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Hand hygiene is the primary measure for reducing nosocomial infections based on 7 steps recommended by the WHO. The aim of this study was to assess the duration and the quality of hand hygiene before and after simulation-based training (SBT).
The study took place in a University Hospital Pediatric Department among its residents and nurses. In assessment A, 10 hand-rubbing procedures per participant during a work day were scored by observers using a validated, anatomically based assessment scale. Two weeks later, all participants received a didactic course and SBT, followed 1 month later by assessment B, observation of 10 hand-rubbing procedures. Assessments were performed by 2 independent observers. Before-and-after testing was used to evaluate the demonstration of theoretical knowledge.
In total, 22 participants were included, for whom 438 hand hygiene procedures were assessed: 218 for assessment A and 220 for assessment B. The duration of hand rubbing increased from 31.16 seconds in assessment A to 35.75 seconds in assessment B (P=.04). In assessment A, participants averaged 6.33 steps, and in assessment B, participants averaged 6.03 steps (difference not significant). Significant improvement in scores was observed between assessments A and B, except for the dorsal side of the right hand. The wrist and interdigital areas were the least-cleaned zones. A difference between assessments A and B was observed for nail varnish (P=.003) but not for long nails or jewelry. Theoretical scores increased from 2.83 to 4.29 (scale of 0–5; P<.001).
This study revealed that an optimal number of steps were performed during hand-rubbing procedures and that SBT improved the duration and quality of hand hygiene, except for the dorsal right side. Emphasis should be placed on the specific hand areas that remained unclean after regular hand-rubbing procedures.
An anatomically based assessment scale of handwashing quality with alcohol-based hand rub was designed. Contents of the scale divided each hand into 40 zones. Psychometric measurements were studied in 30 participants (120 hand sides). The scale was both valid (Cronbach α: 0·83 dorsal side and 0·73 palmar side) and reproducible (linear regression R2, 0·91; intraclass correlation coefficient, 0·99).
In September 2016, the annual meeting of the International Union for Quaternary Research’s Loess and Pedostratigraphy Focus Group, traditionally referred to as a LoessFest, met in Eau Claire, Wisconsin, USA. The 2016 LoessFest focused on “thin” loess deposits and loess transportation surfaces. This LoessFest included 75 registered participants from 10 countries. Almost half of the participants were from outside the United States, and 18 of the participants were students. This review is the introduction to the special issue for Quaternary Research that originated from presentations and discussions at the 2016 LoessFest. This introduction highlights current understanding and ongoing work on loess in various regions of the world and provides brief summaries of some of the current approaches/strategies used to study loess deposits.
The cold-based termini of polythermal glaciers are usually assumed to adhere strongly to an immobile substrate and thereby supply significant resistance to the flow of warm-based ice up-glacier. This compressive environment is commonly thought to uplift basal sediment to the surface of the glacier by folding and thrust faulting. We present model and field evidence from the terminus of Storglaciären, Sweden, showing that the cold margin provides limited resistance to flow from up-glacier. Ice temperatures indicate that basal freezing occurs in this zone at 10−1 −10−2 m a−1, but model results indicate that basal motion at rates greater than 1 m a−1 must, nevertheless, persist there for surface and basal velocities to be consistent with measurements. Estimated longitudinal compressive stresses of 20–25 kPa within the terminus further indicate that basal resistance offered by the cold-based terminus is small. These results indicate that where polythermal glaciers are underlain by unlithified sediments, ice-flow trajectories and sediment transport pathways may be affected by subglacial topography and hydrology more than by the basal thermal regime.
Impedance tuners are key instruments used for load- and source–pull measurements. They are crucial for any active microwave components, circuits, and systems characterization and optimization. This paper reports theoretical, simulated, and experimental results related to the development of a novel programmable impedance tuner offering high-voltage standing wave ratio (VSWR). After presenting the proposed tuner principle, a fabricated prototype operating at microwave frequencies and based on a 3.5 mm coaxial line is introduced with experimental results. Depending on the targeted frequency band, different pairs of slugs, with optimized length and characteristic impedance, can be used to obtain an optimal VSWR. This first prototype allowed us to demonstrate the interest of the proposed impedance synthesis principle and to identify ways forward to further improve its performances and push forward this promising technology.
