Shrub diversity in Mediterranean shrublands: Rescuer or victim of productivity?

[ENG]Aims: Unravelling the most prevalent causal direction between diversity and function in naturally recovered plant assemblages can greatly improve our understanding of the functional significance of diversity and its applications under the ongoing envi- ronmental changes. In this study, we apply a structural equation model framework to unravel the most plausible causal direction in the diversity–productivity relationship in subseral Mediterranean shrub-dominated communities. Methods: Total shrub cover (as a proxy of productivity when controlled by the time since land use cessation or the last wildfire), the number of species, and the number of functional types based on the dominant life forms (phanerophytes vs. chamaephytes), and the dominant foliar syndromes (deciduous vs. evergreen, needled vs. broad- leaved), were sampled in 195 circular plots distributed along an elevation gradient ranging from 400 to 1400 m a.s.l. in the Central Iberian Peninsula. We first explored the distribution of functional types along the elevation gradient using a non-metric multidimensional scaling (NMDS). Secondly, a structural equation model (SEM) frame- work using mixed-effects models was defined to unveil the prevalent causal direction between diversity (species and functional types) and productivity at the landscape scale. Results: Model selection using the Fisher's C information criterion supported a causal direction from total shrub cover to diversity in this landscape. Interestingly, the best supported model also supported a positive relationship between species richness and the number of functional types, which in turn is driven by the total shrub cover along the elevation gradient. Conclusions: Our results suggest that more species might not necessarily boost pro- ductivity. On the contrary, ongoing warming temperatures and aridity, which are characteristic of low elevations compared to highlands, might significantly reduce the number of species (victim rather than rescuer) through deleterious effects on productivity

EPIDEMIOLOGIA E PERFIL DE SENSIBILIDADE DOS GERMES ISOLADOS DE HEMOCULTURAS DE PACIENTES HEMATOLÓGICOS COM NEUTROPENIA FEBRIL

Introdução: A neutropenia febril (NF) é uma complicação muito freqüente nos pacientes com neoplasias hematológicas submetidos à quimioterapia. O manejo da NF permanece muito problemático especialmente pela mudança constante do espectro dos germes e da sensibilidade aos antimicrobianos. Desta forma, torna-se imprescindível conhecer a epidemiologia local das infecções associadas à NF. Objetivo: Determinar a prevalência e a sensibilidade aos antimicrobianos dos germes isolados de hemoculturas (HMC) de pacientes hematológicos com NF internados no HCPA. Métodos: Foram analisadas, retrospectivamente, todas as HMC solicitadas para pacientes com NF (contagem total de neutrófilos 38,5oC ou duas medidas >38oC em 24 horas. Comparou-se o perfil de sensibilidade das infecções em pacientescom NF em relação às demais unidades de internação clínica do hospital.Resultados: Foram solicitadas no período em estudo 2389 hemoculturas para 178 pacientes. Destas, 719 (30,1%) foram positivas sendo que este percentual subiu para 38,7% quando consideradas apenas as hemoculturas coletas sem a vigência de antibiótico. A análise dos germes isolados revelou que a maioria das infecções foi causada por Bacilos Gram-negativos (53,8%) seguido pelos Cocos Gram-positivos (31,2%). Os microrganismos isolados com maior freqüência foram: E. coli (14,6%), S. aureus (13,8%), K. pneumoniae (12,2%), Streptococcus sp. (8,5%), Pseudomonas sp. (7,9%), Staphylococcus coagulase-negativo (7,3%). A sensibilidade dos Bacilos Gram-negativos aos diferentes antimicrobianos foi: Cefepime (63%), Amicacina (65%), Ciprofloxacin (63%), Piperacilina/Tazobactam (71%), Ceftazidima (63%),Meropenem (97%). A sensibilidade dos Cocos Gram-positivos foi: Oxacilina (30%), Levofloxacin (38%), Vancomicina (100%). Comparativamente ao perfil de sensibilidade das unidades de internação clínica adulta não-hematológicas constatou-se diferença estatisticamente significante (p<0,05) entre a sensibilidade dos Bacilos Gram-negativos ao Cefepime (63% x 82%) e a Ceftazidima (63% x 82%) e entre os Cocos Gram-positivos à Oxacilina (30% x 50%). Conclusões: A coleta constante de dados sobre a prevalência dos germes e sua sensibilidade aos antimicrobianos é indispensável para o estabelecimento de tratamentos empíricos para a NF. O perfil de sensibilidade diferenciado em relação às demais unidades de internação faz necessária a criação de protocolos específicos de tratamento da NF. Unitermos: Neutropenia febril; hemoculturas; epidemiologia; perfil de sensibilidadehematologia

