365 research outputs found
Qubit thermometry for micromechanical resonators
We address estimation of temperature for a micromechanical oscillator lying
arbitrarily close to its quantum ground state. Motivated by recent experiments,
we assume that the oscillator is coupled to a probe qubit via Jaynes-Cummings
interaction and that the estimation of its effective temperature is achieved
via quantum limited measurements on the qubit. We first consider the ideal
unitary evolution in a noiseless environment and then take into account the
noise due to non dissipative decoherence. We exploit local quantum estimation
theory to assess and optimize the precision of estimation procedures based on
the measurement of qubit population, and to compare their performances with the
ultimate limit posed by quantum mechanics. In particular, we evaluate the
Fisher information (FI) for population measurement, maximize its value over the
possible qubit preparations and interaction times, and compare its behavior
with that of the quantum Fisher information (QFI). We found that the FI for
population measurement is equal to the QFI, i.e., population measurement is
optimal, for a suitable initial preparation of the qubit and a predictable
interaction time. The same configuration also corresponds to the maximum of the
QFI itself. Our results indicate that the achievement of the ultimate bound to
precision allowed by quantum mechanics is in the capabilities of the current
technology.Comment: 9 pages, 5 figures, revised version, to appear on PR
Personalizzazione della terapia farmacologica di disassuefazione tabagica: valutazioni farmacogenetiche e farmacocinetiche
CAPITOLO 1
GENERALITA’ SULLA NICOTINA
La nicotina è il più importante alcaloide contenuto nelle foglie della pianta Nicotiana tabacum. Il nome di Nicotiana alla pianta e, quindi, di nicotina al suo alcaloide, deriva da Jean Nicot de Villemain, ambasciatore francese in Portogallo, che introdusse i semi in Francia e ne promosse la coltivazione e l’uso medico1. La nicotina si trova nelle foglie in una percentuale che va da 0,17% a 5% e la variabilità è data dai diversi cultivars, i processi di raccolta, immagazzinamento e lavorazione2
Action and non-action oriented body representations. insight from behavioural and grey matter modifications in individuals with lower limb amputation
Following current model of body representations, we aimed to systematically investigate the association between brain modifications, in terms of grey matter loss, and body representation deficits, in terms of alterations of the body schema (BS) and of non-action oriented body representations (NA), in individuals with lower limb amputation (LLA)
Twin-to-twin transfusion syndrome: diagnostic imaging and its role in staving off malpractice charges and litigation
The study aims to expound upon the imaging-based diagnostic methodologies aimed at identifying twin-to-twin transfusion syndrome (TTTS), a serious, somewhat rare prenatal condition that takes place in pregnancies where identical twins, or other multiples, share a placenta (monochorionic placenta), highlighting how medico-legal outcomes can be affected by provable compliance with consolidated diagnostic guidelines or best practices. It is of utmost importance to produce a prompt identification of TTTS instances; an early diagnosis is in fact critical in order to effectively treat and manage TTTS. By virtue of TTTS being a highly progressive condition, a delay in diagnosis can result in disastrous outcomes; just a few weeks delay in the diagnosis of TTTS can turn out fatal for one or both twins. Hence, most TTTS malpractice claims involve allegations of medical negligence, namely the failure to recognize the condition in a timely fashion, or to proceed with adequate diagnostic and therapeutic pathways. In that regard, case law databases have been pored over (Justia, Lexis, Leagle), and five significant court cases have been examined and discussed in an attempt to identify objective medico-legal standards and bring to the forefront relevant forensic dynamics. In fact, when health professionals are capable of proving adherence to guidelines or best practices, this can shield them from malpractice allegations and ensuing litigation
Susceptibility of the C2 canine mastocytoma cell line to the effects of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)
In the context of bipartite bosonic systems, two notions of classicality of
correlations can be defined: P-classicality, based on the properties of the
Glauber-Sudarshan P-function; and C-classicality, based on the entropic quantum
discord. It has been shown that these two notions are maximally inequivalent in
a static (metric) sense -- as they coincide only on a set of states of zero
measure. We extend and reinforce quantitatively this inequivalence by
addressing the dynamical relation between these types of non-classicality in a
paradigmatic quantum-optical setting: the linear mixing at a beam splitter of a
single-mode Gaussian state with a thermal reference state. Specifically, we
show that almost all P-classical input states generate outputs that are not
C-classical. Indeed, for the case of zero thermal reference photons, the more
P-classical resources at the input the less C-classicality at the output. In
addition, we show that the P-classicality at the input -- as quantified by the
non-classical depth -- does instead determine quantitatively the potential of
