Plant Regeneration Above the Species Elevational Leading Edge: Trade-Off Between Seedling Recruitment and Plant Production

Mountains and their biota are highly threatened by climate change. An important strategy that alpine plants use to escape this change consists in seed dispersal and the ability of seeds to germinate and establish in new sites at higher elevation. Little is known about the environmental factors that can affect the regeneration of plants above the elevational limit of growth. We present the first field evidence of recruitment success and plant performance in consequence of upward shift from the alpine to the nival life zone. Seeds of four alpine grassland species were sown at the current elevational limit of growth (site A) and 200 m upward, in a nival environment (site N) located in the Italian Alps. At site N part of the seeds were subjected to experimental manipulation of temperature (using an Open Top Chamber, OTC) or soil (using soil from site A). Recruitment success, soil surface temperature and water potential were monitored for five consecutive years. At the end of the experiment, vegetative growth and foliar traits were measured on individuals from all treatments. Mean annual soil surface temperature and length of the growing season at site A were ca. 2°C higher and ca. 44 days longer than at site N. Seedling emergence and seedling establishment generally were higher at N (with or without OTC) on local soil than at site A or at site N with soil originating from site A. Conversely, production was higher at site A and at site N with soil originating from site A. Recruitment success above the elevational leading edge was enhanced by coarser and nutrient-poor soil, which promoted seedling emergence and establishment but constrained plant growth. This trade-off between seedling recruitment and plant production underlines adaptive consequence and environmental filtering, both critical to forecast community assembly and responses of alpine species to climate warming

A New Generation of Hydrogen-Fueled Hybrid Propulsion Systems for the Urban Mobility of the Future

The H2-ICE project aims at developing, through numerical simulation, a new generation of hybrid powertrains featuring a hydrogen-fueled Internal Combustion Engine (ICE) suitable for 12 m urban buses in order to provide a reliable and cost-effective solution for the abatement of both CO2 and criteria pollutant emissions. The full exploitation of the potential of such a traction system requires a substantial enhancement of the state of the art since several issues have to be addressed. In particular, the choice of a more suitable fuel injection system and the control of the combustion process are extremely challenging. Firstly, a high-fidelity 3D-CFD model will be exploited to analyze the in-cylinder H2 fuel injection through supersonic flows. Then, after the optimization of the injection and combustion process, a 1D model of the whole engine system will be built and calibrated, allowing the identification of a “sweet spot” in the ultra-lean combustion region, characterized by extremely low NOx emissions and, at the same time, high combustion efficiencies. Moreover, to further enhance the engine efficiency well above 40%, different Waste Heat Recovery (WHR) systems will be carefully scrutinized, including both Organic Rankine Cycle (ORC)-based recovery units as well as electric turbo-compounding. A Selective Catalytic Reduction (SCR) aftertreatment system will be developed to further reduce NOx emissions to near-zero levels. Finally, a dedicated torque-based control strategy for the ICE coupled with the Energy Management Systems (EMSs) of the hybrid powertrain, both optimized by exploiting Vehicle-To-Everything (V2X) connection, allows targeting H2 consumption of 0.1 kg/km. Technologies developed in the H2-ICE project will enhance the know-how necessary to design and build engines and aftertreatment systems for the efficient exploitation of H2 as a fuel, as well as for their integration into hybrid powertrains

Dementia-related genetic variants in an Italian population of early-onset Alzheimer’s disease

Early-onset Alzheimer’s disease (EOAD) is the most common form of early-onset dementia. Although three major genes have been identified as causative, the genetic contribution to the disease remains unsolved in many patients. Recent studies have identified pathogenic variants in genes representing a risk factor for developing Alzheimer’s disease (AD) and in causative genes for other degenerative dementias as responsible for EOAD. To study them further, we investigated a panel of candidate genes in 102 Italian EOAD patients, 45.10% of whom had a positive family history and 21.74% with a strong family history of dementia. We found that 10.78% of patients carried pathogenic or likely pathogenic variants, including a novel variant, in PSEN1, PSEN2, or APP, and 7.84% showed homozygosity for the ε4 APOE allele. Additionally, 7.84% of patients had a moderate risk allele in PSEN1, PSEN2, or TREM2 genes. Besides, we observed that 12.75% of our patients carried only a variant in genes associated with other neurodegenerative diseases. The combination of these variants contributes to explain 46% of cases with a definite familiarity and 32% of sporadic forms. Our results confirm the importance of extensive genetic screening in EOAD for clinical purposes, to select patients for future treatments and to contribute to the definition of overlapping pathogenic mechanisms between AD and other forms of dementia

