Apresentação

É com imenso prazer que apresentamos ao público leitor esta edição do periódico científico Polifonia, número 37, revista articulada ao Programa de Pós-Graduação em Estudos da Linguagem da Universidade Federal de Mato Grosso (UFMT). Dada a quantidade de artigos submetidos, apreciados e aprovados, o número 37 precisou ser dividido em dois, 37.1 e 37.2. Dessa forma, o número 37 contém 16 artigos que refletem a fecundidade do campo de estudos linguísticos, abordando áreas como Análise do Discurso, Gêneros Textuais, Sociolinguística, Metáfora, Linguagem e Tecnologia, Formação de Professores, Sintaxe, Crítica Textual. Como a proposta desse volume era recobrir a diversidade linguística, acreditamos que o objetivo foi alcançado

Entrevista

Convidamos a professora Reinildes Dias, Professora Associada da Faculdade de Letras da UFMG, Ph.D. em Tecnologia Educacional, Montreal Concordia University para responder algumas questões sobre as perspectivas da Linguística Aplicada, Letramentos, linguagem e Tecnologia

Apresentação

É com imenso prazer que apresentamos ao público leitor esta edição do periódico científico Polifonia, número 37, revista articulada ao Programa de Pós-Graduação em Estudos da Linguagem da Universidade Federal de Mato Grosso (UFMT). Dada a quantidade de artigos submetidos, apreciados e aprovados, o número 37 precisou ser dividido em dois, 37.1 e 37.2. Dessa forma, o número 37 contém 16 artigos que refletem a fecundidade do campo de estudos linguísticos, abordando áreas como Análise do Discurso, Gêneros Textuais, Sociolinguística, Metáfora, Linguagem e Tecnologia, Formação de Professores, Sintaxe, Crítica Textual. Como a proposta desse volume era recobrir a diversidade linguística, acreditamos que o objetivo foi alcançado

Photocontrolled wettability changes in polymer microchannels doped with photochromic molecules

The authors demonstrate the possibility to control the fluid flow inside microfluidic networks by photoresponsive capillaries. The approach relies on the use of photochromic molecules undergoing reversible changes in their polarity when irradiated with light of specific wavelength, thus varying the wettability of cyclic olefin copolymer microchannels. The realized photoresponsive elements exhibit a decrease up to 20° between the water contact angles of the native and the irradiated surfaces, which could be exploited for enhancing the penetration flow rate of fluids inside microfluidic channels up to 25%. The photocontrollable microfluidic circuitry presents on-off valve behavior, allowing or blocking liquid filling processes on the base of optical control, thus allowing one to manipulate liquid flow within microfluidic networks without mechanical actuation parts

Renal Denervation for Resistant Hypertension in the contemporary era: A Systematic Review and Meta-analysis

Renal denervation (RDN) is a catheter-based ablation procedure designed to treat resistant hypertension (RH). The objective of our study is to determine the effect of RDN on blood pressure and renal function in patients with RH in comparison to medical therapy alone. We performed an extensive literature search for randomized control trials (RCT) reporting office and 24 hr. blood pressure changes and estimated glomerular filtration rate (eGFR) at baseline and 6 months. We calculated a weighted standardized mean difference of blood pressure and renal outcomes between RDN and control groups using random effects models. Our search yielded 608 studies of which we included 15 studies for the final analysis. A total of 857 patients were treated with RDN and 616 patients treated with medical therapy +/- sham procedure. Only 5 studies were double-blinded RCT with sham control. The adjusted standardized mean difference in the change in office based systolic and diastolic pressures (p = 0.18; p = 0.14); 24 hr. systolic and diastolic pressures (p = 0.20; p = 0.18); and eGFR (p = 0.20) from baseline to 6 months is statistically insignificant with significant heterogeneity. Subgroup analysis showed that among sham controlled trials, 24 hr. systolic blood pressure showed a modest but statistically significant benefit favoring renal denervation in patients with RH. Our meta-analysis of 15 RCTs showed no significant benefit of RDN on blood pressure control in patients with resistant hypertension. Subgroup analysis of sham control studies showed a modest benefit in 24 hr. systolic blood pressure at 6 months with RDN.Open access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

