2,456 research outputs found
Computational thinking and robotics in education
After the computational thinking sessions in the previous 2016-2018 editions of TEEM Conference, the fourth edition of this track has been organized in the current 2019 edition. Computational thinking is still a very significant topic, especially, but not only, in pre-university education. In this edition, the robotic has a special role in the track, with a strength relationship with the STEM and
STEAM education of children at the pre-university levels, seeding the future of our society
Increment at molt for the Norway lobster (Nephrops norvegicus) from the south coast of Portugal
The increment at molt for Nephrops norvegicus was studied with the objective of obtaining a model for prediction of post-molt size based on pre-molt size for the population from the south coast of Portugal. Wild animals were maintained in a specially prepared laboratory facility until they malted. Individual values of increment at molt were obtained and used to evaluate alternative models and estimate their parameters. Six alternative models, used previously by several authors to relate pre- and post-molt size, were modified so that increment at molt was the dependent variable and pre-molt size the independent variable. These included the linear relationship of the growth factor (GF) on pre-molt size, the Hiatt equation, post-molt size a power function of pre-molt size, the hyperbolic function, GF exponential function of pre-molt size and the Misra equation. The analysis of the data showed that none of the models could be used to predict increment at molt for either sex. The distribution of the increment at molt was a random normal variable, with mean values not significantly different between sexes, 2.78 mm for males and 2.26 mm for females, variances 0.47 and 0.59, respectively. An analysis of the models suggests that using post-molt size or the GF as dependent variables may lead to a misinterpretation of the dependency of these variables on pre-molt size. It is suggested that the increment at molt should be the variable of interest for predicting post-molt size. The choice of a mathematical formulation should, besides having biological meaning, have the capacity of expressing a true relationship between increment at molt and pre-molt carapace length, namely, be able to model several options for the increment at molt after maturity, including a steady increase of the increment through life, the stabilization of the increment after maturity or the decrease of the increment for larger sizes. (C) 2003 International Council for the Exploration of the Sea. Published by Elsevier Ltd. All rights reserved.info:eu-repo/semantics/publishedVersio
Gold nanoparticles as a part of a photothermal therapy system.
Introduction
Photothermal therapy (PTT) is attracting increased attention for the treatment of superficial localized
tumors, relying on the induction of local hyperthermia of tumor cells upon their irradiation with light
beams1. PTT efficacy depends, however, on the heat generated and, on the depth reached by the light.
Some strategies to improve PTT efficacy includes the use of the near infrared (NIR, 650 to 900 nm)
radiation to enhance the penetration depth of the light, combined with gold nanoparticles (AuNPs) to
enhance the photothermal effect2.
Experimental Methods
Core AuNPs were synthesized by a novel method using tetrachloroauric acid and a mixture of reducing
agents, and subsequently coated with a combination of hyaluronic and oleic acids, for improving the NPs
biocompatibility, biodegradability, and lifetime. This coating also promotes the binding of specific cell
receptors of the tumor cells. The particles were physico-chemically characterized, and in vitro and in vivo
tests were carried out in breast cancer models to assess their safety and efficacy, when applied alone or
combined with NIR irradiation3.
Results and Discussion
AuNPs presented a predominant spherical morphology with sizes under 350 nm, polydispersity index lower
than 0.4 and enhanced absorbance in the NIR. The particles showed no toxicity in vitro and promising
efficacy in vivo when administering the NPs in situ and later irradiating them externally. Histopathological
analysis of tumors treated with both AuNPs and laser irradiation showed the presence of necrosis in most
of the tumors and no effect or practically absence in healthy surrounding cells, which are very encouraging
outcomes.
Conclusion
The results are promising, however, there is still room for improving the system, namely by reducing even
more the invasiveness of the treatment through the combined use of aerogels structures. Aerogel’s unique
properties4 make them ideal candidates to minimize the exposure of healthy tissues to laser radiation,
acting as light and thermal insulators, as well as to incorporate the nanoparticles into their skeletal
structure and thus potentiating a topical application of the particles. For these reasons, some exploratory
methods were carried to produce and design aerogels structures for PTT applications
Parasites of the reintroduced Iberian Lynx (Lynx pardinus) and Sympatric Mesocarnivores in Extremadura, Spain
Research Areas: MicrobiologyABSTRACT - The Iberian lynx (Lynx pardinus) is one of the most endangered felid species in the world.
Conservation efforts have increased its population size and distribution and reinforced their genetic
diversity through captive breeding and reintroduction programmes. Among several threats that the
Iberian lynx faces, infectious and parasitic diseases have underlined effects on the health of their
newly reintroduced populations, being essential to identify the primary sources of these agents
and assess populations health status. To achieve this, 79 fresh faecal samples from Iberian lynx
and sympatric mesocarnivores were collected in the reintroduction area of Extremadura, Spain.
