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To determine the effectiveness of ultraviolet (UV) environmental disinfection system on rates of hospital-acquired vancomycin-resistant enterococcus (VRE) and Clostridium difficile.
Using active surveillance and an interrupted time-series design, hospital-acquired acquisition of VRE and C. difficile on a bone marrow transplant (BMT) unit were examined before and after implementation of terminal disinfection with UV on all rooms regardless of isolation status of patients. The main outcomes were hospital-based acquisition measured through (1) active surveillance: admission, weekly, and discharge screening for VRE and toxigenic C. difficile (TCD) and (2) clinical surveillance: incidence of VRE and CDI on the unit.
Bone marrow transplant unit at a tertiary-care cancer center.
Stem cell transplant (SCT) recipients.
Terminal disinfection of all rooms with UV regardless of isolation status of patients.
During the 20-month study period, 579 patients had 704 admissions to the BMT unit, and 2,160 surveillance tests were performed. No change in level or trend in the incidence of VRE (trend incidence rate ratio [IRR], 0.96; 95% confidence interval [CI], 0.81–1.14; level IRR, 1.34; 95% CI, 0.37–1.18) or C. difficile (trend IRR, 1.08; 95% CI, 0.89–1.31; level IRR, 0.51; 95% CI, 0.13–2.11) was observed after the intervention.
Utilization of UV disinfection to supplement routine terminal cleaning of rooms was not effective in reducing hospital-acquired VRE and C. difficile among SCT recipients.
Objectives: Studies suggest that impairments in some of the same domains of cognition occur in different neuropsychiatric conditions, including those known to share genetic liability. Yet, direct, multi-disorder cognitive comparisons are limited, and it remains unclear whether overlapping deficits are due to comorbidity. We aimed to extend the literature by examining cognition across different neuropsychiatric conditions and addressing comorbidity. Methods: Subjects were 486 youth consecutively referred for neuropsychiatric evaluation and enrolled in the Longitudinal Study of Genetic Influences on Cognition. First, we assessed general ability, reaction time variability (RTV), and aspects of executive functions (EFs) in youth with non-comorbid forms of attention-deficit/hyperactivity disorder (ADHD), mood disorders and autism spectrum disorder (ASD), as well as in youth with psychosis. Second, we determined the impact of comorbid ADHD on cognition in youth with ASD and mood disorders. Results: For EFs (working memory, inhibition, and shifting/ flexibility), we observed weaknesses in all diagnostic groups when participants’ own ability was the referent. Decrements were subtle in relation to published normative data. For RTV, weaknesses emerged in youth with ADHD and mood disorders, but trend-level results could not rule out decrements in other conditions. Comorbidity with ADHD did not impact the pattern of weaknesses for youth with ASD or mood disorders but increased the magnitude of the decrement in those with mood disorders. Conclusions: Youth with ADHD, mood disorders, ASD, and psychosis show EF weaknesses that are not due to comorbidity. Whether such cognitive difficulties reflect genetic liability shared among these conditions requires further study. (JINS, 2018, 24, 91–103)
To determine whether implementation of a multifaceted intervention would significantly reduce the incidence of central line–associated bloodstream infections.
Prospective cohort collaborative.
SETTING AND PARTICIPANTS
Intensive care units of the Abu Dhabi Health Services Company hospitals in the Emirate of Abu Dhabi.
A bundled intervention consisting of 3 components was implemented as part of the program. It consisted of a multifaceted approach that targeted clinician use of evidence-based infection prevention recommendations, tools that supported the identification of local barriers to these practices, and implementation ideas to help ensure patients received the practices. Comprehensive unit-based safety teams were created to improve safety culture and teamwork. Finally, the measurement and feedback of monthly infection rate data to safety teams, senior leaders, and staff in participating intensive care units was encouraged. The main outcome measure was the quarterly rate of central line–associated bloodstream infections.
Eighteen intensive care units from 7 hospitals in Abu Dhabi implemented the program and achieved an overall 38% reduction in their central line–associated bloodstream infection rate, adjusted at the hospital and unit level. The number of units with a quarterly central line–associated bloodstream infection rate of less than 1 infection per 1,000 catheter-days increased by almost 40% between the baseline and postintervention periods.
