c-Jun N-Terminal Kinase in Inflammation and Rheumatic Diseases.

The c-Jun N-terminal kinases (JNKs) are members of the mitogen-activated protein kinase (MAPK) family and are activated by environmental stress. JNK is also activated by proinflammatory cytokines, such as TNF and IL-1, and Toll-like receptor ligands. This pathway, therefore, can act as a critical convergence point in immune system signaling for both adaptive and innate responses. Like other MAPKs, the JNKs are activated via the sequential activation of protein kinases that includes two dual-specificity MAP kinase kinases (MKK4 and MKK7) and multiple MAP kinase kinase kinases. MAPKs, including JNKs, can be deactivated by a specialized group of phosphatases, called MAP kinase phosphatases. JNK phosphorylates and regulates the activity of transcription factors other than c-Jun, including ATF2, Elk-1, p53 and c-Myc and non-transcription factors, such as members of the Bcl-2 family. The pathway plays a critical role in cell proliferation, apoptosis, angiogenesis and migration. In this review, an overview of the functions that are related to rheumatic diseases is presented. In addition, some diseases in which JNK participates will be highlighted

Knowledge Sharing and the Psychological Contract: Managing Knowledge Workers across Different Stages of Employment

Purpose – An employee’s willingness to share knowledge may be contingent on whether the organization equitably fulfills its reward obligations. This paper seeks to examine how managers and organizations can be vehicles for managing psychological contract perceptions favoring knowledge sharing among current employees, newcomers, and applicants. Design/methodology/approach – The authors propose an integrative model to discuss psychological contract issues within each stage of employment and HRM initiatives that can encourage knowledge-sharing behaviors. Findings – The implicit psychological contracts that often influence knowledge worker attitudes for sharing knowledge are easy to overlook and challenging to manage. Managers must properly assess the nature of psychological contracts maintained by such workers so that knowledge-sharing messages address employees’ key motivators. Different psychological contracts exist at various stages of employment. Several prescriptions for effectively managing each type of psychological contract and reducing perceptions of PC breach were offered. Research limitations/implications – Empirical studies should seek to investigate whether different psychological contracts actually exist within a field setting. In addition, how workers move between transitional, transactional, balanced and relational psychological contracts should be empirically examined. Originality/value – The authors sought to better understand the different psychological contract perceptions of knowledge workers at various stages of employment, which has not been done to date. Such workers are keenly aware of the impact of their knowledge and effective management for sharing rather than hoarding becomes a critical success factor for knowledge-intensive organizations

A study of the morphology, composition and mineral associations of Fe-Ni sulphides in CM carbonaceous chondrites

A study of the compositional and textural variations between Fe-Ni sulphides in a suite of pristine to extensively aqueously altered CM chondrites, using SEM and EMP techniques

Constant sign and nodal solutions for nonhomogeneous Robin boundary value problems with asymmetric reactions

We study a nonlinear, nonhomogeneous elliptic equation with an asymmetric reaction term depending on a positive parameter, coupled with Robin boundary conditions. Under appropriate hypotheses on both the leading differential operator and the reaction, we prove that, if the parameter is small enough, the problem admits at least four nontrivial solutions: two of such solutions are positive, one is negative, and one is sign-changing. Our approach is variational, based on critical point theory, Morse theory, and truncation techniques.Comment: 22 page

Steady flow of power-law fluids in a 1:3 planar sudden expansion

The laminar flow of inelastic non-Newtonian fluids, obeying the power-law model, through a planar sudden expansion with a 1:3 expansion ratio was investigated numerically using a finite volume method. A broad range of power-law indices in the range 0.2 n 4 was considered. Shear-thinning, Newtonian and shear-thickening fluids are analyzed, with particular emphasis on the flow patterns and bifurcation phenomenon occurring at high Reynolds number laminar flows. The effect of the generalized Reynolds numbers (based on power-law index, n, and the in flow channel height, h) on the main vortex characteristics and Couette correction are examined in detail in the range varying from 0.01 Regen 600. Values for the critical generalized Reynolds number for the onset of steady flow asymmetry and the appearance of a third main vortex are also included. We found that the shear-thinning behavior increases the critical Regen, while shear-thickening has the opposite effect. Comparison with available literature and with predictions using a commercial software (FluentR 6.3.26) are also presented and discussed. It was found that both results are in good agreement, but that our code is able to achieve converged solution for a broader range of flow conditions, providing new benchmark quality data

