Virtual Models for Crystallography Teaching in Mineralogy: Some Suggestions

[Abstract] Crystallography concepts are usually among the most demanding subjects for Mineralogy students. Traditional onsite teaching of Mineralogy starts with physical models of crystal polyhedra and frequently also includes the observation of models of crystal structures. These teaching strategies could be difficult to implement under pandemic situations like the present one. But they also have other disadvantages under the usual access conditions as their use by the students is restricted by the number of students in relation to the number of models and by the availability of the models and teaching staff. Additionally, onsite teaching can pose challenges to both students and teachers with temporal or permanent disabilities. We consider here some possibilities of teaching with virtual models of crystal polyhedra, twinning, and crystal structures, based on some of the available freeware options and considering the main concepts taught in the usual Mineralogy syllabus.Portugal. Fundação para a Ciência e a Tecnologia; UIDB/04509/2020Portugal. Fundação para a Ciência e a Tecnologia; UIDB/04028/2020Xunta de Galicia; ED431B 2018/47Xunta de Galicia; R2017/00

Remote operations could be the future for Earth Sciences teaching: a speculative discussion

[Abstract] The current COVID-19 pandemic has created havoc in the regular workings of many institutions, such as those dedicated to teaching; therefore, there is an urge for alternatives to traditional face-to-face teaching. However, for certain subjects, such as Earth Sciences, distance-teaching approaches could be seen as counterintuitive to the essential foundations of the subject (where empirical information, especially from fieldwork, is considered paramount for its foundation and growth). In this work, we consider remote operations that could complement, improve, and perhaps even replace the traditional approach for teaching Earth Sciences, potentially producing better learning outcomes, even in relation to laboratory and fieldwork, including studies involving locations outside of planet Earth. Additionally, we consider the possible advantages for other professional settings related to this area, such as those concerning terrain characterization for engineering works, mineral resources, and environmental studies, as well as possible support for space missions and stations in other astronomical bodies (where mineral exploration and extraction could be developed and, hence, benefit from remote operations).Portugal. Fundação para a Ciência e a Tecnologia; FCT-UIDB/04509/2020Portugal. Fundação para a Ciência e a Tecnologia; FCT-UIDB/04028/2020Xunta de Galicia; ED431B 2018/47Xunta de Galicia; R2017/00

Wireless vehicular communications for automatic incident detection and recovery

Incident detection is the process by which an incident is brought to the attention of traffic operators in order to design and activate a response plan. To minimize the detection time is crucial to mitigate the incident severity for victims as well to reduce the risk of secondary crashes. Automated incident information dissemination and traffic conditions is useful to alert in-route drivers to decide alternative routes on unexpected traffic congestion and may be also used for the incident recovery process, namely to optimize the response plan including the “nearest” rescue teams, thereby shortening their response times. Wireless vehicular communications, notably the emergent IEEE 802.11p protocol, is the enabling technology providing timely, dependable and secure properties that are essential for the devised target application. However, there are still some open issues with vehicular communications that require further research efforts. This paper presents an overview of the state of the art in wireless vehicular communications and describes the field operational tests proposed within the scope of the upcoming FP7 project ICSI - Intelligent Cooperative Sensing for Improved traffic efficiency

Zoneamento de risco agroclimático para o limão (citrus aurantifolia) na bacia hidrográfica do Rio Paraná III, Brasil