Effect of the mother tree age and acorn weight in the regenerative characteristics of Quercus faginea

[EN] The establishment of oak trees is often a slow and difficult process. Hence, it is necessary to determine the characteristics that can lead to improving their regeneration. In this genus, seed size is highly variable both at the interspecific and intraspecific levels, and the effects of intrapopulation variability are not well understood, being even less so for Quercus faginea. In this study, the effects of the age of the mother tree, seed weight and the interaction between these two factors on seed germination, emergence and growth (biomass) were analysed. For this purpose, 16 trees—8 young and 8 old—were selected with the intent to cover the entire range of acorn weights produced in this population. Among the main results, it should be noted that: (1) in older trees, it is easier to find larger acorns; (2) the percentage and the speed of germination of the acorns of young trees is greater than that of old trees; (3) the percentage and the speed of seedling emergence of young trees is greater than that of old trees; and (4) cotyledon weight is the variable that most influences biomass, quite often in a positive way. Therefore, maintaining intrapopulation variability seems to be an approach that most favours the persistence of these populations

A methodology for procedural piano music composition with mood templates using genetic algorithms

Creating music in an automatic way has been studied since the beginning of artificial intelligence. One of the biggest obstacles of music generation is the vagueness and subjectivity of the mood or emotion transmitted by a music piece. In this work, we experiment with the generation of piano music using template pieces, represented in MIDI format, as a mood directive. We generated a population of random pieces for templates of two opposing moods - happy and sad - and evolved them with a genetic algorithm until their intended mood was close enough to their respective templates. The fitness function that we implemented uses MIDI statistical features to calculate the distance between the given piece and the template. The generated music pieces were evaluated by human listeners thorough a questionnaire. This evaluation has shown that the generated music pieces were able to express the same mood as the template. However, they still sounded computer-generated, probably due to the lack of rhythm regularity and synchronicity

Regeneration dynamics in fragmented landscapes at the leading edge of distribution: Quercus suber woodlands as a study case

[EN] Aims We studied the regeneration dynamics of woodlands and abandoned old fields in a landscape dominated by Quercus suber in its lower limits of rainfall and temperature. Two hypotheses were established: (1) regeneration of Quercus species is strongly favored by the presence of tree cover; and (2) growth of Q. suber is driven by the climatic variables that represent the lower ecological limit of its leading distribution edge. Methods We selected woodlands and old fields with and without tree remnants (n = 3 per type), and analyzed stand structure, soil parameters and tree growth. Results Succession was arrested in old fields without tree remnants. By contrast, remnant trees were accelerators of forest recovery in old fields. Tree cover played a fundamental role in Quercus recruitment throughout seed dispersal and facilitation that mitigate the effects of summer drought on seedlings. Also, tree cover improved soil parameters (e.g., organic matter) that are important factors for understanding differences in regeneration. Winter/spring precipitation exerted a positive effect on tree growth, as well as temperatures during winter/spring and September. Conclusions Regeneration dynamics are modeled by the density of tree cover in the cold and dry edge of the distribution area of Q. suber where Q. ilex is increasing in abundance. Although temperature has a positive effect on the tree growth of Q. suber, when demographic processes are considered, decreases in water availability likely play a critical role in Q. ilex recruitment. This in turn changes dominance hierarchies, especially in abandoned areas with little or no tree cover.This study was funded by project SA013G19 from “Junta de Castilla y León” and by research grants awarded for final projects directed in the Master’s degree in Biology and Conservation of Biodiversity at the University of Salamanca, Spain.Publicación en abierto financiada por el Consorcio de Bibliotecas Universitarias de Castilla y León (BUCLE), con cargo al Programa Operativo 2014ES16RFOP009 FEDER 2014-2020 DE CASTILLA Y LEÓN, Actuación:20007-CL - Apoyo Consorcio BUCL