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The preventable proportion of healthcare-associated infections (HAIs) may decrease over time as standards of care improve. We aimed to assess the proportion of HAIs prevented by multifaceted infection control interventions in different economic settings.
In this systematic review and meta-analysis, we searched OVID Medline, EMBASE, CINAHL, PubMed, and The Cochrane Library for studies published between 2005 and 2016 assessing multifaceted interventions to reduce catheter-associated urinary tract infections (CAUTIs), central-line–associated bloodstream infections (CLABSIs), surgical site infections (SSIs), ventilator-associated pneumonia (VAP), and hospital-acquired pneumonia not associated with mechanical ventilation (HAP) in acute-care or long-term care settings. For studies reporting raw rates, we extracted data and calculated the natural log of the risk ratio and variance to obtain pooled risk ratio estimates.
Of the 5,226 articles identified by our search, 144 studies were included in the final analysis. Pooled incidence rate ratios associated with multifaceted interventions were 0.543 (95% confidence interval [CI], 0.445–0.662) for CAUTI, 0.459 (95% CI, 0.381–0.554) for CLABSI, and 0.553 (95% CI, 0.465–0.657) for VAP. The pooled rate ratio was 0.461 (95% CI, 0.389–0.546) for interventions aiming at SSI reduction, and for VAP reduction initiatives, the pooled rate ratios were 0.611 (95% CI, 0.414–0.900) for before-and-after studies and 0.509 (95% CI, 0.277–0.937) for randomized controlled trials. Reductions in infection rates were independent of the economic status of the study country. The risk of bias was high in 143 of 144 studies (99.3%).
Published evidence suggests a sustained potential for the significant reduction of HAI rates in the range of 35%–55% associated with multifaceted interventions irrespective of a country’s income level.
Preventing ventilator-associated pneumonia (VAP) is an important goal for intensive care units (ICUs). We aimed to identify the optimal behavior leverage to improve VAP prevention protocol adherence.
Mixed-method study using adherence measurements to assess 4 VAP prevention measures and qualitative analysis of semi-structured focus group interviews with frontline healthcare practitioners (HCPs).
The 6 ICUs in the 900-bed University Hospital Zurich in Zurich, Switzerland.
Patients and participants
Adherence to VAP prevention measures were assessed in patients with a device for invasive ventilation (ie, endotracheal tube, tracheostomy tube). Participants in focus group interviews included a convenience samples of ICU nurses and physicians.
Between February 2015 and July 2017, we measured adherence to 4 protocols: bed elevation showed adherence at 27% (95% confidence intervals [CI], 23%–31%); oral care at 41% (95% CI, 36%–45%); sedation interruption at 81% (95% CI, 74%–85%); and subglottic suctioning at 88% (95% CI, 83%–92%). Interviews were analyzed first inductively according a grounded theory approach then deductively against the behavior change wheel (BCW) framework. Main behavioral facilitators belonged to the BCW component ‘reflective motivation’ (ie, perceived seriousness of VAP and self-efficacy to prevent VAP). The main barriers belonged to ‘physical capability’ (ie, lack of equipment and staffing and side-effects of prevention measures). Furthermore, 2 primarily technical approaches (ie, ‘restructuring environment’ and ‘enabling HCP’) emerged as means to overcome these barriers.
Our findings suggest that technical, rather than education-based, solutions should be promoted to improve VAP prevention. This theory-informed mixed-method approach is an effective means of guiding infection prevention efforts.
An outbreak of invasive Mycobacterium chimaera infections associated with heater-cooler devices (HCDs) has now affected patients in several countries on different continents. Clinical infections are characterized by delayed diagnosis, inadequate treatment response to antimicrobial agents, and poor prognosis. Outbreak investigators found M. chimaera in HCD water circuits and air samples while HCDs were running, suggesting that transmission from the HCD to the surgical site occurs via the airborne route. New HCDs at the manufacturing site were also contaminated with M. chimaera, and recent whole-genome sequencing data suggest a point source. Some guidance on screening for M. chimaera colonization in HCD water and exhaust air is available. In contrast, reliable disinfection procedures are not well described, and it is not yet known whether eradication of M. chimaera from a contaminated HCD can be achieved. Meanwhile, strict separation of the HCD from operating room air is necessary to ensure patient safety, and these efforts may require engineering solutions. While our understanding of the causes and the extent of the M. chimaera outbreak is growing, several aspects of patient management, device handling, and risk mitigation still require clarification.
