1,738 research outputs found
On-line reverse isotope dilution analysis for spatial quantification of elemental labels used in immunohistochemical assisted imaging mass spectrometry: Via LA-ICP-MS
© 2019 The Royal Society of Chemistry. We present a novel on-line isotope dilution analysis (IDA) approach for the quantification of isotopically enriched metal labels used in immunohistochemical assisted imaging mass spectrometry. This technique advances recently reported on-line IDA for laser ablation-inductively coupled plasma mass spectrometry (LA-ICP-MS) by performing on-line reverse IDA of isotopically enriched elements commonly used as labels for antibodies. This approach allows relative quantification of biomolecules and is superior to other methods that have long acquisition times such as three-dimensional LA-ICP-MS, or when higher sample throughput is required. As a proof of concept, anti-tyrosine hydroxylase was labelled with Yb isotopes and incubated on two parallel cryocut sections of a mouse brain. IDA dependent parameters were determined by ablation of matrix-matched standards. Quantification by IDA was compared against external calibration and was a more robust method, unaffected by sensitivity changes originating from plasma drifts or spontaneous plasma fluctuations
Boundary K-matrices for the XYZ, XXZ AND XXX spin chains
The general solutions for the factorization equations of the reflection
matrices for the eight vertex and six vertex models (XYZ, XXZ
and XXX chains) are found. The associated integrable magnetic Hamiltonians are
explicitly derived, finding families dependig on several continuous as well as
discrete parameters.Comment: 13 page
New Phenomenon of Nonlinear Regge Trajectory and Quantum Dual String Theory
The relation between the spin and the mass of an infinite number of particles
in a -deformed dual string theory is studied. For the deformation parameter
a root of unity, in addition to the relation of such values of with the
rational conformal field theory, the Fock space of each oscillator mode in the
Fubini-Veneziano operator formulation becomes truncated. Thus, based on general
physical grounds, the resulting spin-(mass) relation is expected to be
below the usual linear trajectory. For such specific values of , we find
that the linear Regge trajectory turns into a square-root trajectory as the
mass increases.Comment: 12 pages, Latex, HU-SEFT R 1994-0
Near infrared and optical morphology of the dusty galaxy NGC972
Near infrared (NIR) and optical surface photometric analyses of the dusty
galaxy NGC972 are presented. The photometric profiles in the BVRJHK bands can
be fitted with a combination of gaussian and exponential profiles,
corresponding to a starburst nucleus and a stellar disk respectively. The
exponential scale length in the B-band is 2.8 times larger than in the K-band,
which implies a central B-band optical depth as high as 11. A bulge is absent
even in the NIR bands and hence the galaxy must be of a morphological type
later than the usually adopted Sb type. Relatively low rotational velocity and
high gas content also favor a later type, probably Sd, for the galaxy. Only one
arm can be traced in the distribution of old stars; the second arm, however,
can be traced in the distribution of dust and HII regions. Data suggest a short
NIR bar, which ends inside the nuclear ring. The slowly rising nature of the
rotation curve rules out a resonance origin of the the nuclear ring. The ring
is most likely not in the plane of the galaxy, given its circular appearance in
spite of the moderately high inclination of the galaxy. The off-planar nature
of the star forming ring, the unusually high fraction (30%) of the total mass
in molecular form, the presence of a nuclear starburst and the asymmetry of
spiral arms, are probably the result of a merger with a gas-rich companion
galaxy.Comment: Uses aas2pp4.sty and epsfig.sty, 12 pages To appear in Astronomical
Journal, October 199
Matching sensitivity to abundance: High resolution immuno-mass spectrometry imaging of lanthanide labels and endogenous elements in the murine brain
© 2020 The Royal Society of Chemistry. This work introduces a new method for immuno-mass spectrometry imaging via quadrupole-based laser ablation-inductively coupled plasma-mass spectrometry instruments that is matched to the abundance of elements in biological tissues. Manipulation of ion-optics and quadrupole mass filter parameters provided increased transmission of low level high-mass elements, which are typically used as labels for antibodies, at the expense of highly abundant endogenous low-mass elements. Transmission of mid-mass elements such as transition metals was only slightly affected. The implications for mass resolution and background signals are critically discussed and signal to noise ratios and imaging capabilities are compared to those obtained from a standard method. This novel approach resulted in a 6-fold improved signal to noise ratio for lanthanides that are routinely used as elemental labels for antibodies to target protein distributions in biological tissues. This increase in signal intensity, enhanced contrasts, lower limits of detection and the potential to improve spatial resolution contributed to enhanced imaging and trace analyses, as demonstrated by imaging murine brain sections of the hippocampal system and substantia nigra
