Search results for "4b"
showing 10 items of 72 documents
The Complement System: Activation and Control
1985
One of the hallmarks of immunology has been analysis and characterization of the C system in biological fluids. It is composed of 11 proteins of the “classical” pathway:1 C1q, C1r, C1s, C4, C2, C3, C5, C6, C7, C8, and C9. There are three proteins of the “alternative” pathway (IUIS-WHO Nomenclature Committee 1981) B, D, and P. Finally, there are four control proteins: C1 inhibitor (Cl¯ INH) and C4b binding protein (C4b-bp) for the classical pathway, I (C3b inactivator or C3b INA) and H (β1 or C3b INA accelerator) for the alternative pathway, and anaphylatoxin inactivator. Due to the dramatic advances in protein chemistry, these 19 distinct serum proteins have been highly purified and charact…
Multiplicity results for asymmetric boundary value problems with indefinite weights
2004
We prove existence and multiplicity of solutions, with prescribed nodal properties, to a boundary value problem of the formu″+f(t,u)=0,u(0)=u(T)=0. The nonlinearity is supposed to satisfy asymmetric, asymptotically linear assumptions involving indefinite weights. We first study some auxiliary half-linear, two-weighted problems for which an eigenvalue theory holds. Multiplicity is ensured by assumptions expressed in terms of weighted eigenvalues. The proof is developed in the framework of topological methods and is based on some relations between rotation numbers and weighted eigenvalues.
Histamine up-regulates phosphodiesterase 4 activity and reduces prostaglandin E2-inhibitory effects in human neutrophils.
2000
Objective: To investigate whether histamine produces up-regulation of phosphodiesterase (PDE) activity with functional consequences in human peripheral blood neutrophils.¶Methods: PDE activity was studied by a radioisotopic method following anion-exchange chromatography. Reverse transcriptase-polymerase chain reaction (RT-PCR) was used for detection of mRNA transcripts of PDE4 subtypes. Cyclic AMP (cAMP) levels were measured by enzyme-immunoassay, and superoxide generation by cytochrome c reduction.¶Treatment: Neutrophils were incubated for 4 h with histamine (1 μM).¶Results: PDE4 was the only isoenzyme activity increased in treated neutrophils. Kinetic analysis showed a ∼1.5-fold increase …
Recovering a variable exponent
2021
We consider an inverse problem of recovering the non-linearity in the one dimensional variable exponent $p(x)$-Laplace equation from the Dirichlet-to-Neumann map. The variable exponent can be recovered up to the natural obstruction of rearrangements. The main technique is using the properties of a moment problem after reducing the inverse problem to determining a function from its $L^p$-norms.
Families of solutions to the KPI equation and the structure of their rational representations of order N
2018
We construct solutions to the Kadomtsev-Petviashvili equation (KPI) in terms of Fredholm determinants. We deduce solutions written as a quotient of wronskians of order 2N. These solutions called solutions of order N depend on 2N − 1 parameters. They can also be written as a quotient of two polynomials of degree 2N (N + 1) in x, y and t depending on 2N − 2 parameters. The maximum of the modulus of these solutions at order N is equal to 2(2N + 1) 2. We explicitly construct the expressions until the order 6 and we study the patterns of their modulus in the plane (x, y) and their evolution according to time and parameters.
Algebraic singularities have maximal reductive automorphism groups
1989
LetX = On/ibe an analytic singularity where ṫ is an ideal of theC-algebraOnof germs of analytic functions on (Cn, 0). Letdenote the maximal ideal ofXandA= AutXits group of automorphisms. An abstract subgroupequipped with the structure of an algebraic group is calledalgebraic subgroupofAif the natural representations ofGon all “higher cotangent spaces”are rational. Letπbe the representation ofAon the first cotangent spaceandA1=π(A).
Increased dosage of Ink4/Arf protects against glucose intolerance and insulin resistance associated with aging
2013
Recent genome-wide association studies have linked type-2 diabetes mellitus to a genomic region in chromosome 9p21 near the Ink4/Arf locus, which encodes tumor suppressors that are up-regulated in a variety of mammalian organs during aging. However, it is unclear whether the susceptibility to type-2 diabetes is associated with altered expression of the Ink4/Arf locus. In the present study, we investigated the role of Ink4/Arf in age-dependent alterations of insulin and glucose homeostasis using Super-Ink4/Arf mice which bear an extra copy of the entire Ink4/Arf locus. We find that, in contrast to age-matched wild-type controls, Super-Ink4/Arf mice do not develop glucose intolerance with agi…
8-parameter solutions of fifth order to the Johnson equation
2019
We give different representations of the solutions of the Johnson equation with parameters. First, an expression in terms of Fredholm determinants is given; we give also a representation of the solutions written as a quotient of wronskians of order 2N. These solutions of order N depend on 2N − 1 parameters. When one of these parameters tends to zero, we obtain N order rational solutions expressed as a quotient of two polyno-mials of degree 2N (N +1) in x, t and 4N (N +1) in y depending on 2N −2 parameters. Here, we explicitly construct the expressions of the rational solutions of order 5 depending on 8 real parameters and we study the patterns of their modulus in the plane (x, y) and their …
From first to fourth order rational solutions to the Boussinesq equation
2020
Rational solutions to the Boussinesq equation are constructed as a quotient of two polynomials in x and t. For each positive integer N , the numerator is a polynomial of degree N (N + 1) − 2 in x and t, while the denominator is a polynomial of degree N (N + 1) in x and t. So we obtain a hierarchy of rational solutions depending on an integer N called the order of the solution. We construct explicit expressions of these rational solutions for N = 1 to 4.
Shape identification in inverse medium scattering problems with a single far-field pattern
2016
Consider time-harmonic acoustic scattering from a bounded penetrable obstacle $D\subset {\mathbb R}^N$ embedded in a homogeneous background medium. The index of refraction characterizing the material inside $D$ is supposed to be Holder continuous near the corners. If $D\subset {\mathbb R}^2$ is a convex polygon, we prove that its shape and location can be uniquely determined by the far-field pattern incited by a single incident wave at a fixed frequency. In dimensions $N \geq 3$, the uniqueness applies to penetrable scatterers of rectangular type with additional assumptions on the smoothness of the contrast. Our arguments are motivated by recent studies on the absence of nonscattering waven…