Currently, contact precautions are recommended for patients colonized or infected with extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-PE). Recent studies have challenged this ...strategy. This study aimed to assess the rate of ESBL-PE faecal carriage among hospitalized patients according to type of hospital ward, and to identify risk factors associated with carriage.
A point prevalence study was conducted in five different types of hospital ward medical, surgical, intensive care unit (ICU), after care and rehabilitation, and geriatric in eight French hospitals. All patients included in the study provided a fresh stool sample.
In total, 554 patients were included in the study, with a median age of 73 years (range 60–82 years). The overall faecal carriage rate of ESBL-PE was 17.7%. The most frequently encountered species among ESBL-PE was Escherichia coli (71.4%), followed by Klebsiella pneumoniae (14.3%). Risk factors associated with ESBL-PE faecal carriage on univariate analysis were: living in the Paris region (P<0.01) and hospitalization on a geriatric ward (P<0.01). Interestingly, the cumulative duration of hospital stay before screening was not associated with a significantly higher prevalence of ESBL-PE carriage, regardless of ward type. The ESBL-PE colonization rate was much higher for patients hospitalized on geriatric wards (28.1%) and ICUs (21.7%) compared with those for patients hospitalized on surgical wards (14.8%), medical wards (12.8%) or aftercare and rehabilitation (11.2%).
The overall prevalence of ESBL-PE faecal carriage was 17.7%, with only 21% of patients identified previously as carriers. The delay between admission and screening was not associated with an increase in ESBL-PE faecal carriage.
La confirmation de l’origine fongique d’une onychopathie par un examen mycologique est essentielle. Pour ce faire, en parallèle à la mise en culture des échantillons biologiques, la réalisation d’un ...examen direct sensible et informatif des fragments d’ongle et de matière sous-unguéale est primordiale. Parmi les techniques d’examen direct proposées, et inspirées de la reconnaissance comme référence par les histo-pathologistes de la réaction « acide périodique – réactif de Schiff » pour colorer les parois fongiques, la technique simplifiée de coloration PAS selon Hotchkiss et MacManus est une technique de choix. Simple à mettre en œuvre et très sensible, elle permet de confirmer d’emblée et formellement le diagnostic d’onychomycose, d’évoquer le type de champignon responsable (levure, dermatophyte, hyphomycète opportuniste) et de suspecter une éventuelle implication multiple.
Confirmation of fungal origin of onychopathy by mycological examination is essential. For that purpose, in parallel to the cultivation of biological samples, achieving a sensitive and informative direct examination of nail fragments and subungual material is primordial. Among the direct examination techniques, and inspired from a technique of reference in histo-pathology (the “periodic acid-Schiff reagent” reaction), the simplified technique of PAS staining according to Hotchkiss and MacManus is the technique of choice. Easy to implement and very sensitive, it can immediately and formally confirm the diagnosis of onychomycosis, mention the type of fungus (yeast, dermatophyte, Hyphomycete opportunistic) and suspect a possible multiple involvement.
Magnesium hydride owns the largest share of publications on solid materials for hydrogen storage. The “Magnesium group” of international experts contributing to IEA Task 32 “Hydrogen Based Energy ...Storage” recently published two review papers presenting the activities of the group focused on magnesium hydride based materials and on Mg based compounds for hydrogen and energy storage. This review article not only overviews the latest activities on both fundamental aspects of Mg-based hydrides and their applications, but also presents a historic overview on the topic and outlines projected future developments. Particular attention is paid to the theoretical and experimental studies of Mg-H system at extreme pressures, kinetics and thermodynamics of the systems based on MgH2, nanostructuring, new Mg-based compounds and novel composites, and catalysis in the Mg based H storage systems. Finally, thermal energy storage and upscaled H storage systems accommodating MgH2 are presented.
•Historical overview of Mg-based hydrides.•Nanostructured Mg-based H storage materials prepared by mechanical alloying and reactive ball milling.•Thermodynamics and kinetics for Mg-based hydrides.•Catalysis in Mg-H system.•Mg-H system at high pressures: theoretical and experimental studies.
