A single-tier immunoassay using the C6 peptide of VlsE (C6) from Borrelia burgdorferi sensu stricto (Bb) has been proposed as a potential alternative to conventional two-tier testing for the ...serologic diagnosis of Lyme disease in the United States and Europe.
To evaluate the performance of C6 peptide based multiplex Phosphorescence Analysis (PHOSPHAN) for the serologic confirmation of Lyme borreliosis (LB) in Russian patients.
Serum samples (n = 351) were collected from 146 patients with erythema migrans (EM); samples from 131 of these patients were taken several times prior to treatment and at different stages of recovery. The control group consisted of 197 healthy blood donors and 31 patients with other diseases, all from the same highly endemic region of Russia. All samples were analyzed by PHOSPHAN for IgM and IgG to Bb C6, recombinant OspC and VlsE proteins, and C6 peptides from B. garinii and B. afzelii.
IgM and IgG to Bb C6 were identified in 43 and 95 out of 131 patients (32.8 and 72.5%, respectively); seroconversion of IgM antibodies was observed in about half of the patients (51.2%), and of IgG antibodies, in almost all of them (88.4%). Additional detection of OspC-IgM and VlsE-IgM or IgG to C6 from B. garinii or B. afzelii did not contribute significantly to the overall sensitivity of the multiplex immunoassay.
The multiplex phosphorescence immunoassay is a promising method for simultaneously revealing the spectrum of antibodies to several Borrelia antigens. Detection of IgM and IgG to Bb C6 in the sera of EM patients provides effective serologic confirmation of LB and, with high probability, indicates an active infection process.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The Jülich Electric Dipole moment Investigation (JEDI) collaboration aims at a direct measurement of the Electric Dipole Moment (EDM) of protons and deuterons using a storage ring. The measurement is ...based on a polarization measurement. In order to reach highest accuracy, one has to know the exact trajectory through the magnets, especially the quadrupoles, to avoid the influence of magnetic fields on the polarization vector. In this paper, the development of a beam-based alignment technique is described that was developed and implemented at the COoler SYnchrotron (COSY) at Forschungszentrum Jülich. Well aligned quadrupoles permit one to absolutely calibrate the Beam Position Monitors (BPMs). The method is based on the fact that a particle beam, which does not pass through the center of a quadrupole, experiences a deflection. The precision reached by the method is approximately 40μm. Some consequences for the design of a new high precision storage ring for EDM mesasurements are discussed.
—
A Phosphorescence Analysis (PHOSPHAN)-based test system was developed for simultaneous detection of thyroid-stimulating hormone (TSH) and free thyroxin (fT
4
), the markers of thyroid function, in ...dried human blood samples. The immunoassay was performed at the bottom of polystyrene 96-well microplate wells covered with analyte-specific microarrays (0.35 mm in diameter). The detection system consisted of polystyrene nanoparticles (46 ± 14 nm in diameter) with incorporated long luminescent Eu(III) chelate complexes (1960 molecules/particle). Fluorescence intensity was measured in time-resolved mode (TRF). Analytical parameter values and possible limitations of this experimental system were investigated. The system allowed the simultaneous detection of high-molecular-weight and low-molecular-weight compounds in clinically relevant concentration ranges, from 2.0 to 50 pmol/L for free T
4
, and 0.8 to 50 µIU for TSH. The sensitivity of the analysis was 1.0 ± 0.2 pmol/L (fT
4
) and 0.3 ± 0.1 µIU/mL (TSH), which corresponded to the detection thresholds of 3 × 10
–18
mol T
4
and 0.9 × 10
–9
IU TSH. The test determined correctly the TSH and T
4
concentrations in standard samples used in quality assessment programs, as well as the thyroid status of the patients included in the investigation (
n
= 48). Results of hormone detection in dried blood spots with our experimental test system correlated well with the results of hormone detection in serum samples using commercial kits (
r
= 0.9730 for TSH and
r
= 0.8585 for fT
4
). The main drawback of the system was associated with high variability of measurement results (up to 20%), which limits the possibility of its application for the quantification of the hormones level in patient blood. We believe that this system can be useful for detecting thyroid disorders both in the existing programs of neonatal screening for congenital hypothyroidism and in mass screening surveys in risk groups of the adult population, for example, in ecologically unfavorable regions.
