A water level relationship between consecutive gauge stations along Solim\~oes/Amazonas main channel: a wavelet approach

Gauge stations are distributed along the Solim\~oes/Amazonas main channel to monitor water level changes over time. Those measurements help quantify both the water movement and its variability from one gauge station to the next downstream. The objective of this study is to detect changes in the water level relationship between consecutive gauge stations along the Solim\~oes/Amazonas main channel, since 1980. To carry out the analyses, data spanning from 1980 to 2010 from three consecutive gauges (Tefe, Manaus and Obidos) were used to compute standardized daily anomalies. In particular for infra-annual periods it was possible to detect changes for the water level variability along the Solim\~oes/Amazonas main channel, by applying the Morlet Wavelet Transformation (WT) and Wavelet Cross Coherence (WCC) methods. It was possible to quantify the waves amplitude for the WT infra-annual scaled-period and were quite similar to the three gauge stations denoting that the water level variability are related to the same hydrological forcing functions. Changes in the WCC was detected for the Manaus-Obidos river stretch and this characteristic might be associated with land cover changes in the floodplains. The next steps of this research, will be to test this hypotheses by integrating land cover changes into the floodplain with hydrological modelling simulations throughout the time-series

Influência do espaçamento na produção volumétrica e qualidade da madeira de Mimosa scabrella Benth. e Eucalyptus viminalis Labill.

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Density functional investigations of defect induced mid-gap states in graphane

We have carried out ab initio electronic structure calculations on graphane (hydrogenated graphene) with single and double vacancy defects. Our analysis of the density of states reveal that such vacancies induce the mid gap states and modify the band gap. The induced states are due to the unpaired electrons on carbon atoms. Interestingly the placement and the number of such states is found to be sensitive to the distance between the vacancies. Furthermore we also found that in most of the cases the vacancies induce a local magnetic moment.Comment: 15 page

Efeitos da primeira poda em povoamentos jovens de Pinus elliottii var elliottii, estabelecidos na região costeira do Rio Grande do Sul.

bitstream/item/101229/1/PA-1983-Ahrens-EfeitosPrimeira.pd

Third edge for a graphene nanoribbon: A tight-binding model calculation

The electronic and transport properties of an extended linear defect embedded in a zigzag nanoribbon of realistic width are studied, within a tight binding model approach. Our results suggest that such defect profoundly modify the properties of the nanoribbon, introducing new conductance quantization values and modifying the conductance quantization thresholds. The linear defect along the nanoribbon behaves as an effective third edge of the system, which shows a metallic behavior, giving rise to new conduction pathways that could be used in nanoscale circuitry as a quantum wire.Comment: 6 pages, 6 figures. Two new figures and a few references adde

Adolescents who stay, parents who migrate: gender inequalities, resilience and coping strategies in Tajikistan

Studies on the consequences of migration often ignore the perspectives of children and adolescents who remain in the origin country while their migrant parents are absent. This is the case in Tajikistan, one of the poorest and most remittance-dependent countries in the world. Using a qualitative methodology, microethnography, we interviewed eight teenagers aged between 12 and 18, in the city of Khorugh, Tajikistan, to explore the impact of migration from their perspective. Findings reveal that these adolescents ‘understand’ the reasons for their parents’ migration in a way that both gives coherence to this migration and invests young people with resilience and coping strategies. As a result, all the young people naturalised having to live with sadness, reflecting the ‘normalisation’ of this social cost in wider Tajik society. However, the experiences and coping strategies of those interviewed are gendered; boys were more likely to ‘rationalise’ their experience and be aloof; girls more likely to express emotional upset. In practical terms, boys also received more benefits from remittances while girls reported feeling overwhelmed by domestic chores expected of them. Through this study, we contribute to the recent literature on the lived experiences and agency of non-migrant teenagers.info:eu-repo/semantics/acceptedVersio

Efeitos da primeira poda em povoamentos jovens de Pinus taeda L. estabelecidos em Mafra, SC, região do alto rio negro.

bitstream/item/101227/1/PA-1983-Abrens-EfeitoPrimeira.pd

Numerical indications on the semiclassical limit of the flipped vertex

We introduce a technique for testing the semiclassical limit of a quantum gravity vertex amplitude. The technique is based on the propagation of a semiclassical wave packet. We apply this technique to the newly introduced "flipped" vertex in loop quantum gravity, in order to test the intertwiner dependence of the vertex. Under some drastic simplifications, we find very preliminary, but surprisingly good numerical evidence for the correct classical limit.Comment: 4 pages, 8 figure