Laser wakefield accelerators promise to revolutionize many areas of accelerator science. However, one of the greatest challenges to their widespread adoption is the difficulty in control and ...optimization of the accelerator outputs due to coupling between input parameters and the dynamic evolution of the accelerating structure. Here, we use machine learning techniques to automate a 100 MeV-scale accelerator, which optimized its outputs by simultaneously varying up to six parameters including the spectral and spatial phase of the laser and the plasma density and length. Most notably, the model built by the algorithm enabled optimization of the laser evolution that might otherwise have been missed in single-variable scans. Subtle tuning of the laser pulse shape caused an 80% increase in electron beam charge, despite the pulse length changing by just 1%.
We describe a scheme for controlling electron injection into the quasilinear wakefield driven by a guided drive pulse via ionization of a dopant species by a collinear injection laser pulse with a ...short Rayleigh range. The scheme is analyzed by particle-in-cell simulations which show controlled injection and acceleration of electrons to an energy of 370 MeV, a relative energy spread of 2%, and a normalized transverse emittance of 2.0 μm.
Microscopy is the reference standard for routine laboratory diagnosis in faecal parasitology but there is growing interest in alternative methods to overcome the limitations of microscopic ...examination, which is time-consuming and highly dependent on an operator's skills and expertise. Compared with microscopy, DNA detection by PCR is simple and can offer a better turnaround time. However, PCR performances remain difficult to assess as most studies have been conducted on a limited number of positive clinical samples and used in-house PCR methods. Our aim was to evaluate a new multiplex PCR assay (G-DiaParaTrio; Diagenode Diagnostics), targeting Giardia intestinalis, Cryptosporidium parvum/Cryptosporidium hominis and Entamoeba histolytica. To minimize the turnaround time, PCR was coupled with automated DNA extraction (QiaSymphony; Qiagen). The PCR assay was evaluated using a reference panel of 185 samples established by routine microscopic examination using a standardized protocol including Ziehl–Neelsen staining and adhesin detection by ELISA (E. histolytica II; TechLab). This panel, collected from 12 French parasitology laboratories, included 135 positive samples for G. intestinalis (n = 38), C. parvum/C. hominis (n = 26), E. histolytica (n = 5), 21 other gastrointestinal parasites, together with 50 negative samples. In all, the G-DiaParaTrio multiplex PCR assay identified 38 G. intestinalis, 25 C. parvum/C. hominis and five E. histolytica leading to sensitivity/specificity of 92%/100%, 96%/100% and 100%/100% for G. intestinalis, C. parvum/C. hominis and E. histolytica, respectively. This new multiplex PCR assay offers fast and reliable results, similar to microscopy-driven diagnosis for the detection of these gastrointestinal protozoa, allowing its implementation in routine clinical practice.
Laser-wakefield accelerators (LWFAs) are high acceleration-gradient plasma-based particle accelerators capable of producing ultra-relativistic electron beams. Within the strong focusing fields of the ...wakefield, accelerated electrons undergo betatron oscillations, emitting a bright pulse of X-rays with a micrometer-scale source size that may be used for imaging applications. Non-destructive X-ray phase contrast imaging and tomography of heterogeneous materials can provide insight into their processing, structure, and performance. To demonstrate the imaging capability of X-rays from an LWFA we have examined an irregular eutectic in the aluminum-silicon (Al-Si) system. The lamellar spacing of the Al-Si eutectic microstructure is on the order of a few micrometers, thus requiring high spatial resolution. We present comparisons between the sharpness and spatial resolution in phase contrast images of this eutectic alloy obtained via X-ray phase contrast imaging at the Swiss Light Source (SLS) synchrotron and X-ray projection microscopy via an LWFA source. An upper bound on the resolving power of 2.7 ± 0.3 μm of the LWFA source in this experiment was measured. These results indicate that betatron X-rays from laser wakefield acceleration can provide an alternative to conventional synchrotron sources for high resolution imaging of eutectics and, more broadly, complex microstructures.
We describe a simple scheme, truncated-channel injection, to inject electrons directly into the wakefield driven by a high-intensity laser pulse guided in an all-optical plasma channel. We use this ...approach to generate dark-current-free 1.2 GeV, 4.5% relative energy spread electron bunches with 120 TW laser pulses guided in a 110 mm-long hydrodynamic optical-field-ionized plasma channel. Our experiments and particle-in-cell simulations show that high-quality electron bunches were only obtained when the drive pulse was closely aligned with the channel axis, and was focused close to the density down ramp formed at the channel entrance. Start-to-end simulations of the channel formation, and electron injection and acceleration show that increasing the channel length to 410 mm would yield 3.65 GeV bunches, with a slice energy spread ∼5×10^{-4}.
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