Recovery Assessment of Open-heart Cardiac Surgery Patients Using Heart Rate Variability Parameters

Surgical operation causes short-term stress changing the balance of the autonomic nervous system (ANS). The ANS activity can be assessed through heart rate variability (HRV). This work aims to evaluate the recovery process of open-heart cardiac surgery patients under two post-surgery physiotherapy interventions using HRV parameters. Ten-minute ECG recordings were performed on 17 open-heart cardiac surgery patients pre-operatively (PREOP) and during three consecutive post-operative days (POD1, POD2 and POD3). The recovery process was promoted using two different physiotherapy techniques: positive expiratory pressure (PEP, N = 9) and inspiratory training (IMT, N = 8). Common HRV parameters (SDNN, LF power and SD1) were calculated for each patient and statistical analyses were performed. The results show significant differences between HRV parameters pre- and post-operatively, and there was a reduction of all three investigated HRV parameters in the POD1 for both groups. HRV parameters average values increased between POD1 to POD3 for both intervention groups indicating that patients were eventually starting to recover from the surgery. Statistically significant difference between PEP and IMT interventions was not discovered (e.g., p = 0.54 for SDNN, PREOP vs. POD3). Based on the results, all studied HRV parameters are potential indicators of the short-term recovery after cardiac surgery.Peer reviewe

Similar understorey structure in spite of edaphic and floristic dissimilarity in Amazonian forests

Forest structure determines light availability for understorey plants. The structure of lowland Amazonian forests is known to vary over long edaphic gradients, but whether more subtle edaphic variation also affects forest structure has not beenresolved. In western Amazonia, the majority of non-flooded forests grow on soils derived either from relatively fertile sediments of the Pebas Formation or from poorer sediments of the Nauta Formation. The objective of this study was to compare structure and light availability in the understorey of forests growing on these two geological formations. We measured canopy openness and tree stem densities in three size classes in northeastern Peru in a total of 275 study points in old-growth terra firme forests representing the two geological formations. We also documented variation in floristic composition (ferns, lycophytes and the palm Iriartea deltoidea) and used Landsat TM satellite image information to model the forest structural and floristic features over a larger area. The floristic compositions of forests on the two formations were clearly different, and this could also be modelled with the satellite imagery. In contrast, the field observations of forest structure gave only a weak indication that forests on the Nauta Formation might be denser than those on the Pebas Formation. The modelling of forest structural features with satellite imagery did not support this result. Our results indicate that the structure of forest understorey varies much less than floristic composition does over the studied edaphic difference

The utilization of industrial by-products as soil conditioners and fertilizers in non-food potato production

Abstract Peatlands require soil improvement to be suitable for cultivation. Creating eco-friendly and cost-effective carbon sinks in peatlands originated from peat production has several benefits. For this purpose various valuable biomass can be used by utilizing industrial by-products also as soil conditioners and fertilizers. For example, the addition of such materials has potential to transform peat bogs, which otherwise would slowly release methane, into productive cultivated areas. The rehabilitation of peat bogs from unused land into various agricultural and forestry areas is also a viable business activity. The examined industrial by-products could have many agricultural applications in non-food potato production, wherein monoculture causes problems such as condensed soil, lost humus or soil organic matter, and reduced nutrient retention capacity, leading to increased leaching of nutrients and negative impacts on the environment. Five industrial by-products were examined in this study as soil conditioners and fertilizers: fiber sludge, biocarbon, hygienic biodige state, paper mill sludge, and gypsum waste. Based on the results of a nutrient content analysis, hygienic biodigestate and fiber sludge were the most effective fertilizers