Fragmentation Experiment and Model for Falling Mercury Drops

The experiment consists of counting and measuring the size of the many fragments observed after the fall of a mercury drop on the floor. The size distribution follows a power-law for large enough fragments. We address the question of a possible crossover to a second, different power-law for small enough fragments. Two series of experiments were performed. The first uses a traditional film photographic camera, and the picture is later treated on a computer in order to count the fragments and classify them according to their sizes. The second uses a modern digital camera. The first approach has the advantage of a better resolution for small fragment sizes. The second, although with a poorer size resolution, is more reliable concerning the counting of all fragments up to its resolution limit. Both together clearly indicate the real existence of the quoted crossover. The model treats the system microscopically during the tiny time interval when the initial drop collides with the floor. The drop is modelled by a connected cluster of Ising spins pointing up (mercury) surrounded by Ising spins pointing down (air). The Ising coupling which tends to keep the spins segregated represents the surface tension. Initially the cluster carries an extra energy equally shared among all its spins, corresponding to the coherent kinetic energy due to the fall. Each spin which touches the floor loses its extra energy transformed into a thermal, incoherent energy represented by a temperature used then to follow the dynamics through Monte Carlo simulations. Whenever a small piece becomes disconnected from the big cluster, it is considered a fragment, and counted. The results also indicate the existence of the quoted crossover in the fragment-size distribution.Comment: 6 pages, 3 figure

[Cervix uteri lesions and human papiloma virus infection (HPV): detection and characterization of DNA/HPV using PCR (polymerase chain reaction)]

Tit. em Português: Lesões do Colo Uterino e Infecção pelo Vírus do Papiloma Humano (HPV) Detecção e tipificação do ADN/HPV por PCR (Reacção de amplificação enzimática)The prevalence of human papillomavirus (HPV) genotypes was estimated by the polymerase chain reaction (PCR), in archival paraffin was embedded tissues. The case group consisted of 84 women aged 21-67 years (mean, 40 years) who were referred to the Department of Gynaecology (Oncology Centre, Coimbra) with citopathologically abnormal smears. This group was selected from a population of women who had undergone a screening programme (1990/94) in Central Region of Portugal. All these patients (n = 84) had a colposcopic directed cervical biopsy. HPV detection and typing was performed by the PCR method in the Department of Virology (National Health Care Institute, Lisbon). The prevalence of DNA/HPV found, concerning all epithelial cervical lesions studied and classified as squamous intra-epithelial lesions (SIL) and cervical cancer was 97.8%. On the basis of the data presented in this study, it was estimated that there was a statistically significant prevalence of low risk HPV types (HPV 6/11) in low grade SIL, 83.3%, and a statistically significant prevalence of high risk HPV types (HPV 16,18,31,33,51) in high grade SIL, 58.4%, as well as cervical cancer lesions in 100%. We conclude that there was a statistically significant difference between women with low and high grade SIL for HPV infection, with low and high risk HPV types, respectively. The risk factors for cervical cancer investigated (age at first sexual intercourse, multiple sexual partners, parity, use of oral contraceptives) were not associated to statistically significant differences concerning low grade SIL and high grade SIL. The clinical and therapeutic procedures were evaluated for the same five years (1990/94). It may be concluded that there would be no significant difference in clinical procedure for high grade lesions and cervical cancer, in which the treatment had been frequently radical (cone biopsies, simple or radical hysterectomy) and in which the HPV infection persisted frequently and was associated to high risk types (HPV 16 in 50% of these cases). On the other hand, it may be concluded that HPV detection in cervical biopsies, especially for low grade SIL lesions, which were evaluated in this study with a more conservative procedure (clinical evaluation only, punch biopsies, loop diathermy, CO2 laser vaporisation, cone biopsies), could identify women with high risk HPV types who might be at risk of developing dysplasia and cervical cancer

Non-Avian Reptiles of the state of Rio de Janeiro, Brazil: status of knowledge and commented list

