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Povzetek: The targeted therapy with tyrosine kinase inhibitors (TKIs) against the epidermal growth factor receptor mutation (EGFRm) in advanced non-small cell lung cancer (NSCLC) changed the treatment paradigm. REFLECT study (NCT04031898) explored EGFR/T790M testing and treatment patterns in EGFRm NSCLC patients receiving first- or second-generation (1G/2G) EGFR TKIs as front-line (1L) in eight countries. Pooled data from Central Eastern Europe (CEE) countries from this study (Bulgaria, Poland, Romania, Slovenia) are presented here. This physician-led chart review study was conducted in patients with confirmed-EGFRm NSCLC initiating 1L 1G/2G EGFR TKIs between 2015–2018. The CEE cohort included 389 patients receiving 1L erlotinib (37%), afatinib (34%), and gefitinib (29%). Overall, 320 (82%) patients discontinued 1L, and 298 (77%) progression events were registered. Median progression free survival on 1L TKIs was 14.0 (95% CI: 12.6–15.6) months. Median overall survival from 1L start was 26.6 (95% CI: 24.1–29.0) months. Attrition rate between 1L and next line was 30%. Among patients with 1L progression, 200 (67%) were tested for T790M and 58% were positive. This first CEE analysis of treatments and outcomes in EGFRm NSCLC patients highlights the importance of using the most efficacious therapies currently available in 1L to reduce attrition and improve patient outcomes.
Ključne besede: lung neoplasms, non-small cell lung carcinoma, Eastern Europe, real-world study, REFLECT study, epidermal growth factor receptor, lung cancer
Objavljeno v DiRROS: 09.09.2022; Ogledov: 162; Prenosov: 55
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Povzetek: Tree mortality is a key driver of forest dynamics and its occurrence is projected to increase in the future due to climate change. Despite recent advances in our understanding of the physiological mechanisms leading to death, we still lack robust indicators of mortality risk that could be applied at the individual tree scale. Here, we build on a previous contribution exploring the differences in growth level between trees that died and survived a given mortality event to assess whether changes in temporal autocorrelation, variance, and synchrony in time-series of annual radial growth data can be used as early warning signals of mortality risk. Taking advantage of a unique global ring-width database of 3065 dead trees and 4389 living trees growing together at 198 sites (belonging to 36 gymnosperm and angiosperm species), we analyzed temporal changes in autocorrelation, variance, and synchrony before tree death (diachronic analysis), and also compared these metrics between trees that died and trees that survived a given mortality event (synchronic analysis). Changes in autocorrelation were a poor indicator of mortality risk. However, we found a gradual increase in interannual growth variability and a decrease in growth synchrony in the last %20 years before mortality of gymnosperms, irrespective of the cause of mortality. These changes could be associated with drought-induced alterations in carbon economy and allocation patterns. In angiosperms, we did not find any consistent changes in any metric. Such lack of any signal might be explained by the relatively high capacity of angiosperms to recover after a stress-induced growth decline. Our analysis provides a robust method for estimating early-warning signals of tree mortality based on annual growth data. In addition to the frequently reported decrease in growth rates, an increase in inter-annual growth variability and a decrease in growth synchrony may be powerful predictors of gymnosperm mortality risk, but not necessarily so for angiosperms.
Ključne besede: tree mortality, ring-width, forest, growth, resilience indicators, drought, biotic agents, variance
Objavljeno v DiRROS: 20.07.2022; Ogledov: 230; Prenosov: 158
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Ključne besede: aluminum alloy, metallic whiskers, residual stress, crystal growth, oxidation
Objavljeno v DiRROS: 06.05.2022; Ogledov: 272; Prenosov: 81
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Povzetek: Increased frequency and severity of stressful events affects the growth patterns and functioning of trees which adjust their phenology to given conditions. Here, we analysed environmental effects (temperature, precipitation, VPD and SWC) on the timing of leaf phenology, seasonal stem radial growth patterns, and xylem and phloem anatomy of Quercus pubescens in the sub-Mediterranean in the period 2014%2019, when various adverse weather events occurred, i.e. spring drought in 2015, summer fire in 2016 and summer drought in 2017. Results showed that the timings of leaf and cambium phenology do not occur simultaneously in Q. pubescens, reflecting different environmental and internal constraints. Although year-to-year variability in the timings of leaf and cambial phenology exists, their chronological sequence is fairly fixed. Different effects of weather conditions on different stages of leaf development in spring were observed. Common climatic drivers (i.e., negative effect of hot and dry summers and a positive effect of increasing moisture availability in winter and summer) were found to affect the widths of xylem and phloem increments with more pronounced effect on late formed parts. A legacy effect of the timing of leaf and cambial phenology of the previous growing season on the timing of phenology of the following spring was confirmed. Rarely available phloem data permitted a comprehensive insight into the interlinkage of the timing of cambium and leaf phenology and adjustment strategies of vascular tissues in Mediterranean pubescent oak to various environmental constraints, including frequent extreme events (drought, fire). Our results suggest that predicted changes in autumn/winter and spring climatic conditions for this area could affect the timings of leaf and stem cambial phenology of Q. pubescens in the coming years, which would affect stem xylem and phloem structure and hydraulic properties, and ultimately its performance.
Ključne besede: pubescent oak, leaf development, radial growth, initial earlywood vessel, sieve tube, anatomy, cambial cell production, extreme weather events
Objavljeno v DiRROS: 06.09.2021; Ogledov: 613; Prenosov: 105
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Povzetek: This paper investigates how variation in forest structural characteristics affects the water retention capacity of gaps and forests in fir-beech forests in the Dinaric Karst. Forests are identified as a key element of the landscape for provision of pristine water resources, particularly in highly vulnerable karst aquifers characterized by rapid infiltration of recharge water, high subsurface permeability, and heterogeneous underground flow. Indicators of hydrologic fluxes (drainage flux, canopy interception, transpiration, and soil evaporation) in a large experimental gap (approximately 0.2 ha in size) and those in a nearby old-growth gap were compared over a 13-year period using the Brook90 hydrological model and their structural characteristics were analyzed. In addition, the hydrologic fluxes were also simulated for a managed forest and an old-growth forest for reference. Water regulation capacity was lowest in the experimental gap, where drainage flux accounted for 81% of precipitation and the sum of canopy interception, transpiration, and soil evaporation (evapotranspiration) accounted for 18%. This was followed by the old-growth gap, where drainage flux accounted for 78% of precipitation and evapotranspiration for 23%. Water retention capacity was highest and generally similar for both forests, where 71%72% of annual precipitation drained to the subsurface. The results of this study suggest that the creation of large canopy gaps in fir-beech forests in the Dinaric Karst results in significant and long-lasting reduction in soil and vegetation water retention capacity due to unfavorable conditions for successful natural tree regeneration. For optimal provision of water regulation ecosystem services of forests in the Dinaric Karst, small, irregularly shaped canopy gaps no larger than tree height should be created, mimicking the structural characteristics of naturally occurring gaps in old-growth forests.
Ključne besede: water retention capacity, drainage flux, evapotranspiration, Brook90 hydrological model, experimental canopy gap, old-growth forest
Objavljeno v DiRROS: 05.03.2021; Ogledov: 710; Prenosov: 641
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