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Various transmission routes contribute to spread of carbapenem-resistant Klebsiella pneumoniae (CRKP) in hospitalized patients. Patients with readmissions during which CRKP is again isolated (“CRKP readmission”) potentially contribute to transmission of CRKP.
To evaluate CRKP readmissions in the Consortium on Resistance against Carbapenems in K. pneumoniae (CRaCKLe).
Cohort study from December 24, 2011, through July 1, 2013.
Multicenter consortium of acute care hospitals in the Great Lakes region.
All patients who were discharged alive during the study period were included. Each patient was included only once at the time of the first CRKP-positive culture.
All readmissions within 90 days of discharge from the index hospitalization during which CRKP was again found were analyzed. Risk factors for CRKP readmission were evaluated in multivariable models.
Fifty-six (20%) of 287 patients who were discharged alive had a CRKP readmission. History of malignancy was associated with CRKP readmission (adjusted odds ratio [adjusted OR], 3.00 [95% CI, 1.32–6.65], P<.01). During the index hospitalization, 160 patients (56%) received antibiotic treatment against CRKP; the choice of regimen was associated with CRKP readmission (P=.02). Receipt of tigecycline-based therapy (adjusted OR, 5.13 [95% CI, 1.72–17.44], using aminoglycoside-based therapy as a reference in those treated with anti-CRKP antibiotics) was associated with CRKP readmission.
Hospitalized patients with CRKP—specifically those with a history of malignancy—are at high risk of readmission with recurrent CRKP infection or colonization. Treatment during the index hospitalization with a tigecycline-based regimen increases this risk.
Infect. Control Hosp. Epidemiol. 2016;37(3):281–288
This study aimed to investigate pepsin as a marker of extra-oesophageal reflux disease by examining its presence in tracheal aspirates and correlating it with macroscopic changes on laryngobronchoscopy, along with the results of standard tests for gastro-oesophageal reflux disease and clinical features.
A retrospective review was undertaken of a cohort of 188 paediatric patients who underwent laryngobronchoscopy at a tertiary children's hospital and for whom pepsin assay results of tracheal aspirates were available. An association analysis was performed.
The mean patient age was 3.99 (3.40–4.58) years, with a male preponderance (55 per cent). Positive changes on laryngobronchoscopy were significantly associated with positive tracheal pepsin findings (p < 0.0001) but not with positive standard gastro-oesophageal reflux disease investigations. A positive pepsin assay was significantly associated with a history of recurrent croup (p = 0.0385) and a diagnosis of cystic fibrosis (p = 0.0232).
Macroscopic changes on laryngobronchoscopy were significantly associated with positive tracheal pepsin findings in this paediatric population, suggesting that extra-oesophageal reflux disease may be a contributing aetiology.
The aim of the present research was to evaluate bovine muscles to be subjected to freeze-drying for an instant meal. Physicochemical and senescence parameters were evaluated. The experimental part was divided into two steps. In the first step, the Semitendinosus muscle was chosen to establish methodology and experimental conditions. Physicochemical, microstructure and senescence parameters were analysed. In the second step, economic bovine muscles such as Semimembranous and Spinalis dorsi were subjected to the same methodology and conditions as in the first step in order to compare them by analysing the same parameters. L* and a* values were statistically significant (P<0.05) for Semimembranous and Spinalis dorsi muscles, showing differences among condition effects and in muscles. Humidity and water activity showed among the muscles analysed that cooked and rehydrated samples did not exhibit differences. Microstructure of Semitendinosus and Semimembranous were not separated and fragmented as occurred with Spinalis dorsi after freeze-drying. Results allowed us to select among the muscles studied that Semimembranous was suitable and economic to be used in an instant meal.
Over the past decade, a growing number of deep imaging surveys have started to provide meaningful constraints on the population of extrasolar giant planets at large orbital separation. Primary targets for these surveys have been carefully selected based on their age, distance and spectral type, and often on their membership to young nearby associations where all stars share common kinematics, photometric and spectroscopic properties. The next step is a wider statistical analysis of the frequency and properties of low mass companions as a function of stellar mass and orbital separation. In late 2009, we initiated a coordinated European Large Program using angular differential imaging in the H band (1.66 μm) with NaCo at the VLT. Our aim is to provide a comprehensive and statistically significant study of the occurrence of extrasolar giant planets and brown dwarfs at large (5-500 AU) orbital separation around ~150 young, nearby stars, a large fraction of which have never been observed at very deep contrast. The survey has now been completed and we present the data analysis and detection limits for the observed sample, for which we reach the planetary-mass domain at separations of ≳50 AU on average. We also present the results of the statistical analysis that has been performed over the 75 targets newly observed at high-contrast. We discuss the details of the statistical analysis and the physical constraints that our survey provides for the frequency and formation scenario of planetary mass companions at large separation.
