Application of effective theory and Grassmann variables to model compact binaries with spin

Pós-graduação em Física - IFT

Effect of antioxidants during bovine in vitro fertilization procedures on spermatozoa and embryo development

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Públicos e meios de comunicação: a formação necessária para a interatividade

Technological innovations associated with the media made changes in the production, transmission and reception of mediatic messages. Among them, we highlight the convergence of media, and the consequent multimediality and the emergence of new possibilities of interactivity, allowing the audience to become increasingly active. But for that to happen properly, it is necessary to promote actions aimed to critical and creative use of media. Thus, this paper aims to refl ect on the need for literacy initiatives for the formation of publics, aiming what is considered a productive interactivity.

Cognitive, Mood, and Electroencephalographic Effects of Noninvasive Cortical Stimulation With Weak Electrical Currents

Objectives: The use of noninvasive cortical electrical stimulation with weak currents has significantly increased in basic and clinical human studies. Initial, preliminary studies with this technique have shown encouraging results; however, the safety and tolerability of this method of brain stimulation have not been sufficiently explored yet. The purpose of our study was to assess the effects of direct current (DC) and alternating current (AC) stimulation at different intensities in order to measure their effects on cognition, mood, and electroencephalogram. Methods: Eighty-two healthy, right-handed subjects received active and sham stimulation in a randomized order. We conducted 164 ninety-minute sessions of electrical stimulation in 4 different protocols to assess safety of (1) anodal DC of the dorsolateral prefrontal cortex (DLPFC); (2) cathodal DC of the DLPFC; (3) intermittent anodal DC of the DLPFC and; (4) AC on the zygomatic process. We used weak currents of 1 to 2 mA (for DC experiments) or 0.1 to 0.2 mA (for AC experiment). Results: We found no significant changes in electroencephalogram, cognition, mood, and pain between groups and a low prevalence of mild adverse effects (0.11% and 0.08% in the active and sham stimulation groups, respectively), mainly, sleepiness and mild headache that were equally distributed between groups. Conclusions: Here, we show no neurophysiological or behavioral signs that transcranial DC stimulation or AC stimulation with weak currents induce deleterious changes when comparing active and sham groups. This study provides therefore additional information for researchers and ethics committees, adding important results to the safety pool of studies assessing the effects of cortical stimulation using weak electrical currents. Further studies in patients with neuropsychiatric disorders are warranted.

Electroconvulsive Therapy in Brazil After the "Psychiatric Reform" A Public Health Problem-Example From a University Service

Objectives: The Brazilian public health system does not provide electroconvulsive therapy (ECT), which is limited to a few academic services. National mental health policies are against ECT. Our objectives were to analyze critically the public policies toward ECT and present the current situation using statistics from the Institute of Psychiatry of the University of Sao Paulo (IPq-HCFMUSP) and summary data from the other 13 ECT services identified in the country. Methods: Data regarding ECT treatment at the IPq-HCFMUSP were collected from January 2009 to June 2010 (demographical, number of sessions, and diagnoses). All the data were analyzed using SPSS 19, Epic Info 2000, and Excel. Results: During this period, 331 patients were treated at IPq-HCFMUSP: 221 (67%) were from Sao Paulo city, 50 (15.2%) from Sao Paulo's metropolitan area, 39 (11.8%) from Sao Paulo's countryside, and 20 (6.1%) from other states; 7352 ECT treatments were delivered-63.0% (4629) devoted entirely via the public health system (although not funded by the federal government); the main diagnoses were a mood disorder in 86.4% and schizophrenia in 7.3% of the cases. Conclusions: There is an important lack of public assistance for ECT, affecting mainly the poor and severely ill patients. The university services are overcrowded and cannot handle all the referrals. The authors press for changes in the mental health policies.

Nitric Oxide Synthase in Heart and Thoracic Aorta After Liver Ischemia and Reperfusion Injury: An Experimental Study in Rats

Objectives: We tested the effects of liver reperfusion in the immunohistochemical expression of nitric oxide synthase on the thoracic aorta and the heart. Materials and Methods: We randomized 24 male Wistar rats into 3 groups: (1) control; (2) R2 group, with 60 minutes of partial (70%) liver ischemia and 2 hours of global liver reperfusion; (3) and R6 group, with 60 minutes of partial liver ischemia and 6 hours of global liver reperfusion. Results: In the heart, there was little, diffuse immunohistochemical endothelial staining; immunohistochemical inducible nitric oxide synthase staining was expressed in the adventitia layer of intramyocardial vessels in both cases, with a time-dependent but not statistically significant increase. In the thoracic aorta, a time-dependent decrease in endothelial nitric oxide synthase expression in the muscular layer after reperfusion, which was statistically significant in R6 versus the control. Positive immunostaining for inducible nitric oxide synthase was seen in the muscular and endothelial layers, and this varied from moderate in the control group, to light in the endothelium in groups R2 and R6. Conclusions: We observed changes that may be implicated in heart injury and impairment of aortal tone after liver ischemia and reperfusion injury.

