386 research outputs found
Multimodal Magnetic Resonance and Near-Infrared-Fluorescent Imaging of Intraperitoneal Ovarian Cancer Using a Dual-Mode-Dual-Gadolinium Liposomal Contrast Agent.
The degree of tumor removal at surgery is a major factor in predicting outcome for ovarian cancer. A single multimodality agent that can be used with magnetic resonance (MR) for staging and pre-surgical planning, and with optical imaging to aid surgical removal of tumors, would present a new paradigm for ovarian cancer. We assessed whether a dual-mode, dual-Gadolinium (DM-Dual-Gd-ICG) contrast agent can be used to visualize ovarian tumors in the peritoneal cavity by multimodal MR and near infra-red imaging (NIR). Intraperitoneal ovarian tumors (Hey-A8 or OVCAR3) in mice enhanced on MR two days after intravenous DM-Dual Gd-ICG injection compared to controls (SNR, CNR, p < 0.05, n = 6). As seen on open abdomen and excised tumors views and confirmed by optical radiant efficiency measurement, Hey-A8 or OVCAR3 tumors from animals injected with DM-Dual Gd-ICG had increased fluorescence (p < 0.05, n = 6). This suggests clinical potential to localize ovarian tumors by MR for staging and surgical planning, and, by NIR at surgery for resection
The using of regenerative supply ventilation elements to ensure the required air exchange in premises buildings of high integrity
In work questions of air supply ensuring of rooms in buildings of the increased tightness are considered. The description of a design, a way of installation and the principle of work of a recuperative affluent ventilating element are provided
The using of regenerative supply ventilation elements to ensure the required air exchange in premises buildings of high integrity
In work questions of air supply ensuring of rooms in buildings of the increased tightness are considered. The description of a design, a way of installation and the principle of work of a recuperative affluent ventilating element are provided
(p)ppGpp and CodY promote Enterococcus faecalis virulence in a murine model of catheter-associated urinary tract infection
ABSTRACT In Firmicutes, the nutrient-sensing regulators (p)ppGpp, the effector molecule of the stringent response, and CodY work in tandem to maintain bacterial fitness during infection. Here, we tested (p)ppGpp and codY mutant strains of Enterococcus faecalis in a catheter-associated urinary tract infection (CAUTI) mouse model and used global transcriptional analysis to investigate the relationship of (p)ppGpp and CodY. The absence of (p)ppGpp or single inactivation of codY led to lower bacterial loads in catheterized bladders and diminished biofilm formation on fibrinogen-coated surfaces under in vitro and in vivo conditions. Single inactivation of the bifunctional (p)ppGpp synthetase/hydrolase rel did not affect virulence, supporting previous evidence that the association of (p)ppGpp with enterococcal virulence is not dependent on the activation of the stringent response. Inactivation of codY in the (p)ppGpp0 strain restored E. faecalis virulence in the CAUTI model as well as the ability to form biofilms in vitro. Transcriptome analysis revealed that inactivation of codY restores, for the most part, the dysregulated metabolism of (p)ppGpp0 cells. While a clear linkage between (p)ppGpp and CodY with expression of virulence factors could not be established, targeted transcriptional analysis indicates that a possible association between (p)ppGpp and c-di-AMP signaling pathways in response to the conditions found in the bladder may play a role in enterococcal CAUTI. Collectively, data from this study identify the (p)ppGpp-CodY network as an important contributor to enterococcal virulence in catheterized mouse bladder and support that basal (p)ppGpp pools and CodY promote virulence through maintenance of a balanced metabolism under adverse conditions. IMPORTANCE Catheter-associated urinary tract infections (CAUTIs) are one of the most frequent types of infection found in the hospital setting that can develop into serious and potentially fatal bloodstream infections. One of the infectious agents that frequently causes complicated CAUTI is the bacterium Enterococcus faecalis, a leading cause of hospital-acquired infections that are often difficult to treat due to the exceptional multidrug resistance of some isolates. Understanding the mechanisms by which E. faecalis causes CAUTI will aid in the discovery of new druggable targets to treat these infections. In this study, we report the importance of two nutrient-sensing bacterial regulators, named (p)ppGpp and CodY, for the ability of E. faecalis to infect the catheterized bladder of mice
Flood Prediction using MLP, CATBOOST and Extra-Tree Classifier