We assessed the current knowledge on non-avian reptile species composition in the state of Rio de Janeiro (RJ), southeastern Brazil. We used published data in indexed journals and verified voucher specimens housed in two herpetological collections of the Museu Nacional (UFRJ), and the Laboratory of Reptiles (ZUFRJ). We also confirmed vouchers from Instituto Vital Brazil (IVB) and from the Museum of Comparative Zoology (MCZ). We compiled a list containing 149 species of reptiles, distributed among Testudines (N = 15), Crocodylia (N = 1) and Squamata (N = 133; six amphisbaenians, 38 lizards and 89 snakes). Our results add 20 species to the previous list known for the state. Four species recorded are endemic to the state of Rio de Janeiro (Anolis neglectus, Glaucomastix littoralis, Leposternon scutigerum, and Liolaemus lutzae). We identified that 21 reptile species recorded in RJ state (nearly 15% of the total) are included in some threat category either in the IUCN, Brazilian (ICMBio) or state lists of endangered species. We also report that seven of the reptiles recorded are non-indigenous to the state: Cnemidophorus aff. lemniscatus (= Cnemidophorus cryptus), Anolis sagrei, Trachemys scripta, Trachemys dorbigni, Hemidactylus mabouia, Crotalus durissus terrificus, and Rhinoclemmys punctularia. The checklist presented here provides a comprehensive database for further research on the herpetofauna of the Brazilian Atlantic Forest

Efeito de concentrações de macronutrientes N, P e K No aumento do espessamento da parede dos traqueídos Pinnus Elliottii (plantas em vasos)

In this paper the authors present the results of the effect of the macronutrients nitrogen, phosphorus and potassium in the increase of fiber length and the thickness of the cell wall in Pinnus elliottii. The statistical analyses shows that higher levels of N seemed to decrease both length of fiber elements and the thickness of the wall. The effect of P and K were not well defined.Neste trabalho os autores apresentam os resultados dos efeitos dos níveis de N, P e K no aumento do comprimento e da espessura da parede dos traqueídos de Pinnus elliottii. A análise estatística mostra que alto nível de N parece indicar uma diminuição no comprimento e na espessura dos traqueídos, enquanto que os efeitos do P e K não se mostram bem definidos, provàvelmente por se tratar de material muito jovem, com apenas dois anos de idade, sob efeito dos tratamentos

Mitochondrial Oxidative Stress and Calcium-Dependent Permeability Transition are Key Players in the Mechanisms of Statins-Associated Side Effects

Statins are cholesterol-lowering medicines utilized worldwide and are associated with reduced risk of cardiovascular mortality and events. However, 0.5–10% of patients suffer from adverse effects especially on skeletal muscle. Recently, new onset of diabetes has been reported in subjects on statin therapy. Pro- and anti-oxidant effects of statins have been reported, thus fostering a debate. Previously reported data provide evidence that statins induce alterations in intracellular calcium homeostasis and mitochondrial dysfunctions that can be counteracted by antioxidants (e.g., CoQ10, creatine, and L-carnitine). Therefore, we have proposed that statin-induced inhibition of mitochondrial respiration leads to oxidative stress that opens a calcium-dependent permeability transition pore, an event that may lead to cell death. In addition, mitochondrial oxidative stress caused by statin treatment may be a signal for cellular antioxidant system responses such as catalase upregulation, possibly explaining the alleged statins’ antioxidant properties. Muscle mitochondrial dysfunction induced by statin treatment may be associated with the peripheral insulin resistance and may explain statins-induced new onset of diabetes. Together, the data presented in this review suggest that the statins’ detrimental effects can be prevented by co-administration of antioxidants

LZS/Al2O3 nanostructured composites obtained by colloidal processing and spark plasma sintering

[EN] Li2O-SiO2-ZrO2 (LZS) glass-ceramics have high mechanical strength, hardness, resistance to abrasion and chemical attack, but also a high coefficient of thermal expansion (CTE), which can be reduced adding alumina nanoparticles. The conventional glass-ceramic production is relatively complex and energy consuming, since it requires the melting of the raw materials to form a glass frit and a two-step milling process to obtain particle sizes adequate for compaction. This study describes the preparation of LZS glass-ceramics through a colloidal processing approach from mixtures of SiO2 and ZrO2 nanopowders and a Li precursor (lithium acetate obtained by reaction of the carbonate with acetic acid). Concentrated suspensions were freeze-dried to obtain homogeneous mixtures of powders that were pressed (100 MPa) and sintered conventionally and by spark plasma sintering. The effect of the alumina nanoparticles additions on suspensions rheology, sintering behavior and properties such as thermal expansion, thermal conductivity, hardness and Young's modulus were evaluated. (C) 2017 Elsevier Ltd. All rights reserved.This work has been supported by Ministerio de Economia y Competitividad (MINECO) and FEDER Funds under grant No MAT2016-67586-C3-R. Authors greatly acknowledge the financial Support of CAPES in the frame of the International Cooperation Program Science without Borders for Special Visiting Researcher PVE (MEC/MCTI/CAPES/CNPQ/FAPs/No 71/2013), Project no. A011/2013. A. Borrell acknowledges the MINECO for her Juan de la Cierva-Incorporacion contract (IJCI-2014-19839).Arcaro, S.; Novaes De Oliveira, A.; Gutierrez-Gonzalez, C.; Salvador Moya, MD.; Borrell Tomás, MA.; Moreno, R. (2017). LZS/Al2O3 nanostructured composites obtained by colloidal processing and spark plasma sintering. Journal of the European Ceramic Society. 37(16):5139-5148. https://doi.org/10.1016/j.jeurceramsoc.2017.03.023S51395148371