Galactic Evolution Of D And 3He Including Stellar Production Of 3He

New stellar models which track the production and destruction of $^3$He (and D) have been evolved for a range of stellar masses $(0.65\leq M/M_{\odot}\leq 100)$, metallicities $(0.01 \leq Z/Z_{\odot} \leq 1)$ and initial (main sequence) $^3$He mass fractions $(10^{-5} \leq X_{3,MS} \leq 10^{-3})$. Armed with the $^3$He yields from these stellar models we have followed the evolution of D and $^3$He using a variety of chemical evolution models with and without infall of primordial or processed material. Production of new $^3$He by the lower mass stars overwhelms any reasonable primordial contributions and leads to predicted abundances in the presolar nebula and/or the present interstellar medium in excess of the observationally inferred values. This result, which obtains even for zero primordial D and $^3$He, and was anticipated by Rood, Steigman \& Tinsley (1976), is insensitive to the choice of chemical evolution model; it is driven by the large $^3$He yields from low mass stars. In an attempt to ameliorate this problem we have considered a number of non-standard models in which the yields from low mass stars have been modified. Although several of these non-standard models may be consistent with the $^3$He data, they may be inconsistent with observations of $^{12}$C/$^{13}$C, $^{18}$O and, most seriously, the super-$^3$He rich planetary nebulae (Rood, Bania \& Wilson 1992). Even using the most extreme of these non-standard models (Hogan 1995), we obtain a generous upper bound to pre-galactic $^3$He: X$_{3P} \leq 3.2 \times10^{-5}$ which, nonetheless, leads to a stringent lower bound to the universal density of nucleons.Comment: 21 pages, plus 10 figures, accepted by Ap

Job Developer Types, Placement Practices and Outcomes Technical Report

Despite numerous employment initiatives, people with disabilities are significantly more likely to experience unemployment and consequently, reduced economic and social well-being and a dminished quality of life than their non disabled peers. In a recent national survey of employers, less than 14% of companies indicated that they actively recruit jobseekers with disabilities. Thus, the role of the job development professional is pivotal to helping job seekers with disabilities to find, secure and maintain employment. This research report examined the attitudes and beliefs of job development processionals articulated in a previous technical report by TransCen, Inc. and looked to further explore the relationship between the types, other personal characteristics and placement outcomes of the various job developer types

Spin and magnetism in old neutron stars

The thermal, spin and magnetic evolution of neutron stars in the old low mass binaries is first explored. Recycled to very short periods via accretion torques, the neutron stars lose their magnetism progressively. If accretion proceeds undisturbed for 100 Myrs these stars can rotate close to break up with periods far below the minimum observed of 1.558 ms. We investigate their histories using population synthesis models to show that a tail should exist in the period distribution below 1.558 ms. The search of these ultrafastly spinning neutron stars as pulsars can help discriminating among the various equations of state for nuclear matter, and can shed light into the physics of binary evolution. The evolution of isolated neutron stars in the Galaxy is explored beyond the pulsar phase. Moving through the tenuous interstellar medium, these old solitary neutron stars lose their rotational energy. Whether also their magnetism fades is still a mystery. A population synthesis model has revealed that only a tiny fraction of them is able to accrete from the interstellar medium, shining in the X-rays. There is the hope that these solitary stars will eventually appear as faint sources in the Chandra sky survey. This might give insight on the long term evolution of the magnetic field in isolated objects.Comment: 28 pages, 11 PostScript figures. To be published in "Physics of Neutron Star Interiors" (Lecture Notes in Physics), ed. D. Blaschke, N.K. Glendenning and A. Sedrakian (Springer, 2001