Based on new spectra spanning wavelengths from 0.8 to 2.4μm, we study the properties of bright near-IR clusters in M82. We focus on age and extinction, which are critical parameters when one uses dynamical masses to constrain the stellar IMF. The modelling of red supergiant evolution by various authors leads to very significant differences in synthetic cluster spectra. Near-IR fluxes alone therefore do not rule out a normal IMF for cluster F, previously found to be deficient in low mass stars. Combined optical and near-IR studies are being undertaken.
The Dawson seriation of Nasca ceramics has long been assumed to be an accurate marker of temporal changes in the prehispanic south coast of Peru. We test this assumption by directly dating a sample of sherds using Optically Stimulated Luminescence (OSL). Our results suggest that while some phases of the seriation are valid chronological markers, others appear to be the result of factors other than time. We discuss the implications of these results and call for additional studies of ceramics using luminescence dating
Advancement of ion acceleration by intense laser pulses is studied with ultra-thin nanometer-thick diamond like carbon and micrometer-thick Titanium target foils. Both investigations aim at optimizing the electron density distribution which is the key for efficient laser driven ion acceleration. While recently found maximum ion energies achieved with ultra-thin foils mark record values micrometer thick foils are flexible in terms of atomic constituents. Electron recirculation is one prerequisite for the validity of a very simple model that can approximate the dependence of ion energies of nanometer-thick targets when all electrons of the irradiated target area interact coherently with the laser pulse and Coherent Acceleration of Ions by Laser pulses (CAIL) becomes dominant. Complementary experiments, an analytical model and particle in cell computer simulations show, that with regard to ultra-short laser pulses (duration ~45 fs at intensities up to 5 × 1019 W/cm2) and a micrometer-thick target foil with higher atomic number a close to linear increase of ion energies manifests in a certain range of laser intensities.
In this paper we report on an experimental study of high harmonic radiation generated in nanometer-scale foil targets irradiated under normal incidence. The experiments constitute the first unambiguous observation of odd-numbered relativistic harmonics generated by the v × B component of the Lorentz force verifying a long predicted property of solid target harmonics. Simultaneously the observed harmonic spectra allow in-situ extraction of the target density in an experimental scenario which is of utmost interest for applications such as ion acceleration by the radiation pressure of an ultraintense laser.
Dès la concentration initiale de 125 µg Cu/l, le sulfate de cuivre en eau dure affecte la capacité des larves d'Hydropsyche à construire un filet. La première irrégularité apparente est le nombre élevé d'interruptions des fils. A concentration plus élevée, le nombre de mailles par filet diminue.
Une anomalie typique de l'action toxique du cuivre est le dépôt de fils sous la forme d'amas de soie. La symétrie et la régularité des mailles dans la zone de capture n'est que faiblement affectée par le cuivre. Ceci contraste avec les effets d'un carbamate, insecticide étudié antérieurement.
La localisation première de l'action du cuivre paraît être la glande à soie et non le système nerveux comme cela est le cas avec l'insecticide précité.
Les résultats obtenus en laboratoire confirment les observations de terrain. Les concentrations affectant sévèrement la construction des filets empêchent les larves de se développer dans la nature. Le test Hydropsyche n'exige que de courtes périodes de temps et un équipement simple ; il fournit cependant une information sur des effets à long terme.
Mental health is an important aspect of public health after a disaster. This article describes what is known and what remains to be learned regarding the mental health impact of the January 12, 2010, earthquake in Haiti. Public health surveillance efforts in Haiti and the United States in the first 2 months after the earthquake are described. Challenges in clinical assessment and public health surveillance are explored. Potential implications for survivors and public health officials are considered.
