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In situ loading and delivery of short single- And double-stranded dna by supramolecular organic frameworks
Short DNA represents an important class of biomacromolecules that are widely applied in gene therapy, editing, and modulation. However, the development of simple and reliable methods for their intracellular delivery remains a challenge. Herein, we describe that seven water-soluble, homogeneous supramolecular organic frameworks (SOFs) with a well-defined pore size and high stability in water that can accomplish in situ inclusion of single-stranded (ss) and double-stranded (ds) DNA (21, 23, and 58 nt) and effective intracellular delivery (including two noncancerous and six cancerous cell lines). Fluorescence quenching experiments for single and double endlabeled ss- and ds-DNA support that the DNA sequences can be completely enveloped by the SOFs. Confocal laser scanning microscopy and flow cytometry reveal that five of the SOFs exhibit excellent delivery efficiencies that, in most of the studied cases, outperform the commercial standard Lipo2000, even at low SOF-nucleic acid ratios. In addition to high delivery efficiencies, the watersoluble, self-assembled SOF carriers have a variety of advantages, including convenient preparation, high stability, and in situ DNA inclusion, which are all critical for practical applications in nucleic acid delivery
Comparative study of stirrup-confined circular concrete-filled steel tubular stub columns under axial loading
© 2017 Elsevier Ltd This paper presents a comparative study of circular concrete-filled steel tubular stub columns with three different stirrup confinement types: bidirectional stirrups, loop stirrups and orthogonal stirrups. Axial compression tests have been carried out aiming at investigating the effects of the stirrup form and volume-stirrup ratio on the mechanical behavior of the stirrup-confined circular CFT stub columns, and ABAQUS was used to carry out the 3D numerical modelling. Radial stress of the core concrete and the composite action among the steel tube, stirrups and the core concrete have been investigated. It is found that the confinement provided by stirrups on core concrete strongly outperforms that provided by steel tube, steel sections or steel reinforcement. Furthermore, a simplified approach was developed to predict the ultimate bearing capacity of stirrup-confined circular CFT stub columns, which agreed well with the experimental and numerical results
Alternativas en camino en Foz de Iguazú: pensando una educación para los derechos humanos y el territorio
Anais do IV Encontro de Iniciação Científica da Unila - “UNILA 5 anos: Integração em Ciência, Tecnologia e Cultura na Tríplice Fronteira” - 05 e 06 de novembro de 2015 – Sessão Ciência Política, Sociologia, Filosofia e AntropologiaEste artículo se propone realizar un análisis de los impactos que pudó haber generado el
desarrollo del proyecto de extensión “Educación para la Ciudadanía y el Territorio”, durante el
año 2014 en el Colegio Estadual Gustavo Dobradinho, en el barrio de Porto Meira, Foz do
Iguazú. El proyecto fue desarrollado por estudiantes y docentes de la Universidad Federal de la
Integración Latinoamericana en las dos turmas del 3 er año, tanto matutino como nocturno. Para
conseguir detectar impactos del proyecto y analizarlos, objetivos de esta investigación,
utilizaremos como fuente de análisis nuestro diario de campo etnográfico, entrevistas y
cuestionarios realizados a los/as educandos/as, educadores/as y a la directora del Colegio.
También buscaremos demostrar la importancia de trabajar conceptos como el de derechos
humanos, territorio y educación especialmente en escuelas públicas con contexto socio-
económico vulnerable, considerandolo como mecanismo de empoderamiento de los sectores
populares. Entendemos que es a partir de ese tipo de procesos que se puede llegar a una mayor
participación popular en los procesos de decisión política, económica y social que visan la
garantía y efectivación de derechos. Destacamos la importancia del proyecto de extensión al
haber abordado tematicas como participación política, derecho a la ciudad, a la moradia, al
transporte, en un contexto de elecciones nacionales y de proximas remociones habitacionales en
el barrio.
Este trabajo es sudivido en tres partes. En primer lugar encontrarán “Globalización,
neoliberalismo y problemáticas urbanas” dónde se realiza una breve contextualización de los
procesos urbanos desarrollados en Brasil en los últimos años desde la implantación de las
políticas neoliberales dentro de la dinámica nacional – internacional. También se estudia, en esa
primera parte, el barrio y el contexto de la Triple Frontera - donde se desarrolló el proyecto de
extensión “Educación para la Ciudadanía y el territorio” – dentro de dichos procesos urbanos. La
segunda subdivisión, llamada “Prácticas que construyen alternativas: educando para la
participación popular”, es dedicada al estudio de los impactos de la acción de extensión tanto en
la escuela como en el cotidiano de los/as educando que participaron. Por último, a modo de
reflexión acerca de la investigación y sus resultados, están las Consideraciones Finales.
Agradecemos al Conselho Nacional de Pesquisa - CNPQ por la bolsa/beca de iniciación
científica concedida.Bolsista del Programa PROBIC UNILA 2014/2015 / Bolsa financiada por la CNP
High-mass X-ray binaries and OB-runaway stars
High-mass X-ray binaries (HMXBs) represent an important phase in the
evolution of massive binary systems. HMXBs provide unique diagnostics to test
massive-star evolution, to probe the physics of radiation-driven winds, to
study the process of mass accretion, and to measure fundamental parameters of
compact objects. As a consequence of the supernova explosion that produced the
neutron star (or black hole) in these systems, HMXBs have high space velocities
and thus are runaways. Alternatively, OB-runaway stars can be ejected from a
cluster through dynamical interactions. Observations obtained with the
Hipparcos satellite indicate that both scenarios are at work. Only for a
minority of the OB runaways (and HMXBs) a wind bow shock has been detected.
