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Climate extremes and their impacts on agriculture across the Eastern Corn Belt Region of the U.S.

Wilson, Aaron B. | 2022

The Eastern Corn Belt Region (ECBR) is an important agricultural sector for the U.S. This study analyzes the climate extremes over the contemporary (1980–2018) and future (2036–2099) periods over the ECBR. We evaluated the performance of 32 downscaled models from the U.S. Global Change Research Program's Localized Constructed Analogs (LOCA) of the Coupled Model Intercomparison Project (CMIP5) to simulate extreme temperature and precipitation indices. The LOCA downscaled models were evaluated for the recent past against the National Aeronautics and Space Administration (NASA)-supported gridded observational dataset DAYMET. Results reveal key trends throughout the region that are consistent with previous studies, including significant increases in extreme minimum temperatures, reduction of cold nights, increase of warm nights, and decreases in diurnal temperature ranges. Much of the region demonstrates extreme warming trends in the coldest night of the year (more than 5 °C) and an increase in the heaviest precipitation events over 1980–2018. An optimal model ensemble (OME) was constructed using a Kling-Gupta Efficiency and Bhattacharyya coefficient evaluation to construct a comprehensive ranking procedure. Having outperformed a standard multi-model ensemble approach, the OME was used to evaluate the future changes of extreme climate indices under RCP4.5 and RCP8.5 scenarios. Though the OME showed consistently strong warming throughout the ECBR, variability among the optimal models and across watersheds is quite significant, especially for precipitation indices. Thus, constraining the uncertainty in future climate models, specifically as it relates to agriculture decisions that support climate-resilience, remains a challenge.

Acute coronary syndromes following COVID-19 vaccine application: Kounis syndrome or chance?

Rueda Ibarra, Leonardo | 2022

Agroforestry systems recover tree carbon stock faster than natural succession in Eastern Amazon, Brazil

Gómez Cardozo, Ernesto | 2022

The potential of agroforestry systems (AFS) for atmospheric carbon sequestration in degraded tropical lands is of key interest for climate change and rural development policies. This study evaluated aboveground and soil (0–20 cm) carbon stocks of AFS, secondary forests (SF), conserved and logged mature forests, on 88 sites in the eastern Brazilian Amazon. Tree carbon stock was higher in young (< 10 years) and advanced (> 30 years) AFS (10.2 ± 2.0 and 47.2 ± 8.1 Mg ha−1, respectively) when compared to the same age SF (5.8 ± 2.5 and 26.5 ± 19.5 Mg ha−1). However, aboveground and total carbon stocks were statistically similar within the same age categories of AFS and SF, because shrub pool were higher in SF. Conserved mature forests had the highest carbon stocks (190.2 ± 11.0 Mg ha−1), and carbon stocks in logged mature forests (119.4 ± 5.1 Mg ha−1) were similar to the advanced stages of AFS (108.6 ± 7.5 Mg ha−1). Litter and soil organic carbon (SOC) did not differ significantly between land-use systems nor along succession. At 30 years, aboveground carbon recovery was 46% (± 16) in AFS and 35% (± 21) in SF. Vegetation structural diversity (measured by DBH and height variation) was a good predictor of aboveground carbon stocks. Our results show the potential of AFS for carbon recovery, especially in the tree pool at late stages of development. Structurally more complex AFS provide an alternative to recover degraded lands and to develop synergies between climate change mitigation, adaptation, and goods production in Amazon.

La enfermería latinoamericana y su resignificación social y cultural

Velásquez Jiménez, Claudia Marcela | 2022

El artículo aborda una reflexión sobre la importancia del liderazgo y empoderamiento de la enfermería Latinoamericana como cuerpo colectivo, que tiene una responsabilidad en la participación y construcción de la política pública de salud y su talento humano, a partir de la visibilizacion del aporte que, como disciplina fundamentada en investigación y teoría, realiza al conocimiento basado en evidencia del cuidado de los proceso de salud enfermedad de los individuos familias y colectivos. Plantea, además, la problemática de escasez de profesionales de enfermería en la región, la inequidad en el reconocimiento de su valor como profesión del cuidado humano y la necesidad de acción y protagonismo para enfrentar los desafíos de una real re- significación de la profesión.

Bar Load-Velocity Profile of Full Squat and Bench Press Exercises in Young Recreational Athletes

Fernandez, Jairo Alejandro | 2022

The purpose of this study was to determine the mean propulsive velocity (MVP) at various percentages of one repetition maximum (1RM) in the full squat and chest press exercises. A total of 96 young women and 256 young men (recreational athletes) performed an incremental test (50–60–70–80% 1RM) comprising the bench press and full squat exercises in two different sessions. The individual load and velocity ratios were established through the MPV. Data were analyzed using SPSS software version 25.0, with the significance level set at 5%. The following findings were revealed: highly linear load-velocity relationships in the group of women (r = 0.806 in the squat, and r = 0.872 in the bench press) and in the group of men (r = 0.832 and r = 0.880, respectively); significant differences (p < 0.001) in the MPV at 50–70–80% 1RM between the bench press and the full squat in men and at 70–80% 1RM in women; and a high variability in the MPV (11.49% to 22.63) in the bench press and full squat (11.58% to 25.15%) was observed in women and men (11.31% to 21.06%, and 9.26% to 24.2%) at the different percentages of 1RM evaluated. These results suggest that the load-velocity ratio in non-strength-trained subjects should be determined individually to more precisely establish the relative load to be used in a full squat and bench press training program