Recent works have demonstrated the feasibility of microwave imaging using compressive techniques, exempting the use of active delay lines, phase shifters, or moving parts to achieve beamforming. With this method, waves are coded in a passive way by a compressive device to reduce the complexity of the transmitter and/or receiver chains of the telecommunication and radar systems requiring beamsteering. Such a technique is based on the exploitation of the frequency diversity, implying that a reduction of the compressive device's volume imposes a diminution of the number of driven antennas. In this paper, the improvement brought by simultaneous excitations of the compressive device is presented. Adapting a new mathematical formulation, it is shown that M inputs can send independent waveforms allowing the beamsteering of an N-elements antenna array, while maintaining N > M.
Whereas broad-scale Amazonian forest types have been shown to influence the structure of the communities of medium- to large-bodied vertebrates, their natural heterogeneity at smaller scale or within the terra firme forests remains poorly described and understood. Diversity indices of such communities and the relative abundance of the 21 most commonly observed species were compared from standardized line-transect data across 25 study sites distributed in undisturbed forests in French Guiana. We first assessed the relevance of a forest typology based on geomorphological landscapes to explain the observed heterogeneity. As previously found for tree beta-diversity patterns, this new typology proved to be a non-negligible factor underlying the beta diversity of the communities of medium- to large bodied vertebrates in French Guianan terra firme forests. Although the species studied are almost ubiquitous across the region, they exhibited habitat preferences through significant variation in abundance and in their association index with the different landscape types. As terra firme forests represent more than 90% of the Amazon basin, characterizing their heterogeneity – including faunal communities – is a major challenge in neotropical forest ecology.
To examine the use of vitamin D supplements during infancy among the participants in an international infant feeding trial.
Information about vitamin D supplementation was collected through a validated FFQ at the age of 2 weeks and monthly between the ages of 1 month and 6 months.
Infants (n 2159) with a biological family member affected by type 1 diabetes and with increased human leucocyte antigen-conferred susceptibility to type 1 diabetes from twelve European countries, the USA, Canada and Australia.
Daily use of vitamin D supplements was common during the first 6 months of life in Northern and Central Europe (>80 % of the infants), with somewhat lower rates observed in Southern Europe (>60 %). In Canada, vitamin D supplementation was more common among exclusively breast-fed than other infants (e.g. 71 % v. 44 % at 6 months of age). Less than 2 % of infants in the USA and Australia received any vitamin D supplementation. Higher gestational age, older maternal age and longer maternal education were study-wide associated with greater use of vitamin D supplements.
Most of the infants received vitamin D supplements during the first 6 months of life in the European countries, whereas in Canada only half and in the USA and Australia very few were given supplementation.
In February 2013, the LEECH (LBTI Exozodi Exoplanet Common Hunt) survey began its 100-night campaign from the Large Binocular Telescope atop Mount Graham in Arizona. LEECH neatly complements other high-contrast planet imaging efforts by observing stars in L' band (3.8 microns) as opposed to the shorter wavelength near-infrared bands (1–2.3 microns). This part of the spectrum offers deeper mass sensitivity for intermediate age (several hundred Myr-old) systems, since their Jovian-mass planets radiate predominantly in the mid-infrared. In this proceedings, we present the science goals for LEECH and a preliminary contrast curve from some early data.
We study foam drainage using the large-Q Potts model extended to include gravity on a three dimensional lattice. Without adding liquid, homogeneously distributed liquid drains to the bottom of the foam until equilibrium between capillary effects and gravity is reached, while in an ordered dry foam, if a fixed amount of liquid is added from the top, a sharp fiat interface between the wet and dry foam develops. The wetting front profile forms a downward moving pulse, with a constant velocity. The pulse decays over time while its leading edge for a brief time behaves like a solitary wave. With continuous liquid addition from the top, the pulse does not decay and we observe a soliton front moving with a constant velocity. Continuously adding liquid to an initially wet foam keeps the liquid profile constant. Our simulations agree with both experimental data and simplified mean field analytical results for ordered foams but predict an unstable interface for disordered foams.
We have simulated the dynamical failure of three-dimensional notched solids under tension using molecular dynamics and up to 100 million atoms. We discovered a dynamical brittle-to-ductile transition in the rapid cleavage of rare-gas solids when the crack velocity approaches one-third of the Rayleigh sound speed. At this transition, the crack tip has already begun to roughen on the atomic scale. This suggests that the brittle crack undergoes a dynamic instability which immediately leads to the initiation of plastic failure by the spontaneous emission and proliferation of dislocations and crack arrest.
A detailed physical analysis of data obtained from static light and dynamic light scattering experiments with polymer-like distearyldimethylammonium OH (DSDMA X) micelles has been undertaken at dilute and semidilute concentrations, and compared with those in the presence of racemic and enantiomeric anions, e.g. S-(+)-lactate or the R-(-)-enantiomer.