Diversidade subgenérica de Brasilonema (Cyanobacteria, Scytonemataceae)

The recently described scytonematoid cyanobacterial genus Brasilonema is known mainly from tropical and subtropical rain forests (Mata Atlântica) of southeastern Brazil, where it occurs in aerophytic wooden, stony and iron substrates. This genus was defined according to both molecular and morphological criteria. The type species B. bromeliae was described from the specialized habitat: it grows in phytothelmes, epiphytic on both living and died leaves within the rosettes of large bromeliad plants slightly above or in the zone of the water level. The genus Brasilonema is evidently widely distributed in coastal forests of São Paulo State, where it occurs also in remarkable diversity. According to our results, this genus currently comprises seven taxa, which are distinct by different morphology and ecological characteristics.O gênero scytonematóide de Cyanobacteria, Brasilonema, foi descrito recentemente e é conhecido principalmente de florestas tropicais e subtropicais (Mata Atlântica) da região sudeste do Brasil. Ocorre sobre substratos aerofíticos como madeira, pedra e ferro e foi definido de acordo com critérios moleculares e morfológicos. A espécie-tipo, B. bromeliae, foi coletada em um habitat muito específico: epífita em folhas de bromélias, dentro das rosetas, próximo do nível da água, ou ainda em folhas secas destas plantas. O gênero Brasilonema é amplamente distribuído nas florestas costeiras do Estado de São Paulo, onde ocorre em alta diversidade morfológica. De acordo com nossos resultados, este gênero atualmente compreende sete táxons distintos com base nas diferenças morfológicas e características ecológicas

Noncommutative Spheres and Instantons

We report on some recent work on deformation of spaces, notably deformation of spheres, describing two classes of examples. The first class of examples consists of noncommutative manifolds associated with the so called $\theta$-deformations which were introduced out of a simple analysis in terms of cycles in the $(b,B)$-complex of cyclic homology. These examples have non-trivial global features and can be endowed with a structure of noncommutative manifolds, in terms of a spectral triple (\ca, \ch, D). In particular, noncommutative spheres $S^{N}_{\theta}$ are isospectral deformations of usual spherical geometries. For the corresponding spectral triple (\cinf(S^{N}_\theta), \ch, D), both the Hilbert space of spinors \ch= L^2(S^{N},\cs) and the Dirac operator $D$ are the usual ones on the commutative $N$-dimensional sphere $S^{N}$ and only the algebra and its action on $\ch$ are deformed. The second class of examples is made of the so called quantum spheres $S^{N}_q$ which are homogeneous spaces of quantum orthogonal and quantum unitary groups. For these spheres, there is a complete description of $K$-theory, in terms of nontrivial self-adjoint idempotents (projections) and unitaries, and of the $K$-homology, in term of nontrivial Fredholm modules, as well as of the corresponding Chern characters in cyclic homology and cohomology.Comment: Minor changes, list of references expanded and updated. These notes are based on invited lectures given at the ``International Workshop on Quantum Field Theory and Noncommutative Geometry'', November 26-30 2002, Tohoku University, Sendai, Japan. To be published in the workshop proceedings by Springer-Verlag as Lecture Notes in Physic

Catalog of Radio Galaxies with z>0.3. I:Construction of the Sample

The procedure of the construction of a sample of distant ($z>0.3$) radio galaxies using NED, SDSS, and CATS databases for further application in statistical tests is described. The sample is assumed to be cleaned from objects with quasar properties. Primary statistical analysis of the list is performed and the regression dependence of the spectral index on redshift is found.Comment: 9 pages, 6 figures, 2 table

Carbon uptake by mature Amazon forests has mitigated Amazon nations' carbon emissions