Flooding can be one of the many devastating natural catastrophes, resulting in the annihilation of life and damaging property. Additionally, it can harm farmland and kill growing crops and trees. Nowadays, rivers and lakes are being destroyed, and the natural water reservoirs are converted into development sites and buildings. Due to this, even just a bit of rain can cause a flood. To minimize the number of fatalities, property losses, and other flood-related issues, an early flood forecast is necessary. Therefore, machine learning methods can be used for the prediction of floods.To forecast the frequency of floods brought on by rainfall, a forecasting system is built using rainfall data. The dataset is trained using various techniques like the MLP classifier, the CatBoost classifier, and the Extra-Tree classifier to predict the occurrence of floods. Finally, the three models' performances are compared and the best model for flood prediction is presented. The MLP, Extra-Tree, and CatBoost models achieved accuracy of 94.5%, 97.9%, and 98.34%, respectively, and it is observed that CatBoost performed well with high accuracy to predict the occurrence of floods
Wind mass transfer in S-type symbiotic binaries III. Confirmation of a wind focusing in EG Andromedae from the nebular [OIII]\lambda 5007 line
Context. The structure of the wind from the cool giants in symbiotic binaries
carries important information for understanding the wind mass transfer to their
white dwarf companions and its fuelling. Aims. In this paper, we indicate a
non-spherical distribution of the neutral wind zone around the red giant (RG)
in the symbiotic binary star, EG And. Methods. We achieved this aim by
analysing the periodic orbital variations of fluxes and radial velocities of
individual components of the H and [OIII]5007 lines observed
on our high-cadence medium (R 11 000) and high-resolution (R 38
000) spectra. Results. The asymmetric shaping of the neutral wind zone at the
near-orbital-plane region is indicated by: (i) the asymmetric course of the
H core emission fluxes along the orbit; (ii) the presence of their
secondary maximum around the orbital phase , which is possibly
caused by the refraction effect; and (iii) the properties of the H
broad wing emission originating by Raman scattering on H atoms. The wind is
substantially compressed from polar directions to the orbital plane as
constrained by the location of the [OIII]5007 line emission zones in
the vicinity of the RG at/around its poles. The corresponding mass-loss rate
from the polar regions of Msun/yr is a factor of lower than the average rate of Msun/yr derived from
nebular emission of the ionised wind from the RG. Furthermore, it is two orders
of magnitude lower than that measured in the near-orbital-plane region from
Rayleigh scattering. Conclusions. The startling properties of the nebular
[OIII]5007 line in EG And provides an independent indication of the
wind focusing towards the orbital plane.Comment: 10 pages, 8 figure
Density asymmetry and wind velocities in the orbital plane of the symbiotic binary EG Andromedae
Context. Non-dusty late-type giants without a corona and large-scale
pulsations represent objects that do not fulfil the conditions under which
standard mass-loss mechanisms can be applied efficiently. The driving mechanism
of their winds is still unknown.
Aims. The main goal of this work is to match the radial velocities of
absorbing matter with a depth in the red giant (RG) atmosphere in the S-type
symbiotic star EG And.
Methods. We measured fluxes and radial velocities of ten FeI absorption lines
from spectroscopic observations with a resolution of ~30 000. At selected
orbital phases, we modelled their broadened profiles, including all significant
broadening mechanisms.
Results. The selected FeI absorption lines at 5151 - 6469A, originate at a
radial distance ~1.03 RG radii from its centre. The corresponding radial
velocity is typically ~1 km/s , which represents a few percent of the terminal
velocity of the RG wind. The high scatter of the radial velocities of several
km/s in the narrow layer of the stellar atmosphere points to the complex nature
of the near-surface wind mass flow. The average rotational velocity of 11 km/s
implies that the rotation of the donor star can contribute to observed focusing
the wind towards the orbital plane. The orbital variability of the absorbed
flux indicates the highest column densities of the wind in the area between the
binary components, even though the absorbing neutral material is geometrically
more extended from the opposite side of the giant. This wind density asymmetry
in the orbital plane region can be ascribed to gravitational focusing by the
white dwarf companion.
Conclusions. Our results suggest that both gravitational and rotational
focusing contribute to the observed enhancement of the RG wind towards the
orbital plane, which makes mass transfer by the stellar wind highly efficient.Comment: 12 pages, 10 figure
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