The efficiency of iron-catalysts in hydrocarbon
decomposition, aimed at growth of carbon nanotubes by chemical vapour
deposition (CVD), is systematically investigated. The synthesis reaction is
carried out at different temperatures (873–1123 K), for
various durations (0.5–6.0 h), using diverse precursor
gases (C2H6 or C4H10) and catalyst supports (SiO2
or Al2O3). A large variety of experimental conditions is explored
by varying amount (0.5–2.0 g), metal load (20 wt.%
and 29 wt.%) and annealing temperature (723–973 K)
of the catalysts and by considering different gas flowing setups, namely, by
changing flow rate (100–240 cc/min) and composition
(H2/precursor/He, with He at 0–63%) of the gas mixture,
flow-rates and flow-ratio of reactant gases (H2:
0–120 cc/min; Precursor Gas:
15–120 cc/min; H2/PG: 0–3). Iron
catalysts encapsulation is shown to be the main factor limiting C yields in
the cases considered, and its changes to be responsible for the broad yield
variations (20–910 wt.%) observed. The results of
analyses, carried out by Raman spectroscopy (RS) and complementary
diagnostics techniques, demonstrate the need of accurately tuning the
manifold growth parameters, in order to fully benefit of the advantages
potentially deriving from a proper choice of precursor gas and
Multiwalled carbon nanotubes (MWCNTs) were synthesised by chemical vapour
deposition (CVD) in a C2H6+H2 atmosphere over
20%Fe/SiO2 catalysts. The influence of synthesis temperature,
flow-rate and flow ratio of the reactant gases, the amount of catalyst
employed and the catalyst reduction temperature on the abundance and
crystalline perfection of product was analysed by scanning electron
microscopy, high-resolution transmission electron microscopy and Raman
spectroscopy. The changes in yield and crystalline perfection, as monitored
by Raman G' band relative intensity, were correlated with the variations of
synthesis temperature, the diverse catalyst surface area and H2/C
supply ratio attained by varying growth conditions. In the range examined,
the lowering of catalyst reduction-temperature turns out to be beneficial
for both yield and crystalline perfection of the MWCNTs. All the other
growth parameters produce opposite effects so the best compromise has to be
Solar cell structures with Sb2SxSe3-x and PbS as absorber layers were fabricated by chemical deposition on commercial transparent conductive oxide coated glass. The solid solution here was prepared by heating at 250°C a Sb2S3 thin film in contact with a chemically deposited Se-thin film. It has a graded band gap of 1-1.8 eV. A PbS thin film deposited on this layer basically fulfils the role of a p+ layer; its role as an absorber is yet to be studied. Open circuit voltage of 560 mV and short circuit current density ¡Ö 1mA/cm2under 1-3 kW/m2 tungsten halogen radiation are characteristics of these cells. Optimization of the film thicknesses and heating may offer prospects for these materials toward alternate thin film solar cell technology.
Late-type MS stars
display optical variability on different time scales due to the presence of photospheric
brightness inhomogeneities produced by surface magnetic fields, analogous to cool spots
and bright faculae observed in the Sun. We are developing methods
to model the optical variability of main-sequence late-type stars
to understand the impact of solar-like activity on the detection
of planetary transits and to significantly improve the detection
efficiency. Our techniques will also allow to map
the longitude distribution of active regions
on stars that harbor planets and to look for a possible connection
between stellar activity and the presence of planets around a star.
The huge amount of CCD photometric data collected by robotic telescopes (as for instance the ICE-T
telescope to be installed at Dome-C) requires a fully automated approach to the reduction and analysis procedures.
To this end, we are developing a pipeline, making use of IRAF, DAOPHOTII and tasks build up by us, which will
enable to automatically extract differential magnitude time series. Both aperture and PSF photometry methods are
used to build a proper sample of comparison stars, with the best method between the two being automatically selected.
