Global exponential stability of classical solutions to the hydrodynamic model for semiconductors

In this paper, the global well-posedness and stability of classical solutions to the multidimensional hydrodynamic model for semiconductors on the framework of Besov space are considered. We weaken the regularity requirement of the initial data, and improve some known results in Sobolev space. The local existence of classical solutions to the Cauchy problem is obtained by the regularized means and compactness argument. Using the high- and low- frequency decomposition method, we prove the global exponential stability of classical solutions (close to equilibrium). Furthermore, it is also shown that the vorticity decays to zero exponentially in the 2D and 3D space. The main analytic tools are the Littlewood-Paley decomposition and Bony's para-product formula.Comment: 18 page

A survey of cost-sensitive decision tree induction algorithms

The past decade has seen a significant interest on the problem of inducing decision trees that take account of costs of misclassification and costs of acquiring the features used for decision making. This survey identifies over 50 algorithms including approaches that are direct adaptations of accuracy based methods, use genetic algorithms, use anytime methods and utilize boosting and bagging. The survey brings together these different studies and novel approaches to cost-sensitive decision tree learning, provides a useful taxonomy, a historical timeline of how the field has developed and should provide a useful reference point for future research in this field

How the Noninflammasome NLRs Function in the Innate Immune System

NLR (nucleotide-binding domain, leucine-rich repeat containing) proteins have rapidly emerged as central regulators of immunity and inflammation with demonstrated relevance to human diseases. Much attention has focused on the ability of several NLRs to activate the inflammasome complex and drive proteolytic processing of inflammatory cytokines; however, NLRs also regulate important inflammasome-independent functions in the immune system. In this review, we will discuss several of these functions, including the regulation of canonical and non-canonical NF-κB activation, MAP kinase activation, cytokine and chemokine production, antimicrobial reactive oxygen species production, type I interferon production, and RNase L activity. We will also explore the mechanistic basis of these functions and present current challenges in the field

Class II Transactivator: Mastering the Art of Major Histocompatibility Complex Expression

Great progress in understanding the relative importance of various portions of CIITA for transcriptional activation of class II MHC genes has been made since CIITA's discovery in 1993. Emerging from these studies is a fairly consistent picture where CIITA is expressed, binds GTP, translocates to the nucleus, and interacts with specific DNA-binding transcription factors and basal transcription components, thus opening and activating class II MHC and related promoters. Despite these strides, this model is essentially unchanged from that initially espoused. The observation that class II MHC promoters in some B cells are bound to X and Y box binding proteins and thus open even in the absence of CIITA, whereas these same promoters in non-B cells are closed until CIITA is present, is provocative. One potential explanation is that CIITA possesses two distinct functions, the ability to direct the opening of responsive promoters (presumably through some form of remodeling) and the ability to activate transcription through its activation domain and protein-protein interactions (132, 141). The presence of a locus control region responsive to a B-cell-specific factor is another possibility, yet CIITA must, in some fashion, be directing chromatin remodeling in cells which can be induced to express CIITA. While CBP is an obvious candidate for mediating remodeling, no conclusive experiments have shown that CBP is required for the remodeling of class II MHC promoters. The studies above support interactions between CIITA and transcription factors, but does CIITA merely bind these factors to place the activation domain appropriately? Why has it been difficult to demonstrate a role for CIITA in a transcription complex? Is GTP binding only essential for nuclear import? Is nuclear export of CIITA occurring and is it relevant? What aspect of class II MHC transcription requires that retinoblastoma protein Rb be present? Is CIITA a prototype for a family of transcriptional coactivators? Why is limited class II expression observed in the absence of CIITA? The evolutionary conservation of W-, X-, and Y-containing promoters in mammals, birds (104), amphibians (51), and fish (121) suggests that CIITA may be extremely old; what are its origins? All remaining questions aside, CIITA is truly a remarkable protein. Controlled by up to four separate promoters, CIITA has been imparted a complex pattern of inducible and constitutive expression that can be regulated in developmental pathways. Through exercising specific control over the transcription of every major component of class II MHC antigen presentation pathway, CIITA gains the title of a master regulator. As CIITA appears to be class II MHC specific, it can be thought of as the core transcription factor of which all the remaining components are but cofactors. This is central to the concept of CIITA as a scaffolding protein or integrator and perhaps alters our view of transcriptional control away from promoters and individual factors towards a more unified enhanceosome perspective. The view of CIITA as a master regulator has implications for practical applications that are staggering. Successful engineering of dominant-negative CIITAs may lead to the production of transplant tissues unable to express class II MHC and the associated self peptides which contribute so significantly to graft rejection. A thorough understanding of CIITA's molecular mechanisms may lead to therapeutics which allow temporary enhancement or suppression of class II MHC, thus favorably altering the immune response during critical events in pathogenesis, autoimmune disease, tumorigenesis, and neuroinflammation