Isoprene and monoterpene fluxes from central amazonian rainforest inferred from tower-based and airborne measurements, and implications on the atmospheric chemistry and the local carbon budget

We estimated the isoprene and monoterpene source strengths of a pristine tropical forest north of Manaus in the central Amazon Basin using three different micrometeorological flux measurement approaches. During the early dry season campaign of the Cooperative LBA Airborne Regional Experiment (LBA-CLAIRE-2001), a tower-based surface layer gradient (SLG) technique was applied simultaneously with a relaxed eddy accumulation (REA) system. Airborne measurements of vertical profiles within and above the convective boundary layer (CBL) were used to estimate fluxes on a landscape scale by application of the mixed layer gradient (MLG) technique. The mean daytime fluxes of organic carbon measured by REA were 2.1 mg C m^−2 h^−1 for isoprene, 0.20 mg C m^−2 h^−1 for α-pinene, and 0.39 mg C m^−2 h^−1 for the sum of monoterpenes. These values are in reasonable agreement with fluxes determined with the SLG approach, which exhibited a higher scatter, as expected for the complex terrain investigated. The observed VOC fluxes are in good agreement with simulations using a single-column chemistry and climate model (SCM).\ud \ud In contrast, the model-derived mixing ratios of VOCs were by far higher than observed, indicating that chemical processes may not be adequately represented in the model. The observed vertical gradients of isoprene and its primary degradation products methyl vinyl ketone (MVK) and methacrolein (MACR) suggest that the oxidation capacity in the tropical CBL is much higher than previously assumed. A simple chemical kinetics model was used to infer OH radical concentrations from the vertical gradients of (MVK+MACR)/isoprene. The estimated range of OH concentrations during the daytime was 3–8×10^6 molecules cm^−3, i.e., an order of magnitude higher than is estimated for the tropical CBL by current state-of-the-art atmospheric chemistry and transport models. The remarkably high OH concentrations were also supported by results of a simple budget analysis, based on the flux-to-lifetime relationship of isoprene within the CBL. Furthermore, VOC fluxes determined with the airborne MLG approach were only in reasonable agreement with those of the tower-based REA and SLG approaches after correction for chemical decay by OH radicals, applying a best estimate OH concentration of 5.5×10^6 molecules cm^−3. The SCM model calculations support relatively high OH concentration estimates after specifically being constrained by the mixing ratios of chemical constituents observed during the campaign.\ud \ud The relevance of the VOC fluxes for the local carbon budget of the tropical rainforest site during the measurements campaign was assessed by comparison with the concurrent CO2 fluxes, estimated by three different methods (eddy correlation, Lagrangian dispersion, and mass budget approach). Depending on the CO2 flux estimate, 1–6% or more of the carbon gained by net ecosystem productivity appeared to be re-emitted through VOC emissions