A significant reduction in the global morbidity and mortality associated with central line–associated bloodstream infections is possible across intensive care units in disparate settings using a multifaceted intervention.
Infect. Control Hosp. Epidemiol. 2015;36(7):816–822
Fibrin hydrogels are an exciting platform for cell-based therapies, as they contain necessary cues for adhesion, can be remodeled by entrapped cells, and the biophysical properties can be modified with a plethora of strategies. Furthermore, fibrin acts as a provisional matrix in vivo for tissue regeneration. While the majority of studies seek to manipulate fibrin gel properties by changing the concentration of clotting proteins, these studies highlight our capacity to change bulk stiffness and fiber properties by supplementing the solutions with sodium chloride (NaCl). Physical properties including fiber thickness, porosity, compressive modulus, and fluid uptake capacity were dependent on NaCl content, with gels containing 2.60% (w/v) NaCl exhibiting compressive moduli threefold higher than gels without NaCl. These material properties, in turn, affected the gel morphology along with the osteogenic and pro-angiogenic response of entrapped mesenchymal stem/stromal cells (MSCs). The osteoconductivity of fibrin gels can be enhanced by inclusion of apatite-coated polymer substrata to nucleate mineral, while the efficacy of engineered fibrin gels to simultaneously deploy small molecules with cells to enhance endogenous angiogenic potential has been demonstrated. Collectively, these data demonstrate the broad capacity of engineered fibrin gels to regulate function of entrapped cells for use in tissue engineering and regenerative medicine.
To evaluate the impact of postprescription review of broad-spectrum antimicrobial (study-ABX) agents on rates of antimicrobial use.
Quasi-experimental before-after study.
Five academic medical centers.
Adults receiving at least 48 hours of study-ABX.
The baseline, intervention, and follow-up periods were 6 months each in 2 units at each of 5 sites. Adults receiving at least 48 hours of study-ABX entered the cohort as case-patients. During the intervention, infectious-diseases physicians reviewed the cases after 48 hours of study-ABX. The provider was contacted with alternative recommendations if antimicrobial use was considered to be unjustified on the basis of predetermined criteria. Acceptance rates were assessed 48 hours later. The primary outcome measure was days of study-ABX per 1,000 study-patient-days in the baseline and intervention periods.
There were 1,265 patients in the baseline period and 1,163 patients in the intervention period. Study-ABX use decreased significantly during the intervention period at 2 sites: from 574.4 to 533.8 study-ABX days/1,000 patient-days (incidence rate ratio [IRR], 0.93; 95% confidence interval [CI], 0.88-0.97; P = .002) at hospital В and from 615.6 to 514.4 study-ABX days/1,000 patient-days (IRR, 0.83; 95% CI, 0.79-0.88; P < .001) at hospital D. Both had established antimicrobial stewardship programs (ASP). Study-ABX use increased at 2 sites and stayed the same at 1 site. At all institutions combined, 390 of 1,429 (27.3%) study-ABX courses were assessed as unjustified; recommendations to modify or stop therapy were accepted for 260 (66.7%) of these courses.
Postprescription review of study-ABX decreased antimicrobial utilization in some of the study hospitals and may be more effective when performed as part of an established ASP.
Recent surveillance from US hospitals shows that more than 99.5% of vancomycin-resistant enterococci (VRE) isolates remain susceptible to daptomycin. This report describes emergence of daptomycin-resistant VRE at a major cancer center. The percentage of patients with daptomycin-resistant VRE bacteremia increased from 3.4% in 2007 to 15.2% in 2009 (P = .03). Without susceptibility data, empiric daptomycin therapy for VRE infections should be used with caution.
The results of the experimental study of CoX/Pd multilayer based recording layers for perpendicular recording media are presented. The perpendicular magnetic recording media with multilayer recording layers and high moment soft underlayers were deposited by magnetron sputtering. It is shown how a favorable microstructure of the multilayer films can be achieved by the use of the appropriate buffer layers. The effects of boron addition to the cobalt layer in a multilayer recording layer is described. The feasibility of the aging process that leads to the reduced exchange coupling in the multilayer recording layer, is demonstrated. It is shown that boron addition to the cobalt layer accelerates the aging process.
