Double-resonant fast particle-wave interaction

In future fusion devices fast particles must be well confined in order to transfer their energy to the background plasma. Magnetohydrodynamic instabilities like Toroidal Alfv\'en Eigenmodes or core-localized modes such as Beta Induced Alfv\'en Eigenmodes and Reversed Shear Alfv\'en Eigenmodes, both driven by fast particles, can lead to significant losses. This is observed in many ASDEX Upgrade discharges. The present study applies the drift-kinetic HAGIS code with the aim of understanding the underlying resonance mechanisms, especially in the presence of multiple modes with different frequencies. Of particular interest is the resonant interaction of particles simultaneously with two different modes, referred to as 'double-resonance'. Various mode overlapping scenarios with different q profiles are considered. It is found that, depending on the radial mode distance, double-resonance is able to enhance growth rates as well as mode amplitudes significantly. Surprisingly, no radial mode overlap is necessary for this effect. Quite the contrary is found: small radial mode distances can lead to strong nonlinear mode stabilization of a linearly dominant mode.Comment: 12 pages, 11 figures; Nuclear Fusion 52 (2012

Interplay between cell adhesion and growth factor receptors: from the plasma membrane to the endosomes

The emergence of multicellular animals could only take place once evolution had produced molecular mechanisms for cell adhesion and communication. Today, all metazoans express integrin-type adhesion receptors and receptors for growth factors. Integrins recognize extracellular matrix proteins and respective receptors on other cells and, following ligand binding, can activate the same cellular signaling pathways that are regulated by growth factor receptors. Recent reports have indicated that the two receptor systems also collaborate in many other ways. Here, we review the present information concerning the role of integrins as assisting growth factor receptors and the interplay between the receptors in cell signaling and in the orchestration of receptor recycling

De novo characterization of the gametophyte transcriptome in bracken fern, Pteridium aquilinum

<p>Abstract</p> <p>Background</p> <p>Because of their phylogenetic position and unique characteristics of their biology and life cycle, ferns represent an important lineage for studying the evolution of land plants. Large and complex genomes in ferns combined with the absence of economically important species have been a barrier to the development of genomic resources. However, high throughput sequencing technologies are now being widely applied to non-model species. We leveraged the Roche 454 GS-FLX Titanium pyrosequencing platform in sequencing the gametophyte transcriptome of bracken fern (<it>Pteridium aquilinum</it>) to develop genomic resources for evolutionary studies.</p> <p>Results</p> <p>681,722 quality and adapter trimmed reads totaling 254 Mbp were assembled <it>de novo </it>into 56,256 unique sequences (i.e. unigenes) with a mean length of 547.2 bp and a total assembly size of 30.8 Mbp with an average read-depth coverage of 7.0×. We estimate that 87% of the complete transcriptome has been sequenced and that all transcripts have been tagged. 61.8% of the unigenes had blastx hits in the NCBI nr protein database, representing 22,596 unique best hits. The longest open reading frame in 52.2% of the unigenes had positive domain matches in InterProScan searches. We assigned 46.2% of the unigenes with a GO functional annotation and 16.0% with an enzyme code annotation. Enzyme codes were used to retrieve and color KEGG pathway maps. A comparative genomics approach revealed a substantial proportion of genes expressed in bracken gametophytes to be shared across the genomes of <it>Arabidopsis</it>, <it>Selaginella </it>and <it>Physcomitrella</it>, and identified a substantial number of potentially novel fern genes. By comparing the list of <it>Arabidopsis </it>genes identified by blast with a list of gametophyte-specific <it>Arabidopsis </it>genes taken from the literature, we identified a set of potentially conserved gametophyte specific genes. We screened unigenes for repetitive sequences to identify 548 potentially-amplifiable simple sequence repeat loci and 689 expressed transposable elements.</p> <p>Conclusions</p> <p>This study is the first comprehensive transcriptome analysis for a fern and represents an important scientific resource for comparative evolutionary and functional genomics studies in land plants. We demonstrate the utility of high-throughput sequencing of a normalized cDNA library for <it>de novo </it>transcriptome characterization and gene discovery in a non-model plant.</p

PbTiO3PbTiO_3 nanoparticle precursors for chemical solution deposited electroceramic thin films