A lima ácida Tahiti está entre as dez variedades de frutas mais importantes produzidas e consumidas no Brasil, sendo o quinto maior produtor mundial. O objetivo desse trabalho foi realizar o zoneamento de risco agroclimático para o limoeiro (Citrus aurantifolia) na bacia do Rio Paraná III. Foram elaborados mapas temáticos por meio de interpolação e regressões, além de gráficos de probabilidade para a análise do risco. O risco agroclimático para o limoeiro foi pautado nas exigências da espécie, sendo estas, precipitação, deficiência hídrica, temperatura do ar média e máxima, unidade térmica/graus dia e risco de geada. A maior parte da área da bacia foi apta para o cultivo. Não houve áreas inaptas, apenas restritas demonstrando assim, o potencial para a produção na região.El limonero es una de las variedades de frutas más importantes de Brasil, considerado el quinto mayor productor mundial. El propósito de este estudio fue realizar la zonificación del riesgo agroclimático para el limón (Citrus aurantifolia) en la cuenca del río Paraná III. Se elaboraron mapas técnicos mediante interpolación y regresiones, y gráficos para las probabilidades de análisis de riesgos. El riesgo agroclimático para el limón se estableció de acuerdo con los requisitos de la especie, tales como precipitación, deficiencia de agua, temperatura media y máxima del aire, unidad térmica / grados días y riesgo de heladas. La mayor parte del área de la cuenca era apta para el cultivo. No se encontraron áreas inactivas para el cultivo, solo restringir, exhibiendo un potencial considerable para el cultivo de limón, en la región de estudio.The lemon tree is one of the most important variety of fruits in Brazil, considered the fifth largest world producer. The purpose of this study was to carry out agroclimatic risk zoning for lemon (Citrus aurantifolia) in the basin of Paraná River III. Technical maps through interpolation and regressions, and graphics for risks analysis probabilities were elaborated. The agroclimatic risk for lemon was established according to the species requirements, such as precipitation, water deficiency, average and maximum air temperature, thermal unit/degrees days and risk of frost. Larger region in the basin is recommended for cultivation of lemon. It was not found inapt areas for cultivation, only restrict, exhibiting considerable potential for cultivation of lemon, in the region of study

Moderate but not low intensity aerobic exercise promotes postexercise hypotension in older adults with hypertension and regular exercise participation

The reduction in blood pressure as a result of a single session of exercise seems especially relevant for assisting in the control of blood pressure during day-time periods when blood pressure is typically at its highest levels and to allow the performance of activities of daily living at lower levels of blood pressure. Despite evidence related to post-exercise blood pressure reduction as a result of a single session of aerobic exercise in adults with hypertension, there is a lack of studies enrolling adults with hypertension and regular exercise participation. The results could be less predictable in this group of subjects, because the magnitude of the acute effect could be lower due to a better blood pressure control in response to the regular exercise practice. Previous studies showed that exercise intensity could influence the blood pressure response after exercise cessation. To compare the effects of low (30% heart rate reserve, HRres) and moderate (60% HRres) intensity on the blood pressure response immediately following aerobic exercise in older adults with hypertension and regular exercise participation. We aim to determine whether the phenomenon designated as postexercise hypotension, i.e. the transient reduction in blood pressure in the period after exercise to values less than those observed before exercise, is modulated by exercise intensity. 19 older adults (12 women; age: 66.0±1.7 years; weight: 65.8±8.5 kg; BMI: 24.8±2.6 kg/m2) who exercise at least 3 times per week on a regular basis, completed two randomly assigned aerobic exercise bouts at low (30% heart rate reserve, HRres) and moderate (60% HRres) lasting 30 minutes each. The exercise bouts were performed in the morning (9 a.m.), 7 days apart from each other, on a treadmill.Anthropometric variables, medication status and clinical history were collected. Blood pressure was measured at baseline after 10 min of rest, at 10 min after exercise, and at every hour until 6 hours post exercise. Over the course of 6 hours, systolic and diastolic blood pressure did not change significantly after the low intensity exercise bout in comparison to the baseline values (134.9±14.5 mmHg and 80.0±8.0 mmHg, respectively). In the moderate exercise bout, the systolic pressure at 1 hour (125.3±15.3 mmHg, p=0.029) and up to 5 (126.2±17.1 mmHg, p=0.041) and 6 hours (126.3±13.8 mmHg, p=0.040) postexercise was significantly lower in comparison with baseline (135.0±16.0 mmHg). Diastolic pressure did not change. A single session of moderate aerobic exercise acutely reduces blood pressure in hypertensive older adults with regular exercise practice and may be a nonpharmacological coadjuvant tool to control hypertension in this age group. The intensity of exercise seemed to be a key factor to post-exercise blood pressure reduction. Even hypertensive subjects with regular exercise practice benefit from an acute bout of exercise. These results add evidence supporting the importance of aerobic exercise as a non-pharmacological strategy to control hypertension.info:eu-repo/semantics/publishedVersio

