Entity

Time filter

Source Type

Manaus, Brazil

Gurgel W.P.,Federal University of Para | Gurgel W.P.,Institute Criminalistica | Gomes L.M.,Federal University of Para | Ferreira F.C.L.,Federal University of Para | Gester R.M.,Federal University of Para
Revista Brasileira de Ensino de Fisica | Year: 2015

In this paper we present and evaluate the Speed Calculations software for Traffic Accidents (SCTA). This application is designed for forensic studies and follows a protocol that allows the expert in crime scene analysis, even one that has no knowledge of physics, to estimate vehicle speeds involved in collisions and pedestrian accidents. SCTA uses basicconcepts of classical mechanics, employs different coefficients of friction and takes into account the damage and the characteristics of the vehicles involved. This allows to determine the speeds in various accident situations. The softwarefollows an open source philosophy, allowing implementation of new accident scenarios. Finally, as input data, SCTA needsonly a few measurements performed by an expert. This avoids unnecessary scene observation and, optimizes and ensures reliability of forensic expertise. © 2015. Sociedade Brasileira de Física.


Kimura L.,University of Sao Paulo | Ribeiro-Rodrigues E.M.,Federal University of Para | Ribeiro-Rodrigues E.M.,Institute Criminalistica | De Mello Auricchio M.T.B.,University of Sao Paulo | And 3 more authors.
American Journal of Human Biology | Year: 2013

Objectives: xMany Africans were brought to Brazil as slaves. The runaway or abandoned slaves founded isolated communities named quilombos. There are many quilombo remnants in Vale do Ribeira region in the southern part of São Paulo State. The aim of our study was to contribute to understanding the origins of these populations, through admixture studies. Methods: We genotyped 307 unrelated DNA samples obtained from ten quilombo populations from Vale do Ribeira region, using a panel of 48 INDEL polymorphisms. We estimated genetic differentiation between populations (FST) and genomic ancestry from these populations. Our data were compared to a similar study performed in quilombo remnants from the Brazilian Amazon region. Results: Population admixture estimates showed high degree of miscegenation in the quilombo remnants from Vale do Ribeira (average admixture estimates at 39.7% of African, 39.0% of European and 21.3% of Amerindian contribution). The proportions of ancestral genes varied greatly among individuals, ranging from 7.3 to 69.5%, 12.9 to 68.3%, and 7.3 to 58.5% (African, European, and Amerindian, respectively). Genetic differentiation between these populations was low (all FST values <5%), indicating gene flow between them. Both groups of quilombos, from Vale do Ribeira and Amazon, presented similar patterns of admixture. Conclusions: INDEL markers were useful to evidence the triple interbreeding among African, European, and Amerindian in the formation of quilombo populations. The low FST values suggested gene flow among quilombos from Vale do Ribeira. Our data highlight the important role of Amerindians in the formation of quilombo populations. © 2012 Wiley Periodicals, Inc.


Floriani G.,Federal University of Parana | Floriani G.,Institute Criminalistica | Gasparetto J.C.,Federal University of Parana | Pontarolo R.,Federal University of Parana | Goncalves A.G.,Federal University of Parana
Forensic Science International | Year: 2014

Here, an HPLC-DAD method was developed and validated for simultaneous determination of cocaine, two cocaine degradation products (benzoylecgonine and benzoic acid), and the main adulterants found in products based on cocaine (caffeine, lidocaine, phenacetin, benzocaine and diltiazem). The new method was developed and validated using an XBridge C18 4.6. mm. ×. 250. mm, 5. μm particle size column maintained at 60. °C. The mobile phase consisted of a gradient of acetonitrile and ammonium formate 0.05. M - pH 3.1, eluted at 1.0. mL/min. The volume of injection was 10. μL and the DAD detector was set at 274. nm. Method validation assays demonstrated suitable sensitivity, selectivity, linearity, precision and accuracy. For selectivity assay, a MS detection system could be directly adapted to the method without the need of any change in the chromatographic conditions. The robustness study indicated that the flow rate, temperature and pH of the mobile phase are critical parameters and should not be changed considering the conditions herein determined. The new method was then successfully applied for determining cocaine, benzoylecgonine, benzoic acid, caffeine, lidocaine, phenacetin, benzocaine and diltiazem in 115 samples, seized in Brazil (2007-2012), which consisted of cocaine paste, cocaine base and salt cocaine samples. This study revealed cocaine contents that ranged from undetectable to 97.2%, with 97 samples presenting at least one of the degradation products or adulterants here evaluated. All of the studied degradation products and adulterants were observed among the seized samples, justifying the application of the method, which can be used as a screening and quantification tool in forensic analysis. © 2013 Elsevier Ireland Ltd.


Alves H.B.,Institute Criminalistica | Alves H.B.,Pontifical Catholic University of Parana | Leite F.P.N.,Instituto Geral Of Pericias | Sotomaior V.S.,Pontifical Catholic University of Parana | And 4 more authors.
International Journal of Legal Medicine | Year: 2014

Allelic frequencies for 15 STR autosomal loci, using AmpFℓSTR® Identifiler™, forensic, and statistical parameters were calculated. All loci reached the Hardy-Weinberg equilibrium. The combined power of discrimination and mean power of exclusion were 0.999999999999999999 and 0.9999993, respectively. The MDS plot and NJ tree analysis, generated by FST matrix, corroborated the notion of the origins of the Paraná population as mainly European-derived. The combination of these 15 STR loci represents a powerful strategy for individual identification and parentage analyses for the Paraná population. © 2013 Springer-Verlag Berlin Heidelberg.


Verde E.L.,Federal University of Goais | Verde E.L.,Federal University of Mato Grosso | Landi G.T.,University of Sao Paulo | Carriao M.S.,Federal University of Goais | And 5 more authors.
AIP Advances | Year: 2012

Further advances in magnetic hyperthermia might be limited by biological constraints, such as using sufficiently low frequencies and low field amplitudes to inhibit harmful eddy currents inside the patient's body. These incite the need to optimize the heating efficiency of the nanoparticles, referred to as the specific absorption rate (SAR). Among the several properties currently under research, one of particular importance is the transition from the linear to the non-linear regime that takes place as the field amplitude is increased, an aspect where the magnetic anisotropy is expected to play a fundamental role. In this paper we investigate the heating properties of cobalt ferrite and maghemite nanoparticles under the influence of a 500 kHz sinusoidal magnetic field with varying amplitude, up to 134 Oe. The particles were characterized by TEM, XRD, FMR and VSM, from which most relevant morphological, structural and magnetic properties were inferred. Both materials have similar size distributions and saturation magnetization, but strikingly different magnetic anisotropies. From magnetic hyperthermia experiments we found that, while at low fields maghemite is the best nanomaterial for hyperthermia applications, above a critical field, close to the transition from the linear to the non-linear regime, cobalt ferrite becomes more efficient. The results were also analyzed with respect to the energy conversion efficiency and compared with dynamic hysteresis simulations. Additional analysis with nickel, zinc and copper-ferrite nanoparticles of similar sizes confirmed the importance of themagnetic anisotropy and the damping factor. Further, the analysis of the characterization parameters suggested core-shell nanostructures, probably due to a surface passivation process during the nanoparticle synthesis. Finally, we discussed the effect of particle-particle interactions and its consequences, in particular regarding discrepancies between estimated parameters and expected theoretical predictions. Copyright 2012 Author(s).

Discover hidden collaborations