The extent of damage recovery by N2 plasma treatment of previously damaged n- and p-GaN has been examined using current-voltage (I-V) characteristics from Schottky diodes. There are two contributions to the observed improvement in the I-V characteristics, namely a simple annealing effect and also a chemical effect from reactive nitrogen. However the N2 plasma treatment does not fully restore the initial electrical properties of the near-surface region.
Previous work has recently employed x-ray interferometry for the unique determination of the profile structures of ultrathin Langmuir-Blodgett multilayer films of Cd-arachidate and of tethered protein monolayers on the surface of Ge/Si multilayer substrates [1, 2]. These studies utilized the inorganic substrate as the reference structure for the interferometrie phasing of the meridional x-ray diffraction I (Qxy=0A-1, QZ) from the inorganic-organic composite structure. The substrates, fabricated by magnetron sputtering, contained only broad profile features (≥20 A), thereby limiting the spatial resolution of the organic profile structures so-determined. Molecular beam epitaxy (MBE) permits the fabrication of the multilayer reference structure with profile features as narrow as a single atomic monolayer, thereby providing delta-function-like features in the reference structure. The reference structure can then be tailored such that the autocorrelation function of the inorganic-organic composite profile structure [obtained by a Fourier transform of its meridional diffraction I (Qxy=0A-1, Qz) data without phase information] contains only the organic profile structure itself over a particular range of the profile coordinate z. This approach for uniquely determining the unknown profile structure of the organic overlayer is x-ray holography by analogy to simple off-axis holography with much longer wavelength radiation. We have initially utilized MBE fabricated Ge/Si multilayer substrates of the type N(Ge2Si30), e.g., for N=2 or 3 superlattice unit cells, each containing two Ge monolayers and thirty Si monolayers, to thereby determine the profile structures of four different organic overlayers, namely a) self-assembled alkylsiloxane monolayers, b) Langmuir-Blodgett cadmium alkylcarboxylate monolayers, c) a Langmuir-Blodgett Cd-arachidate head-to-head bilayer deposited on a)-above and, d) a covalently tethered protein monolayer.
The antiferromagnctic FeMn thin film has been used to stabilize the domains in NiFe films by exchange-coupling, thus eliminating the Barkhauscn noise in magnetoresistive sensor designs. T'he strength of this exchange-coupling is highly dependent on the interfacial structure, as well as the interfacial composition of this NiFe/FeMn thin film couple. We have conducted isothermal, as well as isochronal anneals of NiFe/FeMn thin film couples, and monitored their magnetic properties, in particular the strength of their exchange-coupling. The strength of exchange-coupling, measured by the shift of the B-H loop obtained from a hysteresis loop tracer, increased monotonically with annealing time for isothermal anneals between 200 and 300 °C. At higher temperatures (up to 500°C), the interdiffusion between the two layers is so extensive that the NiFe layer loses its sort-magnetic properties and the coupling strength is degraded. Composition depth-profiling by scanning Auger analysis was conducted to study the interdiffusion profiles of the annealed samples. Cross-section transmission electron microscopy (XTEM) was used to study the microstructure, crystallography, and composition of these thin films after annealing. Micro-beam composition analysis was also carried out and the compositional profile obtained was compared to the Auger depth-profile results. Transmitted electron diffraction using selected area electron diffraction (SAED) and elongated probe micro-diffraction (EPMD) of XTEM samples was used to study the crystallography of these films.
The domain state model for exchange bias consists of a ferromagnetic layer exchange coupled to an antiferromagnetic layer. In order to model a certain degree of disorder within the bulk of the antiferromagnet, the latter is diluted throughout its volume. Extensive Monte Carlo simulations of the model were performed in the past. Exchange bias is observed as a result of a domain state in the antiferromagnetic layer which develops during the initial field cooling, carrying a remanent domains state magnetization which is partly irreversible during hysteresis. A variety of typical effects associated with exchange bias like, e. g., its dependence on dilution, positive bias, temperature and time dependences as well as the dependence on the thickness of the antiferromagnetic layer can be explained within this model.