Vortex solutions in axial or chiral coupled non-relativistic spinor- Chern-Simons theory

The interaction of a spin 1/2 particle (described by the non-relativistic "Dirac" equation of L\'evy-Leblond) with Chern-Simons gauge fields is studied. It is shown, that similarly to the four dimensional spinor models, there is a consistent possibility of coupling them also by axial or chiral type currents. Static self dual vortex solutions together with a vortex-lattice are found with the new couplings.Comment: Plain TEX, 10 page

A Survey on Approximation Mechanism Design without Money for Facility Games

In a facility game one or more facilities are placed in a metric space to serve a set of selfish agents whose addresses are their private information. In a classical facility game, each agent wants to be as close to a facility as possible, and the cost of an agent can be defined as the distance between her location and the closest facility. In an obnoxious facility game, each agent wants to be far away from all facilities, and her utility is the distance from her location to the facility set. The objective of each agent is to minimize her cost or maximize her utility. An agent may lie if, by doing so, more benefit can be obtained. We are interested in social choice mechanisms that do not utilize payments. The game designer aims at a mechanism that is strategy-proof, in the sense that any agent cannot benefit by misreporting her address, or, even better, group strategy-proof, in the sense that any coalition of agents cannot all benefit by lying. Meanwhile, it is desirable to have the mechanism to be approximately optimal with respect to a chosen objective function. Several models for such approximation mechanism design without money for facility games have been proposed. In this paper we briefly review these models and related results for both deterministic and randomized mechanisms, and meanwhile we present a general framework for approximation mechanism design without money for facility games

B\"{a}cklund transformations for the KP and mKP hierarchies with self-consistent sources

Using gauge transformations for the corresponding generating pseudo-differential operators $L^n$ in terms of eigenfunctions and adjoint eigenfunctions, we construct several types of auto-B\"{a}cklund transformations for the KP hierarchy with self-consistent sources (KPHSCS) and mKP hierarchy with self-consistent sources (mKPHSCS) respectively. The B\"{a}cklund transformations from the KPHSCS to mKPHSCS are also constructed in this way.Comment: 22 pages. to appear in J.Phys.

Essential Role of the Cooperative Lattice Distortion in the Charge, Orbital and Spin Ordering in doped Manganites

The role of lattice distortion in the charge, orbital and spin ordering in half doped manganites has been investigated. For fixed magnetic ordering, we show that the cooperative lattice distortion stabilize the experimentally observed ordering even when the strong on-site electronic correlation is taken into account. Furthermore, without invoking the magnetic interactions, the cooperative lattice distortion alone may lead to the correct charge and orbital ordering including the charge stacking effect, and the magnetic ordering can be the consequence of such a charge and orbital ordering. We propose that the cooperative nature of the lattice distortion is essential to understand the complicated charge, orbital and spin ordering observed in doped manganites.Comment: 5 pages,4 figure

Scaling of Anisotropic Flows and Nuclear Equation of State in Intermediate Energy Heavy Ion Collisions

Elliptic flow ($v_2$) and hexadecupole flow ($v_4$) of light clusters have been studied in details for 25 MeV/nucleon $^{86}$Kr + $^{124}$Sn at large impact parameters by Quantum Molecular Dynamics model with different potential parameters. Four parameter sets which include soft or hard equation of state (EOS) with/without symmetry energy term are used. Both number-of-nucleon ($A$) scaling of the elliptic flow versus transverse momentum ($p_t$) and the scaling of $v_4/A^{2}$ versus $(p_t/A)^2$ have been demonstrated for the light clusters in all above calculation conditions. It was also found that the ratio of $v_4/{v_2}^2$ keeps a constant of 1/2 which is independent of $p_t$ for all the light fragments. By comparisons among different combinations of EOS and symmetry potential term, the results show that the above scaling behaviors are solid which do not depend the details of potential, while the strength of flows is sensitive to EOS and symmetry potential term.Comment: 5 pages, 5 figure