Microstructural analysis of carbon nanomaterials produced from pyrolysis/combustion of Styrene-Butadiene-Rubber (SBR)

Styrene-Butadiene-Rubber (SBR) is a synthetic rubber copolymer used to fabricate several products. This study aims to demonstrate the use of SBR as feedstock for carbon nanomaterials (nanofibers and nanotubes) growth, and therefore to establish a novel process for destination of waste products containing SBR. A three stage electrically heated flow reactor was used. Small pellets of rubber were pyrolyzed at a temperature of 1000 ºC. The pyrolyzates were mixed with oxygen-containing gases and were burned. The products of combustion were used to synthesize the carbon nanomaterials (CNMs) at the presence of a catalyst. CNMs have a wide range of potential applications due to their extraordinary mechanical, thermal and electrical properties. Produced materials were characterized by SEM and TEM, whereas combustion products were assessed using GC. Results showed that CNMs with outer diameters of 30-100 nm and lengths of about 30 µm were formed. Therefore, it was demonstrated that waste products containing SBR can be used to generate CNMs which are value-added products of intense technological interest.CNPQCoordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES

Geological Materials as Cultural Markers of Water Resources

[Abstract] Water has always been a critical resource for humans and climate change could aggravate supply problems. In this context, groundwater could be an important reservoir of water, especially given the dispersion of places where it can be obtained and the widespread occurrence of surface marks (springs). Historically, places where groundwater is available have been marked by humans using built structures, with stone materials having a major role. These cultural objects tend to become a part of the collective memory and the historical record (when available) and frequently they stay on the original site along time (hence “marking a spot” for groundwater). However, the development of major water supply structures, especially in the 20th century, promoted the negligence of these ancient water sources. We present a general defense of the importance of recording and preserving cultural stone related to water sources, preferably in the original sites. Conservation of groundwater-related structures could help in the future exploration of this geological resource and converge with historical information on the fountains’ discharge, with geological studies of the terrains and geochemical features of the groundwaters involved, in order to characterize the hydrogeological systems and their potential future use (including the preservation of water quality and properties). These studies could promote a synergetic conservation of both heritage and water.Portugal. Fundação para a Ciência e a Tecnologia; UIDB/04509/2020Portugal. Fundação para a Ciência e a Tecnologia; UIDB/04028/2020Xunta de Galicia; ED431B 2018/47Xunta de Galicia; R2017/008The Lab2PT-Landscapes, Heritage and Territory laboratory—UIDB/04509/2020 is supported by the Portuguese FCT—“Fundação para a Ciência e a Tecnologia”. The authors also gratefully acknowledge the support of the CERENA (funded by a strategic project of the FCT UIDB/04028/2020) and the LAMPIST of the DECivil, Instituto Superior Técnico, University of Lisbon, Portugal. The University Institute of Geology of the University of A Coruña (Spain) receives support from the Xunta de Galicia from the program “Consolidación y estructuración de unidades de investigación competitivas: Grupos de potencial de crecimiento” (ED431B 2018/47) and Redes de investigación (R2017/008). We also thank the IACOBUS Program from the European Strategic Group of Territorial Cooperation Galicia/North of Portugal for support for the last authorThe Lab2PT-Landscapes, Heritage and Territory laboratory—UIDB/04509/2020 is supported by the Portuguese FCT—“Fundação para a Ciência e a Tecnologia”. The authors also gratefully acknowledge the support of the CERENA (funded by a strategic project of the FCT UIDB/04028/2020) and the LAMPIST of the DECivil, Instituto Superior Técnico, University of Lisbon, Portugal. The University Institute of Geology of the University of A Coruña (Spain) receives support from the Xunta de Galicia from the program “Consolidación y estructuración de unidades de investigación competitivas: Grupos de potencial de crecimiento” (ED431B 2018/47) and Redes de investigación (R2017/008). We also thank the IACOBUS Program from the European Strategic Group of Territorial Cooperation Galicia/North of Portugal for support for the last autho