Neutrinos were assumed to be massless particles until the discovery of the neutrino oscillation process. This phenomenon indicates that the neutrinos have non-zero masses and the mass eigenstates ...(ν1, ν2, ν3) are mixtures of their flavour eigenstates (νe, νμ, ντ). The oscillations between different flavour eigenstates are described by three mixing angles (θ12, θ23, θ13), two differences of the squared neutrino masses of the ν2/ν1 and ν3/ν1 pairs and a charge conjugation parity symmetry violating phase δCP. The Double Chooz experiment, located near the Chooz Electricité de France reactors, measures the oscillation parameter θ13 using reactor neutrinos. Here, the Double Chooz collaboration reports the measurement of the mixing angle θ13 with the new total neutron capture detection technique from the full data set, yielding sin2(2θ13) = 0.105 ± 0.014. This measurement exploits the multidetector configuration, the isoflux baseline and data recorded when the reactors were switched off. In addition to the neutrino mixing angle measurement, Double Chooz provides a precise measurement of the reactor neutrino flux, given by the mean cross-section per fission 〈σf〉 = (5.71 ± 0.06) × 10−43 cm2 per fission, and reports an empirical model of the distortion in the reactor neutrino spectrum.The Double Chooz collaboration reports the neutrino oscillation parameter θ13 from a measurement of the disappearance of reactor anti-electron neutrinos with the total neutron capture technique.
We present a search for signatures of neutrino mixing of electron anti-neutrinos with additional hypothetical sterile neutrino flavors using the Double Chooz experiment. The search is based on data ...from 5 years of operation of Double Chooz, including 2 years in the two-detector configuration. The analysis is based on a profile likelihood, i.e. comparing the data to the model prediction of disappearance in a data-to-data comparison of the two respective detectors. The analysis is optimized for a model of three active and one sterile neutrino. It is sensitive in the typical mass range
5
×
10
-
3
eV
2
≲
Δ
m
41
2
≲
3
×
10
-
1
eV
2
for mixing angles down to
sin
2
2
θ
14
≳
0.02
. No significant disappearance additionally to the conventional disappearance related to
θ
13
is observed and correspondingly exclusion bounds on the sterile mixing parameter
θ
14
as a function of
Δ
m
41
2
are obtained.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Based on the notion that the local dark-matter field of axions or axionlike particles (ALPs) in our Galaxy induces oscillating couplings to the spins of nucleons and nuclei (via the electric dipole ...moment of the latter and/or the paramagnetic axion-wind effect), we establish the feasibility of a new method to search for ALPs in storage rings. Based on previous work that allows us to maintain the in-plane polarization of a stored deuteron beam for a few hundred seconds, we perform a first proof-of-principle experiment at the Cooler Synchrotron (COSY) to scan momenta near 970 MeV/c. This entails a scan of the spin-precession frequency. At resonance between the spin-precession frequency of deuterons and the ALP-induced electric dipole moment (EDM) oscillation frequency, there is an accumulation of the polarization component out of the ring plane. Since the axion frequency is unknown, the momentum of the beam and, consequently, the spin-precession frequency are ramped to search for a vertical polarization change that occurs when the resonance is crossed. At COSY, four beam bunches with different polarization directions are used to make sure that no resonance is missed because of the unknown relative phase between the polarization precession and the axion or ALP field. A frequency window of 1.5 kHz width around the spin-precession frequency of 121 kHz is scanned. We describe the experimental procedure and a test of the methodology with the help of a radio-frequency Wien filter located on the COSY ring. No ALP resonance is observed. As a consequence, an upper limit of the oscillating EDM component of the deuteron as well as its axion coupling constants are provided.