Samples were submitted to copromicroscopic analyses to assess parasite diversity, prevalence, and
mean intensity of parasite burden. Overall, 19 (24.1%, ±15.1–35.0) samples were positive for at
least one enteric parasite species. Parasite diversity and prevalence were higher in the Iberian lynx
(43.8%) compared with the others mesocarnivores under study (e.g., the red fox Vulpes vulpes and
the Egyptian mongoose Herpestes ichneumon). Ancylostomatidae and Toxocara cati were the most
prevalent (15.6%) parasites. Obtained results revealed that Iberian lynx role as predator control
might have reduced parasite cross-transmission between this felid and mesocarnivores due to their
decreasing abundances. Surveillance programs must include regular monitoring of this endangered
felid, comprising mesocarnivores, but also domestic/feral and wild cat communities.info:eu-repo/semantics/publishedVersio
Compilation of parameterized seismogenic sources in Iberia for the SHARE European-scale seismic source model.
Abstract: SHARE (Seismic Hazard Harmonization in Europe) is an EC-funded project (FP7) that aims to evaluate European seismic hazards using an integrated, standardized approach. In the context of SHARE, we are compiling a fully-parameterized active fault database for Iberia and the nearby offshore region. The principal goal of this initiative is for fault sources in the Iberian region to be represented in SHARE and incorporated into the source model that will be used to produce seismic hazard maps at the European scale. The SHARE project relies heavily on input from many regional experts throughout the Euro-Mediterranean region. At the SHARE regional meeting for Iberia, the 2010 Working Group on Iberian Seismogenic Sources (WGISS) was established; these researchers are contributing to this large effort by providing their data to the Iberian regional integrators in a standardized format. The development of the SHARE Iberian active fault database is occurring in parallel with IBERFAULT, another ongoing effort to compile a database of active faults in the Iberian region.
The SHARE Iberian active fault database synthesizes a wide range of geological and geophysical observations on active seismogenic sources, and incorporates existing compilations (e.g., Cabral, 1995; Silva et al., 2008), original data contributed directly from researchers, data compiled from the literature, parameters estimated using empirical and analytical relationships, and, where necessary, parameters derived using expert judgment. The Iberian seismogenic source model derived for SHARE will be the first regional-scale source model for Iberia that includes fault data and follows an internationally standardized approach (Basili et al., 2008; 2009). This model can be used in both seismic hazard and risk analyses and will be appropriate for use in Iberian- and European-scale assessments
Parasites of the Reintroduced Iberian Lynx (Lynx pardinus) and Sympatric Mesocarnivores in Extremadura, Spain.
The Iberian lynx (Lynx pardinus) is one of the most endangered felid species in the world. Conservation efforts have increased its population size and distribution and reinforced their genetic diversity through captive breeding and reintroduction programmes. Among several threats that the Iberian lynx faces, infectious and parasitic diseases have underlined effects on the health of their newly reintroduced populations, being essential to identify the primary sources of these agents and assess populations health status. To achieve this, 79 fresh faecal samples from Iberian lynx and sympatric mesocarnivores were collected in the reintroduction area of Extremadura, Spain. Samples were submitted to copromicroscopic analyses to assess parasite diversity, prevalence, and mean intensity of parasite burden. Overall, 19 (24.1%, ±15.1-35.0) samples were positive for at least one enteric parasite species. Parasite diversity and prevalence were higher in the Iberian lynx (43.8%) compared with the others mesocarnivores under study (e.g., the red fox Vulpes vulpes and the Egyptian mongoose Herpestes ichneumon). Ancylostomatidae and Toxocara cati were the most prevalent (15.6%) parasites. Obtained results revealed that Iberian lynx role as predator control might have reduced parasite cross-transmission between this felid and mesocarnivores due to their decreasing abundances. Surveillance programs must include regular monitoring of this endangered felid, comprising mesocarnivores, but also domestic/feral and wild cat communities.This research was funded by the European Union through its LIFE project Life + IBERLINCE (LIFE + 10NAT/ES/570) “Recuperación de la distribución histórica del lince ibérico (Lynx pardinus) en España y Portugal”. R. T. Torres is funded by national funds (OE), through FCT—Fundação para a Ciência e a Tecnologia, I.P., in the scope of the framework contract foreseen in the numbers 4, 5, and 6 of the article 23, of the Decree-Law 57/2016, of 29 August, changed by Law 57/2017, of 19 July. Thanks are due to FCT/MCTES for the financial support to CESAM (UIDP/50017/2020 + UIDB/50017/2020) and CIISA Project UIDB/00276/2020 through national funds.S