ERP correlates of error processing during performance on the HalsteadCategory Test

The Halstead Category Test (HCT) is a neuropsychological test that measures a person's ability to formulate and apply abstract principles. Performance must be adjusted based on feedback after each trial and errors are common until the underlying rules are discovered. Event-related potential (ERP) studies associated with the HCT are lacking. This paper demonstrates the use of amethodology inspired on Singular SpectrumAnalysis (SSA) applied to EEG signals, to remove high amplitude ocular andmovement artifacts during performance on the test. This filtering technique introduces no phase or latency distortions, with minimum loss of relevant EEG information. Importantly, the test was applied in its original clinical format, without introducing adaptations to ERP recordings. After signal treatment, the feedback-related negativity (FRN) wave, which is related to error-processing, was identified. This component peaked around 250ms, after feedback, in fronto-central electrodes. As expected, errors elicited more negative amplitudes than correct responses. Results are discussed in terms of the increased clinical potential that coupling ERP informationwith behavioral performance data can bring to the specificity of theHCT in diagnosing different types of impairment in frontal brain function.info:eu-repo/semantics/publishedVersio

Cinco anos do PPGED-UEPA na Amazônia: trajetórias, avanços e possibilidades acadêmicas

Este artigo socializa a trajetória vivenciada pelo"Programa de Pós-Graduação em educação-Mestrado, do Centro de Ciências Sociais e Educação (CCSE), da Universidade do Estado do Pará"(UEPA), em seus cinco anos de existência. Apresenta os avanços e dificuldades apresentadas no"percurso de consolidação de seu projeto acadêmico, com base em levantamento bibliográfico e"documental. Com setenta dissertações defendidas"em duas linhas de pesquisa o PPGED tem contribuído para fortalecer a produção educacional em"contextos amazônicos. Mesmo com os avanços"significativos visualizados tanto na infraestrutura"como nos encaminhamentos didático-científicos,"o Programa sente falta de políticas institucionais"que garantam sua autonomia de gestão, o que inclui a destinação de orçamento necessário para"manter as suas ações. Neste aspecto, há necessidade de se manter diálogo permanente entre"o PPGED e as instâncias a que o programa está"vinculado, de modo a garantir condições para"produção do conhecimento e assim fortalecer o"campo educacional, especialmente na Amazônia Paraense."Palavras-chave: Educação. Programa de Pós- graduação. UEPA. Amazônia."Five years of "PPGED -UEPA in the Amazon: routes, trajectories, improvements and academic possibilities"This article socializes the trajectory experienced by the Post-graduate Program in Education (PPGED)Master’s Degree of Centro de Ciências Sociais e Educação (CCSE), of Universidade do Estado do Pará (UEPA), along its five years of existence. It presents improvements and difficulties emerged throughout the consolidation of its academic project, based on bibliographic and documental research. The PPGED has registered seventy seven developed dissertations in its two research areas and has contributed to strengthen the educational production within Amazonian contexts. Despite the relevant and evident progress achieved both in infrastructure and in scientific and didactic processes, the Program still lacks institutional policies that guarantee its management autonomy, which includes the destination of the necessary budget in order to maintain its actions. Concerning this, it is necessary to maintain permanent dialogue between PPGED and the other instances to which the program is linked, aiming at developing conditions for the production of knowledge and thus strengthening the educational field, especially in the Amazon of Para.Keywords: Education. Post Graduate Program. UEPA. Amazon." ""

A quantum-like description of the planetary systems

The Titius-Bode law for planetary distances is reviewed. A model describing the basic features of this rule in the "quantum-like" language of a wave equation is proposed. Some considerations about the 't Hooft idea on the quantum behaviour of deterministic systems with dissipation are discussed.Comment: LaTex file, 17 pages, no figures. Version published in Foundations of Physics, August 200