Electroconvulsive therapy use in adolescents: a systematic review

Abstract Background Considered as a moment of psychological vulnerability, adolescence is remarkably a risky period for the development of psychopathologies, when the choice of the correct therapeutic approach is crucial for achieving remission. One of the researched therapies in this case is electroconvulsive therapy (ECT). The present study reviews the recent and classical aspects regarding ECT use in adolescents. Methods Systematic review, performed in November 2012, conformed to the PRISMA statement. Results From the 212 retrieved articles, only 39 were included in the final sample. The reviewed studies bring indications of ECT use in adolescents, evaluate the efficiency of this therapy regarding remission, and explore the potential risks and complications of the procedure. Conclusions ECT use in adolescents is considered a highly efficient option for treating several psychiatric disorders, achieving high remission rates, and presenting few and relatively benign adverse effects. Risks can be mitigated by the correct use of the technique and are considered minimal when compared to the efficiency of ECT in treating psychopathologies.

O efeito protetor do bicarbonato de sódio na nefropatia induzida por contraste radiológico em ratos

Contrastes radiológicos iodados – CI são causa de lesão renal aguda – LRA. Avaliar o efeito renoprotetor do bicarbonato de sódio (Bic) sobre a função renal (clearance de creatinina, Jaff é, Clcr-ml/min/100g) e o perfi l oxidativo (excreção de peróxidos, PU e de malondealdeído urinários, FOX-2 e TBARs, nmol/mgCr ) em ratos com CI. Ratos machos adultos Wistar, 250-300g, tratados 1x/dia, por 5 dias, foram divididos nos grupos: Salina (solução salina 0,9%, 3ml/kg/dia, intraperitoneal-i.p.); CI (ioxitalamato de meglumina e sódio, 3ml/kg, i.p); Bic+Salina (Bic 3ml/kg, i.p, 1 hora antes e 1 hora depois da Salina); Bic+CI (Bic 3ml/ kg, i.p, 1 hora antes e 1 hora depois do CI). CI induziu LRA e o Bic confi rmou seu efeito renoprotetor antioxidante (Clcr/TBARs/PU Salina: 0,59±0,03/0,11±0,02/1,29±0,24 vs Bic+Salina 0,58±0,03/0,13±0,02/1,32±0,64 vs CI 0,22±0,02A/0,19±0,02A/4,77±0, 24A vs Bic+CI 0,51±0,04B/0,13±0,3B/1,80± 0,04B, A/B p<0,05). O Bic confi rmou efeito protetor na LRA por CI, podendo ser considerado como possibilidade terapêutica para pacientes submetidos a CI.

Variable rotational line broadening in the Be star Achernar

Aims. The main theoretical problem for the formation of a Keplerian disk around Be stars is how angular momentum is supplied from the star to the disk, even more so since Be stars probably rotate somewhat subcritically. For instance, nonradial pulsation may transport angular momentum to the stellar surface until (part of) this excess supports the disk-formation/replenishment. The nearby Be star Achernar is presently building a new disk and o ers an excellent opportunity to observe this process from relatively close-up. Methods. Spectra from various sources and epochs are scrutinized to identify the salient stellar parameters characterizing the disk life cycle as defined by H emission. The variable strength of the non-radial pulsation is confirmed, but does not a ect the other results. Results. For the first time it is demonstrated that the photospheric line width does vary in a Be star, by as much as v sin i . 35 km However, unlike assumptions in which a photospheric spin-up accumulates during the diskless phase and then is released into the disk as it is fed, the apparent photospheric spin-up is positively correlated with the appearance of H line emission. The photospheric line widths and circumstellar emission increase together, and the apparent stellar rotation declines to the value at quiescence after the H line emission becomes undetectable

Photocatalytic degradation of phenolic compounds with new TiO2 catalysts

[EN] New TiO2 catalysts have been synthesised by means of a sol–gel method in which aggregates have been selected before thermal treatment. Sieving and calcination temperature have been proved to be key factors in obtaining catalysts with greater photoactivity than that of Degussa P-25. These new catalysts have been characterized by means of transmission electron microscopy (TEM), BET surface area, diffuse reflectance spectroscopy (DRS), UV–vis spectroscopy, Fourier transformed infrared (FTIR) and X-ray diffraction (XRD). The different parameters studied were compared to those obtained from two commercial catalysts (Degussa P-25 and Hombikat-UV100). The photocatalytic efficiency of the new catalysts was evaluated by the degradation of various phenolic compounds using UV light (maximum around 365 nm, 9mW). The catalyst sieved and calcinated at 1023 K, ECT-1023t, showed phenol degradation rates 2.7 times higher than those of Degussa P-25. Also in the degradation of different phenolic compounds, this catalyst showed a higher activity than that of the commercial one. The high photoactivity of this new catalyst has been attributed to the different distribution of surface defects (determined from FTIR studies) and its increased capacity to yield H2O2