Maturidade emocional, locus de controle e ansiedade em pré- adolescentes obesos

Investigou-se aspectos do funcionamento psicológico como a maturidade emocional, locus de controle e ansiedade em pré-adolescentes obesos, através dos instrumentos: Teste do Desenho da Figura Humana (DFH), Escala de Locus de Controle para crianças e Escala de Ansiedade "RCMS". Os resultados não apontaram uma tendência específica quanto ao locus de controle ser mais interno ou externo. Em relação à ansiedade, enquanto traço de personalidade, a maioria dos sujeitos situou-se dentro do esperado para seu grupo etário. No DFH os índices relativos à Escala Evolutiva e à Escala Emocional encontraram-se também dentro do esperado, em sua maior parte. Tais resultados sugerem que não existe diferença entre pré-adolescentes obesos e pré-adolescentes em geral, quanto às variáveis estudadas. Entretanto, ser obeso pode estar associado a dificuldades de elaboração de aspectos evolutivos e emocionais para alguns indivíduos.Aspects of psychological functioning such as emotional maturity, locus of control and anxiety had been evaluated in obese preadolescents. The following instruments were used: Draw a Person Test - DAT; Locus of Control Scale for Children and the Revised Children Manifest Anxiety Scale (Portuguese versions). Results show no tendency for the locus of control to be more external or internal, when compared to normative data. The scores of anxiety, as personality trait, are compatible to the normative data. The DAT analysis showed that most of the results related to Developmental and Emotional Scales are within the norm values. These results suggest no differences between obese preadolescents and preadolescents in general, related to the aspects approached in this study. They also suggest that, for some individuals, being obese may be associated to some emotional suffering and difficulties in dealing with developmental aspects

Emotional maturity, locus of control and anxiety in obese preadolescents

Investigou-se aspectos do funcionamento psicológico como a maturidade emocional, locus de controle e ansiedade em pré-adolescentes obesos, através dos instrumentos: Teste do Desenho da Figura Humana (DFH), Escala de Locus de Controle para crianças e Escala de Ansiedade "RCMS". Os resultados não apontaram uma tendência específica quanto ao locus de controle ser mais interno ou externo. Em relação à ansiedade, enquanto traço de personalidade, a maioria dos sujeitos situou-se dentro do esperado para seu grupo etário. No DFH os índices relativos à Escala Evolutiva e à Escala Emocional encontraram-se também dentro do esperado, em sua maior parte. Tais resultados sugerem que não existe diferença entre pré-adolescentes obesos e pré-adolescentes em geral, quanto às variáveis estudadas. Entretanto, ser obeso pode estar associado a dificuldades de elaboração de aspectos evolutivos e emocionais para alguns indivíduos.Aspects of psychological functioning such as emotional maturity, locus of control and anxiety had been evaluated in obese preadolescents. The following instruments were used: Draw a Person Test - DAT; Locus of Control Scale for Children and the Revised Children Manifest Anxiety Scale (Portuguese versions). Results show no tendency for the locus of control to be more external or internal, when compared to normative data. The scores of anxiety, as personality trait, are compatible to the normative data. The DAT analysis showed that most of the results related to Developmental and Emotional Scales are within the norm values. These results suggest no differences between obese preadolescents and preadolescents in general, related to the aspects approached in this study. They also suggest that, for some individuals, being obese may be associated to some emotional suffering and difficulties in dealing with developmental aspects

Kosteletzkya pentacarpos (L.) Ledeb.

Viene definita la distribuzione in Italia di Kosteletzkya pentacarpos e discusso il suo stato di conservazione

Reduction in primary production followed by rapid recovery of plant biomass in response to repeated mid-season droughts in a semiarid shrubland

The frequency and severity of extreme weather events, including droughts, are expected to increase due to the climate change. Climate manipulation field experiments are widely used tools to study the response of key parameters like primary production to the treatments. Our study aimed to detect the effect of drought on the aboveground biomass and primary production both during the treatments as well as during the whole growing seasons in semiarid vegetation. We estimated aboveground green biomass of vascular plants in a Pannonian sand forest-steppe ecosystem in Hungary. We applied non-destructive field remote sensing method in control and drought treatments. Drought treatment was carried out by precipitation exclusion in May and June, and was repeated in each year from 2002. We measured NDVI before the drought treatment, right after the treatment, and at the end of the summer in 2011 and 2013. We found that the yearly biomass peaks, measured in control plots after the treatment periods, were decreased or absent in drought treatment plots, and consequently, the aboveground net primary production was smaller than in the control plots. At the same time, we did not find general drought effects on all biomass data. The studied ecosystem proved resilient, as the biomass in the drought-treated plots recovered by the next drought treatment. We conclude that the effect of drought treatment can be overestimated with only one measurement at the time of the peak biomass, while multiple within-year measurements better describe the response of biomass