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A case–case-control investigation (N = 255 patients) explored the epidemiology of carbapenem-resistant Pseudomonas aeruginosa (CRPA). Recent exposure to carbapenems and a rapidly fatal condition should prompt practitioners to shorten delays in initiating appropriate therapy, which can adversely impact CRPA outcomes, as opposed to the isolated impact of the carbapenem resistance determinant.
Certain geological features have been interpreted as evidence of channelized magma flow in the mantle, which is a compacting porous medium. Aharonov et al. (J. Geophys. Res., vol. 100 (B10), 1995, pp. 20433–20450) developed a simple model of reactive porous flow and numerically analysed its instability to channels. The instability relies on magma advection against a chemical solubility gradient and the porosity-dependent permeability of the porous host rock. We extend the previous analysis by systematically mapping out the parameter space. Crucially, we augment numerical solutions with asymptotic analysis to better understand the physical controls on the instability. We derive scalings for the critical conditions of the instability and analyse the associated bifurcation structure. We also determine scalings for the wavelengths and growth rates of the channel structures that emerge. We obtain quantitative theories for and a physical understanding of, first, how advection or diffusion over the reactive time scale sets the horizontal length scale of channels and, second, the role of viscous compaction of the host rock, which also affects the vertical extent of channelized flow. These scalings allow us to derive estimates of the dimensions of emergent channels that are consistent with the geologic record.
This work is part of the interlaboratory collaboration to study the stability of organic solar cells containing PCDTBT polymer as a donor material. The varieties of the OPV devices with different device architectures, electrode materials, encapsulation, and device dimensions were prepared by seven research laboratories. Sets of identical devices were aged according to four different protocols: shelf lifetime, laboratory weathering under simulated illumination at ambient temperature, laboratory weathering under simulated illumination, and elevated temperature (65 °C) and daylight outdoor weathering under sunlight. The results generated in this study allow us to outline several general conclusions related to PCDTBT-based bulk heterojunction (BHJ) solar cells. The results herein reported can be considered as practical guidance for the realization of stabilization approaches in BHJ solar cells containing PCDTBT.
To measure transmission frequencies and risk factors for household acquisition of community-associated and healthcare-associated (HA-) methicillin-resistant Staphylococcus aureus (MRSA).
DESIGN
Prospective cohort study from October 4, 2008, through December 3, 2012.
SETTING
Seven acute care hospitals in or near Toronto, Canada.
PARTICIPANTS
Total of 99 MRSA-colonized or MRSA-infected case patients and 183 household contacts.
METHODS
Baseline interviews were conducted, and surveillance cultures were collected monthly for 3 months from household members, pets, and 8 prespecified high-use environmental locations. Isolates underwent pulsed-field gel electrophoresis and staphylococcal cassette chromosome mec typing.
RESULTS
Overall, of 183 household contacts 89 (49%) were MRSA colonized, with 56 (31%) detected at baseline. MRSA transmission from index case to contacts negative at baseline occurred in 27 (40%) of 68 followed-up households. Strains were identical within households. The transmission risk for HA-MRSA was 39% compared with 40% (P=.95) for community-associated MRSA. HA-MRSA index cases were more likely to be older and not practice infection control measures (P=.002–.03). Household acquisition risk factors included requiring assistance and sharing bath towels (P=.001–.03). Environmental contamination was identified in 78 (79%) of 99 households and was more common in HA-MRSA households.
CONCLUSION
Household transmission of community-associated and HA-MRSA strains was common and the difference in transmission risk was not statistically significant.
No One would accuse Martin Luther of being philo-Semitic. Even his first, so-called pro-Jewish pamphlet to the Jews is tentative in the extreme and conditional on their accepting Christianity in its purer Protestant form. But even he could not disguise his admiration for the Jews in two areas. The first was sheer survival.
The Jews are the poorest people among all nations on earth [he said], they are plagued every where, scattered to and fro in all Countries, they have no certain place, they sit like as on a wheel-barrow, have no Countrie, people nor Government, yet they attend with great desire, they cheer up themselves and saie, It will bee soon better with us.
The goal of the present study was to apply experimental economic methods in an online supermarket to examine the effects of nutrient profiling, and differential pricing based on the nutrient profile, on the overall diet quality, energy and macronutrients of the foods purchased, and diet cost.
Design
Participants were provided nutrient profiling scores or price adjustments based on nutrient profile scores while completing a hypothetical grocery shopping task. Prices of foods in the top 20 % of nutrient profiling scores were reduced (subsidized) by 25 % while those in the bottom 20 % of scores were increased (taxed) by 25 %. We evaluated the independent and interactive effects of nutrient profiling or price adjustments on overall diet quality of foods purchased as assessed by the NuVal® score, energy and macronutrients purchased and diet cost in a 2×2 factorial design.
Setting
A large (>10 000 food items) online experimental supermarket in the USA.
Subjects
Seven hundred and eighty-one women.
Results
Providing nutrient profiling scores improved overall diet quality of foods purchased. Price changes were associated with an increase in protein purchased, an increase in energy cost, and reduced carbohydrate and protein costs. Price changes and nutrient profiling combined were associated with no unique benefits beyond price changes or nutrient profiling alone.