generating output entanglement. This endows the non-classical depth with a new
operational interpretation: it gives the maximum number of thermal reference
photons that can be mixed at a beam splitter without destroying the output
entanglement.Comment: 13 pages, 10 figure
The conventional non-articulated SACH or a multiaxial prosthetic foot for hypomobile transtibial amputees? A clinical comparison on mobility, balance, and quality of life
The effects of a non-articulated SACH and a multiaxial foot-ankle mechanism on the performance of low-activity users are of great interest for practitioners in amputee rehabilitation.The aim of this study is to compare these two prosthetic feet and assess possible improvements introduced by the increased degrees of freedom provided by the multiaxial foot. For this purpose, a group of 20 hypomobile transtibial amputees (TTAs) had their usual SACH replaced with a multiaxial foot. Participants’ functional mobility, involving ambulatory skills in overground level walking, ramps, and stairs, was evaluated by performing Six-Minute Walking Test (6MWT), Locomotor Capability Index-5 (LCI-5), Hill Assessment Index (HAI), and Stair Assessment Index (SAI). Balance performances were assessed using Berg Balance Scale (BBS) and analysing upper body accelerations during gait.Moreover, the Prosthesis Evaluation Questionnaire (PEQ) was performed to indicate the prosthesis-related quality of life. Results showed that participants walked faster using themultiaxial foot ( < 0.05) maintaining the same upright gait stability. Significant improvements with themultiaxial foot were also observed in BBS, LCI-5, and SAI times and 4 of 9 subscales of the PEQ. Our findings demonstrate that a multiaxial foot represents a considerable alternative solution with respect to the conventional SACH in the prosthetic prescription for hypomobile TTAs
Diagnostic study on an immunochromatographic rapid test for schistosomiasis: comparison between use on serum and on blood spot from fingerprick
An immunochromatographic rapid test (ICT; Schistosoma ICT IgG-IgM, LDBIO Diagnostics) demonstrated high sensitivity (96%) in the diagnosis ofSchistosoma mansoniandS. haematobium. To date, the test has been validated for use on serum only, but in the absence of lab equipment, blood drop from fingerprick could be a useful option. This method is acquiring more interest because of the high flow of migrants rapidly moving across Italy and other European countries
Qubit-assisted thermometry of a quantum harmonic oscillator
We use the theory of quantum estimation in two different qubit-boson coupling
models to demonstrate that the temperature of a quantum harmonic oscillator can
be estimated with high precision by quantum-limited measurements on the qubit.
The two models that we address embody situations of current physical interest
due to their connection with ongoing experimental efforts on the control of
mesoscopic dynamics. We show that population measurements performed over the
qubit probe are near optimal for a broad range of temperatures of the harmonic
oscillatorComment: 7 pages, 5 figure
RASSF1 tumor suppressor gene in pancreatic ductal adenocarcinoma: correlation of expression, chromosomal status and epigenetic changes
Background: The Ras Association Domain Family Member 1 (RASSF1) is one of the most frequently reported methylation-inactivated tumor suppressor genes in primary pancreatic ductal adenocarcinomas (PDAC). Limited information is still available about the impact of RASSF1 gene silencing on the expression of its different isoforms in neoplastic cells. Methods: A series of 96 primary PDAC, with known clinico-pathological parameters, was tested for RASSF1 methylation status by methylation-specific PCR, RASSF1 locus copy number alterations by fluorescence in situ hybridization, and Rassf1a protein expression by immunohistochemistry. A further series of 14 xenografted primary PDAC and 8 PDAC-derived cell lines were tested to obtain a detailed methylation mapping of CpG islands A and C of the RASSF1 locus by pyrosequencing and to evaluate the expression of Rassf1 variants by qRT-PCR. Results: Methylation of CpG island A of the RASSF1 gene was observed in 35% of the tumors and allelic loss of RASSF1 locus was seen in 30 disomic and in 20 polysomic cases (52%). Rassf1a immunohistochemical expression was downregulated in half of primary PDAC, and this downregulation was neither correlated with methylation of RASSF1 promoter nor with RASSF1 copy number alterations. RASSF1 status did not influence patients' prognosis. The expression of the seven RASSF1 isoforms in xenografts and cell lines showed that RASSF1A, RASSF1B, and RASSF1C isoforms were present in all xenografts and cell lines, whereas RASSF1D, RASSF1E, and RASSF1F isoforms were variably expressed among samples. RASSF1G was never expressed in either xenografts or cell lines. The variable expression of RASSF1 isoforms in PDAC xenografts and cell lines was not dependent on RASSF1 methylation status of CpG islands A and C. Conclusions:RASSF1 alterations occurring in PDAC mainly consist in variations of expression of the different isoforms. Different genetic mechanisms seem to contribute to RASSF1 deregulation in this setting, but RASSF1 methylation does not seem to substantially affect RASSF1 isoforms expression
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