The vernacular house between the Cávado and the Ave, Portugal

Publicado em "Vernacular heritage and earthen architecture : contributions for sustainable development", ISBN 978-1-138-00083-4With acknowledged authenticity and cultural heritage value, rural vernacular construction of Entre-Douro-e-Minho represents the results of the centuries-old relation between men and available natural resources. Abandoned or victim of armful interventions, this unique heritage acquired economi- cal value by the growing interest on rural environment and life. It represents a mean to economical and social boosting of these depressed areas, but at the same time exposing them to the threatening lack of knowledge and property speculation. In order to protect and prevent future damages to this fragile herit- age, it’s fundamental the study and identification of its identity and technical-constructive key features. This paper presents the results of a fieldwork study performed between the Cávado and Ave rivers, which aimed to identify morfo-typologies, materials and construction techniques of the existent schist heritage. The data collected aims to contribute to its preservation and to assist technicians in future rehabilitation projects in the area

Use of manganese oxides recovered from spent batteries in electrocatalysis of oxygen reduction reaction in alkaline medium

The oxygen reduction reaction was studied in alkaline media using manganese oxides obtained from spent batteries as electrocatalysts. Three processes were used to recover manganese oxides from spent batteries. The particles obtained were in the range from 8 to 11 nm. The electrochemical experiments indicated a good electrocatalytic activity toward oxygen reduction using the different samples and showing approximately a direct transference of 4 electrons during the process. Even though all the processes were efficient, the best result was observed for the prepared sample using reactants of low cost.FAPESPCNPqCoordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES)UFAB

The construction of the transhumance territory of the Gerês-Xurés: Vernacular heritage identification, analysis and characterization

In order to ensure survival, the rural populations of the Gerês-Xurés mountain range transboundary region developed, over centuries, a very specific system of vertical transhumance. Focus on making the most out of their natural landscape harsh conditions, human intervention shaped the territory, and gave birth to the existent and very authentic vernacular heritage, that has in the corbelled dome building technologies one of its most characteristic identity features. In the pursuit of fertile land, villages were scattered in small and compact settlements, built at lower altitude and occupied all year long. The surrounding mountain’s slopes were turned into farming terraces, and the high-altitude plateaus were for livestock and farming, thru temporary settlements built in corbelled dome structures. These vital points were interconnect by a dense network of paths and masonry walls. Although the resemblance between most of the region permanent settlements, the temporary nuclei, due to each mountain particular features, show a large morphological and functional diversity, from complex structures, like the “brandas” or the “brandas e inverneiras” system, to very simple pasture areas, like the “currais”. Understanding the high potential of this endanger vernacular heritage is a key point for its preservation, as well as its recognition by the scientific community and society in general. A previous study aimed at the “brandas” morphological and constructive characterization was presented at the Rehabend 2016. This follow-up study is focus on, in a first level, the identification and characterization of the general system main features, and, in a second level, the evaluation of this vernacular heritage main preservation threats. The research, based on case studies analysed thru fieldwork surveys, geometrical and constructive, and literature support, allowed to identify the main morphological and typological features related to the heritage elements that take part in this occupation system, and are discussed in this paper.Portuguese Science and Technology Foundation for the scholarships granted (SFRH/BD/ 86704/2012 and SFRH/BD/112646/2015). This work was supported by FCT, within ISISE, project UID/ECI/04029/201

Non-Abelian Geometric Phases and Conductance of Spin-3/2 Holes

Angular momentum $J=3/2$ holes in semiconductor heterostructures are showed to accumulate nonabelian geometric phases as a consequence of their motion. We provide a general framework for analyzing such a system and compute conductance oscillations for a simple ring geometry. We also analyze a figure-8 geometry which captures intrinsically nonabelian interference effects.Comment: 4 pages, 3 figures (encapsulated PostScript) Replaced fig. 1 and fig.