Exact diagonalization of the generalized supersymmetric t-J model with boundaries
We study the generalized supersymmetric model with boundaries in three
different gradings: FFB, BFF and FBF. Starting from the trigonometric R-matrix,
and in the framework of the graded quantum inverse scattering method (QISM), we
solve the eigenvalue problems for the supersymmetric model. A detailed
calculations are presented to obtain the eigenvalues and Bethe ansatz equations
of the supersymmetric model with boundaries in three different
backgrounds.Comment: Latex file, 32 page
Phase diagram of the anti-ferromagnetic xxz model in the presence of an external magnetic field
The anisotropic s=1/2 anti-ferromagnetic Heisenberg chain in the presence of
an external magnetic field is studied by using the standard quantum
renormalization group. We obtain the critical line of the transition from
partially magnetized (PM) phase to the saturated ferromagnetic (SFM) phase. The
crossover exponent between the PM phase and anti-ferromagnetic Ising (AFI)
phase is evaluated. Our results show that the anisotropy(\d) term is relevant
and causes crossover. These results indicate that the standard RG approach
yields fairly good values for the critical points and their exponents. The
magnetization curve, correlation functions and the ground state energy per site
are obtained and compared with the known exact results.Comment: A LaTex file(20 pages) and 9 PS figure
Efficacy and safety of the combination of reduced duration prophylaxis followed by immuno-guided prophylaxis to prevent cytomegalovirus disease in lung transplant recipients (CYTOCOR STUDY) : An open-label, randomised, non-inferiority clinical trial
Introduction Prolonged use of antivirals to prevent the development of cytomegalovirus (CMV) disease in lung transplant patients has been shown to have significant side effects, for which alternatives are being sought to reduce their use. The monitoring of cell immunity against CMV could be an alternative as it has shown to be useful in identifying transplant patients at low risk of infection, who could benefit from shorter prophylaxis. The aim of the CYTOCOR study is to demonstrate that the combination of a reduced prophylaxis strategy with subsequent CMV-specific immunological monitoring would allow CMV infection to be controlled in lung transplant patients as effectively as the usual strategy (prophylaxis followed by pre-emptive therapy), while reducing the side effects of antivirals due to the shorter duration of prophylaxis. Methods and analysis Phase III randomised, open, multicentre, parallel, non-inferiority clinical trial to study the efficacy and safety of the combination of a prophylaxis strategy up to month +3 post-transplant followed by immuno-guided prophylaxis using the QuantiFERON-CMV technique up to month +12 post-transplant to prevent CMV disease in CMV-seropositive lung transplant recipients. This strategy will be compared with a combination of a usual prophylaxis strategy up to month +6 post-transplant followed by pre-emptive therapy up to month +12. To study the incidence of CMV disease, patients will be followed up to 18 months post-transplantation. A total of 150 patients are expected to be recruited for the study. Ethics and public dissemination The clinical trial has been approved by the Research Ethics Committees and authorised by the Spanish Agency of Medicines and Medical Devices (AEMPS). If the hypothesis of this clinical trial is verified, the dissemination of the results could change clinical practice by increasing knowledge about the safety and efficacy of discontinuing valganciclovir prophylaxis in lung transplant recipients. Trial registration number NCT03699254
Anyon in External Electromagnetic Field: Hamiltonian and Lagrangian Formulations
We propose a simple model for a free relativistic particle of fractional spin
in 2+1 dimensions which satisfies all the necessary conditions. The canonical
quantization of the system leads to the description of one- particle states of
the Poincare group with arbitrary spin. Using the Hamil- tonian formulation
with the set of constraints, we introduce the electro- magnetic interaction of
a charged anyon and obtain the Lagrangian. The Casimir operator of the extended
algebra, which is the first-class constraint, is obtained and gives the
equation of motion of the anyon. In particular, from the latter it follows that
the gyromagnetic ratio for a charged anyon is two due to the parallelness of
spin and momentum of the particle in 2+1 dimensions. The canonical quantization
is also considered in this case.Comment: 9 pages, Latex, HU-SEFT R 1993-1
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