1,471 research outputs found
Imipenem resistance in clinical Escherichia coli from Qom, Iran
OBJECTIVE: The emergence of metallo-\u3b2-lactamase-producing Enterobacteriaceae is a worldwide health concern. In this study, the first evaluation of MBL genes, bla IMP and bla VIM , in Escherichia coli resistant to imipenem isolated from urine and blood specimens in Qom, Iran is described. Three hundred urine and blood specimens were analysed to detect the presence of E. coli. Resistance to imipenem and other antimicrobials was determined by disk diffusion and MIC. MBL production was screened using CDDT. PCR was also carried out to determine the presence of bla IMP and bla VIM genes in imipenem-resistant isolates.
RESULTS: In total, 160 E. coli isolates were collected from March to May 2016. According to disk diffusion, high-level of resistance (20%) to cefotaxime was observed, whereas the lowest (1%) was detected for tetracycline. In addition, five isolates showed resistance to imipenem with a MIC\u2009 65\u20094 \ub5g/mL. CDDT test confirmed that five isolates were MBL-producing strains, but no bla IMP and bla VIM genes were detected. Results of this study show a very low level of resistance to imipenem in our geographical area
Photon Self-Induced Spin to Orbital Conversion in TGG crystal at high laser power
In this paper, we present experimental evidence of a newly discovered
third-order nonlinear optical process Self-Induced Spin-to-Orbital Conversion
(SISTOC) of the photon angular momentum. This effect is the physical mechanism
at the origin of the depolarization of very intense laser beams propagating in
isotropic materials. The SISTOC process, like self-focusing, is triggered by
laser heating leading to a radial temperature gradient in the medium. In this
work we tested the occurrence of SISTOC in a terbium gallium garnet (TGG) rod
for an impinging laser power of about 100~W. To study the SISTOC process we
used different techniques: polarization analysis, interferometry and tomography
of the photon orbital angular momentum. Our results confirm, in particular,
that the apparent depolarization of the beam is due to the occurrence of
maximal entanglement between the spin and orbital angular momentum of the
photons undergoing the SISTOC process. This explanation of the true nature of
the depolarization mechanism could be of some help in finding novel methods to
reduce or to compensate for this usually unwanted depolarization effect in all
cases where very high laser power and good beam quality are required.Comment: 6 pages, 10 figures, submitte
Spin-orbit hybrid entanglement of photons and quantum contextuality
We demonstrate electromagnetic quantum states of single photons and of
correlated photon pairs exhibiting "hybrid" entanglement between spin and
orbital angular momentum. These states are obtained from entangled photon pairs
emitted by spontaneous parametric down conversion, by employing a -plate for
coupling the spin and orbital degrees of freedom of a photon. Entanglement and
contextual quantum behavior (that is also non-local, in the case of photon
pairs) is demonstrated by the reported violation of the
Clauser-Horne-Shimony-Holt inequality. In addition a classical analog of the
hybrid spin-orbit photonic entanglement is reported and discussed.Comment: 5 pages, 3 figure
Detection of pathological lesions in slaughtered rabbits
The slaughterhouse is considered an important control point for the monitoring of rabbit diseases. In our study, 59,440 rabbit carcasses were examined, but only 1% of pathological lesions were recorded at postmortem inspection. Mainly affected were tegumentary, digestive and urinary systems. The most consistent lesion was the subcutaneous abscess; nephritis, probably caused by Encephalitozoon cuniculi, was also frequent. Pathological alterations of the liver, classified as "necrotizing hepatitis" and localized at the caudate lobe, were observed for the first time
Detection of Zak phases and topological invariants in a chiral quantum walk of twisted photons
Topological insulators are fascinating states of matter exhibiting protected
edge states and robust quantized features in their bulk. Here, we propose and
validate experimentally a method to detect topological properties in the bulk
of one-dimensional chiral systems. We first introduce the mean chiral
displacement, and we show that it rapidly approaches a multiple of the Zak
phase in the long time limit. Then we measure the Zak phase in a photonic
quantum walk, by direct observation of the mean chiral displacement in its
bulk. Next, we measure the Zak phase in an alternative, inequivalent timeframe,
and combine the two windings to characterize the full phase diagram of this
Floquet system. Finally, we prove the robustness of the measure by introducing
dynamical disorder in the system. This detection method is extremely general,
as it can be applied to all one-dimensional platforms simulating static or
Floquet chiral systems.Comment: 10 pages, 7 color figures (incl. appendices) Close to the published
versio
QUIJOTE Scientific Results. II. Polarisation Measurements of the Microwave Emission in the Galactic molecular complexes W43 and W47 and supernova remnant W44
We present Q-U-I JOint TEnerife (QUIJOTE) intensity and polarisation maps at
10-20 GHz covering a region along the Galactic plane 24<l<45 deg, |b|<8 deg.