Finally, the search of rotational periods is performed. To test our package, we present results obtained using
a 4-year dataset of a field in the Orion Nebula Cluster (ONC) containing about 350 stars (150 of which turned out to be periodic variables).
Scoliosis affects 75 to 90% of patients with non-ambulant Duchenne muscular dystrophy (DMD). Spinal surgery is the treatment of choice but the indication varies among centres. Some offer surgery to all non-ambulant patients, irrespective of scoliosis severity. Early surgery has the advantage of targeting DMD when cardiorespiratory function is preserved, but not all patients develop scoliosis. We report our 10-year experience of scoliosis management in 123 patients with DMD who were at least 17 years old at the time of the study. Scoliosis was absent in 10%, and mild, non-progressive (at least 30°) in 13% of patients. Another 13% had moderate scoliosis (31–50°) and were managed conservatively. Surgery was considered in 57% (70/123) of patients with scoliosis greater than 50° and eventually performed in 35%. The remaining patients either refused surgery (9%) or were unfit because of cardiorespiratory compromise (13%). In a further 7%, scoliosis (greater than 50°), first noted after 14 years of age, was progressing slowly and surgery was not performed. At 17 years there was no difference in survival, respiratory impairment, or sitting comfort among patients managed conservatively or with surgery. One-third (44/123) of our patients were managed satisfactorily without receiving spinal surgery. We provide insight into the natural history of scoliosis in DMD that should help families and clinicians with decision-making when surgery is considered.
SPARC and SPARX are two different initiatives toward an Italian
Free Electron Laser (FEL) source
operating in the Self Amplified Spontaneous
Emission (SASE) mode, in which several national
research institutions are involved. SPARC is a high gain FEL project
devoted to provide a source of visible and VUV radiation while
exploiting the SASE mechanism. An advanced Photo-Injector system,
emittance compensating RF-gun plus a 150 MeV Linac, will inject a high
quality e-beam into the undulator to generate high brilliance FEL
radiation in the visible region at the fundamental wavelength,
(∼500 nm). The production of flat top drive laser beams, high peak
current bunches, and emittance compensation scheme will be investigated
together with the generation of higher harmonic radiation in the VUV
region. SPARX is the direct evolution of such a high gain SASE FEL
toward the 13.5 and 1.5 nm operating wavelengths, at 2.5 GeV. To get
the required value for the bunch peak current, Ipeak ≈
2.5 kA, the “hybrid” scheme, RF-compression stage plus
magnetic chicane, is analyzed and compared with the more standard
double stage of magnetic compression. The two options are reviewed
considering the tolerance to the drive laser pulse phase jitter.
Antimony sulfide thin films (300 nm) have been deposited on glass substrates at 1–10°C from chemical bath. When heated these become crystalline and photoconductive with optical band gap (direct) of 1.7 eV. Thin films formed from chemical baths containing SbCl3 and sodium selenosulfate are of mixed phase Sb2O3/Sb2Se3, which when heated in the presence of Se-vapor converts to single phase Sb2Se3 film with optical band gap of 1.1 eV. Such films possess dark conductivity of 10-8 ohm-1cm-1 and show photosensitivity of two orders. Reaction of Sb2S3-CuS in nitrogen at 400°C produces crystalline, photoconductive p-type CuSbS2 with optical band gap (direct) of 1.5 eV. By controlling the deposition and heating condition, (i)Sb2S3-(p)CuSbS2 layer is formed, which is utilized in a photovoltaic structure, (n)CdS:In-(i)Sb2S3-(p)CuSbS2, with a Voc of 345 mV and Jsc 0.18 mA/cm2 under 1 kW m-2 tungsten halogen illumination. In the case of a structure, CdS:Cl-Sb2S3-Cu2-xSe, Voc of 350 mV and Jsc of 0.5 mA/cm2 are observed.
The work of Black and Scholes  and Merton  suggests that analysis of hedged positions in a continuous time random walk model yields powerful insights into the valuation of financial securities. The present paper extends this methodology in a straightforward fashion to foreign exchange transactions. By adopting the device of hedging in a secondary market for forward currency contracts against a long position in spot currency, a simple statement of boundary conditions for the forward position can be detailed. This allows a direct solution of the continuous time valuation problem that yields the interest rate parity theory.
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