Background: Several independent lines of evidence suggest that Amazon forests have provided a significant carbon sink service, and also that the Amazon carbon sink in intact, mature forests may now be threatened as a result of different processes. There has however been no work done to quantify non-land-use-change forest carbon fluxes on a national basis within Amazonia, or to place these national fluxes and their possible changes in the context of the major anthropogenic carbon fluxes in the region. Here we present a first attempt to interpret results from groundbased monitoring of mature forest carbon fluxes in a biogeographically, politically, and temporally differentiated way. Specifically, using results from a large long-term network of forest plots, we estimate the Amazon biomass carbon balance over the last three decades for the different regions and nine nations of Amazonia, and evaluate the magnitude and trajectory of these differentiated balances in relation to major national anthropogenic carbon emissions. Results: The sink of carbon into mature forests has been remarkably geographically ubiquitous across Amazonia, being substantial and persistent in each of the five biogeographic regions within Amazonia. Between 1980 and 2010, it has more than mitigated the fossil fuel emissions of every single national economy, except that of Venezuela. For most nations (Bolivia, Colombia, Ecuador, French Guiana, Guyana, Peru, Suriname) the sink has probably additionally mitigated all anthropogenic carbon emissions due to Amazon deforestation and other land use change. While the sink has weakened in some regions since 2000, our analysis suggests that Amazon nations which are able to conserve large areas of natural and semi-natural landscape still contribute globally-significant carbon sequestration. Conclusions: Mature forests across all of Amazonia have contributed significantly to mitigating climate change for decades. Yet Amazon nations have not directly benefited from providing this global scale ecosystem service. We suggest that better monitoring and reporting of the carbon fluxes within mature forests, and understanding the drivers of changes in their balance, must become national, as well as international, priorities

Estimating the global conservation status of more than 15,000 Amazonian tree species

Estimates of extinction risk for Amazonian plant and animal species are rare and not often incorporated into land-use policy and conservation planning. We overlay spatial distribution models with historical and projected deforestation to show that at least 36% and up to 57% of all Amazonian tree species are likely to qualify as globally threatened under International Union for Conservation of Nature (IUCN) Red List criteria. If confirmed, these results would increase the number of threatened plant species on Earth by 22%. We show that the trends observed in Amazonia apply to trees throughout the tropics, and we predict thatmost of the world’s >40,000 tropical tree species now qualify as globally threatened. A gap analysis suggests that existing Amazonian protected areas and indigenous territories will protect viable populations of most threatened species if these areas suffer no further degradation, highlighting the key roles that protected areas, indigenous peoples, and improved governance can play in preventing large-scale extinctions in the tropics in this century

Variation in stem mortality rates determines patterns of above-ground biomass in Amazonian forests: implications for dynamic global vegetation models

Understanding the processes that determine above-ground biomass (AGB) in Amazonian forests is important for predicting the sensitivity of these ecosystems to environmental change and for designing and evaluating dynamic global vegetation models (DGVMs). AGB is determined by inputs from woody productivity [woody net primary productivity (NPP)] and the rate at which carbon is lost through tree mortality. Here, we test whether two direct metrics of tree mortality (the absolute rate of woody biomass loss and the rate of stem mortality) and/or woody NPP, control variation in AGB among 167 plots in intact forest across Amazonia. We then compare these relationships and the observed variation in AGB and woody NPP with the predictions of four DGVMs. The observations show that stem mortality rates, rather than absolute rates of woody biomass loss, are the most important predictor of AGB, which is consistent with the importance of stand size structure for determining spatial variation in AGB. The relationship between stem mortality rates and AGB varies among different regions of Amazonia, indicating that variation in wood density and height/diameter relationships also influences AGB. In contrast to previous findings, we find that woody NPP is not correlated with stem mortality rates and is weakly positively correlated with AGB. Across the four models, basin-wide average AGB is similar to the mean of the observations. However, the models consistently overestimate woody NPP and poorly represent the spatial patterns of both AGB and woody NPP estimated using plot data. In marked contrast to the observations, DGVMs typically show strong positive relationships between woody NPP and AGB. Resolving these differences will require incorporating forest size structure, mechanistic models of stem mortality and variation in functional composition in DGVMs

Search for heavy resonances decaying into a vector boson and a Higgs boson in final states with charged leptons, neutrinos, and b quarks

Peer reviewe

Search for high-mass diphoton resonances in proton-proton collisions at 13 TeV and combination with 8 TeV search

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Search for black holes and other new phenomena in high-multiplicity final states in proton-proton collisions at root s=13 TeV

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