These maps result from 210 h of data, have a sensitivity in polarisation of ~40
muK/beam and an angular resolution of ~1 deg. Our intensity data are crucial to
confirm the presence of anomalous microwave emission (AME) towards the two
molecular complexes W43 (22 sigma) and W47 (8 sigma). We also detect at high
significance (6 sigma) AME associated with W44, the first clear detection of
this emission towards a SNR. The new QUIJOTE polarisation data, in combination
with WMAP, are essential to: i) Determine the spectral index of the synchrotron
emission in W44, beta_sync =-0.62 +/-0.03, in good agreement with the value
inferred from the intensity spectrum once a free-free component is included in
the fit. ii) Trace the change in the polarisation angle associated with Faraday
rotation in the direction of W44 with rotation measure -404 +/- 49 rad/m2. And
iii) set upper limits on the polarisation of W43 of Pi_AME <0.39 per cent (95
per cent C.L.) from QUIJOTE 17~GHz, and <0.22 per cent from WMAP 41 GHz data,
which are the most stringent constraints ever obtained on the polarisation
fraction of the AME. For typical physical conditions (grain temperature and
magnetic field strengths), and in the case of perfect alignment between the
grains and the magnetic field, the models of electric or magnetic dipole
emissions predict higher polarisation fractions.Comment: Accepted for publication in MNRA
Carcinoma cells activate AMP-activated protein kinase-dependent autophagy as survival response to kaempferol-mediated energetic impairment.
Kaempferol, a dietary cancer chemopreventive polyphenol, has been reported to trigger apoptosis in several tumor histotypes, but the mechanism underlying this phenomenon is not fully understood. Here, we demonstrate that in HeLa cells, kaempferol induces energetic failure due to inhibition of both glucose uptake and Complex I of the mitochondrial respiratory chain. As adaptive response, cells activate autophagy, the occurrence of which was established cytofluorometrically, upon acridine orange staining, and immunochemically, by following the increase of the autolysosome-associated form of the microtubule-associated protein light chain 3 (LC3-II). Autophagy is an early and reversible process occurring as survival mechanisms against apoptosis. Indeed, chemical inhibition of autophagy, by incubations with monensin, wortmannin, 3-methyladenine, or by silencing Atg5, significantly increases the extent of apoptosis, which takes place via the mitochondrial pathway, and shortens the time in which the apoptotic markers are detectable. We also demonstrate that autophagy depends on the early activation of the AMP-activated protein kinase (AMPK)/mTOR-mediated pathway. The overexpression of dominant negative AMPK results in a decrease of autophagic cells, a decrement of LC3-II levels, and a significant increase of apoptosis. Experiments performed with another carcinoma cell line yielded the same results, suggesting for kaempferol a unique mechanism of action
SARS-CoV-2 and companion animals: sources of information and communication campaign during the COVID-19 pandemic in Italy
This study analyzed data on the sources and the level of Italians’ awareness on the risk of infection by SARS-CoV-2 at the human–animal interface. Data were collected through a survey-type investigation on a representative sample of the Italian population. Forty-five percent of the interviewees were aware that companion animals could be infected by SARS-CoV-2. However, 29.8% were familiar with preventive measures to adopt to avoid viral transmission between infected humans and companion animals, and only 20.7% knew which companion animals could be at risk of infection. Higher awareness regarding the risk of SARS-CoV-2 transmission between animals and humans (51.7%) and the measures to prevent it (33.3%) was detected among companion animals’ owners. Notably, 40.4% of interviewees were not informed at all. Television broadcasts (26.4%) represented the main source of information, while only 3.5% of the interviewees relied on veterinarians, of which 31.9% considered this source of information as the most trustworthy. Overall, 72.4% of Italians recognized that the communication campaign on COVID-19 and companion animals was inadequate. This survey highlights the need for increasing the public awareness of the risk of companion animals being infected with SARS-CoV-2 and the involvement of professionals in the public communication on zoonoses. © 2023 by the authors
High added-value compounds with antibacterial properties from Ginja Cherries by-products
Purpose: To test the antimicrobial properties of the extracts of stems and leaves of Ginja cherry plant. Both stems and leaves are waste in the production of the cherry liquor and they could be valorised by extracting valuable compounds, making the process more environmentally sustainable.
Methods: The ethanol extracts from both stems and leaves were analysed by LC-ESI/MS to determine the phenolic composition. They were tested against Gram positive and Gram negative bacteria (Bacillus subtilis, Staphylococcus aureus MSSA, Staphylococcus aureus MRSA, Pseudomonas sp., Pseudomonas aeruginosa, Flavobacterium sp., Escherichia coli, Salmonella), using the disk diffusion technique and the broth dilution technique. Results: The extracts showed good antibacterial properties towards Gram positive and Gram negative bacteria. The values of the Minimum Inhibitory Concentration (MIC) were lower for Gram positive bacteria (10–15 mg/ml) than for Gram negative ones (10–100 mg/ml). The values of Minimum Bactericidal Concentration (MBC) were between 2 and 4 times higher than the MICs. Conclusions: The waste from Ginja cherry plants can be successfully employed to extract valuable compounds such as polyphenols, with antibacterial properties.info:eu-repo/semantics/publishedVersio
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