Conclusions
Providing nutrient profile score increased overall NuVal® score without a reduction in energy purchased. Combining nutrient profiling and price changes did not show an overall benefit to diet quality and may be less useful than nutrient profiling alone to consumers who want to increase overall diet quality of foods purchased.
The high-speed impact of a droplet on a bulk fluid at high Weber number (We) is not well understood but is relevant to the production of marine aerosol by raindrop impact on the sea surface. These splashes produce a subsurface cavity and a crown which closes into a bubble canopy, but a floating layer of immiscible oil, such as a crude oil slick, alters the splash dynamics. The effects of oil layer fluid properties and thickness, droplet size and impact speed are examined by high-speed visualization. Oil layer rupture and crown behaviour are classified by dimensional scaling. The subsurface cavity volume for impact on thick layers is shown to depend on the Reynolds number (Re), although canopy formation at high Re introduces a competing We effect since rapid canopy closure is found to retard cavity expansion. Time-resolved kinematic measurements show that thin crude oil slicks similarly alter crown closure and cavity growth. The size and spatial distributions of airborne droplets are examined using high-speed holographic microscopy. The droplets have a bimodal distribution with peaks at 50 and
$225~{\rm\mu}\text{m}$
and are clustered by size at different elevation angles. Small droplets (
$50~{\rm\mu}\text{m}$
) are ejected primarily at shallow angles, indicating production by splashing within the first
$100~{\rm\mu}\text{s}$
and by breakup of microligaments. Larger droplets (
$225~{\rm\mu}\text{m}$
) are found at steeper elevation angles, indicating later production by capillary instability acting on large ligaments protruding upward from the crown. Intermittent droplet release while the ligaments grow and sweep upward is thought to contribute to the size-dependent spatial ordering. Greater numbers of small droplets are produced at high elevation angles when a crude oil layer is present, indicating satellite droplet formation from ligament breakup. A crude oil layer also increases the target fluid Ohnesorge number, leading to creation of an intact ejecta sheet, which then ruptures to form aerosolized oil droplets.
Gaia's Radial Velocity Spectrometer (RVS) has been operating in routine phase for over one year since initial commissioning. RVS continues to work well but the higher than expected levels of straylight reduce the limiting magnitude. The end-of-mission radial-velocity (RV) performance requirement for G2V stars was 15 km s−1 at V = 16.5 mag. Instead, 15 km s−1 precision is achieved at 15 < V < 16 mag, consistent with simulations that predict a loss of 1.4 mag. Simulations also suggest that changes to Gaia's onboard software could recover ~0.14 mag of this loss. Consequently Gaia's onboard software was upgraded in April 2015. The status of this new commissioning period is presented, as well as the latest scientific performance of the on-ground processing of RVS spectra. We illustrate the implications of the RVS limiting magnitude on Gaia's view of the Milky Way's halo in 6D using the Gaia Universe Model Snapshot (GUMS).
Let
$X$
be a curve over a number field
$K$
with genus
$g\geq 2$
,
$\mathfrak{p}$
a prime of
${ \mathcal{O} }_{K} $
over an unramified rational prime
$p\gt 2r$
,
$J$
the Jacobian of
$X$
,
$r= \mathrm{rank} \hspace{0.167em} J(K)$
, and
$\mathscr{X}$
a regular proper model of
$X$
at
$\mathfrak{p}$
. Suppose
$r\lt g$
. We prove that
$\# X(K)\leq \# \mathscr{X}({ \mathbb{F} }_{\mathfrak{p}} )+ 2r$
, extending the refined version of the Chabauty–Coleman bound to the case of bad reduction. The new technical insight is to isolate variants of the classical rank of a divisor on a curve which are better suited for singular curves and which satisfy Clifford’s theorem.
We study the topology of tropical varieties that arise from a certain natural class of varieties. We use the theory of tropical degenerations to construct a natural, “multiplicity-free” parameterization of Trop
$\left( X \right)$
by a topological space
${{\Gamma }_{X}}$
and give a geometric interpretation of the cohomology of
${{\Gamma }_{X}}$
in terms of the action of a monodromy operator on the cohomology of
$X$
. This gives bounds on the Betti numbers of
${{\Gamma }_{X}}$
in terms of the Betti numbers of
$X$
which constrain the topology of Trop
$\left( X \right)$
. We also obtain a description of the top power of the monodromy operator acting on middle cohomology of
$X$
in terms of the volume pairing on
${{\Gamma }_{X}}$
.
In prior research, specimen holders that employ a novel MEMS-based heating technology (AduroTM) provided by Protochips Inc. (Raleigh, NC, USA) have been shown to permit sub-Ångström imaging at elevated temperatures up to 1,000°C during in situ heating experiments in modern aberration-corrected electron microscopes. The Aduro heating devices permit precise control of temperature and have the unique feature of providing both heating and cooling rates of 106°C/s. In the present work, we describe the recent development of a new specimen holder that incorporates the Aduro heating device into a “closed-cell” configuration, designed to function within the narrow (2 mm) objective lens pole piece gap of an aberration-corrected JEOL 2200FS STEM/TEM, and capable of exposing specimens to gases at pressures up to 1 atm. We show the early results of tests of this specimen holder demonstrating imaging at elevated temperatures and at pressures up to a full atmosphere, while retaining the atomic resolution performance of the microscope in high-angle annular dark-field and bright-field imaging modes.