The Vascular Registry (VR) on carotid procedures collects long-term outcomes on carotid artery stenting (CAS) and carotid endarterectomy (CEA) patients. The purpose of this report is to describe in-hospital and 30-day CAS outcomes in patients with atherosclerotic carotid artery disease (CAD; atherosclerosis [ATH]) compared to recurrent carotid stenosis (RES) and radiation-induced stenosis (RAD).The VR collects provider-reported data on CAS using a Web-based data management system. For this report, data were analyzed at the preprocedure, procedure, predischarge, and 30-day intervals.As of November 20, 2008, there were 4017 patients with CAS with discharge data, of which 72% were due to ATH. A total of 2321 patients were available for 30-day outcomes analysis (1623 ATH, 529 restenosis, 119 radiation, 17 dissection, 3 trauma, and 30 other). Baseline demographics showed that ATH occurred in older patients (72-years-old), had the greatest history of coronary artery disease (CAD; 62%), myocardial infarction (MI; 24%), valvular heart disease (8%), arrhythmia (16%), congestive heart failure (CHF; 16%), diabetes mellitus (DM; 35%), and chronic obstructive pulmonary disease (COPD; 20%). RES had a higher degree of baseline stenosis (87.0 vs 85.8 ATH; P = .010), were less likely to be symptomatic (35.5% vs 46.3% ATH; P < .001), but had a greater history of hypertension, peripheral vascular disease (PVD), and smoking. RAD was seen in younger patients (66.6 vs 71.7 ATH; P < .001), were more likely to be male (78.2% vs 60.9% ATH; P < .001), and had less comorbidities overall, with the exception of amaurosis fugax, smoking, and cancer. The only statistically significant difference in perioperative rates was in transient ischemic attack (TIA; 2.7% ATH vs 0.9% RES; P = .02). There were no statistically significant differences in in-hospital death/stroke/MI (ATH 5.4%, RES 3.8%, RAD 4.2%) or at 30 days (ATH 7.1%, RES 5.1%, RAD 5.0%). Even after adjusting for age, gender, symptomatology, CHF, and renal failure, the only statistically significant difference at 30 days was amaurosis fugax between ATH and RAD (odds ratio [OR] 0.13; P = .01).Although patients with ATH have statistically significant comorbidities, they did not have statistically significant increased rates of death/stroke/MI during hospitalization or within 30 days after discharge when compared to RES or RAD. The CAS event rates for ATH vs RES and RAD are similar, despite prior published reports. Symptomatic ATH have statistically significant higher rates of death/stroke/MI compared to asymptomatic cohort. Finally, consistent and accurate entry of long-term data beyond initial hospitalization is essential to fully assess CAS outcomes since a significant number of adverse events occur in the interval from hospital discharge to 30 days

Increased Expression of Integrin αvβ5 Induces the Myofibroblastic Differentiation of Dermal Fibroblasts

The biological effect of cytokines is mainly determined by the cytokine-receptor interaction, which is modulated by the concentration and the activity of cytokines and/or their receptors. Because αv-containing integrins can bind to and/or activate latent TGF-β, these integrins have been thought to be involved in the pathogenesis of fibrotic disorders. Our recent observations that αvβ5 is up-regulated in scleroderma fibroblasts and that the transient overexpression of αvβ5 increases the human α2(I) collagen gene expression in normal fibroblasts suggest the involvement of αvβ5 in the self-activation system in scleroderma fibroblasts. In this study, we established stable transfectants with αvβ5 using normal dermal fibroblasts and demonstrated that such cells differentiated into myofibroblasts by the stimulation of autocrine TGF-β. This observation is explained by 1) αvβ5 recruiting latent TGF-β1 on the cell surface, 2) endogenous active TGF-β localizing on the cell surface, and 3) αvβ5 interacting with TGF-β receptors. Furthermore, blockade of αvβ5 reversed the myofibroblastic phenotype in scleroderma fibroblasts. These data identify a novel mechanism for the establishment of autocrine TGF-β signaling in dermal fibroblasts by the up-regulation of αvβ5 and suggest the possibility of regulating fibrotic disorders, especially scleroderma, by targeting this integrin