Late post-operative paraparesis after rib penetration of the spinal canal in a patient with neurofibromatous scoliosis

Rib displacement into the spinal canal is a rare cause of paraplegia or paraparesis in patients affected by neurofibromatous scoliosis. We describe a case of paraparesis in a 14-year-old child affected by neurofibromatous dystrophic kyphoscoliosis, treated with combined posterior and anterior spinal arthrodesis. Seventeen days after the surgical treatment the patient developed clinical signs and symptoms of paraparesis. A CT scan showed the head of the fifth rib protruding into the spinal canal with cord compression. Rib resection and posterior cord decompression were carried out following complete neurological recovery

Nanoparticle image velocimetry at topologically structured surfaces

Nanoparticle image velocimetry ͑nano-PIV͒, based on total internal reflection fluorescent microscopy, is very useful to investigate fluid flows within ϳ100 nm from a surface; but so far it has only been applied to flow over smooth surfaces. Here we show that it can also be applied to flow over a topologically structured surface, provided that the surface structures can be carefully configured not to disrupt the evanescent-wave illumination. We apply nano-PIV to quantify the flow velocity distribution over a polydimethylsiloxane surface, with a periodic gratinglike structure ͑with 215 nm height and 2 m period͒ fabricated using our customized multilevel lithography method. The measured tracer displacement data are in good agreement with the computed theoretical values. These results demonstrate new possibilities to study the interactions between fluid flow and topologically structured surfaces

Viscoelastic properties of suspended cells measured with shear flow deformation cytometry

Numerous cell functions are accompanied by phenotypic changes in viscoelastic properties, and measuring them can help elucidate higher level cellular functions in health and disease. We present a high-throughput, simple and low-cost microfluidic method for quantitatively measuring the elastic (storage) and viscous (loss) modulus of individual cells. Cells are suspended in a high-viscosity fluid and are pumped with high pressure through a 5.8 cm long and 200 µm wide microfluidic channel. The fluid shear stress induces large, ear ellipsoidal cell deformations. In addition, the flow profile in the channel causes the cells to rotate in a tank-treading manner. From the cell deformation and tank treading frequency, we extract the frequency-dependent viscoelastic cell properties based on a theoretical framework developed by R. Roscoe [1] that describes the deformation of a viscoelastic sphere in a viscous fluid under steady laminar flow. We confirm the accuracy of the method using atomic force microscopy-calibrated polyacrylamide beads and cells. Our measurements demonstrate that suspended cells exhibit power-law, soft glassy rheological behavior that is cell-cycle-dependent and mediated by the physical interplay between the actin filament and intermediate filament networks

Accurate measurement of the standard U-235(n,f) cross section from thermal to 170 keV neutron energy

An accurate measurement of the U-235(n,f) cross section from thermal to 170 keV of neutron energy has recently been performed at n_TOF facility at CERN using Li-6(n,t)He-4 and B-10(n,alpha)Li-7 as references. This measurement has been carried out in order to investigate a possible overestimation of the U-235 fission cross section evaluation provided by most recent libraries between 10 and 30 keV. A custom experimental apparatus based on in-beam silicon detectors has been used, and a Monte Carlo simulation in GEANT4 has been employed to characterize the setup and calculate detectors efficiency. The results evidenced the presence of an overestimation in the interval between 9 and 18 keV and the new data may be used to decrease the uncertainty of U-235(n,f) cross section in the keV region

The role of melatonin in the pathogenesis of adolescent idiopathic scoliosis (AIS)

The cause of adolescent idiopathic scoliosis (AIS) in humans remains obscure and probably multifactorial. At present, there is no proven method or test available to identify children or adolescent at risk of developing AIS or identify which of the affected individuals are at risk of progression. Reported associations are linked in pathogenesis rather than etiologic factors. Melatonin may play a role in the pathogenesis of scoliosis (neuroendocrine hypothesis), but at present, the data available cannot clearly show the role of melatonin in producing scoliosis in humans. The data regarding human melatonin levels are mixed at best, and the melatonin deficiency as a causative factor in the etiology of scoliosis cannot be supported. It will be an important issue of future research to investigate the role of melatonin in human biology, the clinical efficacy, and safety of melatonin under different pathological situations. Research is needed to better define the role of all factors in AIS development