106 research outputs found
An Etude on Recursion Relations and Triangulations
Following~\cite{Arkani-Hamed:2017thz}, we derive a recursion relation by
applying a one-parameter deformation of kinematic variables for tree-level
scattering amplitudes in bi-adjoint theory. The recursion relies on
properties of the amplitude that can be made manifest in the underlying
kinematic associahedron, and it provides triangulations for the latter.
Furthermore, we solve the recursion relation and present all-multiplicity
results for the amplitude: by reformulating the associahedron in terms of its
vertices, it is given explicitly as a sum of "volume" of simplicies for any
triangulation, which is an analogy of BCFW representation/triangulation of
amplituhedron for SYM.Comment: 26 pages, 3 figure
An Etude on Recursion Relations and Triangulations
Following~\cite{Arkani-Hamed:2017thz}, we derive a recursion relation by
applying a one-parameter deformation of kinematic variables for tree-level
scattering amplitudes in bi-adjoint theory. The recursion relies on
properties of the amplitude that can be made manifest in the underlying
kinematic associahedron, and it provides triangulations for the latter.
Furthermore, we solve the recursion relation and present all-multiplicity
results for the amplitude: by reformulating the associahedron in terms of its
vertices, it is given explicitly as a sum of "volume" of simplicies for any
triangulation, which is an analogy of BCFW representation/triangulation of
amplituhedron for SYM.Comment: 26 pages, 3 figure
Notes on cluster algebras and some all-loop Feynman integrals
We study cluster algebras for some all-loop Feynman integrals, including
box-ladder, penta-box-ladder, and (seven-point) double-penta-ladder integrals.
In addition to the well-known box ladder whose symbol alphabet is , we show that penta-box ladder has an alphabet of and
provide strong evidence that the alphabet of double-penta ladder can be
identified with a cluster algebra. We relate the symbol letters to the
variables of cluster configuration space, which provide a
gauge-invariant description of the cluster algebra, and we find various
sub-algebras associated with limits of the integrals. We comment on constraints
similar to extended-Steinmann relations or cluster adjacency conditions on
cluster function spaces. Our study of the symbol and alphabet is based on the
recently proposed Wilson-loop representation, which allows us to
predict higher-loop alphabet recursively; by applying such recursions to
six-dimensional hexagon integrals, we also find and cluster
functions for the two-mass-easy and three-mass-easy case, respectively.Comment: 28 pages, several figures; v2: typos corrected, functions of ladder
integrals computed to higher loops; v3: more examples of double-penta-ladder
integrals and discussions about their alphabet adde
Bootstrapping octagons in reduced kinematics from cluster algebras
Multi-loop scattering amplitudes/null polygonal Wilson loops in super-Yang-Mills are known to simplify significantly in reduced
kinematics, where external legs/edges lie in an dimensional subspace of
Minkowski spacetime (or boundary of the subspace). Since the edges
of a -gon with even and odd labels go along two different null directions,
the kinematics is reduced to two copies of . In the
simplest octagon case, we conjecture that all loop amplitudes and Feynman
integrals are given in terms of two overlapping functions (a special case
of two-dimensional harmonic polylogarithms): in addition to the letters of , there are two letters mixing
the two sectors but they never appear together in the same term; these are the
reduced version of four-mass-box algebraic letters. Evidence supporting our
conjecture includes all known octagon amplitudes as well as new computations of
multi-loop integrals in reduced kinematics. By leveraging this alphabet and
conditions on first and last entries, we initiate a bootstrap program in
reduced kinematics: within the remarkably simple space of overlapping
functions, we easily obtain octagon amplitudes up to two-loop NMHV and
three-loop MHV. We also briefly comment on the generalization to -gons in
terms of functions and beyond.Comment: 26 pages, several figures and tables, an ancilary fil
Feynman Integrals and Scattering Amplitudes from Wilson Loops
We study Feynman integrals and scattering amplitudes in
super-Yang-Mills by exploiting the duality with null polygonal Wilson loops.
Certain Feynman integrals, including one-loop and two-loop chiral pentagons,
are given by Feynman diagrams of a supersymmetric Wilson loop, where one can
perform loop integrations and be left with simple integrals along edges. As the
main application, we compute analytically for the first time, the symbol of the
generic () double pentagon, which gives two-loop MHV amplitudes and
components of NMHV amplitudes to all multiplicities. We represent the double
pentagon as a two-fold integral of a one-loop hexagon, and
the non-trivial part of the integration lies at rationalizing square roots
contained in the latter. We obtain a remarkably compact "algebraic words" which
contain algebraic letters for each of the square roots, and they all
nicely cancel in combinations for MHV amplitudes and NMHV components which are
free of square roots. In addition to algebraic letters, the alphabet
consists of dual conformal invariant combinations of rational letters.Comment: 8 pages, 4 figures, 1 ancillary file; v3: important updates, a
compact form for the symbol of double pentagon integral added; typos
correcte
On symbology and differential equations of Feynman integrals from Schubert analysis
We take the first step in generalizing the so-called "Schubert analysis",
originally proposed in twistor space for four-dimensional kinematics, to the
study of symbol letters and more detailed information on canonical differential
equations for Feynman integral families in general dimensions with general
masses. The basic idea is to work in embedding space and compute possible
cross-ratios built from (Lorentz products of) maximal cut solutions for all
integrals in the family. We demonstrate the power of the method using the most
general one-loop integrals, as well as various two-loop planar integral
families (such as sunrise, double-triangle and double-box) in general
dimensions. Not only can we obtain all symbol letters as cross-ratios from
maximal-cut solutions, but we also reproduce entries in the canonical
differential equations satisfied by a basis of dlog integrals.Comment: 51 pages, many figure
Chidamide and Decitabine in Combination with a HAG Priming Regimen for Acute Myeloid Leukemia with TP53 Mutation
We analyzed the treatment effects of chidamide and decitabine in combination with a HAG (homoharringtonine, cytarabine, G-CSF) priming regimen (CDHAG) in acute myeloid leukemia (AML) patients with TP53 mutation. Seven TP53 mutated AML patients were treated with CDHAG. The treatment effects were assessed using hemogram detection and bone marrow aspirate. The possible side effects were evaluated based on both hematological and non-hematological toxicity. Four of the seven patients were classified as having achieved complete remission after CDHAG treatment; one patient was considered to have achieved partial remission, and the remaining two patients were considered in non-remission. The overall response rate (ORR) to CDHAG was 71.4%. Regarding the side effects, the hematological toxicity level of the seven patients ranged from level III to level IV, and infections that occurred at lung, blood, and skin were recorded. Nausea, vomiting, liver injury, and kidney injury were also detected. However, all side effects were attenuated by proper management. The CDHAG regimen clearly improved the ORR (71.4%) of TP53-mutated AML patients, with no severe side effects
MCP-induced protein 1 deubiquitinates TRAF proteins and negatively regulates JNK and NF-κB signaling
A previously unappreciated deubiquitinase activity of MCP-induced protein 1 contributes to its role in dampening inflammatory signaling
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