This might be explained by the varying local conditions of the interstellar
medium.Comment: 15 pages, latex (sty file included) with 5 embedded figures (one in
jpg format), to appear in Proc. "Influence of binaries on stellar population
studies", Eds. Vanbeveren, Van Rensberge
Performance of the self-Q-switched Cr,Yb : YAG laser
We report on the spectral properties of Cr, Yb:YAG crystal co-doped with 0.025 at.% Cr and 10 at.% Yb are reported. Using a continuous wave Ti:sapphire laser as a pumping source, we have demonstrated the self-Q-switched Cr,Yb:YAG laser at room temperature. 1 c obtained an average output power as much as 75 mW at 1.03 mum with a pulse width (FWHM) as short as 0.4 mus. The laser experiment demonstrated that the Cr,Yb:YAG crystal exactly combines the Cr4+ saturable absorber and Yb3+ gain medium. The Cr, Yb: YAG crystal can be a most promising self-Q-switched laser crystal for compact and efficient solid-state lasers
Extracts of Feijoa Inhibit Toll-Like Receptor 2 Signaling and Activate Autophagy Implicating a Role in Dietary Control of IBD
Inflammatory bowel disease (IBD) is a heterogeneous chronic inflammatory disease affecting the gut with limited treatment success for its sufferers. This suggests the need for better understanding of the different subtypes of the disease as well as nutritional interventions to compliment current treatments. In this study we assess the ability of a hydrophilic feijoa fraction (F3) to modulate autophagy a process known to regulate inflammation, via TLR2 using IBD cell lines
Subanesthetic ketamine treatment promotes abnormal interactions between neural subsystems and alters the properties of functional brain networks
Acute treatment with subanesthetic ketamine, a non-competitive N-methyl-D-aspartic acid (NMDA) receptor antagonist, is widely utilized as a translational model for schizophrenia. However, how acute NMDA receptor blockade impacts on brain functioning at a systems level, to elicit translationally relevant symptomatology and behavioral deficits, has not yet been determined. Here, for the first time, we apply established and recently validated topological measures from network science to brain imaging data gained from ketamine-treated mice to elucidate how acute NMDA receptor blockade impacts on the properties of functional brain networks. We show that the effects of acute ketamine treatment on the global properties of these networks are divergent from those widely reported in schizophrenia. Where acute NMDA receptor blockade promotes hyperconnectivity in functional brain networks, pronounced dysconnectivity is found in schizophrenia. We also show that acute ketamine treatment increases the connectivity and importance of prefrontal and thalamic brain regions in brain networks, a finding also divergent to alterations seen in schizophrenia. In addition, we characterize how ketamine impacts on bipartite functional interactions between neural subsystems. A key feature includes the enhancement of prefrontal cortex (PFC)-neuromodulatory subsystem connectivity in ketamine-treated animals, a finding consistent with the known effects of ketamine on PFC neurotransmitter levels. Overall, our data suggest that, at a systems level, acute ketamine-induced alterations in brain network connectivity do not parallel those seen in chronic schizophrenia. Hence, the mechanisms through which acute ketamine treatment induces translationally relevant symptomatology may differ from those in chronic schizophrenia. Future effort should therefore be dedicated to resolve the conflicting observations between this putative translational model and schizophrenia
Simvastatin inhibits TLR8 signaling in primary human monocytes and spontaneous TNF production from rheumatoid synovial membrane cultures
Simvastatin has been shown to have anti-inflammatory effects that are independent of its serum cholesterol lowering action, but the mechanisms by which these anti-inflammatory effects are mediated have not been elucidated. To explore the mechanism involved, the effect of simvastatin on Toll-like receptor (TLR) signalling in primary human monocytes was investigated. A short pre-treatment with simvastatin dose-dependently inhibited the production of tumor necrosis factor-α (TNF) in response to TLR8 (but not TLRs 2, 4, or 5) activation. Statins are known inhibitors of the cholesterol biosynthetic pathway, but intriguingly TLR8 inhibition could not be reversed by addition of mevalonate or geranylgeranyl pyrophosphate; downstream products of cholesterol biosynthesis. TLR8 signalling was examined in HEK 293 cells stably expressing TLR8, where simvastatin inhibited IKKα/β phosphorylation and subsequent NF-κB activation without affecting the pathway to AP-1. Since simvastatin has been reported to have anti-inflammatory effects in RA patients and TLR8 signalling contributes to TNF production in human RA synovial tissue in culture, simvastatin was tested in these cultures. Simvastatin significantly inhibited the spontaneous release of TNF in this model which was not reversed by mevalonate. Together, these results demonstrate a hitherto unrecognized mechanism of simvastatin inhibition of TLR8 signalling that may in part explain its beneficial anti-inflammatory effects
Automatic control of finite element models for temperature-controlled radiofrequency ablation
BACKGROUND: The finite element method (FEM) has been used to simulate cardiac and hepatic radiofrequency (RF) ablation. The FEM allows modeling of complex geometries that cannot be solved by analytical methods or finite difference models. In both hepatic and cardiac RF ablation a common control mode is temperature-controlled mode. Commercial FEM packages don't support automating temperature control. Most researchers manually control the applied power by trial and error to keep the tip temperature of the electrodes constant. METHODS: We implemented a PI controller in a control program written in C++. The program checks the tip temperature after each step and controls the applied voltage to keep temperature constant. We created a closed loop system consisting of a FEM model and the software controlling the applied voltage. The control parameters for the controller were optimized using a closed loop system simulation. RESULTS: We present results of a temperature controlled 3-D FEM model of a RITA model 30 electrode. The control software effectively controlled applied voltage in the FEM model to obtain, and keep electrodes at target temperature of 100°C. The closed loop system simulation output closely correlated with the FEM model, and allowed us to optimize control parameters. DISCUSSION: The closed loop control of the FEM model allowed us to implement temperature controlled RF ablation with minimal user input
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