Efeito do cálcio sobre algumas características biofísicas e morfológicas de plantas de mliho BRS-4154 submetidas ao alagamento do solo

objetivo deste trabalho foi avaliar o efeito de diferentes níveis, fontes e formas de aplicação do cálcio no solo, em condições de alagamento, no comportamento de algumas características biofísicas e morfológicas de plantas de milho, cultivar Saracura, medidas na floração. O experimento foi conduzido em condições controladas de casa de vegetação, na Embrapa Milho e Sorgo. As sementes utilizadas foram de milho Saracura BRS 4154, ciclo 14; o solo empregado foi de várzea. Os tratamentos utilizados foram: duas fontes de cálcio (CaCl2 , 300 kg ha-1 e gesso, 500 e 1500 kg ha-1) e três formas de aplicação (incorporado nos primeiros 8 cm da superfície, em todo o solo e sobre a superfície), em condições normais de irrigação e sob alagamento iniciado no estádio V6, permanecendo até a floração. Utilizou-se um delineamento inteiramente casualizado e as análises foram feitas na floração, avaliando-se área foliar, acúmulo de matéria seca da parte aérea da planta, eficiência fotoquímica do fotossistema II, características biofísicas, tais como, resistência estomática e transpiração, algumas características morfológicas, como porosidade de raízes e raízes adventícias, intervalo entre florescimento masculino e feminino e análise do teor de macronutrientes

Portable rainfall simulator: evaluation and suitability of plot geometry to improve rainfall uniformity

Os simuladores de chuva são uma importante ferramenta para várias áreas das geociências. Os autores da maioria dos estudos publicados com simuladores de chuva tentam conseguir uma distribuição da precipitação o mais uniforme possível. Contudo, sendo tal muito difícil, são utilizados índices que visam aferir a maior ou menor uniformidade da precipitação na área da parcela em estudo. Um dos mais utilizados é o coeficiente de uniformidade de Christiansen. Neste trabalho, foram analisadas possíveis alterações da geometria da área molhada da parcela para melhorar a uniformidade da precipitação. Isso foi avaliado através da intensidade da precipitação e do coeficiente de uniformidade de Christiansen na área molhada da parcela. Os testes foram realizados utilizando dois modelos de bicos pulverizadores e diferentes pressões de operação. A geometria inicial da parcela era de 0,7 x 1,0 m (0.70 m2). Os resultados do coeficiente de uniformidade de Christiansen foram classificados como baixos, enquanto o melhor desempenho em termos de uniformidade de precipitação foi obtido a uma pressão de 48,3 kPa. A precipitação com menor uniformidade foi observável próximo dos limites externos da parcela. Com base nos melhores resultados do coeficiente de uniformidade de Christiansen, propôs-se reduzir a área útil da parcela experimental de 0,70 para 0,56 m2, levando a uma intensidade de precipitação de 114.07 e 149.20 mm·h−1 e a um coeficiente de uniformidade de Christiansen de 81,6 e 83,8% para os dois modelos de bicos pulverizadores. Os resultados mostraram que proceder com ajustes na geometria da parcela pode conduzir, de forma simples e rápida, a uma maior uniformidade da precipitação artificial.LA/P/0069/2020info:eu-repo/semantics/publishedVersio