Supersymmetric Dark Matter and Lepton Flavor Violation

The MSSM is often augmented by heavy singlets, in order to account for neutrino masses via the seesaw mechanism. However, these singlets can significantly impact predictions for neutralino relic density via RG effects on the SUSY mass spectrum and the concomitant changes to annihilation and detection rates. We study the interplay between these RG-mediated neutrino sector effects on relic density and constraints from lepton flavor violation, in CMSSM/mSUGRA-like models using several different GUT-inspired schemes for choosing neutrino sector parameters and mixings. We find that these effects can be very important for predictions of LFV rates; proper consideration of the changes to relic density bounds alters the predicted LFV rates by factors from a few up to two orders of magnitude, depending on the location in parameter space. Surprisingly, our results indicate that a large neutrino Yukawa unification parameter Rν u = 3 is not ruled out by current LFV bounds as was commonly thought. We also discuss our code Isajet-M, a modification and extension of standard Isajet, which we used to solve the RGEs. Isajet-M handles both the neutrino and quark sectors in complex matrix form, integrates out all particles at their individual scales, and calculates the sparticle spectrum, neutrino masses and mixings, rates for LFV processes, contributions to (g-2)μ, and neutralino relic density and cross-sections

Ocular Brucellosis: A Brief Update

Brucellosis is a zoonotic disease of important health significance in endemic areas such as Iran. Brucellosis can affect any organ or system in the human body. Ocular involvement is rare and can lead to poor visual prognosis if not treated early. The most common ocular manifestation of brucellosis is uveitis, although any ocular structure can be involved. The diagnosis of ocular brucellosis is based on clinical examination as well as culture and serological tests. The classical treatment regimen includes doxycycline and rifampin. Early diagnosis and prompt treatment are effective in preventing blindness. Here we breifly review the manifestations, diagnostic tools, and treatment of ocular brucellosis

Hot Potatoes: The Merits and Demerits

The present study was firstly meant to review and study the main functions and applications of the Hot Potatoes program and further to identify its main features in terms of the development of various types of language tests and exercises. Secondly the study identified a number of deficiencies both in connection with the applications and the modality of the exercises it produces. The analysis revealed that although the program offers facility in creating different types of exercises together with teacher’s feedback that can be posted online for the ease of access, it is limited in some important areas such as providing interactive activities and synchronous feedback for the learners. Moreover, it was found that the efficiency and usefulness of this program to a great extent depends on the creativity and skills of the teacher who uses the program to create tests. Similarly, the language contents that the teacher uses can have a great influence on the effectiveness of the exercises developed by Hot Potatoes. Therefore, the program by itself gives no advantage in helping learners with their language learning practice and exposure, but only acts as a learning tool

Nitridation during oxidation as a challenge for Cr-based alloys and its mitigation by alloying

The high temperature behavior of pure chromium above 1000°C shows very interesting features such as vaporization, scale spallation and worst of all extreme nitridation when exposed to air. A detailed investigation of the different mechanisms can explain the wide range and controversial results given in the literature when the oxidation and its oxidation rates are reported for pure Chromium. Especially, the attack by nitridation deteriorates the mechanical properties by severe embrittlement. It also has a huge impact on the mass change during oxidation. To mitigate this embrittlement an alloying strategy is developed by the addition of silicon and germanium. The oxidation behavior of binary Cr-Si and ternary Cr-Ge-Si alloys at ultra-high temperatures (T=1200°C-1350°C) is reported (see also Figure 1) and the morphological evolution of the oxide scale and the metal subsurface zone was investigated using scanning electron microscopy, electron probe micro-analysis, and X-ray diffraction techniques. The A15-phase Cr3Si is shown to have a crucial influence on prevention of nitridation. During oxidation of a two phase Crss-Cr3Si system an A15 barrier develops in form of a continuous intermetallic layer underneath the surface. The in-situ formed barrier layers shown to be able to successfully prevent nitridation and the same time to improve the oxidation kinetics. Beyond that, ternary additions of Ge to the Cr-Si system strengthens this effect even more and significantly improves the oxidation kinetics of the chromium alloys at ultra-high temperatures to a level comparable to alumina formers (Figure 2). Please click Additional Files below to see the full abstract