A new experiment for the determination of the 18F(p,alpha) reaction rate at nova temperatures

The 18F(p,alpha) reaction was recognized as one of the most important for gamma ray astronomy in novae as it governs the early 511 keV emission. However, its rate remains largely uncertain at nova temperatures. A direct measurement of the cross section over the full range of nova energies is impossible because of its vanishing value at low energy and of the short 18F lifetime. Therefore, in order to better constrain this reaction rate, we have performed an indirect experiment taking advantage of the availability of a high purity and intense radioactive 18F beam at the Louvain La Neuve RIB facility. We present here the first results of the data analysis and discuss the consequences.Comment: Contribution to the Classical Novae Explosions conference, Sitges, Spain, 20-24 May 2002, 5 pages, 3 figure

Conservation of oceanic island floras: Present and future global challenges

Currentthreatstotheplanet’sbiodiversityareunprecedented,andtheyparticularlyimperilinsular floras.Inthisinvestigation,weusethethreatfactorsidentifiedbytheMillenniumEcosystem Assessmentasthemaindriversofbiodiversitylossonislandstodefineandrank13current,continuing threatstotheplantdiversityofninefocalarchipelagoswherevolcanicorigin(orintheSeychellesa prolongedisolationafteracontinentalorigin)hasproducedahighdegreeofendemicityandfragilityin the faceofhabitatalteration.Wealsoconductaglobalendangermentassessmentbasedonthe numbersofinsularendemicplantsintheendangered(EN)andcriticallyendangered(CR)IUCN categoriesfor53islandgroupswithanestimated9951endemicplantspecies,providinga representativesampleoftheworld’sinsularsystemsandtheirfloristicrichness.Ouranalysesindicate that isolationdoesnotsignificantlyinfluenceendangerment,butplantendemicsfromverysmall islandsaremoreoftencriticallyendangered.Weestimatethatbetween3500and6800oftheestimated 70,000 insularendemicplantspeciesworldwidemightbehighlythreatened(CR+EN)andbetweenca. 2000 and2800ofthemincriticaldangerofextinction(CR).Basedontheseanalyses,andona worldwideliteraturereviewofthebiologicalthreatfactorsconsidered,weidentifychallenging questionsforconservationresearch,asking(i)whatarethemosturgentprioritiesfortheconservation of insularspeciesandfloras,and(ii)withtheknowledgeandassetsavailable,howcanweimprovethe impactofconservationscienceandpracticeonthepreservationofislandbiodiversity?Ouranalysis indicatesthatthesynergisticactionofmanythreatfactorscaninducemajorecologicaldisturbances, leadingtomultipleextinctions.Wereviewweaknessesandstrengthsinconservationresearchand managementintheninefocalarchipelagos,andhighlighttheurgentneedforconservationscientiststo shareknowledgeandexpertise,identifyanddiscusscommonchallenges,andformulatemulti- disciplinaryconservationobjectivesforinsularplantendemicsworldwide.Toourknowledge,thisisthe mostup-to-dateandcomprehensivesurveyyettoreviewthethreatfactorstonativeplantsonoceanic islandsanddefinepriorityresearchquestions

Improved X-ray detection and particle identification with avalanche photodiodes

Avalanche photodiodes are commonly used as detectors for low energy x-rays. In this work we report on a fitting technique used to account for different detector responses resulting from photo absorption in the various APD layers. The use of this technique results in an improvement of the energy resolution at 8.2 keV by up to a factor of 2, and corrects the timing information by up to 25 ns to account for space dependent electron drift time. In addition, this waveform analysis is used for particle identification, e.g. to distinguish between x-rays and MeV electrons in our experiment.Comment: 6 pages, 6 figure

Molecular excitation in the Interstellar Medium: recent advances in collisional, radiative and chemical processes

We review the different excitation processes in the interstellar mediumComment: Accepted in Chem. Re

Potencial de irrigação de pequenas bacias hidrográficas do Piauí.

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