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O presente trabalho apresenta o ensaio fotográfico 'Pessoas com Relações com Pessoa', através de 12 dos 42 retratos de recitadores de sonetos pessoanos que constituem o corpo de uma futura exposição. As fotos são organizadas em quatro trípticos fotográficos, cada um deles sendo precedido do soneto respectivo em edição crítica. A apresentação do ensaio fotográfico inclui uma nota artística introdutória, o aparato crítico-genético dos sonetos retratados e referências bibliográficas.

Although chickens can improve the chemical properties of soil through the deposition of excreta, their effects on soil macrofauna are poorly known. This work assessed the effects of grazing indigenous laying hens on soil macrofauna of two agroecosystems in Portugal: an organic horticultural field and a conventional orchard. At the horticultural field, laying hens were used to control weeds and the results were compared with those of two other weed control treatments: mechanical (rototiller) and thermal (flame weeding). At the orchard, the effects of hens were compared to that of the orchard understory vegetation, as a control. Soil epigeic macrofauna was collected in both locations, and earthworms were only collected in the horticultural field. Relative to the other treatments, grazing in the horticultural field increased the density of earthworms in the medium term (ranging from 150 to 625 earthworms/m2), without harming the density and diversity of epigeic macrofauna. However, at the orchard, the grazed soils presented lower soil epigeic macrofauna diversity, as well as significantly lower density of spiders than the control (4.67 vs 8.67 individuals/sample, respectively). These results suggest that the grazing effects can be affected by several factors, including the type of agroecosystem and farm management. Further research is required to optimize grazing management in different farming systems, considering animal density and grazing duration, thus ensuring the best contributions of chickens to soil fertility.

In this work, the effect of the addition of reduced graphene oxide (rGO) nanoflllers to UHMWPE was investigated. The UHMWPE/rGO nanocomposites were prepared at rGO contents of 0.010, 0.10, 0.25, and 0.50 wt%. The morphological, mechanical, and surface properties of the nanocomposites and the neat UHMWPE were evaluated and related with their tribological behavior. For that, DSC, SEM, contact angle, MO, and profilometry techniques, besides shore D hardness tests, instrumented indentation tests and pin-on-disc sliding wear tests were performed. The results showed that nanocomposites with rGO contents of 0.10 and 0.25 wt% exhibited higher crystallinity degree than the neat UHMWPE, which improved significantly their mechanical and tribological behavior through increases of around 40% in the instrumented hardness and the elastic modulus, and a significant reduction of up to 48% in the coefficient of friction when compared to the neat UHMWPE. Additionally, the presence of rGO decreased the work of adhesion of the nanocomposites/ counterface pairs, resulting in friction and wear mechanisms changes in comparison with the neat polymer. KEYWORDS friction, nanocomposites, reduced graphene oxide, sliding wear, UHMWPE, work of adhesion, 1 | INTRODUCTION Ultra-high molecular weight polyethylene (UHMWPE) has been extensively used in engineering applications that involve wear and friction due to their self-lubricity, lightweight, corrosion resistance, and low coefficient [...]

The 2022 Economic Report of the President devotes a whole chapter to the role of monopsony, monopoly, and discrimination as barriers to economic equality. That monopsony power --market power held [...]

Hypoxia increases inspiratory muscle work and consequently contributes to a reduction in exercise performance. We evaluate the effects of inspiratory muscle warm-up (IMW) on a 10 km cycling time trial in normoxia (NOR) and hypoxia (HYP). Eight cyclists performed four time trial sessions, two in HYP (FiO2: 0.145) and two in NOR (FiO2: 0.209), of which one was with IMW (set at 40% of maximal inspiratory pressure—MIP) and the other was with the placebo effect (PLA: set at 15% MIP). Time trials were unchanged by IMW (NORIMW: 893.8 ± 31.5 vs. NORPLA: 925.5 ± 51.0 s; HYPIMW: 976.8 ± 34.2 vs. HYPPLA: 1008.3 ± 56.0 s; p > 0.05), while ventilation was higher in HYPIMW (107.7 ± 18.3) than HYPPLA (100.1 ± 18.9 L.min−1; p ≤ 0.05), and SpO2 was lower (HYPIMW: 73 ± 6 vs. HYPPLA: 76 ± 6%; p ≤ 0.05). A post-exercise-induced reduction in inspiratory strength was correlated with exercise elapsed time during IMW sessions (HYPIMW: r = −0.79; p ≤ 0.05; NORIMW: r = −0.70; p ≤ 0.05). IMW did not improve the 10 km time trial performance under normoxia and hypoxia. [ABSTRACT FROM AUTHOR]

