1,403 research outputs found
Poly(2-oxazolines) in biological and biomedical application contexts.
Polyoxazolines of various architectures and chemical functionalities can be prepared in a living and therefore controlled manner via cationic ring-opening polymerisation. They have found widespread applications, ranging from coatings to pigment dispersants. Furthermore, several polyoxazolines are water-soluble or amphiphilic and relatively non-toxic, which makes them interesting as biomaterials. This paper reviews the development of polyoxazoline-based polymers in biological and biomedical application contexts since the beginning of the millennium. This includes nanoscalar systems such as membranes and nanoparticles, drug and gene delivery applications, as well as stimuli-responsive systems
Emission spectra from single rovibronic quantum states in S1 benzene after Doppler-free two-photon excitation
Dispersed emission from single rovibronic quantum states in S1 benzene is measured after Doppler-free two-photon excitation under low pressure conditions (0.3 Torr). This was made possible by a long-term stabilization of the single-mode dye laser yielding a stability of better than 1 MHz/h. The emission spectra of unperturbed rotational levels in the 141 and the 14111 vibronic states reveal a great number of detailed results on Duschinsky rotation and long-range Fermi resonances in the electronic ground state. By contrast, it is seen that the emission spectra from perturbed rovibronic states are contaminated by additional bands. The analysis of these bands leads in most cases to an identification of the coupled dark background state and the responsible rotation–vibration coupling process (H42 resonances). The emission spectra clearly demonstrate that even for a density of states of 60 1/cm−1, coupling in S1 benzene is still selective and far from the statistical limit. It is further demonstrated that the dark and the light states are more efficiently mixed by short-range couplings with coupling matrix elements of some GHz than by long-range Fermi resonances. The Journal of Chemical Physics is copyrighted by The American Institute of Physics
Master integrals for the NNLO virtual corrections to scattering in QED: the planar graphs
We evaluate the master integrals for the two-loop, planar box-diagrams
contributing to the elastic scattering of muons and electrons at
next-to-next-to leading-order in QED. We adopt the method of differential
equations and the Magnus exponential series to determine a canonical set of
integrals, finally expressed as a Taylor series around four space-time
dimensions, with coefficients written as combination of generalised
polylogarithms. The electron is treated as massless, while we retain full
dependence on the muon mass. The considered integrals are also relevant for
crossing-related processes, such as di-muon production at -colliders,
as well as for the QCD corrections to -pair production at hadron
colliders.Comment: published version, 39 pages, 7 figures, 3 ancillary file
Three-loop master integrals for ladder-box diagrams with one massive leg
The three-loop master integrals for ladder-box diagrams with one massive leg
are computed from an eighty-five by eighty-five system of differential
equations, solved by means of Magnus exponential. The results of the considered
box-type integrals, as well as of the tower of vertex- and bubble-type master
integrals associated to subtopologies, are given as a Taylor series expansion
in the dimensional regulator parameter epsilon = (4-d)/2. The coefficients of
the series are expressed in terms of uniform weight combinations of multiple
polylogarithms and transcendental constants up to weight six. The considered
integrals enter the next-to-next-to-next-to-leading order virtual corrections
to scattering processes like the three-jet production mediated by vector boson
decay, V* -> jjj, as well as the Higgs plus one-jet production in gluon fusion,
pp -> Hj.Comment: 44 pages, 5 figures, 2 ancillary file
Two-loop master integrals for the leading QCD corrections to the Higgs coupling to a pair and to the triple gauge couplings and
We compute the two-loop master integrals required for the leading QCD
corrections to the interaction vertex of a massive neutral boson , e.g.
or , with a pair of bosons, mediated by a quark
doublet composed of one massive and one massless flavor. All the external legs
are allowed to have arbitrary invariant masses. The Magnus exponential is
employed to identify a set of master integrals that, around space-time
dimensions, obey a canonical system of differential equations. The canonical
master integrals are given as a Taylor series in , up to
order four, with coefficients written as combination of Goncharov
polylogarithms, respectively up to weight four. In the context of the Standard
Model, our results are relevant for the mixed EW-QCD corrections to the Higgs
decay to a pair, as well as to the production channels obtained by
crossing, and to the triple gauge boson vertices and .Comment: 42 pages, 5 figures, 2 ancillary file
Two-Loop Master Integrals for the mixed EW-QCD virtual corrections to Drell-Yan scattering
We present the calculation of the master integrals needed for the two-loop
QCDxEW corrections to and for massless external particles. We treat W and Z bosons
as degenerate in mass. We identify three types of diagrams, according to the
presence of massive internal lines: the no-mass type, the one-mass type, and
the two-mass type, where all massive propagators, when occurring, contain the
same mass value. We find a basis of 49 master integrals and evaluate them with
the method of the differential equations. The Magnus exponential is employed to
choose a set of master integrals that obeys a canonical system of differential
equations. Boundary conditions are found either by matching the solutions onto
simpler integrals in special kinematic configurations, or by requiring the
regularity of the solution at pseudo-thresholds. The canonical master integrals
are finally given as Taylor series around d=4 space-time dimensions, up to
order four, with coefficients given in terms of iterated integrals,
respectively up to weight four.Comment: 1+45 pages, 6 figures, 1 table, 5 ancillary file
Off-shell Currents and Color-Kinematics Duality
We elaborate on the color-kinematics duality for off-shell diagrams in gauge
theories coupled to matter, by investigating the scattering process , and show that the Jacobi relations for the kinematic numerators
of off-shell diagrams, built with Feynman rules in axial gauge, reduce to a
color-kinematics violating term due to the contributions of sub-graphs only.
Such anomaly vanishes when the four particles connected by the Jacobi relation
are on their mass shell with vanishing squared momenta, being either external
or cut particles, where the validity of the color-kinematics duality is
recovered. We discuss the role of the off-shell decomposition in the direct
construction of higher-multiplicity numerators satisfying color-kinematics
identity in four as well as in dimensions, for the latter employing the
Four Dimensional Formalism variant of the Four Dimensional Helicity scheme. We
provide explicit examples for the QCD process .Comment: Accepted version for publication in PLB. Manuscript extended: 19
pages, 15 figures; C/K duality for tree-level amplitudes in dimensional
regularization added; references added; title modifie
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