Perfil clínico-epidemiológico de pacientes cirróticos internados em hospital público de referência do estado de Roraima
Introduction: Liver cirrhosis is a multifactorial preventable disease, considered the main cause of chronic liver disease and it is associated with increased morbimortality and reduced quality of life. Objective: To characterize the clinical epidemiological profile of hospitalized patients with hepatic cirrhosis at the General Hospital of Roraima. Methods: Retrospective observational study of 37 medical records of patients with liver cirrhosis who were admitted in the General Hospital of Roraima - Boa Vista-RR from January 1st, 2017 to December 31st, 2017. Results: The mean age was 54.2 years, and the sample was predominantly male (68%) and brown (78%). Most common etiologies: alcohol in 41%, hepatitis C virus (HCV) in 14%, alcohol + HCV in 5% and alcohol + hepatitis B virus (HBV) in 5% of hospitalizations. Hospitalizations occurred due to Upper gastrointestinal bleeding (UGB) in 33%; hepatic encephalopathy (HE) in 32%; and ascites in 21%. The mean duration of hospitalizations was 11.5 days. Child-Pugh A classification in 2%, Child-Pugh B in 14% and Child- Pugh C in 54% of the cases. The mortality rate in 1 year was 70%, infection causes were responsible in 38% (pulmonary, spontaneous bacterial peritonitis, among others). Of the 19 patients who survived the first hospitalization, 74% returned within 1 year. Conclusion: The main etiology of cirrhosis was alcoholism, followed by HCV infection. The hospitalizations occurred due to UGB, HE and ascites. Re-hospitalization rate was 74% and mortality rate was 70% in 1 year.Introdução: A cirrose hepática é uma doença evitável multifatorial, considerada a principal doença crônica do fígado e associada a aumento da morbimortalidade e reduzida qualidade de vida. Objetivo: Caracterizar o perfil clínico-epidemiológico de pacientes internados com cirrose hepática no Hospital Geral de Roraima. Métodos: Estudo observacional, retrospectivo, de revisão de 37 prontuários de pacientes com diagnóstico de cirrose hepática que foram internados no Hospital Geral de Roraima - Boa Vista-RR no período de 01 de janeiro de 2017 a 31 de dezembro de 2017. Resultados: A idade média foi de 54,2 anos, sendo a amostra composta predominantemente por homens (68%) e etnia parda (78%). Etiologias mais comuns: álcool em 41%, vírus da hepatite C (VHC) em 14%, álcool + VHC em 5% e álcool + vírus da hepatite B (VHB) em 5% das internações. As hospitalizações ocorreram por hemorragia digestiva alta (HDA) em 33%; encefalopatia hepática (EH) em 32%; e ascite em 21%. A duração média das internações foi de 11,5 dias. Classificação Child-Pugh A em 2%, B em 14% e C em 54% dos casos. A taxa de mortalidade em 1 ano foi de 70%, decorrente em 38% dos casos de infecções (pulmonares, peritonite bacteriana espontânea, dentre outras). Dos 19 pacientes que sobreviveram à primeira internação, 74% reinternaram em 1 ano. Conclusão: A principal etiologia da cirrose foi o alcoolismo, seguido da infecção pelo VHC. As internações ocorreram por HDA, EH e ascite, com taxa de reinternação de 74% e mortalidade de 70% em 1 ano
Anesthesia of Epinephelus marginatus with essential oil of Aloysia polystachya: an approach on blood parameters
This study investigated the anesthetic potential of the essential oil (EO) of Aloysia polystachya in juveniles of dusky grouper (Epinephelus marginatus). Fish were exposed to different concentrations of EO of A. polystachya to evaluate time of induction and recovery from anesthesia. In the second experiment, fish were divided into four groups: control, ethanol and 50 or 300 mu L L-1 EO of A. polystachya, and each group was submitted to induction for 3.5 min and recovery for 5 or 10 min. The blood gases and glucose levels showed alterations as a function of the recovery times, but Na+ and K+ levels did not show any alteration. In conclusion, the EO from leaves of A. polystachya is an effective anesthetic for dusky grouper, because anesthesia was reached within the recommended time at EO concentrations of 300 and 400 mu L L-1. However, most evaluated blood parameters showed compensatory responses due to EO exposure.Fundacao de Amparo a Pesquisa do Estado do Rio Grande do Sul/Programa de Apoio a Nucleos de Excelencia (FAPERGS/PRONEX) [10/0016-8]; Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq) [470964/2009-0]; Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior, Brazil (CAPES)info:eu-repo/semantics/publishedVersio
Global declines in coral reef calcium carbonate production under ocean acidification and warming
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