(Disaster Med Public Health Preparedness. 2011;5:154–157)
As a behavioral addiction with clinical and phenomenological similarities to substance addiction, recreational and pathological gambling represent models for studying the neurobiology of addiction, without the confounding deleterious brain effects which may occur from chronic substance abuse.
A community sample of individuals aged 18–65 years who gamble was solicited through newspaper advertising. Subjects were grouped a priori into three groups (no-risk, at-risk, and pathological gamblers) based on a diagnostic interview. All subjects underwent a psychiatric clinical interview and neurocognitive tests assessing motor impulsivity and cognitive flexibility. Subjects with a current axis I disorder, history of brain injury/trauma, or implementation or dose changes of psychoactive medication within 6 weeks of study enrollment were excluded.
A total of 135 no-risk, 69 at-risk and 46 pathological gambling subjects were assessed. Pathological gamblers were significantly older, and exhibited significant deficiencies in motor impulse control (stop-signal reaction times), response speed (median ‘go’ trial response latency) and cognitive flexibility [total intra-dimensional/extra-dimensional (IDED) errors] versus controls. The finding of impaired impulse control and cognitive flexibility was robust in an age-matched subgroup analysis of pathological gamblers. The no-risk and at-risk gambling groups did not significantly differ from each other on task performance.
Impaired response inhibition and cognitive flexibility exist in people with pathological gambling compared with no-risk and at-risk gamblers. The early identification of such illness in adolescence or young adulthood may aid in the prevention of addiction onset of such disabling disorders.
The oxidation-reduction equilibria of selected multivalent elements in an alkali borosilicate glass melt (Savannah River Laboratory frit #131) were measured as a function of the imposed oxygen fugacity over the temperature range from 950°C to 1350°C. Redox constraints on the processing of high-level nuclear waste into the glass melt require that the prevailing oxygen fugacity be about 10−5 to 10−12 Zatm at 950°C, about 10−2 to 10−9 atm at 1150°C, and about 100 to 10−7 atm at 1350°C. Such conditions circumvent foaming under oxidizing situations and metal/sulfide precipitation if the system becomes too reducing. The defined oxygen fugacity ranges correspond to the previously prescribed range of 0.1 to 0.5 for the [Fe2+]/[Fe3+] ratio in the resulting glass, independent of the processing temperature from 950°C to 1350°C.
Water uptake and conduction have been studied in SrYb0.05Ce0.95O3-δ, a composition known to conduct protons, oxygen ions, and electrons, depending on temperature and environment. Water uptake kinetics evaluated by thermogravimetry occurred in two distinct stages: a rapid, initial weight gain (0.39±0.09 eV, attributed to grain boundary and near surface hydration) followed by a much slower uptake (2.8±0.4 eV, attributed to hydration of the bulk grains). From cyclic voltammetry and mass spectrometry measurements for a cell exposed to asymmetric conditions, currents and activation energies for electronic, oxygen ion, and proton conduction were determined. The activation energy for electronic conduction, 0.90±0.09 eV, is believed to be artificially high due to the increase in electron carrier concentration with increased temperature. The activation energy for oxygen ion conduction (0.97±0.10 eV) agrees well with other oxygen conductors. Proton conduction appeared to follow two different mechanisms: a low temperature process characterized by an activation energy of 0.42±0.04 eV, and a high temperature process, characterized by an activation energy of 1.38±0.13 eV. A possible explanation is that proton conduction at low temperatures is dominated by grain boundaries and is dominated by bulk conduction at higher temperatures.
A lattice-gas model is presented, where ions are diffusing in an energy landscape due to immobile, randomly placed counterions. All Coulombic interactions are taken into account.By Monte Carlo simulations we obtain the ac-conductivity, which shows strong dispersion in the form of power-laws. In a separate study we investigate a restricted model, where long-range diffusion is suppressed. These calculations suggest that the response at high frequencies can be interpreted in terms of highly correlated, local motions of dipolar character. Conductivity exponents n1 near unity or even exceeding unity arefound in that regime. We discuss the relationship of these results to experiments on ionic transport in alkali-doped network glasses.
