Hadronic final state predictions from CCFM: the hadron-level Monte Carlo generator CASCADE

We discuss a practical formulation of backward evolution for the CCFM small-$x$ evolution equation and show results from its implementation in the new Monte Carlo event-generator CASCADE.Comment: 20 pages, 8 figure

The influence of the environmental factors on the adoption of the International Accounting System IAS/IFRS : case of Iraq

Purpose: This research aims to study the impact of local environmental factors on the adoption of International Accounting system in Iraq. So the main objective of the research can be the evaluation of the role of local environmental factors in selecting the best method to adopt International Accounting Standards (IAS), and International Financial Reporting Standards (IFRS). Design/methodology/approach: The researchers prepared a questionnaire contains 28 paragraphs which were coded and divided into 7 parts showing the independent variables of the study (the environmental factors) and the dependent variable (the adoption of IAS/IFRS) Findings: The results of the research show that the local environment factors can effect on the choice of the country to adopt the best method of IAS/IFRS adoption, and the statistical analysis results show that there is a very good level of agreement for the participants about the effect of local environment factors on the adoption of IAS/IFRS. Practical implications: The research offers insights to the need to activate national standards and principles that are appropriate to the local environment in order to adapt with the requirements of IAS/IFRS adoption. Originality/value: The research presents significant pragmatic evidence in terms of its meticulous approach towards checking the robustness of results.peer-reviewe

Casimir-Polder intermolecular forces in minimal length theories

Generalized uncertainty relations are known to provide a minimal length $\hbar\sqrt{\beta}$. The effect of such minimal length in the Casimir-Polder interactions between neutral atoms (molecules) is studied. The first order correction term in the minimal uncertainty parameter is derived and found to describe an attractive potential scaling as $r^{-9}$ as opposed to the well known $r^{-7}$ long range retarded potential.Comment: 1 Figure. Version published by Physical Review D. Few references added, typos correcte

Role of the K1K_1 meson in K0K^0 photoproduction off the deuteron

Neutral kaon photoproduction off the nucleon and deuteron has been reinvestigated by utilizing the new experimental data on both targets. An isobar model for elementary operator and impulse approximation for the reaction on the deuteron have been used. The available free parameters in the elementary model have been extracted from both elementary and deuteron data. In contrast to the elementary reaction, fitting the deuteron data requires an inclusion of weighting factor. The result indicates that the angular distribution of the elementary $K^0\Lambda$ process does not show backward peaking behavior.Comment: 4 pages, 4 figures, prepared for the Fifth Asia-Pacific Conference on Few-Body Problems in Physics 2011 (APFB2011), Seoul, Korea, August 22-26, 201

Quark mass hierarchy in 3-3-1 models

We study the mass spectrum of the quark sector in an special type I-like model with gauge symmetry $SU(3)_c \otimes SU(3)_L \otimes U(1)_X$. By considering couplings with scalar triplets at large ($\sim TeV$) and small ($\sim GeV$) scales, we obtain specific zero-texture mass matrices for the quarks which predict three massless quarks ($u,d,s$) and three massive quarks ($c,b,t$) at the electroweak scale ($\sim$ GeV). Taking into account mixing couplings with three heavy quarks at large scales predicted by the model, the three massless quarks obtain masses at small order that depends on the inverse of the large scale. Thus, masses of the form $m_u \lesssim m_d < m_s \sim MeV$ and $m_{c,b,t} \sim GeV$ can be obtained naturally from the gauge structure of the model

Comparing effects of interleukin-2 and interleukin-4 on the expression of MHC class II, CD80 and CD86 on polymorphonuclear neutrophils

Polymorphonuclear neutrophils (PMN) have contributed only to the innate immune response, due to their phagocytosis activity. They have a short life time. Some studies of PMN cytokine production and expression of numerous cell surface proteins have suggested that PMN are likely to influence adaptive responses and may satisfy the criteria of antigen presenting cells. Flowcytometry was used in the present study for the detection of cell surface major histocompatibility complex (MHC) class II, CD80 and CD86 required for antigen presentation and subsequent T-cell activation. Human peripheral blood neutrophils were used for this purpose. In vitro stimulation ofPMN with IL-2 or IL-4 for 24 h showed expression of MHC class II, CD80 and CD86. These observations, therefore, provide support to the hypothesis that human PMN have the potential to express molecules required for antigen presentation

External Inversion, Internal Inversion, and Reflection Invariance

Having in mind that physical systems have different levels of structure we develop the concept of external, internal and total improper Lorentz transformation (space inversion and time reversal). A particle obtained from the ordinary one by the application of internal space inversion or time reversal is generally a different particle. From this point of view the intrinsic parity of a nuclear particle (`elementary particle') is in fact the external intrinsic parity, if we take into account the internal structure of a particle. We show that non-conservation of the external parity does not necessarily imply non-invariance of nature under space inversion. The conventional theory of beta-decay can be corrected by including the internal degrees of freedom to become invariant under total space inversion, though not under the external one.Comment: 15 pages. An early proposal of "mirror matter", published in 1974. This is an exact copy of the published paper. I am posting it here because of the increasing interest in the "exact parity models" and its experimental consequence