Taking advantage of a large ensemble of Convection Permitting‐Regional Climate Models on a pan‐Alpine domain and of an object‐oriented dedicated analysis, this study aims to investigate future changes in high‐impact fall Mediterranean Heavy Precipitation Events at high warming levels. We identify a robust multi‐model agreement for an increased frequency from central Italy to the northern Balkans combined with a substantial extension of the affected areas, for a dominant influence of the driving Global Climate Models for projecting changes in the frequency, and for an increase in intensity, area, volume and severity over the French Mediterranean. However, large quantitative uncertainties persist despite the use of convection‐permitting models, with no clear agreement in frequency changes over southeastern France and a large range of plausible changes in events' properties, including for the most intense events. Model diversity and international coordination are still needed to provide policy‐relevant climate information regarding precipitation extremes. Plain Language Summary: Despite growing computational resources and multiple model developments, projecting future changes in the high‐impact Mediterranean Heavy Precipitation Events remains both a numerical and scientific challenge. The present study takes advantage of the recent availability of a relatively large ensemble of high resolution Regional Climate Models (2–3 km), which represent a step change in the simulation of precipitation extremes, and of an object‐oriented approach, allowing us to track the convective precipitating systems on an hourly basis. Looking at future changes in fall Mediterranean Heavy Precipitation Events at high warming levels, we identify a robust multi‐model agreement for an increased frequency from central Italy to the northern Balkans combined with a substantial expansion of the affected areas, and an increase in intensity, area, volume and severity over the French Mediterranean. However, considerable uncertainties remain in terms of frequency over parts of the domain arising from uncertainty in changes in large scale weather patterns, and in terms of degree of intensification for the most intense events. It suggests the need for model diversity and for more coordinated high resolution climate projections with careful selection of different driving global models in order to provide policy‐relevant climate information regarding precipitation extremes. Key Points: High‐resolution ensemble and object‐oriented approach offer a unique opportunity to study changes in Mediterranean extreme precipitationRobust agreement is found for an increase in intensity, volume and severity for future French Mediterranean Heavy Precipitation EventsEven at convection‐permitting scale, considerable uncertainty remains regarding the degree of intensification of the most extreme events [ABSTRACT FROM AUTHOR]

Drought is a complex climatic phenomenon characterized by water scarcity recognized as the most widespread and insidious natural hazard, posing significant challenges to ecosystems and human society. In this study, we propose a new daily based index for characterizing droughts, which involves standardizing precipitation and/or precipitation minus potential evapotranspiration data. The performance of this new index is assessed with data from the evaluation runs of the Coordinated Regional Climate Downscaling Experiment for the European domain and the observational data from the Iberian Gridded Dataset, covering the period from 1989 to 2009. Comparative assessments are conducted against the daily Standardized Precipitation Index (SPI), the Standardized Precipitation Evapotranspiration Index (SPEI), and a simple Z-Score standardization of climatic variables. Seven different accumulation periods are considered (7, 15, 30, 90, 180, 360, and 720 days) with three drought levels: moderate, severe, and extreme. The evaluation focuses mainly on the direct comparison amongst indices, added value assessment using the Distribution Added Value and a simple bias difference for drought characteristics. Results reveal that not only does the new index allow the characterization of flash droughts, but also demonstrates added value when compared to SPI and SPEI, especially for longer accumulation periods. In comparison to the Z-Score, the new index shows slightly greater gains, particularly for extreme drought events at lower accumulation periods. Furthermore, an assessment of the spatial extent of drought for the 2004–2005 event is performed using the observational dataset. All three indices generally provide similar representations, except for the Z-Score, which exhibits limitations in capturing extreme drought events at lower accumulation periods. Overall, the findings suggest that the new index offers improved performance and adds value comparatively to similar indices with a daily time step. [ABSTRACT FROM AUTHOR]

Deep learning (DL) methods have recently garnered attention from the climate change community for being an innovative approach to downscaling climate variables from Earth system and global climate models (ESGCMs) with horizontal resolutions still too coarse to represent regional- to local-scale phenomena. In the context of the Coupled Model Intercomparison Project phase 6 (CMIP6), ESGCM simulations were conducted for the Sixth Assessment Report (AR6) of the Intergovernmental Panel on Climate Change (IPCC) at resolutions ranging from 0.70 to 3.75 ∘. Here, four convolutional neural network (CNN) architectures were evaluated for their ability to downscale, to a resolution of 0.1 ∘ , seven CMIP6 ESGCMs over the Iberian Peninsula – a known climate change hotspot, due to its increased vulnerability to projected future warming and drying conditions. The study is divided into three stages: (1) evaluating the performance of the four CNN architectures in predicting mean, minimum, and maximum temperatures, as well as daily precipitation, trained using ERA5 data and compared with the Iberia01 observational dataset; (2) downscaling the CMIP6 ESGCMs using the trained CNN architectures and further evaluating the ensemble against Iberia01; and (3) constructing a multi-model ensemble of CNN-based downscaled projections for temperature and precipitation over the Iberian Peninsula at 0.1 ∘ resolution throughout the 21st century under four Shared Socioeconomic Pathway (SSP) scenarios. Upon validation and satisfactory performance evaluation, the DL downscaled projections demonstrate overall agreement with the CMIP6 ESGCM ensemble in magnitude for temperature projections and sign for the projected temperature and precipitation changes. Moreover, the advantages of using a high-resolution DL downscaled ensemble of ESGCM climate projections are evident, offering substantial added value in representing regional climate change over Iberia. Notably, a clear warming trend is observed in Iberia, consistent with previous studies in this area, with projected temperature increases ranging from 2 to 6 ∘ C, depending on the climate scenario. Regarding precipitation, robust projected decreases are observed in western and southwestern Iberia, particularly after 2040. These results may offer a new tool for providing regional climate change information for adaptation strategies based on CMIP6 ESGCMs prior to the next phase of the European branch of the Coordinated Regional Climate Downscaling Experiment (EURO-CORDEX) experiments. [ABSTRACT FROM AUTHOR]

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