Research into the growth of high-quality single crystal thin films of high transition temperature (Tc) superconductors have stimulated interest in other perovskite metal oxides with a variety of physical properties.1 Thin films of perovskite materials are among the major focal research areas for optical, sensor, electronic, and superconducting applications.1 Two lanthanumbased oxygen/electronic conducting perovskite oxides of particular interest for high temperature fuel cell electrodes and interconnects and for other electrochemical applications such as oxygen separation devices are Lal-xSrxMnO3-y and Lal-xSrxCoO3-y. The La-based perovskites are valuable for these technologies because they reduce interfacial resistances by eliminating the need for a three phase contact area (gas, metal electrode, electrolyte).2 In addition, these oxides may also serve a valuable role as novel catalysts or catalytic supports; however, little is known about what catalytic properties they may possess.
The growth of high-quality, pin-hole free, ytrrium doped ZrO2 thin films is of great interest for a variety of electrochemical applications such as fuel cells and oxygen gas separation devices. In the work, we have grown polycrystalline thin films of ytrrium doped ZrO2 on thick porous Al2O3 substrates in multilayer La1-xSrxMEO3/YSZ/La1-xSrxMEO3 (ME = Mn, Co) configurations using a combination of single-target RF magnetron sputtering and electron beam physical vapor deposition techniques. The structure and morphology of these films have been studied using X-ray diffraction, and Scanning Electron Microscopy techniques. The ionic conductivity of the thin films has been measured using AC impedance analysis.
Because of the procedures associated with the deconvolution of the data present in an EXAFS spectrum, the experimental XAFS spectra also include both the edge and XANES regions. It is possible to obtain additional structural and chemical information from the data associated with these regions of the XAFS spectrum and in this work we have re-examined the XAFS spectra for a series of polymer electrolytes. These spectra were originally recorded for EXAFS analysis. The XANES spectra for PEOn:CaBr2 electrolytes confirm that the behaviour of calcium polymer electrolytes appears to be very different from that of other divalent based electrolytes. We have also examined the edge features for PEO8:NiBr2 samples which were subject to different thermal histories and evidence for phase separation is presented.
Lithium can be intercalated into a variety of materials using aqueous electrochemical methods, provided that certain criteria are met. The materials must be stable in concentrated Li+ aqueous solution and Li intercalation must take priority over hydrogen intercalation. We use X-ray and neutron diffraction, as well as electrochemical methods to investigate if lithium or hydrogen is intercalated into certain hosts. For example, spinel Li2Mn2O4 can be made from spinel LiMn204 by intercalating one Li per mole in an electrochemical cell with 1 M LiOH electrolyte. If the electrochemical reduction is carried out further, beyond one electron per mole, Mn(OH)2 is then formed, as we prove using neutron diffraction. By carefully selecting electrode materials and electrolyte composition it is possible to make rechargeable lithium-ion cells with aqueous electrolytes. For example, LiMn204/γ-Li0.36MnO2 can be selected as an electrode couple, and5 M LiNO3 in water as an electrolyte to make lithium-ion cells with aqueous electrolytes.
In a randomly oriented polycrystalline ionically conducting material the total conductivity is reduced by the lengthening of the effective conduction pathway which is determined by the microstructure. It is, therefore, desirable to develop a better understanding of the relationship between the conductivity and the microstructure of the ceramic material.
This work focused on the quantification of the various contributions to the overall conductivity. Na-β” alumina ceramics with different microstructures but the same chemical composition were used as samples. Conductivity data were obtained by impedance spectroscopy measurements (IS) carried out in a temperature range from 350 to -30 °C at frequencies from 1 Hz to 500 KHz. An attempt has been made to calculate distinct geometric factors for the specific values of the grain and grain boundary contribution. These were inferred from the sample geometry, Laser Scanning Microscope (LSM) pictures, microstructural observations by image analysis, Transmission Electron Microscope (TEM) pictures, and considerations of the current pathways in the anisotropically conducting ceramic.