Tail bridging vs. patchiness

The subject of this thesis are the interactions between nucleosome core particles (NCPs). NCPs are the primary storage units of DNA in eucaryotic cells. Each NCP consists of a core of eight histone proteins and a strand of DNA, which is wrapped around about two times. Each histone protein has a terminal tail passing over and between the superhelix of the wrapped DNA. Special emphasis was placed on the role of the histone tails, since experimental ndings suggest that the tails have a great in uence on the mutual attraction of the NCPs. In those experiments Mangenot et al. observe a dramatic change in the con guration of the tails, which is accompanied by evidence of mutual attraction between NCPs, when a certain salt concentration is reached. Existing models used in the theoretical approaches and in simulations focus on the description of the histone core and the wrapped DNA, but neglect the histone tails. We introduce the multi chain complex as a new simulation model. Here the histone core and the wrapping DNA are modelled via a charged sphere, while the histone tails are represented by oppositely charged chains grafted on the sphere surface. We start by investigating the parameter space describing a single NCP. The Debye-Huckel potential is used to model the electrostatic interactions and to determine the e ective charge of the NCP core. This value is subsequently used for a study of the pairinteraction of two NCPs via an extensive Molecular Dynamics study. The monomer distribution of the full chain model is investigated. The existence of tail bridges between the cores is demonstrated. Finally, by discriminating between bridging and non-bridging con gurations, we can show that the effect of tail bridging between the spheres does indeed account for the observed attraction. The full chain model can serve as a model to study the acetylation of the histone tails of the nucleosome. The reduction of the charge fraction of the tails, that corresponds to the process of acetylation, leads to a reduction or even the disappearance of the attraction. A recent MC study links this e ect to the unfolding of the chromatin ber in the case of acetylated histone tails. In this case the acetylation of the histone tails leads to the formation of heterochromatin, and one could understand how larger regions of the genetic information could be inactivated through this mechanism.

Mechanical properties and structure of gel systems

Understanding the origins of the mechanical properties and its correlation withrnthe microstructure of gel systems is of great scientific and industrial interest. Inrngeneral, colloidal gels can be classified into chemical and physical gels, accordingrnto the life time of the network bonds. The characteristic di↵erences in gelationrndynamics can be observed with rheological measurements.rnAs a model system, a mixture of sodium silicate and low concentration sulfuric acidrnwas used. Nano-sized silica particles grow and aggregate to a system-spanning gelrnnetwork. The influence of the finite solubility of silica at high pH on the gelationrnwas studied with classical and piezo rheometer. The storage modulus of therngel grew logarithmically with time with two distinct growth laws. A relaxationrnat low frequency was observed in the frequency dependent measurements. I attributernthese two behaviors as a sign of structural rearrangements due to the finiternsolubility of silica at high pH. The reaction equilibrium between formation andrndissolution of bonds leads to a finite life time of the bonds and behavior similar tornphysical gel. The frequency dependence was more pronounced for lower water concentrations,rnhigher temperatures and shorter reaction times. With two relaxationrnmodels, I deduced characteristic relaxation times from the experimental data. Besidesrnrheology, the evolution of silica gels at high pH on di↵erent length scales wasrnstudied by NMR and dynamic light scattering. The results revealed that the primaryrnparticles existed already in sodium silicate and aggregated after the mixingrnof reactants due to a chemical reaction. Throughout the aggregation process thernsystem was in its chemical reaction equilibrium. Applying large oscillatory shearrnstrain to the gel allowed for modifying the gel modulus. The e↵ect of shear andrnshear history on the rheological properties of the gel were investigated. The storagernmodulus of the final gel increased with increasing strain. This behavior can be explained with (i) shear-induced aggregate compaction and (ii) combination ofrnbreakage and new formation of bonds.rnIn comparison with the physical gel-like behavior of the silica gel at high pH, typicalrnchemical gel features were exhibited by other gels formed from various chemicalrnreactions. Influences of the chemical structure modification on the gelation wererninvestigated with the piezo-rheometer. The external stimuli can be applied to tunernthe mechanical properties of the gel systems.

Western Hindus and 'Global Hinduism' - Discourses on Conversion to 'Hindu-Religions', Acceptance of Converts and Social Engagement

The paper deals with the problem of (the often supposedly impossible) conversion to “Hinduism”. I start with an outline of what I call the ‘no conversion possible’ paradigm, and briefl y point to the lack of refl ection on acceptance of converts in most theories of religious conversion. Then, two examples are presented: Firstly, I consider conversion to ISKCON and the discourse on the Hare Krishna movement’s Hinduness. Secondly, I give a brief outline of the globalsanatana dharmamovement as inaugurated by Satguru Siva Subramuniyaswami, a converted American Hindu based in Hawai’i. In the conclusion, I refl ect on (civic) social capital and engagement in global networks as a means to gain acceptance as converts to Hinduism. I argue in line with Stepick, Rey and Mahler (2009) that the religious movements’ civic engagement (in these cases engagement in favour of the Indian diasporic communities and of Hindus in India) provides a means for the individual, non-Indian converts to acquire the social capital that is necessary for gaining acceptance as ‘Hindus’ in certain contexts.