Effect of sleep hygiene education on sleep quality in hemodialysis patients

Introduction: Sleep is referred a regular,recurring and easily revocable state of organism which is characterized by relative immobility and significant increase in response threshold to environmental stimuli sleep disorders are common among haemodialysis patients. Aim: The aim of this study was to investigate the effect of sleep hygiene education on sleep quality in haemodialysis patients. Materials and Methods: This study is a randomized controlled clinical trial. The participants of this study were 60 haemodialysis patients admitted to the Dialysis Center of Shahid Ayatollah Madani Hospital of Khoy,affiliated with the Urmia University of Medical Sciences. Sampling was done randomly and the partcipants were randomly divided into intervention group (30 patients) and control group (30 patients). Sleep quality of participants was measured before and after the intervention by Pittsburgh Sleep Quality Index (PSQI). Training process for sleep hygiene behaviours was presented to the participants face-toface. The data were analysed using SPSS 16. Results: A significant difference in the mean (standard deviation) score for PSQI (p<0.001) was observed before and after intervention in the intervention group,while in the control group,the difference was not significant (p=0.704),In addition,a significant difference was observed in the mean (standard deviation) score for PSQI between the two intervention and control groups after the educational intervention (p=0.034). Conclusion: Sleep hygiene education,alongside other approaches,is a low-cost,accessible,and practical method which can be implemented within a short period of tim

IGF-1 and PDGF-bb suppress IL-1β-induced cartilage degradation through down-regulation of NF-κB signaling: involvement of Src/PI-3K/AKT pathway.

Interleukin-1β (IL-1β) is a pro-inflammatory cytokine that plays a key role in the pathogenesis of osteoarthritis (OA). Growth factors (GFs) capable of antagonizing the catabolic actions of cytokines may have therapeutic potential in the treatment of OA. Herein, we investigated the potential synergistic effects of insulin-like growth factor (IGF-1) and platelet-derived growth factor (PDGF-bb) on different mechanisms participating in IL-1β-induced activation of nuclear transcription factor-κB (NF-κB) and apoptosis in chondrocytes. Primary chondrocytes were treated with IL-1β to induce dedifferentiation and co-treated with either IGF-1 or/and PDGF-bb and evaluated by immunoblotting and electron microscopy. Pretreatment of chondrocytes with IGF-1 or/and PDGF-bb suppressed IL-1β-induced NF-κB activation via inhibition of IκB-α kinase. Inhibition of IκB-α kinase by GFs led to the suppression of IκB-α phosphorylation and degradation, p65 nuclear translocation and NF-κB-regulated gene products involved in inflammation and cartilage degradation (COX-2, MMPs) and apoptosis (caspase-3). GFs or BMS-345541 (specific inhibitor of the IKK) reversed the IL-1β-induced down-regulation of collagen type II, cartilage specific proteoglycans, β1-integrin, Shc, activated MAPKinase, Sox-9 and up-regulation of active caspase-3. Furthermore, the inhibitory effects of IGF-1 or/and PDGF-bb on IL-1β-induced NF-κB activation were sensitive to inhibitors of Src (PP1), PI-3K (wortmannin) and Akt (SH-5), suggesting that the pathway consisting of non-receptor tyrosine kinase (Src), phosphatidylinositol 3-kinase and protein kinase B must be involved in IL-1β signaling. The results presented suggest that IGF-1 and PDGF-bb are potent inhibitors of IL-1β-mediated activation of NF-κB and apoptosis in chondrocytes, may be mediated in part through suppression of Src/PI-3K/AKT pathway, which may contribute to their anti-inflammatory effects