A
bstract
A
θ
13
oscillation analysis based on the observed antineutrino rates at the Double Chooz far and near detectors for different reactor power conditions is presented. This approach provides a ...so far unique simultaneous determination of
θ
13
and the total background rates without relying on any assumptions on the specific background contributions. The analysis comprises 865 days of data collected in both detectors with at least one reactor in operation. The oscillation results are enhanced by the use of 24.06 days (12.74 days) of reactor-off data in the far (near) detector. The analysis considers the
ν
¯
e
interactions up to a visible energy of 8.5 MeV, using the events at higher energies to build a cosmogenic background model considering fast-neutrons interactions and
9
Li decays. The background-model-independent determination of the mixing angle yields sin
2
(2
θ
13
) = 0
.
094 ± 0
.
017, being the best-fit total background rates fully consistent with the cosmogenic background model. A second oscillation analysis is also performed constraining the total background rates to the cosmogenic background estimates. While the central value is not significantly modified due to the consistency between the reactor-off data and the background estimates, the addition of the background model reduces the uncertainty on
θ
13
to 0.015. Along with the oscillation results, the normalization of the anti-neutrino rate is measured with a precision of 0.86%, reducing the 1.43% uncertainty associated to the expectation.
A
bstract
The yields and production rates of the radioisotopes
9
Li and
8
He created by cosmic muon spallation on
12
C, have been measured by the two detectors of the Double Chooz experiment. The ...identical detectors are located at separate sites and depths, which means that they are subject to different muon spectra. The near (far) detector has an overburden of ∼120 m.w.e. (∼300 m.w.e.) corresponding to a mean muon energy of 32.1 ± 2.0 GeV (63.7 ± 5.5 GeV). Comparing the data to a detailed simulation of the
9
Li and
8
He decays, the contribution of the
8
He radioisotope at both detectors is found to be compatible with zero. The observed
9
Li yields in the near and far detectors are 5.51 ± 0.51 and 7.90 ± 0.51, respectively, in units of 10
−8
μ
−1
g
−1
cm
2
. The shallow overburdens of the near and far detectors give a unique insight when combined with measurements by KamLAND and Borexino to give the first multi-experiment, data driven relationship between the
9
Li yield and the mean muon energy according to the power law
Y
=
Y
0
E
μ
/
1
GeV
α
¯
, giving
α
¯
=
0.72
±
0.06
and
Y
0
= (0.43 ± 0.11) × 10
−8
μ
−1
g
−1
cm
2
. This relationship gives future liquid scintillator based experiments the ability to predict their cosmogenic
9
Li background rates.
A study on cosmic muons has been performed for the two identical near and far neutrino detectors of the Double Chooz experiment, placed at ∼120 and ∼300 m.w.e. underground respectively, including the ...corresponding simulations using the MUSIC simulation package. This characterization has allowed us to measure the muon flux reaching both detectors to be (3.64 ± 0.04) × 10{sup −4} cm{sup −2}s{sup −1} for the near detector and (7.00 ± 0.05) × 10{sup −5} cm{sup −2}s{sup −1} for the far one. The seasonal modulation of the signal has also been studied observing a positive correlation with the atmospheric temperature, leading to an effective temperature coefficient of α {sub T} = 0.212 ± 0.024 and 0.355 ± 0.019 for the near and far detectors respectively. These measurements, in good agreement with expectations based on theoretical models, represent one of the first measurements of this coefficient in shallow depth installations.
A numerical method is proposed for determining the diffusion coefficient of a gas in a solid upon its isothermal penetration through a plane-parallel plate and accumulation in a closed receiving ...volume. The method is tested with the use of mathematical modeling as well as on a specific experimental material.
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