Quench Propagation in the Superconducting 6 kA Flexible Busbars of the LHC

Flexible superconducting cables with currents up to 6 kA will be used to power magnets individually in the insertion regions of the LHC. In case of a quench, the currents in these circuits will decay very fast (with time constants of about 200 ms) such that relatively small copper cross sections are sufficient for these busbars. Quench propagation experiments on a prototype cable and corresponding simulations led to a detailed understanding of the quench behavior of these busbars and to recommendations for the design and application of the cable. Simulations of the quench process in a multi-strand conductor led to a detailed understanding of the way current crosses from superconducting to pure copper strands and how this affects the quench propagation velocity. At nominal current (6 kA), the quench propagation velocities are high (10 m/s) and the hot spot temperature increases rapidly. In this situation, timely quench detection and energy extraction (current reduction) are vital to prevent damage of circuit components

Dynamics of macrophage polarization reveal new mechanism to inhibit IL-1β release through pyrophosphates

In acute inflammation, extracellular ATP activates P2X7 ion channel receptors (P2X7R) on M1 polarized macrophages to release pro-inflammatory IL-1β through activation of the caspase-1/nucleotide-binding domain and leucine-rich repeat receptor containing pyrin domain 3 (NLRP3) inflammasome. In contrast, M2 polarized macrophages are critical to the resolution of inflammation but neither actions of P2X7R on these macrophages nor mechanisms by which macrophages switch from pro-inflammatory to anti-inflammatory phenotypes are known. Here, we investigated extracellular ATP signalling over a dynamic macrophage polarity gradient from M1 through M2 phenotypes. In macrophages polarized towards, but not at, M2 phenotype, in which intracellular IL-1β remains high and the inflammasome is intact, P2X7R activation selectively uncouples to the NLRP3-inflammasome activation but not to upstream ion channel activation. In these intermediate M1/M2 polarized macrophages, extracellular ATP now acts through its pyrophosphate chains, independently of other purine receptors, to inhibit IL-1β release by other stimuli through two independent mechanisms: inhibition of ROS production and trapping of the inflammasome complex through intracellular clustering of actin filaments

Resposta da cultura do feijoeiro à adubação nitrogenada e à inoculação com rizóbio.

bitstream/item/67364/1/34249.pdfOrganizado por: Fábio Martins Mercante e Oscar Fontão de Lima Filho. RELARE

Isolamento e seleção de rizóbios de solos de Mato Grosso Do Sul para inoculação em feijoeiro comum

bitstream/item/66207/1/32003.pdfFERTBI

The Imprint of Intermittent Interchange Reconnection on the Solar Wind

The solar wind is known to be highly structured in space and time. Observations from Parker Solar Probe have revealed an abundance of so-called magnetic switchbacks within the near-Sun solar wind. In this Letter, we use a high-resolution, adaptive-mesh, magnetohydrodynamics simulation to explore the disturbances launched into the solar wind by intermittent/bursty interchange reconnection and how they may be related to magnetic switchbacks. We find that repeated ejection of plasmoid flux ropes into the solar wind produces a curtain of propagating and interacting torsional Alfvénic waves. We demonstrate that this curtain forms when plasmoid flux ropes dynamically realign with the radial field as they are ejected from the current layer and that this is a robust effect of the 3D geometry of the interchange reconnection region. Simulated flythroughs of this curtain in the low corona reveal an Alfvénic patch that closely resembles observations of switchback patches, but with relatively small magnetic field deflections. Therefore, we suggest that switchbacks could be the solar wind imprint of intermittent interchange reconnection in the corona, provided an in situ process subsequently amplifies the disturbances to generate the large deflections or reversals of radial field that are typically observed. That is to say, our results indicate that a combination of low-coronal and inner-heliospheric mechanisms may be required to explain switchback observations

Anisolepis longicauda

Anisolepis longicauda is listed as Vulnerable because the extent of occurrence is approximately 7,750 km2, the species occurs in two locations (defined by habitat loss from dam construction), and there is an ongoing decline in the extent and quantity of its habitat as a result of the construction of the Yacireta dam.Fil: Arzamendia, Vanesa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; ArgentinaFil: Fitzgerald, L.. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo; ArgentinaFil: Giraudo, Alejandro Raul. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; ArgentinaFil: Kacoliris, F.. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo; ArgentinaFil: Montero, R.. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo; ArgentinaFil: Pelegrin, Nicolas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales; ArgentinaFil: Scrocchi Manfrini, Gustavo Jose. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo; ArgentinaFil: Williams, J.. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo; Argentin

P2X receptors: epithelial ion channels and regulators of salt and water transport.

When the results from electrophysiological studies of renal epithelial cells are combined with data from in vivo tubule microperfusion experiments and immunohistochemical surveys of the nephron, the accumulated evidence suggests that ATP-gated ion channels, P2X receptors, play a specialized role in the regulation of ion and water movement across the renal tubule and are integral to electrolyte and fluid homeostasis. In this short review, we discuss the concept of P2X receptors as regulators of salt and water salvage pathways, as well as acknowledging their accepted role as ATP-gated ion channels

The Second Transmembrane Domain of P2X7 Contributes to Dilated Pore Formation

Activation of the purinergic receptor P2X7 leads to the cellular permeability of low molecular weight cations. To determine which domains of P2X7 are necessary for this permeability, we exchanged either the C-terminus or portions of the second transmembrane domain (TM2) with those in P2X1 or P2X4. Replacement of the C-terminus of P2X7 with either P2X1 or P2X4 prevented surface expression of the chimeric receptor. Similarly, chimeric P2X7 containing TM2 from P2X1 or P2X4 had reduced surface expression and no permeability to cationic dyes. Exchanging the N-terminal 10 residues or C-terminal 14 residues of the P2X7 TM2 with the corresponding region of P2X1 TM2 partially restored surface expression and limited pore permeability. To further probe TM2 structure, we replaced single residues in P2X7 TM2 with those in P2X1 or P2X4. We identified multiple substitutions that drastically changed pore permeability without altering surface expression. Three substitutions (Q332P, Y336T, and Y343L) individually reduced pore formation as indicated by decreased dye uptake and also reduced membrane blebbing in response to ATP exposure. Three others substitutions, V335T, S342G, and S342A each enhanced dye uptake, membrane blebbing and cell death. Our results demonstrate a critical role for the TM2 domain of P2X7 in receptor function, and provide a structural basis for differences between purinergic receptors. © 2013 Sun et al

Effectiveness of TNF-α blockade in the treatment of refractory non-infectious scleritis: a multicentre study

OBJECTIVES: To evaluate the efficacy of tumour necrosis factor (TNF)-α inhibitors in refractory non-infectious scleritis. METHODS: We carried out a retrospective study assessing the efficacy of TNF-α inhibitors in the treatment of scleritis, scleritis relapses, glucocorticoid (GC)-sparing effect, impact on best-corrected visual acuity (BCVA) and safety profile. RESULTS: Nineteen patients (28 eyes) were eligible for analysis. Scleritis inflammatory grading significantly improved from baseline to the last follow-up (median ± IQR 2±4 and 0±0 respectively, p=0.0006). Scleritis relapses significantly decreased between the 12 months preceding and following biologic therapy (p=0.001). Mean GC dosage decreased from baseline (19.00±13.56 mg) to the last follow-up (7.59±5.56 mg) (p=0.003). No significant differences regarding BCVA were observed. Two AEs were recorded (1 severe urticaria and 1 case of pneumonia and paradoxical psoriasis). CONCLUSIONS: TNF-α inhibitors are effective in the treatment of scleritis while allowing a GC-sparing effect and preserving BCVA