issues of: communicating the diagnosis, driving, respecting individual choice, quality of life, participation in research, genetic testing, the use of restraints, and end-of-life care. This manuscript presents a summary of these guidelines as well as a summary of the ideas on which they were based. It was the hope of the Society that the publication of these guidelines will serve to facilitate discussion of the ethics of care of those with Alzheimer's disease.