2,016 research outputs found
Dynamical generation of interwoven soliton trains by nonlinear emission in binary Bose-Einstein condensates
We propose a method for the generation of trains of alternating bright
solitons in two-component Bose-Einstein condensates, using controlled emission
of nonlinear matter-waves in the uncoupled regime with spatially-varying
intra-species interaction and out-of-phase oscillations of the ground states in
the trap. Under this scheme, solitons are sequentially launched from the
different components, and interact with each other through phase-independent
cross-coupling. We obtain an analytical estimation of the critical condition
for soliton emission using a geometric guiding model, in analogy with
integrated optical systems. In addition, we show how strong initial
perturbations in the system can trigger the spontaneous generation of
supersolitons, i.e. localized phonon-like excitations of the soliton trains.
Finally, we demonstrate the controllable generation of slow and fast
supersolitons by adding external localized potentials in the nonlinear region
Nanoplastics: From tissue accumulation to cell translocation into Mytilus galloprovincialis hemocytes. resilience of immune cells exposed to nanoplastics and nanoplastics plus Vibrio splendidus combination
Plastic litter is an issue of global concern. In this work Mytilus galloprovincialis was used to study the distribution and effects of polystyrene nanoplastics (PS NPs) of different sizes (50 nm, 100 nm and 1 mu m) on immune cells. Internalization and translocation of NPs to hemolymph were carried out by in vivo experiments, while endocytic routes and effects of PS NPs on hemocytes were studied in vitro. The smallest PS NPs tested were detected in the digestive gland and muscle. A fast and size-dependent translocation of PS NPs to the hemolymph was recorded after 3 h of exposure. The internalization rate of 50 nm PS NPs was lower when caveolae and clathrin endocytosis pathways were inhibited. On the other hand, the internalization of larger particles decreased when phagocytosis was inhibited. The hemocytes exposed to NPs had changes in motility, apoptosis, ROS and phagocytic capacity. However, they showed resilience when were infected with bacteria after PS NP exposure being able to recover their phagocytic capacity although the expression of the antimicrobial peptide Myticin C was reduced. Our findings show for the first time the translocation of PS NPs into hemocytes and how their effects trigger the loss of its functional parameters
Myrosmodes nervosa (Orchidaceae, Cranichidinae, subgenus Myrosmodes): nueva combinación de Myrosmodes para Chile
De acuerdo a datos macromorfológicos y de hábitat se transfiere Altensteinia nervosa Kraenzl. al género Myrosmodes. Se describela especie y se establece el tipo.De acuerdo a datos macromorfológicos y de hábitat se transfiere Altensteinia nervosa Kraenzl. al género Myrosmodes. Se describela especie y se establece el tipo
LEDGF/p75 TATA-less promoter is driven by the transcription factor Sp1.
PSIP1 (PC4 and SFRS1 interacting protein 1) encodes two splice variants: lens epithelium-derived growth factor or p75 (LEDGF/p75) and p52. PSIP1 gene products were shown to be involved in transcriptional regulation, affecting a plethora of cellular processes, including cell proliferation, cell survival, and stress response. Furthermore, LEDGF/p75 has implications for various diseases and infections, including autoimmunity, leukemia, embryo development, psoriasis, and human immunodeficiency virus integration. Here, we reported the first characterization of the PSIP1 promoter. Using 5' RNA ligase-mediated rapid amplification of cDNA ends, we identified novel transcription start sites in different cell types. Using a luciferase reporter system, we identified regulatory elements controlling the expression of LEDGF/p75 and p52. These include (i) minimal promoters (-112/+59 and +609/+781) that drive the basal expression of LEDGF/p75 and of the shorter splice variant p52, respectively; (ii) a sequence (+319/+397) that may control the ratio of LEDGF/p75 expression to p52 expression; and (iii) a strong enhancer (-320/-207) implicated in the modulation of LEDGF/p75 transcriptional activity. Computational, biochemical, and genetic approaches enabled us to identify the transcription factor Sp1 as a key modulator of the PSIP1 promoter, controlling LEDGF/p75 transcription through two binding sites at -72/-64 and -46/-36. Overall, our results provide initial data concerning LEDGF/p75 promoter regulation, giving new insights to further understand its biological function and opening the door for new therapeutic strategies in which LEDGF/p75 is involved
The pitfall-trap of species conservation priority setting
This an accepted author's manuscript (AAM) version of an article published in Biodiversity and Conservation, 20 (2011): 663-68
Characterization of a birnavirus isolated from diseased turbot cultured in Spain
7 pages, 5 figures, 2 tables.During 1989, light but persistent mortalities were detected in a turbot Scophthalmus
maximus L. farm in Galicia (northwestern Spain) and a virus with the characteristics of a birnavirus was
isolated. The purpose of this study was to characterize the viral agent and determine the susceptibility
of turbot to this virus. Electron microscopic examination revealed that the particles were isometric,
hexagonal and unenveloped with an average diameter of 58 to 60 nm. The molecular weights of the
RNA segments were 1.9 and 2.0 x 10(up to 6) daltons. The cells most susceptible to the turbot isolate were the
CHSE-214, FHM and RTG-2 lines and the optimal temperature range for its replication was 15 to 2OºC.
The RNA and polypeptide electropherotypes show that this virus resembles the Ab serotype of infectious
pancreatic necrosis virus (IPNV); however, it differs in that it replicates in the FHM cell line and
is not neutralized by antisera to the classical serotypes of IPNV. Infectivity trials conducted in turbot of
dlfferent sizes indicated that the virus produced mortality only in small fish (2 g), although the larger
fish (30 g) harbored the virus for at least 35 d. Fish inoculated with this isolate showed no pancreatic
necrosis although necrosis of the hematopoietic elements of the kidney and spleen was detected.This work
was supported by Grants MAR 89-0270 from the Comision
Interministenal de Ciencia y Tecnologia (CICYT), and by
XUGA 70708888 from Xunta de Galicia, Spain. Beatriz Novoa
acknowledges the Ministerio de Educacion y Ciencia (Spain)
for a research fellowship.Peer reviewe
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